Welcome to the website where you can pass online the CBT test on the subject «EO4: Operate Auxiliary Machinery and Control Systems». Practice like this will help you as a marine specialist improve your knowledge with the help of online studying and appraisal practice. CBT based on practical information and marine specialists experience.
CBT tests developed for evaluating seaman basic knowledge by Seagull Company (rebranded as «OTG»), is an evaluating online-tool, used for revealing any professional preparation needed in specific fields of knowledge, defined by STCW.
CBT tests have proven themselves as good tools for the selection and recruitment process, as well as advancing the level of knowledge of the current officers and crew. Ocean Technologies Group use various subjects for question creation, which includes:
- Crowd and Crisis Management;
- Integrated Navigation System (INS);
- Ballast water management;
- Handling and Stowage;
- Vessel operation management and safety;
- Marine engineering;
- Maintenance and repair, etc.
Current test contains Seagull CBT questions on the subject «EO4: Operate Auxiliary Machinery and Control Systems». Those questions can be used for competence verification specialist capable of preventing accidental situations related with transporting safety, or also for self-examination.
«EO4: Operate Auxiliary Machinery and Control Systems» subject includes theoretical and practical information about advanced training for work on any type of vessel. This test comprehensively assesses the knowledge required for the operation of auxiliary machinery and control systems. It evaluates a candidate’s understanding of fundamental principles, including thermodynamics, fluid mechanics and electrical systems, as they apply to shipboard equipment. A significant portion of the examination is dedicated to troubleshooting and diagnosing common faults in systems such as pumps, compressors and purifiers. Practical, scenario-based questions test the ability to start up, shut down and manage the operational parameters of auxiliary machinery in accordance with safety procedures. Furthermore, the test measures competence in using automated control systems and interpreting data from alarm and monitoring panels to maintain optimal plant performance. Safety is a cross-cutting theme, with questions designed to verify knowledge of emergency protocols and the potential hazards associated with machinery operation. Successful completion of this assessment demonstrates technical proficiency and readiness to perform the duties of a marine engineer on various vessel types. The final score provides a reliable benchmark of a candidate’s preparedness for the advanced responsibilities of managing a vessel’s auxiliary systems.
On this site Crew Evaluation System Test on the subject «EO4: Operate Auxiliary Machinery and Control Systems» contains 481 questions you need to answer with no possibility to go back to previous question. Therefore, we recommend carefully reading each question and making decision with no hurry. In case you have some difficulty answering, you have also possibility to request a hint.
The test includes two modes. In the Training mode, you go through 481 questions with the option to take a hint, while in the Exam mode, this option is not available. Enjoy!
Choose the regime, in which you want to pass CES test:
Training
Exam
Wild mode
* Some questions may have more than 1 correct answer.
“CBT test” finished! Your result:
Correct answers:
Use the search below to find question.
Amount of questions: 481.
Right answers marked with this sign .
A boiler burner fails each time it is started with failure indicated as “flame failure“. Indicate the most likely reason.
The fan motor is faulty.
The fuel oil temperature is too high.
The flame cell is dirty.
The electrode cables have the wrong output voltage.
The engine room high level bilge alarm keeps sounding every few minutes even though the bilge is empty. What action would you take?
Change the setting on the alarm printed circuit board.
Check the function of the level switch and the printed circuit board for this alarm group.
Disconnect the alarm and see if it helps.
Start the bilge pump.
What is component number 3 called?
A spring adjuster.
A spring tensioning washer.
A valve cover.
A spring plate.
What is “chatter” in a safety valve?
The first leakage before the valve opens.
A failure of a safety valve to re-seat.
A metallic hammering noise.
A hissing sound indicating that a safety valve is leaking.
Which part is the brine cooler?
D.
H.
K.
C.
Should water be circulated through the main engine during a port stay, and if so why?
No, as this would result in extra water consumption from main engine water leaks.
Yes, as this will maintain watertight condition of hoses and connections.
Yes, circulating the auxiliary jacket water will maintain the main engine temperature.
No, as this will prevent the auxiliary engines attaining the correct temperature.
What is part number 1 called?
The drainage tank.
The expansion tank.
The service tank.
The settlement tank.
Which part is the heater?
Number 1.
Number 2.
Number 3.
Number 4.
Which of the two drawings shows two series connected purifiers?
1.
2.
Neither.
Both 1 and 2.
Where is the inlet for the unclean oil?
Area 1.
Area 2.
Area 3.
Area 4.
What is part number 2 called?
The chamber.
The paring disc.
The distributor.
The bowl hood.
Which part is the paring disc?
Part 2.
Part 3.
Part 4.
Part 6.
What is part number 3 called?
The paring disc for processed oil.
The spring support.
Disc stack support bearing.
The water paring disc.
What is part number 5 called?
The disk holder.
The disc stack.
The paring disc.
The distributor vanes.
Where is the separation carried out?
Position number 1.
Position number 2.
Position number 7.
Position number 5.
What kind of temperature control mode is fitted here?
Controlling outlet by regulating the inlet.
Controlling outlet by regulating the outlet.
Controlling inlet by regulating the inlet.
Controlling inlet by regulating the outlet.
Which kind of cooling water system is used with this compressor?
Forced sea water cooling.
Open free flow sea water cooling.
Forced fresh water cooling.
Free flow fresh water cooling.
What is indicated by position “I” at both of the cylinders?
Water inlet of Intercoolers.
Water inlet of cylinders/intercoolers.
Water inlet of cylinders.
Water inlet of aftercoolers.
Suppose the delivery air pressure of this compressor is 30,0 bar. What class of compressor could this be?
A service air compressor.
An instrument air compressor.
A working air compressor.
A starting air compressor.
What are the units marked “C” fitted on both cylinders?
Aftercoolers.
Intercoolers.
Cylinder blocks.
Cooling water vessels.
When is manual by-pass valve of this compressor cooler “CW” operated?
During normal running to keep the temperature constant.
In the case of a cooler tube leaking.
In cold climates to avoid moisture.
When the compressor is new/overhauled with new rings.
This drawing indicates the timing of the unloader and drains of a compressor. After how many seconds will the compressor pump at full capacity?
7 seconds.
12 seconds.
14 seconds.
Between 7 and 12 seconds.
When starting a compressor, why is it necessary for the unloader to be activated before the drain valves are closed?
So the pumping action can blow the drains through.
To avoid the safety valves blowing.
To avoid air blowing in the bilges.
To prevent the compressor from tripping.
Why is it necessary to start a compressor with the drains open?
To hear that it is delivering pressure and the unloader is working.
To get rid of all the dirt inside.
To blow clear any moisture from the compressor discharge.
To avoid overloading the electric motor.
On what part of the compressor does the unloader act and in what way?
It keeps the suction valves open.
It keeps the suctions valves closed.
It keeps the delivery valves open.
It keeps the delivery valves closed.
What would be the pressure in the air bottle which activates the “PC” and “S” connecting the unloader line with c and a?
Between 6,5 and 8,5 bar.
Between 8,5 and 10,0 bar.
Between 0 and 8,5 bar.
Between 8,5 and 9,35 bar.
In which kind of compressor is this type of piston assembly fitted?
Refrigeration compressor.
CO2 compressor.
Service air compressor.
Oil-free instrument air compressor.
What is the purpose of the stuffing box in this combined piston compressor assembly?
To keep the air of the pumping space separated from the guide.
To prevent oil from being pumped up to the pumping piston.
As sealing between pumping cylinder and guide cylinder.
All of these.
In this oil-free compressor, of what material are the piston rings of the pumping piston “P” made?
Chrome plated.
Slotted chromium.
Plain cast iron.
Carbon.
If you increase fuel flow to the purifier using capacity control valve CC, what other action must you take?
Increase the flow from the settling tank to the purifier.
Throttle steam to the HFO service tank.
Adjust back pressure with back pressure valve BPV.
Drain the service tank at shorter intervals.
What type of pump is the HFO purifier feed pump P?
A centrifugal pump.
A gear pump or worm pump.
A piston pump.
A vane pump.
How is pump “P” driven from the purifier?
By V-belt.
By electric motor.
By shaft drive with replaceable sheer pins from the purifier crankcase.
By direct gear drive from the purifier crankcase.
What is item “F“?
A flow meter.
A flow control device.
A normal mesh filter/strainer.
A fuel shut-off solenoid.
When using marine diesel oil with a density of about 0,87, what would be the inlet temperature of the fuel to the purifier?
30 degree C.
40 degree C.
60 degree C.
85 degree C.
What is the ideal temperature to maintain the diesel oil daily tank and how is this achieved?
45 degree C, by circulating the fuel with the purifier tank.
45 degree C, by application of steam heating.
65 degree C, by application of steam heating.
65 degree C, by circulating the fuel with the purifier tank.
When you start a purifier it takes several minutes to accelerate to full speed since the power from the electric motor is transferred by ____ to the purifier.
A plate clutch.
A magnetic coupling.
A centrifugal clutch.
A rotating coupling.
Which of the following alarms may sound after the automatic de-sludging cycle is completed and the purification of the oil restarts?
The overflow alarm.
The water seal alarm.
The oil high temperature alarm.
The oil high pressure alarm.
In what kind of machinery would this type of gland packing never be used?
Steam valve spindles.
Refrigerating installations.
Sea water or freshwater pumping equipment.
Fuel oil or Lubricating oil systems.
What do you call this device?
A safety lifting valve.
An overpressure blow-off valve.
A straight non-return valve.
A scavenge air valve.
What is the required temperature in the ship’s fish room?
From 0 to – 5 degree C.
From -20 to – 25 degree C.
From -15 to – 20 degree C.
From -5 to -10 degree C.
What is the required temperature in the ship’s dairy room?
From 0 to +3 degree C.
From +3 to +5 degree C.
From -2 to +2 degree C.
From +5 to +7 degree C.
What is the required temperature in the ship’s vegetable room?
From +2 to +4 degree C.
From +4 to +6 degree C.
From +5 to +7 degree C.
From +7 to +10 degree C.
What parameter is controlling the capacity control system of this domestic refrigerating compressor?
The temperature in the refrigerated rooms.
The temperature and back-pressure of the condensor.
The suction pressure of the compressor.
The discharge pressure of the compressor.
Freon is being phased out gradually as a refrigerant. Why?
Because it is too expensive.
Because it is being replaced by more efficient refrigerants.
Because it has a damaging effect on the Earth’s ozone layer.
Because under certain conditions it is toxic.
How are the solenoid valves “S” (fitted before the evaporating banks) controlled?
By the pressure of the evaporating liquid.
By the defrost control panel.
By the evaporator gas outlet temperature.
By the temperature inside the refrigerated compartments.
What is the state of the refrigerant which flows from the condenser to the solenoids and the expansion valves?
It is hot and undercooled.
It is under condenser pressure and undercooled.
It is below condenser pressure and condensed.
It rises above the condenser pressure and decreases in temperature.
Why is there an oil separator “OS” fitted as shown here?
Because Freon absorbs oil and it needs to be separated.
To separate the oil dragged with the Freon from the compressor.
To separate oil during compressor start-up.
To collect the oil before stopping the compressor.
What is the function of the low pressure cut-out fitted on the same manometer line as manometer “SM“?
As safety shut-down device. Inspection and reset are required.
Purely as cut-in/cut-out device by low capacity. No reset required.
As safety power tripping device. Solenoids “S” will also close.
As alarm device only without shut-down function.
What is the function of the high pressure cut-out fitted on the same manometer pipe as manometer “DM“?
As safety cut-out with additional alarm function. Manual reset required.
As operational cut-out when condenser pressurised prolonged.
As electrical overload and alarm, auto reset.
As alarm device only.
What is the function of the oil differential pressure cut-out fitted between the manometer pipes of manometers “P” and “SM“?
As temporary cut-out.
As high temperature warning.
As warning/cut out due to oil foaming.
As a low lub oil pressure cut-out.
If during your watch the air-conditioning compressor cuts-out because of high discharge pressure, what are you going to check immediately?
If the accommodation vent fan has tripped.
The level of the receiver, to see if the Freon has escaped.
That there is sufficient cooling water to the condenser.
Ice formation on the evaporating unit.
Why is there a receiver fitted below the condenser of an air-conditioning unit unlike on the condenser of the domestic fridge system?
Because the air-conditioning does not run in winter climates.
To store spare Freon.
Because there is more chance of leakage and Freon escape.
Because the capacity is larger.
You are notified that it is getting hot in the accommodation and the air conditioning is not working. What do you check immediately?
If the aircon compressor is still running.
If suction and discharge pressures on the compressor are normal.
If the accomodation vent fans are running.
If there is sufficient refrigerant in the system.
When should the recirculation of air from the accommodation be set to 100 % and the fresh air intake totally closed?
When outside temperature is more than 30 degree C.
During cargo operations or cargo transfer in port or at sea.
When outside temperature is more than 36 degree C.
When vessel is moored at an oil refinery.
What is the most important item of maintenance required to ensure maximum efficiency of the accomodation air conditioning plant?
Clean the central air conditioning fan unit intake suction filters.
Ensure always that there is sufficient Freon in the receiver.
Ensure the evaporator unit remains ice free.
Clean the sea water side of the condenser every 2 months.
What kind of metal must never be allowed to come in contact with Freon liquid or Freon gas and why?
Chromium, it will overheat.
Iron, it will be rapidly wasted by the Freon.
Aluminium, it dissolves in contact with Freon.
Copper, it has a harmful effect on the Freon.
What type of pump is referred to in the drawing as an “HS PUMP“?
Higgins-Simpson pump.
Hydraulic solenoid pump.
Hele-Shaw pump.
High suction pump.
What is the function of the valves “PR” fitted between the Port and Starboard cylinders?
To return any excess oil back to the suction of the pump.
To act as automatic by-pass valves when the steering gear is stopped.
To be opened to allow emergency steering.
To relieve excess pressure, absorbing shock and preventing damage.
When will the Hele-Shaw pump commence pumping action?
As soon as the electric motor is started.
As soon as the pilot system is started on the bridge.
As soon as point “Z” moves.
As soon as the telemotor pump is started.
When a command is given to this steering gear, what happens?
The spring “S” will be compressed or elongated.
The valves “PR” will activate, building up hydraulic pressure.
Point “X” will move, in turn moving point “Z“, controlling the pump delivery.
The hydraulic pumps will start.
What is the purpose of spring “S” fitted between point “Y” and the Trunion block of the steering gear?
To elongate and compress and keep point “Y” in place.
To absorb the clearance of the Trunion with the rod “X-Y“.
Ensuring flexibility by absorbing vibrations and clearances.
To avoid sudden movements and overload.
What is to be checked during a drydocking period to ensure that any upward movement of the rudder will be contained and damage to the steering gear will be avoided?
The rudder stock carrier bearing clearance.
The pallister bearing clearance.
The upper and lower pintle jumping bar clearances.
The pintle bearing clearances.
Which action of the steering gear pumps is feasible?
Pressure to cylinders A and D, return oil from B and C.
Pressure to cylinder A, return oil from D.
Pressure to cylinders A and B, return oil from C and D.
Pressure to cylinders A and C, return oil from B and D.
During normal operations, the command rod “C” pushes point “Z” and the control rod off centre so that the “HS” pumps start pumping and the steering gear moves. When will it stop moving?
When the command rod “C” stops moving.
When the command rod “C” moves in opposite direction.
When the trunion point “Y” pushes point “Z” back to its original position.
When the rudder angle indicator corresponds to the command.
What should you observe when inspecting the steering gear during your watch?
The oil level in the oil tank, see that there is no oil leakage.
The greasing of trunion and Pallister bearing is adequate.
No abnormal noise or vibrations, pump power consumption normal.
All of these.
This electric circuit is part of the Steering Gear Control System, in which the output is either 1 or 0 as either solenoid 1 or 2 is energized. It is an example of what kind of circuit?
A Wheatstone Bridge.
Two double resistor circuits balanced by the solenoids.
Two Potentiometers with amplifier relays.
A booster aggregate.
The first potentiometer of this electric command system is located on the bridge. By what mode might it be actuated?
By hand steering.
By push button steering.
By automatic steering via the auto-pilot.
By any of these steering methods.
What is the principle in which oil/water separation takes place in this cascade tank?
By separation frames.
By directional change and centrifugal action in triple-action.
By acceleration through chambers.
By acceleration and gravitation.
This steering gear telemotor system is drawn in the neutral position, rudder amidship. This means that:
Pump “P” is not pumping.
The double check valves are blocked.
The capacity control is at zero.
Neither solenoid “S1” or “S2” is energised.
What is the purpose of the double check valves fitted in this telemotor system?
To keep the rudder locked in the desired position.
To maintain the set pressure in the system.
To avoid oil blockage and stickiness.
To avoid pipe rupture due to sudden movements.
What is the purpose of the capacity control on the telemotor of a steering gear?
To keep the oil delivery quantity of the pump constant.
To keep the outlet pressure and capacity to react constant.
To keep the electric capacity between parameters (absorption).
To keep the oil delivery quantity to the telemotor ram constant.
How might this steering system be actuated?
By automatic gyro steering.
By push-button steering.
By hand steering.
By any of these.
What type of boilers are fitted (one only shown) to feed this turbine installation?
Scotch type boilers.
Water tube boilers.
Cochran type boilers.
Exhaust dissipation boilers.
Item “H” of the drawing indicates _____ of this turbine installation?
The distributor.
The steam filter.
The manoevring stand.
The steam reducer.
This installation consists of the following turbine combination:
A high pressure and a low pressure turbine.
A turbine system with ahead and astern manoevring capability.
The HP and LP turbine acting in tandem to one reduction gear.
All of these.
What are items “R” and why are they required?
Thrust bearings. To catch axial force and propel the ship.
Reducing block bearings. As turbine shaft support.
Coupling flanges. To allow disassemble of pinion gears.
Flexible couplings. To allow flexibility between HP and LP turbines.
Why is steam allowed to position – J‘ – of the turbine “J“?
It is the steam regenerating line.
It is the steam gland feeder line.
It is the steam to the astern turbine.
It is the parallel reduced steam line.
Why are components “S” required?
To transform rotating power into axial power.
To absorb the vibrations on the propeller.
To reduce high turbine speed to propeller speed.
To enable maximum fuel efficiency of the turbine installation.
Of what is this finned pipe a part?
Of an exhaust gas boiler steam generator.
Of an exhaust gas boiler economiser.
Of an exhaust gas boiler superheater.
Of any of the other options.
What is the purpose of the fins fitted on this steam piping?
As “Harmonica” piping, to make the piping flexible.
To increase the heated surface of the piping.
To allow for expansion with temperature differences.
To absorb the vibrations existing in the funnel.
After sometime, scale build-up is unavoidable in steam generating coils. How is it removed?
By cleaning with boiler tube brushes.
In the drydock by chemical engineers.
Bythe circulation of chemicals by small pump in port.
By flushing with the boiler water circulation pump.
How is this finned piping of an exhaust gas boiler fastened in the boiler wall?
It is caulked.
With a screwed coupling.
It is expanded.
It is welded.
How is the soot which will accumulate between the finned piping of an exhaust gas boiler removed?
By sand blasting in the drydock.
By high pressure water jet washing at 3 000 psi.
By chemical cleaning with pump in port.
Soot blowing at sea, water washing in port.
What would you do if water was found leaking at sea from the exhaust gas boiler and it is found to be from a leaking finned tube pipe from the steam generating unit?
Plug the pipe.
Plug the section/bank.
Put the entire steam generating bank out of commission.
Put the exhaust gas boiler out of commission.
By which unit is the combustion intensity in this boiler controlled?
By pressostat controlled fuel admission solenoids.
By the regulating valve “R“.
By the compound regulator.
By the position of the air flap.
What kind of burner would be fitted to this boiler?
A high speed jet burner.
A rotating cup burner.
A steam assisted burner.
A rotating nozzle burner.
What is the purpose of “S” fitted in the fuel admission line to the rotating cup burner of this boiler?
Emergency stop / Boiler failure cut-out for any reason.
Fuel admission by operation/Fuel block by stop/emergency.
Keeps fuel to burner open in normal firing mode via photocell.
All of these.
What is the main purpose of the photocell “P” fitted in the burner front casing?
To energise the fuel solenoid “S” when comustion is satisfactory.
To cut-out the boiler if water level is low.
To maintain the correct fuel/air ratio.
To detect firing of the pilot burner “PB“.
If the stand-by indicating light is energised on the control panel of this boiler burner, what does it indicate?
That the boiler is ready to be fired and no alarm conditions exist.
That an alarm condition extists.
That the pilot burner is in operation.
That the fuel is circulating and at the temperature ready to fire.
What is the function of the “Boiler Firing Switch” fitted on the control panel of this boiler burner?
To isolate the electric power to the control panel.
To open the fuel valve to the burner.
To change from stand-by to firing mode and fire-up the boiler.
To fire the boiler on manual in emergency.
What is happening when the “PURGING” indicating light is illuminated on the control panel of the boiler burner?
Purging air in boiler with flap “F” full open, solenoid “S” and “PB” closed.
Pump “P” is purging the fuel over pressure valve “R“.
Both air and fuel are admitted over “F” and “S“, ignition will start.
The boiler starts firing and the photocell will activate.
What burner equipment item operating when the ignition indication light is illuminated on this boiler’s control panel?
The fuel solenoid “S“.
The recirculating valve “R“.
The compound regulator “CR“.
The pilot burner “PB“.
The firing or the flame indicating light on the control panel of this boiler burner control panel shows that:
The pilot burner has fired.
Ignition is taking place.
Fuel is admitted to the main burner.
The boiler is operating normally.
The flame failure lamp on the control panel of this boiler burner will illuminate when:
The pilot burner fails to fire the main burner.
The flame is being smothered by water in the fuel.
The flame is dark due to incorrect fuel/air ratio.
Any of these faults.
What is the purpose of the restart button which you will find fitted to the control panel of this boiler’s burner?
To be pressed after low water cut-out.
To be pressed after restarting the feedwater pump.
To be pressed after flame failure.
To be pressed after the forced draught fan trips.
Which of the following conditions is a lock-out condition which will consequently illuminate the lock-out indicating lamp fitted to the control panel of the boiler burner light up?
Burner not correctly secured in position.
Low fuel oil pressure.
Low water level.
Any of these faults.
If you fire the boiler and it misfires repeatedly, indicating flame failure, what are you going to check first?
The boiler water level is at the correct level.
The fuel oil pressure and temperature are correct.
The photocell is clean in sight glass “G“.
The ignitor rods, clean the ignitor tips if necessary.
What do you think should be the temperature on thermometer “T” during normal operation of this boiler?
45 to 50 degree C.
60 to 65 degree C.
90 to 100 degree C.
125 to 130 degree C.
Prior to carrying out any work on boiler burners, you should isolate them. What is understood by this?
You must ensure that all electrical power supplies are shut off.
You must ensure that all fuel line valves are shut and fuel drained.
You must ensure that funnel uptake flap is closed.
All of these.
What is item “A” in the steam lay-out drawing?
The main 7,0 bar pressure reducing valve.
The 7,0 bar – 3 bar pressure reducing valve.
The 7,0 bar steam pressure relief valve.
The 3,0 bar steam pressure relief valve.
What is item “B” in this steam lay-out drawing?
The 7,0 bar pressure reducing valve.
The 3,0 bar pressure reducing valve.
The 7,0 bar manifold safety valve.
The 3,0 bar manifold safety valve.
What is item “C” in this drawing of the steam lay-out?
The 7,0 – 3,0 bar steam reducing valve.
The main steam reducing valve.
The main safety blow-off valve.
The 3,0 bar safety blow-off valve.
What is item “D” in this drawing of a steam lay-out?
A stem pressure reducing valve.
A steam balancing valve.
A blow-off valve.
A safety relief valve for the low pressure manifold.
The exhaust steam line of one of the consumers shown in this drawing will not return via the atmospheric condenser but direct via a water trap to the hot well. Which one?
Viscorator.
Purifiers.
ME heating.
Laundry.
In a split, reduced steam manifold, one manifold of pressure 7,0 bar, the other 3,0 bar. From which manifold are the returns taken direct to the hotwell?
From the 7,0 bar manifold.
From the 3,0 bar manifold.
From either the 7,0 bar or the 3,0 bar manifold.
Neither.
Why is there an air vent provided on the atmospheric condenser?
To blow off excess steam.
To avoid vacuum and keep atmospheric pressure.
To prevent the hotwell from steaming up.
To de-airate, to avoid corrosion.
What is the purpose of a steam trap, shown as “ST” on thre drawing?
To retain the steam and let the water pass.
To retain the water and let the steam pass.
To let steam and water pass only under atmospheric pressure.
To let water pass only under a vacuum.
What is this funnel like pipe fitted below the evaporating surface of the boiler water?
A feedwater funnel.
A blow down funnel.
A boiler water sample drain funnel.
A skimming plate.
When skimming-off, which valve will you fully open first and close last, whilst operating the other valve throttled?
The inner valve open first full and close last after operation.
The inner valve open first, the outer valve close last.
The outer valve open first and close last after operation.
The outer valve open first and the inner valve close last.
How do you carry out skimming operations on the boiler water?
Blow the water down until steam gushes out.
Slowly with feedwater pumps stopped.
Four to five repeated blows of about 5 seconds each.
When the boiler steam pressure has been reduced to atmospheric pressure.
Which main air compressor is normally used to top up the main air bottles?
Main air compressor No 1.
Main air compressor No 2.
Main air compressor No 1 or No 2.
Main air compressor No 1 and No 2.
During vessel manoeuvring, which Main Air Bottles are used?
No 1 Main Air Bottle.
No 2 Main Air Bottle.
No 1 or No 2 Main Air Bottle.
No 1 and No 2 Main Air Bottle.
What kind of filling valves are fitted on all the air bottles?
High pressure gate valves.
High pressure scew lift valves.
High pressure remote-control valves.
High pressure SD check valves.
What is item “M” fitted in the discharge line of the Instrument Air Compressor (IAC)?
An oil separator.
An automatic drain valve.
A moisture separator.
A drain valve.
What is the primary purpose of drain valves “D” fitted on all air bottles?
To blow the bottles empty if required.
To remove dirt from the bottle.
To remove water and condensate from the bottle.
To remove excessive oil from the bottle.
Which of the fittings listed below is NOT usually fitted on a compressed air bottle?
A thermometer.
A pressure gauge.
A safety valve.
A drain valve.
What is item “AD” in the main air supply line from the Instrument Air Bottle?
An air drain.
An air safety discharge valve.
An air dryer.
An air pressure safety device.
What are items “CP” fitted in the Working Air and Instrument Air supply lines?
Pressure capacity vessels.
Condensate pots.
Constant pressure vessels.
Pressure relief units.
Suppose you find that the safety valve of the Working Air Bottle blows off at a pressure in excess of 8,5 bar. Which of the causes listed below is NOT a possible cause for this lifting of the safety valve?
Compressor unloader is stuck in loading position.
Setting of cut-in / cut-out pressostat wrongly adjusted or defective.
Pressure reducing valve from main air bottle defective or stuck.
Insufficient air consumption by the working air consumers.
In what kind of machinery do you find this type of valve fitted?
Main engine scavenge air manifold.
Ventilation air ducts.
Air compressors cylinder heads.
Auxiliary diesel crankcase door explosion relief valves.
What is part No. 3 of this valve?
A valve flexible disc.
A feather spring plate.
A disc connecting plate.
A suction/discharge plate disc.
How do you to make this valve air tight during overhaul?
By fitting O-rings on seat plate 5.
By machining the seat of valve disc 4 and seat plate 5.
By fitting cupper gaskets to the valve body.
By lapping and polishing valve disc 4 and seat plate 5.
How is this type of valve kept in place in the cylinder head of an air compressor?
It is screwed into the valve space of the cylinder head.
It is secured to the cylinder head by bolts.
It is fitted in a valve housing which is bolted by a flange onto the cylinder head.
It is kept in place by a collar flange, bolted on the cylinder head.
How is the valve shown here made air tight in the cylinder head of the compressor?
No joint, both faces lapped to each other.
An O-ring of perbunan is fitted between valve and seat.
A general purpose joint is fitted.
A copper gasket is fitted.
Why is it important that the exhaust gas boiler bypass flap to exhaust is operated when the main engine is running at reduced or manoeuvring speed on Heavy Fuel Oil?
To ensure proper firing of the engine.
To ensure starting of the engine.
To avoid backpressure on the engine at low speed.
To avoid corrosion in the exhaust gas boiler.
If the auxiliary seawater pump “AS” fails, which pump should be used to cool the condensers?
Fire Pump “FP“.
General Service Pump “GSP“.
Hydrophore Pump “HP“.
Main Sea Water Pump(s) “MS“.
If the reefer condenser pump “PP” fails, which pump would you use to supply cooling water to these reefer condensers?
Fire Pump “FP“.
General Service Pump “GSP“.
Auxiliary SW PUMP “AS”.
Any of these pumps may be used.
If the auxiliary condenser is not in use for any operation at sea, which pump should be used to cool the atmospheric and dumping condensers?
The General Service Pump “GSP“.
The Fire Pump “FP“.
The Reefer Condenser pump “PP“.
By the Main Seawater Pump “MS“.
If the dirty oily water mixture fills chamber 1 of this separation bowl, where will the clean oil be found?
Item 2 in the bowl.
Item 3 in the bowl.
Item 4 in the bowl.
Between item 2 and item 4.
What liquid substance is present in chamber 1 of this oil-water separator?
Clean oil.
Water.
Dirty oil.
Oil/water mixture.
If a dirty oily/water mixture is entering chamber item 1 of this separator, where will the dirt settle?
With the liquid item 3.
On the bottom item 4.
With the liquid item 2.
On the separation plate between liquids 2 and 3.
Which force is acting to separate water from oil in this separator?
Centrifugal force.
Gravitational force.
Kinetic energy.
Chemical potential.
Where will the dirt collect which is separated from the oily water mixture in this Sharples separator, shown left?
On the inner mantle of the cylindrical bowl.
On the oil/water separation plate.
On the bottom of the cylindrical bowl.
Near separating plate flushed off with water.
Where will the dirt collect from the oily water mixture if separated by the centrifugal disc type separator, shown right?
On the cylindrical surface of the bowl.
On the bottom of the bowl.
On the top separation plate between oil and water.
In between the discs.
The Sharples separator, shown left and the Disc type separator, shown right, both run at high RPM. But which runs at the highest speed?
Both run at the same RPM.
The Sharples runs at a higher RPM.
The DISC type runs at a higher RPM.
It depends for which kind of oil gravity either is used.
The Disc type oil separator can usually separate water from oil when processing oils between which density ranges?
0,845 to 0,965.
0,78 to 0,98.
0,87 to 0,95.
0,84 to 0,945.
If insufficient water sealing is present (blue colour) in the bowl of this separator, what will be the effect?
Water will discharge with the clean oil.
Insufficient oil will be pumped through the purifier.
The purifier will overflow oil on the water side.
The high temperature alarm will activate.
What should be the thermal efficiency of this kind of tube heat exchanger?
Between 32 and 46 %.
Between 70 and 78 %.
Between 86 and 93 %.
100 %.
If the heated medium of this heater is oil and the heating medium is steam, excess steam supply or insufficient oil flow could cause excessive _____ in the heater.
Deformation.
Pitting.
Corrosion.
Carbon formation.
Why is a heavy flywheel (item number 7) required on this starting air compressor?
To absorb the large torsional forces (2 cylinder).
To absorb the vibrations due to high speed (900 – 720 RPM).
To accelerate evenly when starting.
To avoid stalling when drain and unloaders close.
Suppose the rated delivery pressure of this main air compressor is 25 bar, what would be the delivery pressure of the first stage cylinder?
12,5 bar.
15 bar.
8,3 bar.
5 bar.
Which parts of a refrigeration plant are shown here?
Compressor, dryer, evaporator.
Compressor, oil separator, evaporator.
Compressor, collector, condenser.
Compressor, oil separator, condenser.
What type of condenser is fitted to this refrigeration unit?
A fin coil air fan cooled type.
An air duct cooled type.
A sea water cooled type condenser.
A fresh water cooled type condenser.
To which type of installation would you find these refrigeration components fitted?
Reefer ship cargo installations.
Ships accommodation air conditioning plants.
Engine control room air conditioning plants.
Small domestic refrigeration units.
How is the capacity of this type of refrigeration installation controlled?
By the compressor unloader.
By the expansion valve.
By the solenoid valve.
No capacity control is fitted.
How are the components of this type of refrigeration system joined together?
By flared piping connections.
By screwed piping connections.
By flanged piping connections.
By soldered piping connections.
What is the correct name of part number 1 shown here?
A thermo-balanced expansion valve.
A thermodynamic expansion valve.
A thermostatic expansion valve.
A thermo-controlled expansion valve.
What size of refrigeration installation is shown here?
A large installation (reefer cargo).
A medium size installation (accommodation aircon).
A smaller size installation(provision rooms, small air conditioning units).
A very small cabinet refrigerator unit.
What kind of medium is found in the line to which safety blow-off valve part No 3 is fitted (red line)?
Hot superheated gas of high pressure.
Hot saturated gas and oil.
High pressure wet gas.
Resaturated high pressure gas.
What is part No 5 of this refrigerator compressor drawing?
A cylinder head spaces plate.
A valve plate.
A distance collar.
A cylinder head gasket plate.
What kind of material is NEVER used for the pistons of a refrigeration compressor?
Cast Iron.
Light alloy.
Perlite steel.
Pure aluminium.
How is lubrication arranged in this refrigeration compressor?
By attached crankcase lub. oil pump.
By splash lubrication.
By a cylinder lubricator.
By independent lubricating pump.
If the suction and delivery valves are closed for test and the compressor is losing gas pressure rapidly (indicating a leak), which part would you suspect first?
The valve plate gaskets.
The crankcase door gasket (fitted on block No 1).
The flanged pipe gauge connections.
The shaft seal (item No 7).
What is part No. 7 of this refrigerated compressor?
A flexible type shaft seal.
A carbon ring type shaft seal.
A chemical resistant box seal.
A spring tensioned bellow seal.
Which type of suction and delivery valves woul be fitted in this type compressor?
A cylindrical combination suction/delivery valve.
Vane type valve plates riveted on valve plate.
One each cylindrical suction and delivery valve.
Spring controlled poppet valves.
In what capacity range are refrigeration compressors of this type found (shaft input expressed in Kilo Watts)?
300 W to 1,5 kW.
2,5 kW to 7,5 kW.
5 kW to 15 kW.
25 kW to 65 kW.
Is capacity control feasable on this compressor? If yes, how would it be arranged?
No, capacity control system cannot be fitted.
Yes, capacity control valve acts on the unloader by suction pressure.
Yes, by throttling the suction valve.
Yes, by setting the expansion valve.
What is part No. 3?
The sterntube.
The stern.
The rudder.
The transom.
What is the shaft called to which the propeller is fastened?
The main engine shaft.
The stern shaft.
The intermediate shaft.
The tail shaft.
How is the propeller fitted onto its shaft, so as to avoid it from slipping?
It is bolted on the flange of the drive shaft.
It is locked into slots on the drive shaft.
It is keyed onto a tapered shaft.
Wires are fitted through the securing holes of shaft and propeller.
What part is fitted under the propeller cone?
The propeller seal.
The propeller locking bar.
The propeller nut.
The rope guard.
What metal is the stern tube usually lined with?
Aluminium brass.
Gunmetal.
White metal.
Phosphor bronze.
How would this stern tube bearing be lubricated?
By grease.
By water supply.
By a closed lubricating oil system.
It is self lubricating.
If refrigerant gauges are calibrated in Absolute Corresponding Temperature, can these gauges be used for any refrigerant in any refrigerating system?
Can be used for Freon 12 or Freon 22 only.
Can be used for any refrigerant.
Can be used for any refrigerant except AMMONIA.
Are calibrated for only one refrigerant.
What is the shape of stern tube seals (forward and aft)?
They are flat gaskets between flanges.
They are square in form and diagonally cut.
They are round in form and in one piece (O-ring type).
They are lip seals and in one piece.
Which are the stern tube bearing parts on this type of stern tube?
The cylindrical steel tube aft.
The forward and aft plummer blocks.
The forward and the aft bearing bushes (liners).
The cylindrical steel tube with white metal lining and oil supply system.
What is the purpose of the 3-way cock part No. 7 in the stern tube oil circuit?
To remove air from the system.
To fill oil in the system.
To drain the oil from the stern tube and sample.
To change over from main to forward stern tube sealing circuit.
Why is the stern tube header tank fitted above the sea water level?
To ensure lubrication of the after stern tube seal.
To ensure lubrication of the forward stern tube seal.
To avoid oil being spilled overboard.
To avoid sea water entering the stern tube.
Steam produced by a boiler whose temperature is above that corresponding to its pressure is referred to as _____?
Dry steam.
Regenerated steam.
Bled steam.
Superheated steam.
What liquid is present in collecting point 11 at the bottom of the fresh water generator evaporator shell?
Ejector water.
Brine.
Fresh water.
Sea water.
What is the purpose of the sea water pump item No. 13?
To supply sea water to the condenser.
To drive the air ejector of the evaporator.
To supply water to be evaporated.
To cool the evaporator.
What is the source of energy used to convert salt water into fresh water in this fresh water generator?
The vacuum and ejector pump item 13.
The seawater pump supplying the evaporating water item 14.
The ejector pump and seawater pump combined.
The waste heat from the main engine.
How is a vacuum created in the fresh water generator?
By the condensing effect in the condenser.
By pumping or educting out the brine.
By the vapour eductor driven by the ejector pump.
By the differential temperature of fresh and sea water.
What is item No 9 shown here fitted between evaporator and condenser of this fresh water generator?
A desalinator unit.
A water filter assembly.
A water deflector.
A heating cap.
What is the required salinity of the fresh water produced as drinking water onboard?
Below 20 ppm.
Below 50 ppm.
Below 7 ppm.
Below 2 ppm.
What is the maximum salinity allowable (in ppm) for water produced by this fresh water generator when it is to be used in medium pressure water tube boilers?
20 ppm.
15 ppm.
7 ppm.
2 ppm.
If the FW generator is producing water with salinity of 5 ppm and is changed to produce water of 2 ppm, this is mainly achieved by _____ .
Slowing down production by opening the vacuum breaker valve.
Decreasing production by lowering fresh water supply from ME.
Decreasing sea water cooling to the condenser.
Throttling sea water feed supply to the evaporator.
What should be the level in the sight glass of the accumulated fresh water in the fresh water generator?
One inch from the bottom.
Two inches from the top.
Half level.
Between one fourth and half level.
What is the ideal temperature difference between inlet and outlet on this evaporator?
2 to 4 degree C.
4 to 6 degree C.
6 to 8 degree C.
8 to 12 degree C.
What type of pump is the distillate water pump, item No 7, and at what pressure is it discharging the liquid?
Vane pump, under pressure.
Centrifugal pump, under vacuum.
Centrifugal pump under pressure.
Vane pump, under vacuum.
Prior to starting the distillate pump, item No 7, it is necessary to make sure that _____ in order to avoid the pump running dry.
Water is visible in the sight glass of the evaporator.
The discharge valve of the pump is shut.
The vacuum in the evaporator is still minimum.
The evaporator is full and under presuure.
When starting up a fresh water generator it often happens that the distillate pump fails to pump out the produced water. This could be caused by _____ .
The vacuum being too high in the fresh water generator.
The fresh water generator being too high.
An air leak on the shell and grease needs to be applied.
The pump is drawing in air through a leaking shaft seal.
When taking over the watch as duty engineer, what would you check first, before inspecting the plant condition?
The engine room bilges.
The log book entries from the previous watch.
The fire alarm monitoring equipment.
The Chief Engineer’s standing orders and special instructions.
Whilst taking over of the watch, besides verifying standing orders and the actual condition of the plant, tank levels and operations, what other important matter should you verify?
That the bilges of all wells pumped.
What is the firefighting equipment in state of readiness.
If any workis being performed in the engine room.
Where are the leakages in pipes, tanks and equipment.
In reefer installations the cooling effect is produced by lowering the pressure of the refrigerant so that ______ .
The liquid will be able to absorb heat from the surroundings.
The liquid will be able to expand to gas.
Its boiling point is reached and it will be able to absorb heat.
It will be able to be compressed again and give off heat.
In this nozzle/flapper assembly (part of a pneumatic control system) at what distance away from the nozzle does the flapper need to be moved in order not to have any influence on the NBP (nozzle back pressure)?
h = 0,4 D.
h = 0,25 D.
h = 0,5 D.
h = D.
What is the meaning of the pressure indicated by NBP on this nozzle/flapper assembly?
Normal Basic Pressure.
Nominal Balance Pressure.
Nozzle Back Pressure.
Nozzle Balance Pressure.
What is the most common reason for malfunctioning or erratic functioning of a pneumatic nozzle/flapper assembly?
The nozzle is worn out.
The flapper is broken or distorted.
Dirty air passages of restrictor and nozzle.
Oil or moisture in the back pressure line (NBP).
If the flapper is pushed against the nozzle so that h = 0, what will the reading of NBP become?
0 psi.
20 psi.
3 psi.
15 psi.
This characteristic shows that only linear part a-b can be used. This means that the normal effective travel of the flapper is only _____ for the full measuring range.
0,005 mm.
0,01 mm.
0,05 mm.
0,10 mm.
What pneumatic control device is shown here?
A pneumatic flapper/nozzle assembly.
A pneumatic controller.
A pneumatic amplifier.
A pneumatic booster aggregate.
Which important pneumatic control accessory is shown here?
A pressure regulator.
An amplifier.
An nozzle / flapper assembly.
A transmitter.
What is the most common reason for malfunctioning of a pneumatic amplifier?
Gasket No 8 blown.
Diaphragma No 7 bursts.
Valve stem No 6 defective.
Internal passages blocked by oil mixed with dirt.
This shows a pneumatic control unit which forms the basis of pneumatic control engineering. It is _____?
A pneumatic transmitter assembly.
A totaliser or summator unit.
A nozzle/flapper assembly with amplifier.
A pneumatic basic controller unit.
These small pneumatic pipes are connected to the different parts of pneumatic system so they can be easily dismantled, using _____?
Clamps with bellow packing.
Retainer springs and silicon.
Plugs and O-rings.
Sleeves and copper gaskets.
Which part shown here is the nozzle in this pneumatic assembly?
Part No. 2.
Part No. 3.
Part No. 4.
Part No. 5.
What will be the existing pneumatic pressure in connecting pipe item No 6 from flapper nozzle assembly to the pneumatic amplifier?
Between 2 and 2,75 psi.
Between 3 and 15 psi.
20 psi.
Between 0 and 20 psi.
What is the output pressure of this pneumatic amplifier?
7 to 15 psi.
3 to 15 psi.
15 to 25 psi.
3 to 20 psi.
What pneumatic device is shown here?
A proportional controller.
A proportional transmitter.
A feedback amplifier.
A feedback controller.
What is the name of the bellow P, which indicates its purpose?
Absorbing bellow.
Equalising bellow.
Feedback bellow.
Lifting bellow.
If we shift the nozzle/flapper assembly to the left so that the length of “a” is half of length “b“, to what level will L’ rise before it stabilizes?
Twice the height from level L.
Half the height from Level L.
1/4th the height from level L.
Four times the height from level L.
What is the level difference between L and L’ called in this process?
The span.
The range.
The amplification.
The offset.
The working pressures used by pneumatic control components are between 3 and 15 psi. What are the equivalent currents used by electric control equipment?
Between 0 and 20 mA or 4 and 20 mA.
Between 10 and 50 mA or 15 and 50 mA.
Between 20 and 60 mA or 25 and 75 mA.
Between 0 and 5 or 3 and 9 mA.
Alternator temperature indicators often giving readings in degrees Fahrenheit. If a reading is 80 degrees F, how many degrees Celsius is this?
23,8.
26,6.
29,2.
32,7.
The two valves shown on the left of this picture are called flat valves and give a high throughput for a small lift in height. They are mostly used for ______ .
Process stability, for a certain percentage in lift changes the throughput by the same percentage.
Self correcting flow valve, by changing pressures in the system the throughput the same.
Open – close regulation.
A stop (zero flow) valve.
The two valves shown in the centre of the drawing are ______ .
Pear shaped valves.
Flat top valves.
Linear valves.
Equi-percentage valves.
The two valves on the left of this picture are _____, the two valves on the right are ______ valves.
Flat top, linear.
Pear shaped, equi-percentage.
Linear, curved.
Linear, equi-percentage.
In addition to pressure, Freon gauges are calibrated in:
Absolute pressure.
Absolute corresponding temperature.
Superheated gas temperature.
Saturated gas temperature.
In a refrigeration system the method of reducing the capacity without reducing the compressor speed is called:
Hot gas by-passing.
Short cycling.
Hot pressure by-passing.
Low pressure by-passing.
When the evaporator coils are located directly inside the refrigerated space the system is known as _____ .
An indirect system.
A low pressure system.
A double evaporator system.
A direct system.
An abnormally hot suction line in a refrigerating plant may be due to ______ .
Insufficient refrigerant.
Too much refrigerant.
Too much oil in circulation.
High latent heat of evaporation.
Low alkalininity of boiler water or the presence of free oxygen, or both may result in ______ .
Scale.
Corrosion.
Foaming.
Priming.
Flash point of oil is the temperature at which ______ .
It will ignite in the cylinder.
Condensation occurs.
It should be stored in a pressurised tank.
Flammable vapours form at its surface.
Kinetic energy of a body is due to its ______ .
Position.
Temperature.
Motion.
Horsepower.
Which of the following is a unit of work?
Pounds per minute.
Kilograms per minute.
Kilogram meters.
Foot-pounds per minute.
Power is the work done ______ .
Per unit of acceleration.
Per unit of force.
Per unit of time.
Per unit of distance.
Which of the combustible elements of fuel oil is a major source of boiler corrosion?
Oxygen.
Sulphur.
Hydrogen.
Carbon.
A hydrazine test is conducted on boiler water to check for _____ .
Sulphates.
Excess oxygen.
Phosphates.
Nitrates.
Saturated steam produced by a boiler should be separated from moisture ______ .
By the superheater.
By cyclones.
By passing through the dry pipe.
In the turbine steam trap.
The Specific Heat of water is ______ .
One.
10 degree F.
100 degree C.
Greater than 212 degree F.
The unit of measure used to express the chloride content of boiler water is ______ .
PPM.
gms per cc.
pH.
micro-ohm.
What do you call the valve that prevents steam pressure from exceeding the allowable working pressure?
The safety valve.
The steam regulator valve.
The steam pressure reducing valve.
The main steam stop valve.
The relief valves in a fuel oil service system discharge to either the service pump suction or to the _____ .
Recirculating line.
Simplex fuel oil strainer.
Settling tanks.
Slop retention tanks.
Testing boiling water for chloride content will indicate the amount of _____ .
Solids in the water as a result of sea water contamination.
Phosphate present in the water.
Dissolved solids in total present in the water.
Alkalinity level.
Under normal conditions, how is the superheated steam outlet temperature regulated?
By diverting part of the flow through the desuperheater.
By varying the combustion air.
By regulating the water supply temperature.
By replacing the burners nozzles.
Which of the following is the neutral PH value?
0.
7.
9.
7,5.
Steam which is in physical contact with the boiling water from which it is being generated is called _____ .
Unsaturated steam.
Pure steam.
Wet steam.
Saturated steam.
The atmospheric pressure is accurately indicated by a _____ .
Bourdon gauge.
Hygrometer.
Manometer.
Barometer.
When a fresh water generator condenses water vapour into water it:
Emits latent heat of fusion.
Emits latent heat of evaporation.
Absorbs latent heat of fusion.
Absorbs latent heat of evaporation.
The heat used to change a liquid to a vapour is called “latent heat of _____“.
Fusion.
Evaporation.
Absorption.
Transmission.
A refrigerant gives up heat when it:
Evaporates.
Condenses.
Vaporizes.
Boils.
The lowest temperature obtained in a refrigerator system is the temperature of the:
Evaporator coil.
Liquid in the condenser.
Receiver cooling water temperature.
Liquid in the evaporator.
Refrigerating or cooling effect is produced by:
The pressure change of the refrigerant.
The boiling refrigerant changing to a vapour.
Increasing the pressure of the refrigerant.
Lowering the pressure of the refrigerant.
The two main types of refrigeration system evaporators are called:
Wet and dry.
Dry and flooded.
Finned and tube.
Short and extended.
The greatest decrease in the temperature of a refrigerant is at the:
Expansion valve.
Evaporator.
Condenser.
Receiver.
When Freon is leaking from a refrigerating system, a halide torch flame will turn:
Blue.
Yellow.
Green.
Orange.
A receiver in a refrigeration system is used to:
Separate oil from the refrigerant.
Store the refrigerant.
Cool the hot gases.
Condense the refrigerant.
When used with reference to a refriferation or air conditioning system ambient temperature is the:
Temperature of the space being cooled.
Temperature of the air outside the spce being cooled.
Temperature difference between the space being cooled and the outside temperature.
Temperature of the machinery space.
The temperature of a refrigerant is highest just before it enters the:
Receiver.
Condenser.
Evaporator.
King valve.
Moisture in a refrigeration system will cause a:
Low discharge temperature.
High suction pressure.
High suction temperature.
Faulty expansion valve.
The cooling effect in a refrigeration system is produced by:
Lowering the pressure of the refrigerant.
Increasing the pressure of the refrigerant.
Boiling the refrigerant.
Pressure changes to the refrigerant.
Excess refrigerant in a refrigeration system is normally removed from the:
Discharge side of the evaporator.
Suction side of the system.
Compressor crackcase.
Charging connection of the system.
The indications of a faulty refrigeration compressor valve are:
Low head pressure-high suction pressure.
Any of these.
Continuous running.
Gradual or sudden decrease in capacity.
High latent heat is desirable in a refrigerant so that:
Smaller compressors can be used.
Smaller pipes can be used.
It will boil at low temperature.
A small amount of refrigerant will absorb a large amount of heat.
When adjusting compressor V-belts:
Make them as tight as possible.
Allow 12 mm slack.
Make the belt just tight enough to turn the pulley.
Always replace the belt first.
What will happen if brine in a refrigeration system has a high specific gravity?
It will freeze.
It will crystallize.
Nothing will happen.
It will solidify.
In a refrigeration system, a precooler is sometimes installed between the:
Compressor and the condenser.
Condenser and the expansion valve.
Expansion valve and the evaporator.
Evaporator and the compressor.
Frost appearing at the high pressure side of a thermostatic expansion valve in a refrigeration system is probably caused by:
The refrigerator box being too cold.
A dirty or iced-up expansion valve.
The condenser being too cold.
The head pressure being high.
In all refrigeration installations, the cooling effect is produced in the:
Compressor.
Evaporator.
Condenser.
Liquid reservoir.
An automatically controlled Freon-12 compressor will stop when the:
Expansion valve closes.
Expansion valve opens.
Solenoid valve closes.
Solenoid valve opens.
If the compressor discharge in a refrigeration system becomes frosted, the probable cause is:
The expansion valve being improperly set.
The refrigerant flooding back.
The compressor cuts out too frequently.
A faulty king valve.
In the refrigeration system, the low pressure side would be from:
The outlet of the expansion valve to the suction of the compressor.
The discharge of the compressor to the inlet of the expansion valve.
The outlet of the condenser to the inlet of the expansion valve.
The outlet of the condenser to the outlet of the expansion valve.
When used in operating accomodation air conditioning systems, humidity is a measure of:
Temperature.
Evaporation.
Latent heat.
Water vapour content.
What is the other name of the brine-circulating system of refrigeration?
Closed system.
Expansion system.
Indirect system.
Direct system.
In a refrigeration system, a fluid that serves only as a heat carrier is called the:
Condensing refrigerant.
Secondary refrigerant.
Vaporizing refrigerant.
Primary refrigerant.
When ordering an expansion valve for a refrigeration system which of the following information is necessary?
Size and pressure.
Size, tonnage, temperature and pressure.
Pressure and temperature.
Size and tonnage.
What is this component?
A pressure reducing valve.
A exhaust valve.
A safety valve.
A non-return valve.
What is part No. 1 called?
A shaft.
A spring.
A spindle.
A guide.
What is part No. 7 called?
A spring cap.
A valve cover.
A spring adjuster.
A spring retainer.
What is part No. 5 called?
A valve disk.
A valve disk holder.
A valve seat.
A spring supporter.
What is part No. 6 called?
The spring retention piece.
The spring cover.
The valve lid.
The spring guide.
What is “simmer” in a safety valve?
First leakage before the valve opens.
A metallic hammering noise.
A hissing sound indicating that a safety valve is leaking.
A failure of a safety valve to re-seat.
How often should the operation of a boiler safety valve be checked?
At each annual survey.
At each dry dock.
At regular intervals.
Only when the electronic checking system fails.
What is component “A” called?
The evaporator.
The condensor.
The pump.
The compressor.
What is component “B” called?
The evaporator.
The brine tank.
The condensor.
The suction tank.
What is component “C” called?
The expansion valve.
The suction valve.
The pressure regulator.
The condensor valve.
What is component “D” called?
The condensor coil.
The expansion coil.
The evaporator coil.
The superheater coil.
What is component “G” called?
The freon tank.
The water tank.
The compressor receiver.
The liquid receiver.
What are the four processes in a refrigeration cycle?
Suction / Compression / Expansion / Power.
Compression / Condensation / Expansion / Evaporation.
Evaporation / Expansion / Implosion / Condensation.
Condensation / Evaporation / Cooling / Compression.
What is the function of the expansion valve?
To regulate the flow of refrigerant to the evaporator.
To reduce the pressure of the liquid refrigerant.
To increase the pressure of the liquid refrigerant.
To regulate the flow of refrigerant to the evaporator and to reduce the pressure of the liquid refrigerant.
What is the function of the evaporator?
Transferring heat from the substance being cooled.
Evaporating humid air in the room or area being cooled.
Act as a heat exchanger between the hot refrigerant and the cooling medium.
To recycle used refrigerant.
What is the function of the compressor?
To compress hot air.
To pump the liquid stored in the auxiliary refrigerant tank.
To compress the refrigerant.
To compress hot air and to pump the liquid stored in the auxiliary refrigerant tank.
Which part in this diagram is the discharge valve?
Part B.
Part E.
Part G.
Part I.
What is significant about an indirect refrigeration system?
It measures temperature in directly.
It uses a secondary refrigerant like brine to do the cooling.
It has an indirect circulation of cooling medium.
It uses ammonium instead of Freon as cooling gas.
What is the function of the dehydrator in a refrigeration system?
To reduce risk of corrosion in the brine tank.
To take away humid sediments in the suction valve.
To absorb moisture usually present in the refrigerant.
To reduce moisture in the compressor house.
Which part is the Adjusting bolt?
No 1.
No 2.
No 5.
No 6.
What part is the diaphragm disc?
Part 6.
Part 3.
Part 2.
Part 4.
Which part is the spring house?
Part 3.
Part 4.
Part 5.
Part 6.
What is Part No. 7 called?
The disc.
The diaphragm.
The plate.
The rubber membrane.
When taking over the engine room watch, you should verify that the steering gear is:
Operational and the ship is on course.
Vibration free operation without oil leaks and that the unit is well greased and lubricated.
Not running in overload or not overheating.
Well ventilated.
When taking over the engine room watch you should verify that the pallister bearing carrying the rudder stock:
Is well greased and that no water ingress is noticeable.
Has no jumping clearance.
Has no axial clearance.
Has sufficient clearance on the gland packing and is not scoring the liner or the seat plate.
When taking over the engine room watch you should ensure that the stern tube oil gravity tanks:
Contain sufficient oil to maintain level during your watch.
Contain oil to the correct level mark to ensure that there is no oil loss via the stern tube.
Are changed-over from high to low or vice versa as required.
Are at the required temperature and if hot, more water should be added to the stern tube.
When taking over the engine room watch you should ensure that the stern tube seal:
Is supplied with cooling fresh water.
Is supplied with cooling sea water.
Is not leaking.
Has not shifted inside the liner.
When taking over the engine room watch you should ensure that the stern tube shaft is:
Not running hot.
Exactly “hand warm“.
Not vibrating and not running hot.
Not twisted.
When taking over the engine room watch you should ensure that the intermediate shaft:
Is polished and that the polishing mats are in place.
Is adequately greased.
Is at engine room temperature.
Is vibration free.
When taking over the engine room watch you should ensure that the intermediate shaft bearings are:
At the desired temperature, that adequate oil is flowing and that cooling water supply is on.
Not overheating, not leaking oil and that no white metal is spotted.
Not running hot, the cooling water is not blocked and the oil is not dirty.
Not hot or making any unusual noise and that the cooling water valve is open.
When taking over the engine room watch, you should check that the engine room supply fans:
Are well greased.
Are covered by dirt screens.
Are not overheating.
Are running vibration and noise free.
When taking over the engine room watch you should check that the engine room fan’s intake grids or intake filters:
Are free of dirt or obstacles.
Are properly bolted in place.
Are cleaned with oil and grease remover.
Are secured by wire mesh.
When taking over the engine room watch, what should you check in the engine room workshop when no one is working there?
That the fire alarm is switched off and that the electric power is switched off.
The fire alarm is switched on, the electric power to equipment switched off and any gas bottle valves are closed.
That the lights are switched off and the valves of the welding gas bottles are closed.
That all lockers are closed, that workshop is locked and the lights switched off.
When taking over the engine room watch, what are you to check and verify concerning the bilges and any accumulated water?
The amount of water in the bilges, the Chief Engineer’s standing orders and check for any accumulation and its source.
Check accumulation source and piping and check when the bilges were last pumped.
Check dryness of bilges, water in accumulation tank (bilge tank) and verify whether bilges were pumped.
Check from where the water or oil is originating and when the bilges were last pumped.
When taking over the engine room watch, what should you check concerning the operational heavy fuel oil purifier?
The flow-through capacity, the temperature on the inlet, the bearing temperature and the Ferodo coupling.
The water seal (tank), the crankcase oil level ,the flow-through capacity, the fuel inlet temperature, the overflow pipe and the back pressure.
The attached fuel pump bearings, the fuel back pressure, the inlet temperature and the suction strainer.
The Ferodo coupling, the bearing temperature, the crankcase oil level, the pump bearing temperature and the setting of the timers.
When taking over the engine room watch, what should you check concerning the heavy fuel supply to machinery and boilers?
That the settling tanks and the daily service tanks are full.
That the settling tanks and daily tanks are at least for 75 % full.
The daily and settling tank levels, the purifier line-up and throughput, in order to ensure at least sufficient fuel supply to last your watch.
The temperatures of the settling tanks and daily tanks.
When taking over the engine room watch, what should you check on the heavy fuel oil daily and settling tanks in addition to the supply capacity?
Air supply to the quick closing valves, the tank vent screens, the remote or distance gauging system.
Compare the remote gauging system with tape sounding readings, drain the moisture off.
Verify the temperatures, check the tank vent screens, unclog the distance reading system.
The tank temperatures, drain the collected water off and verify if the quantity of water is normal.
When taking over the engine room watch, what should you check concerning the operational lubricating oil purifier?
Check whether throughput is on maximum, check the water seal, check the overflow/water flow off pipe, check inlet temperature and back pressure.
Check whether throughput is minimum, check the overflow pipe, check whether the alarm is activated.
Check the setting of the timers, check the inlet temperature, the back pressure, the bearing temperatures.
Check the Ferodo coupling, the bearing temperatures, the inlet temperature and the back pressure.
When taking over the engine room watch, what should you check on all engine room fresh water expansion tanks?
That the temperatures are normal and the tanks are not steaming up.
That the levels of the tanks are normal and if any abnormal additions during previous watches.
That the automatic filling or float systems are in good operational order.
That the chemical concentration of the water is correct.
When taking over the engine room watch, what should you check concerning the hot well of the condensate/feedwater system?
Whether correct level, no excess of make-up water being supplied and that there is no steaming up.
Whether the cooling water supply is sufficient and that the level is satisfactory.
Whether the heating coil is in operation and that the automatic filling valve is working to satisfaction.
Whether the filters are cleaned and that the chemical concentration of the water is correct.
When taking over the engine room watch, what should you verify concerning the sea cooling water supply system?
The suction pressure and the discharge pressures.
The cooling water system line setting and the sea water pressures to the different components.
The cleanliness of the filters and the correct sea chests are in operation.
The sea water temperature and the sea water pressure.
When taking over the engine room watch, what should you check on the operational boilers when the exhaust gas boiler alone is providing the heat supply?
The soot blowers, the economiser and the boiler furnace.
The boiler water circulating pumps, the feedwater pumps and the feedwater temperature.
The boiler water level, the steam pressure and the exhaust gas change over flap position or coil percentage used.
The economiser and superheater temperatures and the steam pressure.
When taking over the engine room watch, what should you check on the oil fired boiler if this is in operation?
Steam pressure, water level, flame brightness, cleanliness of the photocell glass plus fuel temperature and pressure.
Furnace temperature, uptake gas temperature and smoke indicator.
Feedwater temperature, fuel oil pressure, CO2 content of uptake gases and flame brightness.
Feedwater temperature, steam pressure, water level, fuel pressure and CO2 content of uptake gases.
When taking over the engine room watch, what should you check concerning the main compressed air system?
That the valves to the deck air fore and after are open.
That the air compressors are in a state of readiness with correct oil level in the crankcase and air bottles are drained.
That the branch lines to the working and instrument air are correctly opened and at the desired pressure of 7,5 kg/cm2.
That the non-return valves from compressors to bottles are correctly set.
When taking over the engine room watch, what should you check concerning the fresh water generator?
The vacuum percentage and the sea water temperature.
The difference between sea water inlet and outlet on the condenser and the fresh water inlet and outlet on the evaporator.
The sea water feed supply pressure, the eductor pressure, the fresh water level in the collector and fresh water pump back pressure.
All of the operating parameters and the fresh water production in the last 4 hours.
During your watch you notice that the salinity of the fresh water produced by the fresh water generator has gone up together with the output. You notice too that sea water temperature has dropped. What should you do?
Throttle the sea water flow to the condenser.
Throttle the fresh water flow to the evaporator.
Increase the flow to the eductors.
Increase the opening on the vacuum breaking valve.
What are the most common faults resulting in failure to raise adequate vacuum in a fresh water generator?
Insufficient flow to eductors (pump pressure or eductor back pressure), leaking fresh water pump shaft seal, leak on casing or cover.
Dirty condenser, fresh water pump impeller wear rings worn, vacuum breaker valve worn.
Dirty evaporator, feed reducing valve blocked, by-pass valve of the fresh water to evaporator leaking, vacuum breaker faulty.
Reflector plate corroded, feedwater supply pipe blocked, blocked or dirty tubes in evaporator or in the condenser.
What do you think is the most common cause of poor performance of fresh water generators?
Scaled/dirty heat exchangers, in particular the evaporator.
Underperformance of ejector and/or fresh water pump(s).
Worn brine or vacuum nozzles.
Internal corrosion of structural components of housing.
Here is a list of activities which amongst other things you will have to perform when starting a fresh water generator. Which list is in the correct order?
Supply fresh water to evaporator, start fresh water pump, start ejector pump, supply coolwater to condenser.
Supply coolwater to condenser, supply fresh water to evaporator, start fresh water pump, start ejector pump.
Start ejector pump, supply cooling water to the condenser, supply fresh water to the evaporator, start fresh water pump.
Start fresh water pump, start ejector pump, supply cooling water to condenser and fresh water to the evaporator.
If when you start up a purifier it does not come up to the desired revolutions, or it takes too long a time to come up to the required revolutions, you should change the:
Purifier ball bearings.
Friction pad linings.
Gravity disc.
O-rings and seal set of the bowl.
The most common reason for overflow on purifiers is:
The wrong gravity disc.
Dirt between purifier plates.
Water seal broken.
Ball bearings worn out.
When the density of purified oil has increased, you should:
Increase the temperature and decrease the gravity disc inside diameter.
Increase the temperature and increase the gravity disc inside diameter.
Decrease the temperature and decrease the gravity disc inside diameter.
Decrease the temperature and increase the gravity disc inside diameter.
During start up of a purifier, how will you notice when the bowl has reached the required revolutions?
The crankcase rotating indicator will turn fast.
The vibrations on the purifier will increase.
The purifier will make a humming noise.
The starting amperage will drop sharply to normal (1/3 to 1/4) from the starting current.
Caution must be taken when handling purifiers since errors can cause great danger. Handle with due caution is required in operation, dismantling, assembling, inspection, maintenance. This is because:
Danger of electrocution from the electric power supply to driving motor, various control solenoids and other required operational controls is great.
Oils and fuels cause fire and explosion when handled carelessly. This danger is increase because the fuels and oils fed to purifiers is heated.
Static electricity may be generated if parts are wrongly assembled causing explosion within the purifier.
Purifier bowls revolve at very high speed generating great centrifugal forces, careless handling causes danger of disintegration.
If some part of a purifier bowl assembly is defective, what action should be taken?
Have it repaired on board if it can be done.
Send it to a qualified workshop for repair.
Order the specific bowl spare part.
Contact the makers for guidance and act on their advice only.
The starting/ accelerating current of a purifier is ____ % of the normal operating current.
50.
100.
150.
250.
The time interval for automatic sludge discharge from purifiers must be chosen correctly. In general the more frequent the interval the better. Howeve too short intervals are inefficient and too long intervals:
Will also give bad efficiency.
May result in overflowing of the purifier due to clogging with dirt.
Will result in difficult desludging due to adhesion of sludge.
May result in water seal depletion.
As a rule of thumb, the time interval set for automatic desludging of diesel oil purifiers should be ____ hours.
1 to 2.
2 to 3.
4 to 5.
6 to 8.
As a rule of thumb, the time interval set for automatic desludging of 380 cSt heavy fuel oil purifiers should be ____ hours.
1 to 2.
2 to 4.
4 to 6.
6 to 8.
As a rule of thumb, the time interval set for automatic desludging of 180 cSt heavy fuel oil purifiers should be ____ hours.
2 to 3.
1 to 2.
4 to 6.
6 to 8.
As a rule of thumb, the time interval set for automatic desludging of lubricating oil purifiers used on crosshead type engine sumps should be ____ hours.
1 to 2.
2 to 4.
4 to 6.
6 to 8.
The factors which determine the selection of the size of gravity disc for a purifier are:
The bowl speed, the oil temperature and throughput.
The specific gravity of the oil and the oil temperature.
The oil temperature, the sludge content and the specific gravity.
The oil temperature, the water and sludge content and the specific gravity.
Oil purifiers can be used for purifying as well as for clarifying operations. The clarifying operation is referred to as:
The single phase liquid-liquid operation (water from oil).
The 3 phase liquid-liquid-solid operation, separating light from heavy liquids, as well as solids from light as from heavy liquids.
The 2 phase liquid-solid operation, separating dirt from oil.
The 2 phase solid-liquid operation, separating dirt from water and oil.
The usual mode of series operation of two heavy fuel oil purifiers refers to:
Two identical machines being put separately from settling tank to daily tank at half the feed rate through each purifier.
Two identical machines being put from settling tank to 1st purifier, hence to second purifier, at half the throughput each purifier.
Two identical purifiers being used for heavy fuel oil as well as for diesel oil, by changing line system and gravity discs.
Two identical machines being operated in series, the first as purifier, the second in line as clarifier with same throughput.
If the oil flows out on the heavy liquid (water) side of a purifier, the most likely reason is:
That the gravity disc inside diameter is too big, or that the oil temperature has dropped, increasing the density of the oil.
That the revolution of the bowl has slowed and the electric motor is in overload.
That the amount of closing water for the bowl is insufficient.
That the operating water for the bowl has been turned off or the containing tank is empty.
If the oil flows from the sludge outlet on an oil purifier, the most likely reason for this is:
That the relief valve of the gear-type supply pump is working.
That air is being sucked into the suction piping of the lub oil pump.
That defects have developed in the vertical shaft parts or otherwise that the rubber plate has hardened.
That the bowl has not been closed correctly, there is a fault in main seal ring, pilot valve or water supply for closing the bowl.
When water is found mixed in the light liquid (oil) outlet of an oil purifier, the most likely reason is:
Excessive supply of sealing water, feed rate too high and water outlet of oil clogged.
Defects in the horizontal shaft parts.
Water in the gear case.
That the relief valve of the oil supply attached pump has been set too high, causing overload.
If you find that the feed rate of an oil purifier (its throughput) has reduced, the most likely reason for this is:
Insufficient delivery from the gear pump, the pump’s relief valve is passing, a leaking suction pipe or blocked suction filter.
That the wrong type of gravity disc is fitted, the oil temperature is incorrect or the heater is blocked.
That the amount of sealing water of the bowl is insufficient or the containing tank is empty or shut-off.
That the revolution speed of the bowl has slowed or the electric motor is operating in overload.
If the electric motor on an oil purifier is overloaded or has tripped, the most likely reason is:
That the rubber plate has hardened causing excessive supply of sealing water.
That there are defects in the driving system, clutch, gears or bearings.
That the discharge pressure on the light liquid outlet is set too high, or the oil temperature has dropped.
That the amount of sealing water is insufficient or the sealing water timer is wrongly adjustment.
When abnormal vibrations or sounds are noticed from an oil purifier, the most likely cause is:
That the oil seal for the horizontal shaft is worn or damaged.
That the bowl has failed causing contact with non-rotating parts or defects in horizontal or vertical shaft parts have occurred.
That the gravity disc is the wrong size and/or oil inlet temperature is too low.
That the water outlet of the bowl is blocked causing imbalance in the purifier bowl.
When inspecting purifier crankcase oil you find that the oil has emulsified or that the level of oil has dropped. The most likely reason is:
That the bowl revolutions have dropped and the purifier is working in overload.
That water is leaking in or oil is leaking out via the oil seal of the horizontal shaft.
That the safety joint of the oil pump is broken.
The bowl is leaking water on the main seal ring.
If during your engine room watch you hear the boiler water level alarm sound and you notice low water level, but the feedwater pressure is normal, what should you do first?
Shut the boiler main steam stop valve.
Shut-off the steam heating to the tank consumers.
Open the by-pass feedwater check valves.
Start another feedwater pump.
If during your engine room watch the steam supply or steam pressure should fall for some reason, what should you check first?
The fuel oil and lub oil purifiers.
The boiler water level.
The hotwell level.
The viscosity of the heavy fuel oil to consumers.
If during your engine room watch, without any previous warning or alarm, the oil fired boiler trips due to “flame failure“, what should you check first?
The cleanliness of the photocell.
The fuel oil temperature.
The fuel oil pressure.
The boiler water level.
The reason for an oil fired boiler uptake emitting dark smoke could be:
A faulty or dirty boiler nozzle tip or boiler fuel rotating cup.
The fuel / air ratio adjustment incorrect.
A restriction in the free air supply to the boiler fans, perhaps the engine room vent fans are not running.
Any of these.
Before starting soot blowing operations on boilers, you should ensure that:
The safety valves are set correctly.
The boiler water level is at maximum.
The bridge is informed.
The boiler is manually fired.
Boiler water chemical additives should be supplied to the boiler via:
The hotwell.
The hotwell through the chemical dosing pump.
The boiler circulating water inlet through the chemical dosing pump.
The chemical dosing line.
Why is it dangerous to add chemicals directly into the hotwell?
Danger from splashes on the eyes and skin.
It creates “hot spots” of chemical concentration in the feedwater which can cause structural harm.
The vapours developed are dangerous when inhaled.
The chemical concentration causes harm to the feedpumps.
The main danger of feeding cold feedwater into a boiler is:
That it causes dangerous steam pressure drops.
That it causes stress in the vicinity of the inlet piping as well as corrosion.
That it can cause implosions.
That it causes oxygen depletion in the feedwater filling line.
The use of boiler economisers:
Increases the boiler evaporating surface.
Increases the overall boiler thermal efficiency.
Decreases the steam consumption.
All of these.
Before swinging-out a boiler burner for maintenance or cleaning, you are to ensure that:
The electrical power is switched off.
The fuel is isolated.
The boiler furnace is well ventilated or blown through.
All of these.
Before raising steam in a boiler, you should ensure that:
The feedwater check valves are open.
The boiler water circulation valves are open.
The steam main stop valve is open.
The air vent cock is open.
If there is a very sudden and large increase in steam consumption, how will the boiler water level behave?
It will drop drastically.
It will increase drastically.
It will at first drop suddenly, then increase drastically.
It will at first rise suddenly, then drop drastically.
After a total black-out with an automatic power supply system, what is the correct sequence for restarting the essential pumps once the power is restored?
Main sea water pump, jacket CW pump, piston CW pump, lub oil pump, injector CW pump.
Jacket CW pump, piston CW pump, injector CW pump, lub oil pump, main sea water pump.
Main lub oil pump, jacket CW pump, piston CW pump, injector CW pump, main sea water pump.
Injector CW pump, main sea water pump, jacket and piston CW pump.
Water whith a pH value of 7 is referred to as:
Alkaline.
Neutral.
Acid.
Basic.
Hardness in feed water is mainly attributed to salts of these metals:
Potassium and Iron.
Magnesium and Calcium.
Sodium and Aluminium.
Sulphur and Vanadium.
All the ferrous components of a ship will sustain strong corrosive action in the presence of:
Acid waters.
Alkaline waters.
Steam.
Turbulent water.
The reason why two-stage starting air compressors are used in preference to single stage compression is that:
The power absorption by single stage compression would be too high.
The temperature developed by single stage compression would be too high.
The starting current of a single stage compressor would be too high.
The friction in a single stage compressor would be too high.
From where should a boiler water sample be taken for testing?
From the water space.
From the steam space.
Lowest part of the boiler drum.
From the drain cock.
After boiler inspections and surveys, what is the final test carried out by the surveyor in order to accredit the safety valves and boiler mountings?
Check the valves for corrosion.
Check the valve spindles for cracks.
Check safety valve blow-off pressure with boiler under steam.
Check the condition of valves and valve seats.
On resuming normal purification after automatic de- sludging you frequently experience a high temperature alarm. What will you do to avoid reoccurrence?
Increase capacity through the purifier.
Lower the set point of the oil temperature.
Fit or adjust (increase) time delay on the high temperature alarm.
Decrease capacity through the purifier.
If oil is found in the auxiliary boiler water, what action would you take other than isolating the leak?
Stop any chemical treatment.
Dose the coagulant.
Skim and blow down the boiler.
Dose the coagulant, skim and blow down the boiler.
When an overhaul of a compressor is completed and the compressor is to be started for a test run, it is important to:
Check the direction of rotation.
Check that an open discharge line exists through to the receiver.
Check that all air receiver outlets are closed during the test run.
Check the maximum pressure of the capacity on run-up.
How do you test the probes for the 15 ppm monitor?
By immersing in oil.
By checking in air and immersing in water.
It is only necessary to clean them.
They have to be changed, onboard testing is not possible.
What should you do if a purifier starts to vibrate badly?
Check the vibration alarm.
Try to increase the flow.
Try to decrease the flow.
Stop the purifier immediately.
Why is it important to follow a maintenance schedule for purifiers?
To improve the purifier’s efficiency.
To prevent serious damage to main components.
The only maintenance necessary is cleaning of the bowl.
To comply with company regulations.
What will you do if the plate exchanger leaks when returned to service after cleaning?
Tighten more.
Close the valves.
Dismantle the exchanger, check or renew packings.
Reduce pressure.
On the air compressor crankcase there is a small valve that lets off pressure. What should be done if oil is present with the air?
Lower the sump oil level.
Check the clearance in the bearing.
Block off the valve.
Overhaul the compressor unit.
A leak from the gland of a centrifugal pump is found to be excessive. The correct procedure is to:
Fit over size packing to the stuffing box.
Tighten the gland as much as possible until the leakage stops.
Regularly pump out the bilge well to which it is draining.
Re-pack the stuffing box loosely with the correct size packing at the earliest opportunity.
At what interval should boiler water testing take place?
Every eight hours.
Every fortnight.
Every day.
Every week.
When opening a plate cooler for cleaning, how should the bolts be removed?
Fully slacken and remove top ones first, then the middle and then the bottom ones.
Fully slacken and remove the middle bolts first, then the top and then the bottom ones.
One by one, clockwise.
One by one, anti-clockwise.
The plate heat exchanger is separated for cleaning, what should you do if the plates are thick with scale or other organic material?
Change the plates.
Put the plates in water with cleaning chemicals. Use soft a brush or high pressure cleaner with care.
Use a high pressure cleaner with abrasives.
Use a wire-brush or metal scraper to clean the plates.
For a low pressure boiler, testing shows the water chloride level to be 1 000 PPM. What action would you take?
No action needed.
Blow down boiler and check condenser for leakage.
Increase chemical dosage.
Decrease chemical dosage.
What happens if the rudder is moved in a heavy sea?
The main pressure relief valves lift.
The hydraulic motor absorbs the shock.
The over pressure is absorbed by system accumulators.
The telemotor pump prevents movement by increasing the hydraulic pressure.
If the gauge glass indicates no water level in the boiler what should be your first action?
Check the operation of the feed pump.
Check the feed tank water level.
Shut off all the burners.
Blow down the gauge glass.
When starting an air compressor, why is it necessary for the unloader to be activated before the drain valves are closed?
So the pumping action can blow the drains through.
To avoid the safety valves blowing.
To avoid air blowing in the bilges.
To prevent the compressor from tripping.
Which fuel quality is measured in seconds Redwood?
Flashpoint.
Specific Gravity.
Viscosity.
Ash content.
In a provison room refrigeration system what would be the most likely cause of high compressor discharge pressure?
Failure of the expansion valve.
Ice formation on the evaporator coils.
Overcooling of the evaporator return.
Inadequate condenser cooling.
How is the quality of the distilled water from a fresh water generator improved?
Increasing the shell vacuum.
Decreasing the seawater feed to the evaporator.
Slowing down the output of the evaporator.
Decreasing the jacket water flow to the evaporator.
What would be fitted to relieve excess refrigeration compressor pressure?
Pressure relief valve to atmosphere.
Pressure relief valve to suction line.
Bursting disc to compressor suction.
Bursting disc to condenser inlet.
How are boiler tubes secured in the end plates?
Welded.
Expanded.
Screwed.
Screwed collar on the outside of the plate.
What purpose is the fuel oil settling tank?
To settle out water.
To settle out sludge.
To settle out suspended solids.
To settle out all impurities.
What damage could be caused to the boiler by raising steam too quickly?
Damage to furnace refractory.
Excess soot deposits on cold tube surfaces.
Distortion of the shell due temperature differential.
Leaking tubes where expanded into the shell.
What action would you take if the boiler water Chloride readings are too high?
Add more chemical to the feed water.
Blow down the boiler regularly until readings are acceptable.
Drain and refill the feed water tank.
Increase frequency of testing.
What is the desired salinity of the fresh water produced as drinking water onboard?
Below 20 ppm.
Below 50 ppm.
Below 10 ppm.
Below 5 ppm.
What is meant by “Isothermal” expansion?
Expansion during which heat must be added.
Expansion at constant temperature.
Expansion during which heat is lost.
Expansion at constant pressure.
Which of the following is the most likely cause of a restriction at the expansion valve?
Oil being carried over with the refrigerant.
Blockage in the filter/drier unit.
Moisture in the system.
Insufficient gas charge.
Which is the least harmful of these refrigerants?
Freon 12.
Freon 22.
Ammonia.
Carbon Dioxide.
What of the following is the most damaging to riveted mountings?
Leakage through the rivets.
Rusting of the rivet heads.
Raising steam too quickly.
Chloride levels too high.
What action should you take in the case of an boiler uptake fire?
Operate soot blowers to extinguish fire.
Increase air supply to burn fire out.
Shut off burners, shut down fans and close off air supply.
Shut down burners but maintain fans to clear fire.
How is temperature controlled in a steam oil heater?
Steam supply pressure reduced.
Steam inlet valve throttled.
Oil flow increased.
Steam outlet valve throttled.
What is the usual pressure adjustment method on boiler safety valves?
Set bolt and locknut.
Removable shim packs.
Different rate springs.
Set spring pressure with machineable adjustment rings.
What is the function of a Viscotherm in the fuel system?
To control the fuel temperature.
To regulate the fuel pressure.
To control viscosity by altering temperature.
Controlling fuel pressure and temperature.
What slows the rudder movement when the requested position is reached?
The steering wheel transmitter.
The rudder control receiver unit.
The hunting gear feedback signal.
The rudder telemotor control.
What regular maintenance is required on the boiler burner?
Renewing of the electrodes.
Overhauling of the shut-off valves.
Cleaning of the burner tips.
Cleaning and resetting of the air register.
What liquid is present in the collecting point at the bottom of the evaporator?
Ejector water.
Brine.
Fresh water.
Sea water.
What service is most suitable for the use of rotary compressors?
High pressure, low volume.
High pressure, high volume.
Low pressure, low volume.
Low pressure, high volume.
What is the first action when flashing up a boiler?
Start up the water feed pump.
Purge furnace with air.
Clean the burner nozzle.
Lower the oil pressure.
What percentage CO2 in the uptake is present in good combustion?
10 %.
12 %.
15 %.
25 %.
In a single stage air compressor what is the maximum practical delivery pressure?
7 bar.
3 bar.
10 bar.
15 bar.
What percentage CO2 in the flue gases would indicate correct combustion?
5 %.
12 %.
7 %.
20 %.
What does the sight glass indicate in a refrigerator system?
Operation of the expansion valve.
Condition of the filter drier unit.
Adequate refrigerant charge.
Efficiency of the condenser.
What compressed air supply valve must always remain open?
Air to ship’s whistle.
Air to deck services.
Air to starting air lines.
Air to workshop service.
What is the purpose of the scum valves on the auxiliary boiler?
Removal of scum from the feed tank water.
Removal of scum from the drains observation tank.
Removal of scum from the boiler water surface.
Draining the boiler water to the bilge.
What best describes the boiler “easing gear“?
Remote operation of stop valves.
Manual lifting arrangement of safety valves.
Reduction gearing to facilitate opening of main stop valves.
Feed control unit.
In an electrically controlled hydraulic system what do the electrical controls replace?
The hunting gear.
Hydraulic control valves.
Hydraulic telemotor system.
Rudder feedback signal.
What is the correct S. G. for brine used as a secondary refrigerant?
1,05.
1,1.
1,25.
1,5.
What term is used to describe access holes to the boiler drum?
Inspection holes.
Drum access holes.
Manholes.
Furnace inspection panels.
What is the primary purpose of drain valves fitted on all air bottles?
To blow the bottles empty if required.
To remove dirt from the bottle.
To remove water condensate from the bottle.
To remove excessive oil from the bottle.
What precaution must be observed when fitting new anodes to heat exchanger sea water spaces?
PTFE tape applied to the plug threads to enable easy removal.
Ensure the anode is as close as possible to the tube plate.
Ensure no damage is caused to the exterior surface of the anode.
Ensure good, clean contact is made between anode and Cooler body.
What is the effect if the boiler fuel oil temperature is too low?
Flame failure.
Fuel delivery pump cutting out.
Flame impingement and refractory damage.
Blocking of fuel filters.
What boiler mountings must be dismantled for inspection during survey?
Safety valves.
Gauge glass & valve components.
Feed water check valves.
All boiler mountings.
What condition would necessitate blowing down the boiler?
Water level too high.
Chloride readings too high.
Steam pressure too high.
PH reading below 7 ppm.
What is the maximum salinity for water produced by a fresh water generator when it is to be used in water tube medium pressure boilers?
20 ppm.
15 ppm.
7 ppm.
2 ppm.
What is the normal maximum starting air pressure?
50 bar.
40 bar.
30 bar.
20 bar.
A hydrazine test is conducted on boiler water to check for:
Sulphates.
Excess oxygen.
Phosphates.
Nitrates.
Why are some boiler tubes not plain cylindrical?
For extra strength.
To facilitate gas flow.
To give a greater heating.
To reduce scale formation.
How is a vacuum created in the fresh water generator?
By the condensing effect in the condenser.
By pumping or ejecting out the brine.
By the vapour ejector driven by the ejector pump.
By the differential temperature of fresh and sea water.
Upon what is the movement of the rudder dependant, when a helm order is given?
The degree of opening of the hydraulic bypass valve.
On the adjustment of the feedback rod connection.
On the distance the hydraulic control lever is moved by the floating link.
On the hydraulic pressure setting of the relief valves.
What is the purpose of the automatic unloading valve when fitted to the air start compressor?
Prevent the pressure relief valves from lifting.
Prevent damage to the valves when starting.
Avoid the first stage relief valves lifting when starting.
Avoid high starting current on the motor.
What equipment Operates on a Rankine Cycle?
Diesel engine.
Petrol engine.
Gas turbine.
Steam power plant.
Where is the filter/drier unit fitted in the refirgerant line?
Between condenser and expansion valve.
Between expansion valve and evaporator.
On the compressor discharge line.
At the evaporator inlet.
In the formula P.L.A.N. what is “N” for a 4 stroke diesel engine?
RPM.
RPM/120.
RPM/30.
RPM/60.
What is a telemotor system?
Hydraulic actuation of steering rams.
Transfer of steering signals from wheel to steering gear.
Hand actuation of steering gear.
Steering gear feedback system.
What does the telemotor receiver unit control?
Main steering motor control voltage.
Hydraulic operating pressure.
Speed of rudder movement.
Hydraulic pump delivery.
What is the most dangerous effect on the boiler burner of water in the fuel?
Poor combustion.
Extinguishing of burner flame.
Damage to furnace refractory.
Loss of boiler efficiency.
Where on the main starting air receiver would a fusible plug be fitted?
On the underside.
Adjacent to the filling valve.
Next to the relief valves.
On the manhole door.
On what part of the air compressor does the unloader act and in what way?
It keeps the SUCTION VALVES open.
It keeps the SUCTION VALVES closed.
It keeps the DELIVERY VALVES open.
It keeps the DELIVERY VALVES closed.
What is the function of the relief valves fitted between main hydraulic cylinders?
To return any excess oil back to the suction of the pump.
To act as automatic by-pass valves when the steering gear is stopped.
To be opened to allow emergency steering.
To act as safety valves to absorb shock and avoid damage.
What is always fitted in instrument air supply lines?
An oil separator.
An automatic drain valve.
A moisture separator.
A drain valve.
When should you make sure that loose gear in machinery space is properly secured?
Prior to leaving port.
When you are warned by the bridge of bad weather.
After completion of every job.
At all times.
What would be a normal operating pressure of an auxiliary boiler?
6-9 bar.
Below 5 bar.
15-20 bar.
Above 20 bar.
What is the most important purpose of the auxiliary boiler on a modern diesel engine vessel?
Domestic water heating.
Accommodation heating.
Heating of heavy fuel oil.
Fresh water generation.
What is the function of the expansion valve in the refrigeration circuit?
To allow the expansion of the high-pressure gas before the condenser.
To reduce the pressure of the liquid refrigerant.
To increase the pressure of the liquid refrigerant.
To regulate flow and reduce the pressure of refrigerant to the evaporator.
What could be the effect of excess steam or reduced oil flow in an oil heater?
Deformation of tubes.
Eroding of tube ends.
Corrosion of tubeplates.
Carbon formation on tubes.
In the case of air-cooled compressors what form does the cooler take?
Honeycombed radiator.
Vertical flattened pipes.
Finned circular pipes.
Horizontal box section pipes.
What is the purpose of air release valves on boiler shell?
To expel air when raising steam.
To expel air when filling the boiler.
To vent the boiler when shut down.
To check when steam is being produced.
In a single motor electrical steering system what supplies the main steering motor?
Hydraulic power pack.
Electrical supply from a local motor/generator.
Mains electrical supply.
Hydraulic power delivered by the main steering motors.
What is the most likely source of Chloride contamination in the boiler feed water?
Feed water tank.
Fuel heater.
Drains cooler.
Accommodation heating.
In tankers an alternate hydraulic oil supply must be automatically connected for the steering system within what time?
45 seconds.
2 minutes.
3 minutes.
5 minutes.
How is an air conditioning compressor normally unloaded?
By holding open the discharge valves.
By throttling the suction valves.
By holding open the suction valves.
By throttling the suction valves.
In a conventional rudder system when will least power be required to move the rudder?
With the vessel stationary.
With vessel moving astern.
Vessel full ahead at service speed.
With vessel moving slowly ahead.
What daily test should be carried out on boiler water?
Dissolved oxygen.
Dissolved nitrogen.
Chloride content.
Sulphite content.
What is the state of refrigerant leaving the evaporator?
Low-pressure liquid.
High pressure gas/liquid mixture.
Gas at high pressure.
Gas at low pressure.
What does the term volumetric efficiency refer to?
Mechanical efficiency.
Pumping efficiency.
Thermal efficiency.
Overall efficiency.
On the fresh water generator why is a baffle plate fitted between evaporator and condenser?
To cool the vapour.
To prevent carry over of brine.
To maintain the vacuum inside the shell.
To maintain the evaporator temperature.
What is the most dangerous effect of scale build up in the boiler water space?
Loss of boiler efficiency.
Overheating and deformation of furnace.
Damage to feed water valves.
Flame impingement on the furnace walls.
Why is the presence of oil particularly dangerous in starting air lines?
It may carbon up and choke the lines.
The high oxygen content makes it very explosive.
It may cause sticking of the air start valves.
It could affect the operation of the relief valves.
What type of filling valve is fitted on all air bottles?
High pressure gate valves.
High pressure butterfly valves.
High pressure remote-control valves.
High pressure SD check valves.
What is the possible consequence of too high a water level in the boiler?
Feed pump cutting out.
Carry-over of the boiler water.
Insufficient steam generation.
Boiler shutting down.
What does wheel movement control in an entirely electric steering system?
Hydraulic transmitter.
Current supplied directly to the electric steering motor.
The electrical balance of the wheel and steering motor rheostats.
Current to the steering gear motor/generator.
What is the steering system oil tank within the steering pedestal?
Main hydraulic system header tank.
Lubrication tank for the steering gear linkage.
Reservoir for the telemotor system.
Header tank for the auto pilot control system.
What provides power to the hydraulic emergency steering system?
Battery power to the entire steering system.
Emergency generator running main hydraulic pumps.
Manual operation of main pumps.
Accumulators in the hydraulic system.
Which of the following is a system for controlling the steering electrically?
Graduated stepper motors.
Ward Leonard System.
AC-DC rectification.
Compass repeater motors.
When testing boiler water for chlorides, what does the test indicate?
Solids in the water from sea water contamination.
Phosphate present in the water.
Total dissolved solids present in the water.
Alkalinity level.
What is the main advantage of vacuum production of fresh water in the fresh water generator?
Less possibility of contamination.
Low cost of distillation equipment.
Simpler to operate.
Utilizes waste heat from the main engine.
How is “water hammer” best avoided in steam lines?
Fully open main stops and line valves when raising steam.
Open line valves as quickly as possible.
Ensure lines are drained and open valves slowly.
Leave main stops and line valves open when shutting down the boiler.
In a hydraulic telemotor steering system movement of the wheel:
Transmits electrical signal to the hydraulic actuator valves.
Controls the main hydraulic pumps.
Controls movement of the transmitter electric motor.
Controls movement of the transmitter pistons.
What is meant by radial vane type steering system?
Hydraulic pumps are vane type pumps.
Telemotor is vane type operation.
Rudder movement is via vanes mounted onto rudderstock.
Steering is via rotating propulsion unit.
When commencing operation of the fresh water generator, what must you ensure before starting the distillate pump?
Water is visible in the sight glass of the condenser.
The discharge valve of the pump is shut.
The vacuum in the evaporator is still minimum.
The pump is primed via the priming line.
If purifier does not attain full speed what could be the likely cause?
Out of balance.
Bowl incorrectly assembled.
Motor running too slow.
Drive clutch slipping.
Why are cylindrical boiler end plates of dished shape?
Increased water capacity.
Better accommodates the furnace.
Stronger than flat plates.
Easier access to manhole doors.
What is the plate material used in sea- water, plate heat exchangers?
Stainless steel.
Cupro Nickel.
Titanium.
Bronze.
Which of the following is a rotary compressor?
Starting air compressor.
Emergency air compressor.
Diesel engine charge air compressor.
Control air compressor.
How far from the coast is it permitted to use Low-pressure evaporation to produce drinking water?
20 miles.
5 miles.
30 miles.
12 miles.
What maintenance is required for an “Auto-Kleen” knife type filter?
Remove element and hand clean.
Periodically remove sludge from the filter base.
Remove element and renew.
Back flush the filter.
What is the most important aspect of communication with the Bridge?
Ballasting operations, cargo hold bilge pumping.
Executing of orders from the bridge.
Executing orders from and issuing warnings to the bridge.
Operation of fire fighting and life saving equipment.
What is the state of the refrigerant at the condenser outlet?
High-pressure gas.
High pressure liquid.
Low pressure liquid.
Gas/liquid mixture at evaporator pressure.
What shutdown device might be fitted on air compressors?
High air pressure.
Low first stage pressure.
Over speed.
High delivery temperature.
Why should refrigerator compressor oil be stored in small capacity drums?
Ease of handling.
Ease of stowage.
Refrigerator oil is hygroscopic and should not be stored in part full drums.
Only small quantities are required.
Why is it necessary to produce fresh water from seawater?
To save cost.
To ensure purity.
Limited shipboard storage.
To make use of waste engine heat.
What factors influence the vacuum inside the shell of a fresh water generator?
The temperature of the fresh water heating the evaporator.
The temperature of the sea water cooling the condenser.
The pressure of the ejector water on the vacuum ejector.
All of the given options.
What controls the boiler feed water delivery?
Feed water tank level.
Steam demand.
Water level controll of feed pump delivery.
Water level control of feed water inlet valve.
In a refrigeration system what effect has the solenoid stop valve?
Electrically shuts down the compressor.
Shuts off the refrigerant on the compressor suction line.
Operates the stop valve on the compressor discharge line.
Stops the refrigerant from entering the evaporator.
When used as secondary refrigerant what determines the brine SG required?
Amount of brine in circulation.
Carrying temperature of the cargo.
Type of primary refrigerant in use.
Capacity of refrigerant compressors.
What term is used for unequal distribution of burner spray in the boiler furnace?
Flame impingement.
Furnace distortion.
Combustion air imbalance.
Unequal firing.
If fuel is dripping from the water outlet of the purifier what could be the cause?
Delivery pump not functioning correctly.
Discharge pump not functioning correctly.
Purifier needs cleaning.
Gravity ring is of the wrong size for the fuel being purified.
Which is the correct sequence after starting the compressor?
Compressor on load followed by drain valve closing.
Drain valve closes before compressor starts delivering.
Drain valve only operates on shutdown.
Drain closing and compressor starts delivering together.
What type of valves are normally found in air compressors?
Plate or disc valves.
Poppet valves.
Slide valves.
Piston controlled ports.
Why are anodes fitted to the seawater side of heat exchangers?
To afford corrosion protection for the system pipes and valves.
To prevent scaling of the tubes and tube plates.
To afford corrosion protection to the sea water side of the heat exchanger.
To prevent the formation of marine growth in the water spaces.
What mountings must be tested daily on steaming boilers?
Main feed water check valves.
Boiler blow down valves.
Safety valve easing gear.
Water level indicators.
Can leaking stern tube seals be replaced when the vessel is afloat and if yes, how?
No, they can only be replaced in dry-dock.
Yes, with divers working under water whilst the forward seal is blanked.
Yes, ballast the ship until the stern tube is clear of the water.
Yes, but only the forward seal can be replaced.
What would your first action be if the boiler feed pump stopped?
Shut down the boiler burners.
Change over to the auxiliary feed pump.
Check the gauge glass readings.
Shut the main stop valves.
Why is the stern tube header tank fitted above the sea water level?
Ensure lubrication of the after stern tube seal.
Ensure lubrication of the forward stern tube seal.
To prevent bilge water entering the stern tube.
To avoid sea water entering the stern tube.
What material is the boiler shell constructed from?
High grade Molybdenum steel.
High tensile steel.
Good quality low carbon steel.
High carbon steel.
When would both steering gear motors be run together?
When manoeuvring in confined areas.
When at anchor in a confined anchorage.
When on passage to minimise wear.
In the tropics to overcome the lowering of the oil viscosity.
What is the function of the boiler Low Level alarm?
Increase the feed water supply.
Sound alarm and shut down boiler burner.
Sound low level alarm.
Reduce the oil supply to the boiler burner.
What liquid is used in thermometers for extremely low temperatures?
Mercury.
Alcohol.
Inert gas.
Pentane.
What is the purpose of hunting gear when referring to a hydraulic steering system?
To transmit hydraulic pressure.
To control hydraulic motor swash plate movement.
Provides feedback to the pump control.
Limits the speed of the rudder movement.
Where is the temperature of the refrigerant highest?
At the expansion valve.
At the compressor discharge.
At the condenser outlet.
At the compressor suction.
What is the main advantage of plate heat exchangers?
Easier to clean.
Cheaper to install.
More efficient and take up less space.
Require less maintenance.
Is it possible to blow down a steaming boiler?
No, this should never be carried out.
Only in an extreme emergency.
Yes but steam pressure should be maintained.
Yes but never allow the level to disappear from the gauge glass.
Suppose the delivery air pressure of a compressor is 30,0 bar. Which service could this compressor be supplying?
A service air compressor.
An instrument air compressor.
A working air compressor.
A starting air compressor.
In steam power plant what supplies the energy input?
The condenser.
The turbine.
The boiler.
The economiser.
Which of the following would indicate the steam trap in the drawing was operating correctly?
Inlet warm and drain hot.
Inlet and drain hot are both hot.
Inlet and drain are both cold.
Inlet hot and drain warm.
Swirlyflo tubes would be used in which application?
Waste heat economiser tubes.
Auxiliary boiler smoke tubes.
Heat exchanger tubes.
Refrigerant condenser tubes.
