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Preparation of the Cargo Spaces, Stowage and Securing of Cargoes on the Vessel

The ships presented by the carrier for loading shall be in a seaworthy condition, and the cargo spaces shall be prepared to receive the cargo (distribution, stowage, securing).

Preparation of the ship shall include:

  1. checking fitness of the cargo spaces for the particular cargo and inspection of the pipelines passing through the cargo spaces;
  2. examination of cargo handling gears for their serviceability;
  3. inspection of reliability of closures, which will be inaccessible after loading, and closures, which shall be closed as appropriate;
  4. examination of the water-level alarms in bilge wells and also bilge system for their operable condition;
  5. inspection of the fire systems and equipment for their operable condition;
  6. examination of the hatch covers and the hydraulic system of the hatch covers driving-gear for leakproofness.

All residues of previously earned cargoes shall be cleaned from cargo spaces, specifying, that the order of cleaning depends on the kind of cargo to be carried.

Prior to the carriage of construction materials, metal products, vehicles, unpackaged and other cargoes, which cannot be influenced by dust, odours etc. dry cleaning of the cargo spaces should be carried out.

The cargo spaces intended for the carriage of foodstuff and vegetable goods, cotton, fabrics and other manufactured goods in small-sized parcelling or packages shall be washed, dried and ventilated prior to loading. In case of presence of odours, the cargo spaces shall be deodorized.

The cargo spaces, which were used for the carriage of salted fish, wet and salted hides, liquid fat, salt, cattle and other similar cargoes shall be washed, and if they were used for the carriage of wet and salted hides, they shall be disinfected. After carriage of dusty, contaminating cargoes, e. g. coal in bulk, the holds shall be hosed down.

To prevent systems (pipes) in cargo spaces of the ship from being impact by cargo, the systems should be protected by metal or wooden casings.

Hold bilge wells shall be opened up and cleaned. In case of presence of odours in draining bilges they after washing shall be dried up and sprayed with lime milk, potassium permanganate, 10 % ammoniac solution or other deodorizing substances.

Manholes of all tanks shall be examined for their leakproofness.

Inlet branches of the drainage system and sounding pipes shall be inspected and cleaned.

The ship’s derricks and cranes, when loading is to be effected by shore cranes, shall be raised and fixed so as not to impede the shore cranes operations.

When using the ship’s cargo handling gears, they shall in advance be inspected and made ready in accordance with the requirements of technical maintenance and ship’s technical documentation.

Before stowing deck cargo, it is necessary to do the following:

  1. provide and install a sufficient quantity of strong deck eyes and deck plates for fixing of lashings;
  2. protect the pipelines passing at the deck from being impact by cargo;
  3. examine the efficiency of hatch covers closures;
  4. clear drain holes and storm scuppers from dirt and examine them for their serviceability;
  5. select appropriate securing devices and lay out them at the loading points;
  6. prepare the necessary materials with an increased friction coefficient (See “Technical Characteristics of materials with an increased friction coefficient” to the present Rules) and lay out at the loading areas;
  7. mark the places on deck, which must be left free from the cargo to provide access to the fire posts, hatches, doors etc.

Fitness of the cargo spaces for the carriage of this particular kind of cargo shall be inspected by the ship’s administration and an appropriate entry shall be made about that in the ship’s log.

Distribution, stowage and securing of cargoes on board the ship

Classification of cargoes according to their model of shift

According to the mechanical model of shifting, all types of cargoes liable to shift are classified as follows:

  1. an absolutely solid body (containers, roll-trailers, heavyweight bulky cargoes and other cargo units);
  2. a continuously bound free-flowing medium (bulk cargoes and grain);
  3. a discrete structure (packages, metal rolled products, pig iron, metal scrap and so on).

Cargoes, namely:

  • vehicles (automobiles, roll-trailers, etc.),
  • railway wagons,
  • containers,
  • flats,
  • pallets,
  • portable tanks,

close to the state of an absolute solid body are exposed on board, the ship to the action of external forces, independent of the very properties of the cargo.

Depending on the securing system used, such cargoes are subdivided into:

  1. standardized cargo – a cargo which the ship is intended for and which is secured by an approved system of special devices suitable for the given kind of cargo units (containers on containerships, lighters on lighter carriers, wagons on r/w ferries etc.);
  2. semi-standardized cargo – a cargo, for which the ship is provided with a securing system capable of accommodation a limited variety of cargo transport units such as vehicles, trailers etc.

Cargoes consisting of more or less gross and homogeneous particles (grain and bulk) form a continuously bound free-flowing medium, with constant or naturally and continuously changing physical and mechanical properties. Liability of shifting in such medium depends on the strength characteristics of the cargo, which are determined by special methods.

Non-standardized cargo – a cargo, which requires individual stowage and securing arrangements.

Non-standardized cargoes are subdivided into two groups to ensure their securing:

  1. cargo units;
  2. cargo structures (structuring cargoes).

Cargo units are cargoes, stowage and securing of which are performed in an individual manner by connecting each separate cargo unit to the ship’s hull. Loading equipment or any part thereof, which belongs to the ship (ship’s tractors, fork-lifts etc.), but is not fixed to it, shall also be considered as a cargo unit.

All the rest non-standardized cargoes are considered as cargo structures (structuring cargoes), which being stowed on a ship, arrange discrete structures – bodies (stacks).

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A cargo structure is a discrete structure, comprising of separate packages, metal rolled products, pig iron, metal scrap and so on (of general or break-bulk cargo) stacked according to the given stowage pattern. The properties of cargo structures depend not only on the characteristics of individual cargo elements, but also on the order, direction and method of their stowage. One and the same cargo, stowed by using different patterns, generate different structures, which possess different properties, including resistance to shift due to external forces.

Photo of hatch covers
Upper deck hatch cover
Source: Pixabay.com

Static stability angle χ of a structure is used as a measuring criterion of ability of a stack of a structuring cargo to resist shift. It is an acute angle between the horizontal plane and the inclining bottom plane of the structure at the initial moment of its collapse in any form:

  • tipping,
  • sliding or loss of stability of the structure.

The method of determination of a static stability angle of a cargo structure (of a stack of a cargo) is given in Rules for Safe Transportation of Cargoes by Sea on the Cargo Ship“Rules and Requirements for Safe Cargo Carriage by Sea” to the present Rules.

The calculation method of shifting criterion and strength of securing devices for structurizing cargoes is given in Annex No. 5 to the present Rules.

Cargo Distribution on a ship

Any cargo aboard the ship shall be stowed so as to ensure:

  1. effective use of the cargo capacity of the spaces and the load-carrying capacity of the ship;
  2. compatibility and integrity of the cargo in the course of carriage;
  3. maintenance of the ship’s local and general strength;
  4. maintenance of the necessary trim and stability throughout the voyage;
  5. clear view of a sea surface from the conning position;
  6. non-shiftability of the cargo under the rolling and pitching;
  7. the use of shore handling equipment and unimpeded discharging and loading at intermediate ports of call.

The following cargoes shall not be carried in one and the same cargo space:

  1. soiling, dusty cargoes and cargoes which may be influenced by contamination;
  2. cargoes diffusing water for example during evaporation, and cargoes influenced by wetting;
  3. cargoes emitting odours and the ones that perceive them;
  4. cargoes evolving toxic gases and foodstuffs;
  5. cargoes containing quarantine objects and cargoes susceptible to their effect;
  6. cargoes requiring different heat- and moisture-ventilation conditions in the course of carriage.

Maintenance of the local strength specified in the ship’s documentation as the permissible deck load or tank top strength can be determined as follows:

1 by specifying the maximum permissible height of a stack of the cargo by the formula:

H = SF · q,

where:

  • H – height of the cargo stack, m,
  • q – deck load or tank top strength, t(f)/m2,
  • SF – stowage factor of the cargo, m3/t.

2 by specifying the maximum permissible number of tiers i when stacking of cargo according to the following formula:

i=tank top strength, q, t(f)/m2specific distributed cargo unit load, qc, t(f)/m2.

The view of the sea surface from the conning position shall not be obscured by more than two ship lengths, or 500 m, whichever is the less, forward of the bow to 10° on either side under all conditions of draught, trim and deck cargo.

No blind sector caused by cargo, cargo gear or other obstructions outside of the wheelhouse forward of the beam which obstructs the view of the sea surface as seen from the conning position, shall not exceed 10°. The total arc of blind sectors shall not exceed 20°. The clear sectors between blind sectors shall be at least 5°. However, in the view described in the previous paragraph, each individual blind sector shall not exceed 5°.

Distribution of the cargo on board the ship shall be determined on the basis of the stowage (cargo) plan, which is made up in two steps:

  • prior to the ship loading – a pre-stow plan (PSP),
  • and in the course of loading – an executive stowage plan (ESP).

Pre-stow plan shall be made up by an organization performing cargo loading taking into account the requirements of paragraphs 42 and 43 of the present Rules and the master should approve it prior to the loading.

When carrying homogeneous cargoes, a pre-stow plan should be made up by the ship’s administration together with a representative of the organization, performing loading.

Stowage and securing of cargo

The cargo taken aboard the ship shall be properly stowed and secured so as to prevent its shifting in the course of the sea carriage.

Stowage and securing of the cargoes shall be performed in accordance with the requirements of the ship’s Cargo Securing Manual, Cargo Information, the present Rules and taking into account the following factors:

  1. the duration of the voyage;
  2. the geographic navigation area;
  3. the expected sea condition;
  4. the dimensions, type and characteristics of the ship;
  5. the action of static and dynamic forces expected during the voyage;
  6. the type and packaging of cargo units;
  7. the intended stowage pattern;
  8. the mass and overall dimensions of cargo units;
  9. the applied calculation methods and restrictions contained therein.

Securing of standardized and semi-standardized cargoes – containers, vehicles, semi-trailers, trailers, bulky and heavyweight cargoes on specialized ships intended for the carriage of the specified categories of cargoes and equipped with regular facilities for their securing – shall be carried out in accordance with the Cargo Securing Manual and the ship’s operating documentation approved in the established order.

When necessary data is not provided in the ship’s documentation, the cargo securing shall be performed in accordance with the requirements of the Cargo Information, the present Rules and normative technical acts and also methodical documents of safe General Provisions, Rules and Requirements for Safe Carriages of Cargoessea carriage of particular cargoes, approved in the established order.

Stowage and securing of non-standardized cargoes – bulky and heavyweight cargoes – shall be performed according to individual projects, elaborated by the shippers, ship owners or, on their behalf, by competent organisations, in accordance with the requirements of the present Rules.

Shields, cages and other means should be arranged in cargo spaces of irregular configuration to ensure compactness and stability of the stack. As materials for such means, timber boards, beams, wedges, etc. may be used.

Non-shiftability of a stable stack shall be achieved by securing its surface. Securing of the stack’s surface can be effected:

1 by a tight stowage of the stable cargo throughout the entire surface of the stack in the cargo space;

2 by additional loading of another compactly stowed and reliably secured cargo, the mass of which shall be not less than the mass of the top tier of the secured stack; prior to loading, it is necessary to cover the surface of the stack with sufficient quantity of wood boards of thickness at least 15 mm; the total permissible quantity of the cargo in the stack shall be determined by the following formula:

Q = ϹB·q,

where:

  • Ϲ – length of the stack, m;
  • B – breadth of the cargo space, m;
  • q – permissible deck loading or tank top strength, t(f)/m2.

3 by one of the methods, specified in the normative technical acts and also in methodical documents of safe sea carriage of respective kinds of cargoes;

4 by other methods, recommended in the established order.

Prior to loading a cargo which is not included in the ship’s Cargo Securing Manual, the master shall familiarize himself with the Cargo Information presented by the shipper. Should there be no such information on the cargo, the master has the right to reject this cargo for the carriage.

In case the conditions for stowage and securing of the cargo, which provide its non-shiftability during the voyage (sufficient quantity of materials and securing devices etc.), are absent aboard the ship, the master has the right to reject the cargo for the carriage.

The applied securing system shall not cause any damage to the cargo. Lashings shall not come into contact with wheel tires or any other sensible parts of the cargo. Wooden or other type of dunnage shall be used when due to the securing conditions the lashings are to come in contact with sharp overhanging edges of the cargo or its parts which may be damaged by them.

Cargoes of a spherical and cylindrical shape, unpacked equipment and steel frame works, as well as cargoes in the cases, not fitted with special rings and eye plates, should be secured by lashings (belts) to be passed around.

When securing vehicles, lashings should be attached to tow hooks, apertures, loops and shackles specially intended for this purpose, as well as to the frame, chassis and other parts, fixed rigidly to the frame of the vehicle, provided the securing arrangements do not damage these parts.

When stowing cargoes of a complicated shape of their bedding area special supports or saddles should be used.

The assembly of securing system for bulky and heavyweight cargoes may include the cages, keel blocks and other arrangements designed as a part of an individual project.

Actual stowage of the cargo on board the ship shall be specified in the executive stowage plan drawn up by the organization performing loading, taking account of possible changes arising in the course of loading operations.

The Master of the ship is to ensure the compliance of stowage and securing of the cargo with the requirements of the Cargo Securing Manual and the Cargo Information.

Additional securing of the cargo by the Master’s request above the specified in the Cargo Securing Manual and/or in the Cargo Information shall be carried into effect according to the application of the ship.

The ship shall not leave the port with unsecured cargo The time of completion of the securing works and the relevant paragraph of the Cargo Securing Manual or the present Rules, in accordance with which these operations were accomplished, shall be recorded in the ship’s logbook.

Materials and devices for securing of cargoes

Classification of securing devices:

А Ship’s cargo securing devices are divided into fixed and portable (main and auxiliary) ones.

B Among the fixed securing devices are various eye rings, eye plates, shackles and sockets which are to be installed on decks, bulkheads and other frameworks of the ship.

C The main portable securing devices may be:

  1. lashings (wire rope, chain, rod and band);
  2. inserted devices (centering and tightening devices, manual and semi-automatic locks);
  3. binding devices (synthetic film, steel and synthetic bands, nets and so on).

Among the auxiliary portable securing devices are shackles, pelican hooks, clamps, clips, various tightening devices, hooks, uprights, wheel chocks, trailer horses, shoes, airbags, beams, chocks, angle bars, soft boards and antiskid materials (see “Technical Characteristics of materials with an increased friction coefficient” to the present Rules).

Securing devices on special-purpose ships (timber carriers, railway and automobile ferries, containerships, car carriers, barge carriers, ro-ro ships and ships for carriage of heavy-lifts), being a part of the ship, are specified in accordance with the character of their operation, the cargo carried and shall be of the approved type.

Requirements for securing devices:

  1. Elements of securing systems (lashings, turnbuckles and other tightening devices, quick closing convertible devices, manual twist locks and semi-automatic conlocks, angled and insered centring elements and arrangements, deck fittings, sockets, eye plates and eye rings, penguin hooks, bridge fittings, buttresses etc.) shall be in good working condition without visible signs of damage.
  2. Fixed and portable securing devices shall meet the requirements of normative-technical documents, approved in the established order, and have current documents, containing data on the permissible Safe Working Load (SWL) and/or breaking (extreme) load (BL).
  3. Elements of securing systems shall provide a definite Safety Factor (See Table A.6.1 of Annex No. 6 to the present Rules).
  4. Elements of securing systems shall be marked by their manufacturer. The marking, shall contain values of the Safe Working Load (SWL) and/or breaking (extreme) load (BL).
  5. Handling and maintenance of the ship’s multiple-use securing devices shall comply with the requirements of normative-technical documentation, approved in the established order and may be defined concretely in the Cargo Securing Manual.
  6. Wire rope lashings, at the positions of connection with turnbuckles, shackles and other elements, shall have eye splices with fixed thimbles preferably. Fixing of thimbles may be carried into effect by wire rope clamps. The quantity of claps is determined according to the diameter of the rope, but in any case it should not be less than three.
  7. Before leaving the port, tightening elements should be tightened for not more than a half of their working stroke to ensure the ability of tightening during the voyage. At the same time, the force of tightening shall not be excessive.

Material Consumption for securing of cargoes:

  1. The average material consumption per 1 t of cargo can be determined according to the data contained in Table A.6.2, Annex No. 6 to the present Rules depending on the kind of general cargo. Implementation of materials with an increased friction coefficient, including soft kinds of wood (fir and pine), considerably allows to reduce the expenses for securing.
  2. Determination of the type and quantity of materials used to secure heavyweight and bulky cargoes, whose distribution and stowage on ships are executed according to individual projects, are implemented by the designers of the project individually in each case and approved inside the project.
  3. Materials used for cargo securing shall be in compliance with the requirements of normative-technical documentation, approved in the established order as well as with the present Rules and quarantine requirements.
  4. Dunnage used for separation of cargo consignments should be intact, uninfected by biological bodies and chemical substances, dry, clean and should not give off alien odours if they can harm the cargo.
  5. Paints used for separation shall be harmless for the cargo and the ship’s personnel.
  6. Marks made with special pencils and crayons should be clear and undeletable in the course of cargo operations and transportation.

Ensuring the safety of the ship and integrity of cargoes during the voyage

During the voyage, it Is necessary to maintain regular control of the ship’s stability by measuring the roll period. A sharp increase of the roll period indicates that significant reduction of the ship’s stability has occurred.

During the voyage, it is necessary to maintain regular receiving of weather and sea condition reports and forecasts in order to avoid the ship getting into a seaway zone, where the level of heaving exceeds the assumed value when calculating the strength of securing of the cargoes.

When it is not feasible to avoid such heaving, all measures should be taken to ensure tightness of the ship’s hull and, when necessary, an inspection of securing of the cargoes should be executed with the relevant safety measures taken. Entering an enclosed cargo space shall be allowed only after a test for the absence of toxic and deleterious factors, posing hazard to human life and health, has been conducted.

When inspecting the state of the cargoes, attention shall be paid to:

  1. shifting of the cargoes;
  2. slackening of securing arrangements;
  3. loosening of configurations of the packaging and their deformation;
  4. possibility of dynamic contacts of cargo units with each other and with structures of the ship’s hull;
  5. redistribution of loads arising as a result of disengagement from functioning of securing components and dunnage, and which exert negative affect on the strength of the ship’s structures, cargo and its securing;
  6. damage of the cargo;
  7. condensation on the cargo and the ship’s structures;
  8. other conditions and circumstances, which could adversely affect the cargo
    condition and quality.

When any of aforementioned conditions and circumstances are revealed, measures on their elimination should be taken and when necessary additional securing of the cargo (retightening, wedging, installation of additional dunnage and so on) should be effected. The results of the inspection shall be recorded in the ship’s logbook.

Measures to be taken against loss of buoyancy, ship’s stability and shifting of cargoes:

  1. at storm conditions, all entrances and other closures, through which water can leak inside the ship’s hull or superstructure, deckhouse etc., shall be closed;
  2. it is necessary to keep sidescuttle in good working condition and they shall be reliably secured at storm conditions;
  3. scupper holes should be cleared and be in working condition;
  4. the number of partly filled tanks on board should be minimum;
  5. the ballasting shall not be started, especially in heavy seas, without having calculated the ship’s stability and influence on it of the ballasting;
  6. tanks which contain free surfaces, except the service tanks, should be, where possible, pressed before starting the ballasting operations;
  7. only one tank or one pair of tanks, should be ballasted simultaneously, if ballasting of a single tank can cause a visible heel;
  8. the ballasting operations shall be commenced with the tank, whose free surface will cause the least correction to the metacentric height (as a rule, they are end tanks);
  9. rectangular amidships tanks are as a rule the last to be filled;
  10. ballasting should be effected as fast as possible;
  11. ballasting of any tank shall not be stopped until the tank is fulfilled; the ballasting of the next tank shall be started only after the previous tank is fulfilled;
  12. other appropriate measures.

When heel appears, the dynamic loads upon the ship should be reduced immediately. For this purpose, it is necessary:

  1. to reduce speed;
  2. to put the ship’s bow up sea; however, in case of poor stability this measure should be taken with great care bearing in mind that a turn, even in still water, can cause an additional heel of the ship;
  3. in case a constant heel has appeared it is necessary to make sure, by control pumping out of draining bilges and bottom tanks, that the heel is caused by cargo shifting;
  4. as far as possible, taking the relevant safety precautions (see paragraph 65 of the present Rules), to achieve increase of the ship’s stability by means of ballasting and to proceed out of the storm area by the shortest safe course;
  5. complete eliminating of the heel by ballasting is allowed only after the ship has escaped the storm area.

Main requirements for safety techniques to be applied when securing cargoes

When securing cargoes, one should be guided by Safety Rules for the maritime fleet ships and Regulations for Personnel Protection approved in the established order.

Manholes and hatch covers shall be fixed by locking devices. Prior to entering the hold, it is necessary to make sure that the locking devices are fixed reliably.

Entering or leaving the hold shall be performed in one by one manner and with the permission of the signalman.

It is forbidden to enter or leave the hold:

  1. when there is poor lighting;
  2. having any objects in hands;
  3. when cargoes or handling devices are hoisted or lowered.

in the course of handling it is necessary to control stability of the stowed cargo. It is forbidden to leave the cargo in an unstable condition.

Lifting of personnel up to the height of deck cargo should be carried out with the help of a stepladder erected against the cargo at an angle of 60°-75° towards the horizon and equipped with holders and antiskid shoes.

When lashing or unlashing cargoes during night time simultaneously with regular lighting additional lighting by lustre and floodlight should be provided.

Personnel carrying out lashing or unlashing the cargoes should wear gloves, helmets, buttoned up clothes and laced up antiskid footwear.

Lashing and unlashing of containers of large capacity shall be carried out only by persons, who have been trained in safe methods of conducting of these works according to a special programme.

When carrying out works on securing of cargoes at a height, e. g. of a stack of containers, personnel shall be provided with safety belts fixed upon the ropes, going along the ship, providing movement of the personnel and preventing them from falling down. Works on securing of containers of the second and next tiers shall be performed from a special suspended cradle equipped with guardrails.

Technical Characteristics of materials with an increased friction coefficient

Brizol (bituminous rubber) of types BR-S and BR-P according to Specifications TU 38.1051819-88, is baseless material, manufactured by forge rolling and further calendering of a mixture, consisting of oil bitumen, crushed rubber (of old automobile tires), asbestos and plasticizer, Brizol is supplied in rolls 425 – 1 000 mm wide. Length of a sheet in a roll is 10 – 50 m.

Ruberoid is carton according to GOST 3135, impregnated with soft oil bitumen (roofing) according to GOST 9548 with further application of high-melting bitumen with filler to both sides of the sheet and coarse-grained grit to one side of the sheet. Ruberoid is supplied in rolls of 1 000 – 1 050 mm wide. Ruberoid is supplied in rolls 10 – 15 m long. Ruberoid does not evolve toxic substances when heated up to 70 °C.

Izol according to GOST 10296 is a baseless bio-resistant, water- and vapour proofing material, made of from rubber-bitumen agent, plasticizer, filler, antiseptic and polymeric additives. It is supplied in the form of roils of sheets of 2 mm thick, in rolls of 800 or 1 000 mm wide and 10 or 15 m long.

Fibreglass ruberoid according to GOST 15870 is a roofing and waterproofing material on a fibreglass base made by means of double-sided application of binding bitumen agent on fibreglass canvas. It is supplied in the form of sheet of 2,5 mm thick, 960 or 1 000 mm wide, 10 m2 area, folded in rolls. It is manufactured with coarse-grained (S-RK), fine-grained (S-RM) or scaly (S-RCH) grit on the face side and fine (powdered) grit on the underside of the material. Fibreglass ruberoid with scaly grit (S-RCH) shall not be applied for cargo securing purposes.

Timber of predominantly soft of little value sorts, in the form of boards, beams, wedges and plywood.

Other kinds of special materials with an increased friction coefficient or gluing effect.

When calculating shifting of cargoes the values of friction coefficients singled out in table 1 in bold, shall be applied, if other values are not specified in the Cargo Information.

Table 1
Friction pairStatic friction coefficient, fArctg (f)
cast iron – steel0,3218°
cast iron – timber0,7236°
cast iron – brizol (bituminous rubber), ruberoid0,8139°
steel – steel0,15/0,18/0,2112°
steel – timber0,3/0,4/0,5-0,6 (0,5)27°
steel – rubber0,5/0,6/0,7 (0,6)31°
steel – ruberoid0,735°
timber – timber0,45/0,65 (0,55)29°
rubber – timber0,6/0,8 (0,7)35°
sacking (jute) – sacking0,6232°
sacking – steel0,4525°
sacking – timber0,527°
reinforced concrete – timber0,5529°
paper – paper0,422°
paper – steel0,3519°
paper – timber0,422°
Footnotes
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