SECTION 1 - LOADING AND STOWAGE

Planning
It is important not to allow loading to begin before a stowage plan is agreed. Stevedores may be in a hurry to start. They might have to wait, but by approving the stowage plan before the beginning of loading, the Master can avoid worse delays later and prevent damage to cargo, his ship and the lives of those on board.

If a Surveyor is attending, he should assist and advise the Master in checking the stowage plan.

Loading wet cargo
Wet cargo in a ship's holds increases humidity in the air and vapour pressure. The presence of wet cargo in the holds will therefore lead to moisture damage to cargo that was sound and dry on shipment.

Rain during loading
Category A packed or wrapped products must not be left uncovered on the quay or loaded during rain.

Category B non-packed or non-wrapped products will often be stored on the open quay and loaded during light rain. This is usually acceptable provided they are not going into the same hold as dry products.

A suitable descriptive clause (for example "Wet before Shipment") should be prepared for insertion on Mate's Receipts and Bills of Lading for any wet cargo. Watch out for coils that appear to be dry on the outside but which drip water from the windings when lifted.

Hatch covers and all other deck openings should be closed in good time to stop rain getting to cargo in the holds.

A careful note of the timing of any rain and of the opening and closing of hatch covers should be made so that the Master can check that the timings in the Statement of Facts presented to him for signature match the timings in the ship's log.

Incompatible cargoes
Care should be taken not to load incompatible cargoes (such as chemicals, fertilisers, sulphur-bearing materials and, in many instances, hygroscopic cargoes) in the same compartment as steel cargo.

Strength of tank tops
Bundles of reinforcing bars and bundles of small scantling materials can be stowed in tween decks. Unpalletised steel coils must never be stowed in tween decks. The ideal stowage position for steel products is in the bottom of the vessel, on the tank tops.

Steel is a high density, deadweight cargo. The danger of tank top overload must be considered and avoided. The Master should calculate the permissible tonnage and this figure should never be exceeded.

The permissible tonnage is calculated as follows:
Area of tank top (M2) x Tonnes per M2 tank top strength limitation.

The tank top strength limitation figure is supplied by the shipbuilder and approved by the Classification Society. The figure usually remains unchanged throughout a ship's life. The strength of the scantlings of the component parts of a ship reduces over the years. The older the ship, the more caution should be exercised in calculating the permissible tonnage - a greater safety margin should be left for older vessels.

If the permissible tonnage is exceeded, the tank top plating may be deformed. In order to spread the pressure evenly over the tank top and thereby reduce structural deformation, dunnage should be adequately spread, this to avoid spot overloading.  

Stowage and lashing of different types of products

Steel coils

No. 1 Hot rolled steel coil provided with steel channels to prevent edge damage

 

No. 2 Cold rolled steel coil 

In coils of up to 15 tons, the tank top should be dunnaged with two double lines of 6"x1" (15cm x 2.5cm) dunnage wood boards. For coils of over 15 tons, three lines of such dunnage should be used. In order to achieve tight stowage and prevent movement, wooden chocks must be inserted on top of the lines of dunnage in the lower tier.

For handling steel coils, chains and wire rope slings should never be used. The safest lifting gear is a round steel pole through the centre of the coil, or a "C" hook.

The correct method of stowing hot and cold rolled steel coils (except for palletised coils) is usually with their centre cores fore and aft. If they are stowed any other way, they are more likely to shift. Steel coils must never be stowed in tween decks, except for palletised coils in special circumstances.

If it can be avoided, coils should not be stowed in a single tier, unless they are overstowed with other cargo. If there are only enough coils for a single tier and nothing can be placed on top, an ideal stowage would be to stow the coils in two tiers at the after end of the compartment. If single tier stowage cannot be avoided, each athwartship tier must be secured with a locking coil.

As a general guide, the following weight/height ratio should be applied -

10 ton coils: 3 high
15 ton coils: 2 high
15+ ton coils: 1 high

The age of the vessel and strength of the tank tops should be considered, and a lower ratio applied if appropriate to a particular vessel.  

Begin stowage against the end bulkhead in the centre and the wings, with the gap between the wing and centre stowage closing to leave a space for the insertion of locking coils. The stow should be arranged so that the second tier locking coils do not protrude down into the cantlines of the lower tier by more than one-third of the diameter of the locking coil.
Ideally, the athwartships lines of cargo should extend out to the extremities of the cargo hold. If stevedores are not equipped with the necessary gear to do this in the upper tiers, a mobile crane can be used to put the outer coils in place.

Drawings "A" and "B" (see next page) and photographs "3" and "4" show the recommended method of securing with strapping bands. Passing bands through the cores of adjacent coils prevents fore and aft movement. Crossing bands over the top of coils prevent up and down movements, when the ship is pitching. This method also stops individual coils from turning in stow.
When you have a single tier, the locking coil should be secured as shown in drawing "C".

Drawing A

Drawing B

No. 3 Steel coils recommended securing

No. 4 Steel coils recommended securing

Drawing C

(1) The wire is led through the centre of coil "B" from front to rear side.
(2) The end is then passed upwards at the rear side and through the centre of coil "A".
(3) It passes back downwards on the front side through the centre of coil "B".
(4) The wire then passes upwards and diagonally over the top of coil "A" to the front where it is passed downwards.
(5) It passes through the centre of coil "C".
(6) It then emerges at the rear side. Passing up and through the centre of coil "A";
(7) It continues back down again at the front side through the centre of coil "C".
(8) At the rear side the wire is taken upwards diagonally across the top of coil "A" to be connected to the opposite end of the wire where it is joined with a span screw.

Drawings:
Courtesy of LLP Limited from the publication Steel - Carriage by Sea - 2nd edition by Arthur Sparks MNI.

Steel strapping bands should always be tightened with pneumatic tools never by hand operated tools. The ends of the securing bands should always be joined with two crimp seals.

Metal strapping bands should ideally be used to secure steel coils, for the following reasons:
- Each coil can be efficiently secured through its core to the two coils beneath - costly perhaps, but the safest method.
- Using a pneumatic tightening tool, bands are tensioned up to 2,000 kgs.
- Bands are applied singly, making it easier to handle them and pass them through awkward gaps.
- Tension is uniform throughout the stow. (Do not use securing timbers, which defeat this purpose.)

If wire rope is to be used to secure steel coils, the following precautions should be taken:-
- All bulldog grips should be properly fitted and adequately tightened.
- Three bulldog grips should be fitted either side of the spanscrew.
- The turnbuckles should be extended to the maximum of thread before application of the wires in order to ensure that after tightening not more than 1/3 of the thread is used. This will allow for further tightening.

Bands/wires should be passed as in Drawings A and B.

Steel slabs

No. 5 Steel slabs awaiting shipment 

Mild steel slabs are relatively thin rectangular blocks of steel, weighing up to 20 tons per piece. A popular size can be 6500mm x 1200mm x 250mm with a specific gravity of 7.85; such a slab weighs 15.3 tons. Steel slabs are the basic material from which most steel products are manufactured. Slabs are usually stored in the open - unusually: for steel products, wetness and rust staining is of no consequence.

The traditional stowage method has been to load slabs with their longitudinal axis athwartships, right out to the ship's sides over and above the sloping plating of the hopper tanks. Dunnage was inserted between each tier, to allow re-slinging for discharge. Building out to the ship's sides produced a staggered stow, more stable than a uniform pile. With a part load, the best stowage position was thought to be at either end of the hold, close to the bulkhead.

Such cargoes are now usually carried in bulk carriers, of between 20,000 and 40,000 tons deadweight for full cargoes. In a 30,000 ton ship, the tank tops of the main holds would be about 16m wide. In such ships, the traditional stowage method would produce an unacceptable amount of broken stowage, or loss of space, in some areas.

This can be avoided by combining traditional athwartships stowage with fore and aft stowage. Complete fore and aft stowage is acceptable in some cases, provided the stow is built out over the hopper tanks. It is particularly important with steel slabs always to remember one of the basic principles of good stowage: to interlock the individual blocks, like building a brick wall. Non-interlocking stacks should be avoided if at all possible. All gaps in the uppermost horizontal tier should be secured with suitable sized timber.

As stevedores are able to load heavier and heavier weights, methods of stowage have been devised in which the stevedores simply lower large single loads and stack them in the hatchway square, leaving large gaps at the sides and sometimes at the ends of the holds. These methods of stowage are not recommended and should be avoided for the reasons explained above. It may sometimes be acceptable, but only in vessels with box-shaped cargo compartments.

The danger of tank top overload should always be borne in mind and avoided by reference to the permissible tonnage and by use of suitable dunnaging, when possible.  

Hot and cold rolled steel in packages and bundles

No. 6 Bundles of hot rolled steel sheeting

No. 7 Hot rolled steel in bundles

No. 8 Cold rolled steel sheeting in packages

No. 9 Cold rolled steel sheeting in packages 

Cold rolled steel sheets are wrapped and referred to as packages. Hot rolled steel sheets are unwrapped, in bundles. Packages usually measure about 1m x 2m x 15cm, weighing about 2,000 kgs. Bundles are of more variable thickness and therefore variable weight.

These products should be stowed right out to the ship's sides with their longitudinal axis athwartships. No gaps should be left between the edge of the stow and the ship's sides/hopper tanks. Packages/bundles usually have bearers, either longitudinally or transversely. If the bearers are transverse and the units are placed athwartships, as they should be, two lines of 6"x1" single dunnage boards should be inserted to tie the stow together and keep it level.

If the tank top is not entirely covered, the "brow of the stow" i.e. the gap between the end of the stow and the bulkhead(s), or adjacently stowed cargo, must be secured, to prevent movement in a fore and aft direction. Dunnage can be laid on the tank top as appropriate.

Before commencement of loading, 16mm wire cables should be laid fore and aft, about 3m apart. When loading is completed, a 6"x1" board lattice fence is fitted to the face of the stow. The securing wires on the tank top are then brought up over the stow to be attached with a span screw to the opposite ends, and then tightened. Gaps between the top layer packages/bundles are secured by wedging and/or tomming.  

Single plates

No. 10 Single hot rolled steel plates awaiting shipment 

Single steel plates are usually quite long and, although heavy, they lack rigidity because of their length. If they are not handled and stowed carefully, they may become kinked.

Single plates are ideally stowed in the same way as steel slabs. Suitable lengths of dunnage should be inserted between each tier of plates or tier of lifts of plates. The dunnage must be kept in line vertically, close enough together to stop the plates bending, where there are gaps between dunnage.

Plate-type hooks and clamps are used to secure the wire legs to the plates and are usually attached to a spreader. 

Structural steel

No. 11 Structurals: hot rolled steel beams or joists stored on the open quay 

Structural steel products are usually shipped in bulk carriers. Beams and channels commonly sustain crushing and deformation damage. This can be avoided by placing the products carefully and correctly, and by proper dunnaging.

Before commencement of loading, 3"x3" dunnage in cross section should be laid in athwartships lines across the tank top plating. The space between the lines of dunnage fore and aft, should be about 3 m. This pattern of dunnage should be separated between every tier, in order to bind the stow together and to allow re-slinging for discharge. The dunnage should be kept in line vertically. Every effort should be made to have beams with their webs placed vertically in stow.

These products should ideally be stowed in a fore and aft direction. If they are to be stowed athwartships, lifts should be placed fore and aft in the wings against the hopper tanks or ship's sides. The ends of the products should butt up against these lifts. The ends of athwartships steel must never be allowed to come into direct contact with the ship's sides.

The stow is secured in the upper tier or tiers. With large beams or channels, wood-wedges and timber dividers between the gaps is usually adequate. Reinforcing bars do not normally need to be secured. With bundled goods, some securing may be necessary in the upper tier. Timber or wedges should be driven between the bundles in the upper tier, particularly with tightly banded, small dimensional angles, etc.

These goods are usually handled by means of chains and wire slings. Care must be taken not to overload slings. This is especially important when handling beams, which may become bent or dented at the flanges.

Sheet pilings
Sheet pilings should be stowed in the same way as structural steel, except that they are stacked on top of each other, to form unsecured bundles. Care should be taken to ensure that stacks are not excessive, or the top piles may crack.

Special care is needed in slinging. Braided slings are recommended, to avoid damage to the keying devices on the sides.  

Pipes

No. 12 Pipes correctly bundled and strapped 

Small diameter pipes are stowed in the same way as small scantling structural material. Large single pipes are always stowed fore and aft. Pipes must never be crossed - each pipe sits in the cantlines of the two pipes underneath. Athwartships lines of single flat dunnage are first laid upon the tank top and the first tier of pipes is laid side by side in a fore and aft direction.

If the pipes are not a perfect fit on the tank top or in the lower tiers, wooden stools should be built in the wings of the areas of the slope of the hopper tank sides.

Some coated pipes require special care in handling. The shipper may provide special lengths of packing, to stop these pipes chafing against each other. In such cases, and where there are unusual fabrications and finishes, the shipper should provide special guidance.

When loading is completed, the top tier of pipes must be secured. With some kinds of pipes, driving securing timber through gaps and the use of wires may not be advisable. Side chocking may be required in the area of the wings and the sides of the stow.

The Master should always check stacking limits before the beginning of loading.

Short single pipes may be loaded with wires hooked into the end of the pipes, attached to a spreader. Bevel ended pipes are loaded by wire slings, but the flat-plate type hooks on the ends must be copper lined or hard plastic coated. With special coated pipes, the wire sling may have to be covered in canvas.  

Wire rods

Wrapped

No. 13 High tensile wire rods fully wrapped

Unwrapped

No. 14 Hot rolled wire rods: no wrappers, (unprotected) stored in the open

Coils of wire rods usually consist of wire with a diameter of between 5mm and 9mm. Bundles usually consist of three or four separate coils. Coils may be shipped singly or in unitised bundles. Units normally weigh about 1.2-1.5mt each. They are secured with flat metal strapping bands. These should be applied after the bundles have been compressed. Bundles secured by strapping bands are very rigid - in this state they are in the best condition for stowage in a ship's hold. Slack bundles which are not tightly pressed and secured in this way can suffer during handling, securing bands can converge and through pressure in the stow, wires can splay out and become damaged. In addition, serious tangling of windings can result.

Two lines of single flat dunnage should be laid on the tank top athwartships under each line of coils. Wire rods are not a high density cargo. Unlike most steel cargoes, they take up a lot of hold space. Coils or bundles are stowed on the tank top in lines across the hold, with the centre core pointing fore and aft. These products are stowed in the same way as hot/cold rolled steel, but with rods it is not necessary to arrange locking coils. Sometimes these cargoes are simply dumped in the hold. This should not be allowed. These products need to be stowed carefully and properly, like any other. The wire should not be allowed to rest against the ship's structure, or chafing damage can occur.

If it is intended to load a different, low density cargo on top of wire rods, remember that wire rods settle and sink considerably after loading. Stowage and lashing of other cargo on top should be planned with this fact in mind.

Soft copper wire rod is shipped in an unpacked condition and if great care is not taken, it may become chafed, kinked or scored, causing substantial cargo claims.

Stowage certificates
If a Surveyor has been appointed to follow the loading operations, he should produce a stowage certificate showing:
- Stowage per cargo hold.
- Dunnaging of cargo.
- Measures taken to secure the cargo.
- Any interventions by the Surveyor which have led to changes in the stowage/lashing arrangements.
- Details of any differences of opinion, with whom, on what subject, with what result.

Before departure, the Master should be provided with copies of a stowage plan, hatch lists, etc. He may be asked to sign a document confirming that stowage and securing has been carried out to his satisfaction. The Master should obviously not sign this document if he disagrees with it or has any doubts.

The golden rules of stowage
Proper and efficient stowage is essential to avoid shifting, chafing and crushing damage. The guidelines for particular cargoes, as set out above, should be followed, and the following five Golden Rules should always be observed.

Golden Rule 1:
Before loading begins, check that there is adequate suction on all bilge lines. The date of the test and results should be appropriately entered in the deck log book.

Golden Rule 2:
A reasonable inspection of the cargo holds must be carried out before loading commences. The date and name of the vessel's officer who inspected the holds must be entered in the deck log book.

Golden Rule 3:
Never go to sea with the top horizontal tier of a steel cargo not fully completed. If the tier cannot be completed it should not be loaded, as securing with wires to the ship's sides and tomming with timber cannot be considered as proper precautions against shifting with this type of cargo and in this particular situation. In certain circumstances this rule may not apply to steel coil cargoes.

Golden Rule 4:
Steel products should never be permitted to rest against the ship's structure in stow: dunnage should always be used to prevent this occurring.

Golden Rule 5:
Underdeck steel cargoes should not be secured to component parts of the vessel's structure, with the exception of wire rod cargoes in certain circumstances (for example, half hatch stowage).

 

SECTION 2 - ON THE VOYAGE

Supervision of loading, stowage and discharging
Surveyors may be available to help and advise the Master but it is the Master's responsibility properly and carefully to load, stow, carry, care for and discharge the cargo. He may at some stage be obliged to prove that he fulfilled this responsibility and in doing so took all measures humanly possible to protect the cargo while it was in his custody.

The maintenance of the vessel
In negotiating cargo claims, damage caused by lack of maintenance of the vessel often leaves the carrier with no defence. As a result of this he may have to pay the claim in full or otherwise settle on very poor terms even when other factors have played an important part in causing the damage. Proper maintenance is, of course, essential.

Watertightness
Steel cargoes are almost always high density deadweight cargoes. Vessels carrying these cargoes have a high range of stability and work heavily in a seaway, imposing concentrated stresses in various areas of the hull structure; especially in the area of the hatchways. If the hatches are to remain watertight it is essential that all component parts of the steel hatch closing appliances are maintained to a high standard. This also applies to all other main deck openings.

Ventilation
Most moisture damage and subsequent rust damage to steel cargoes is caused by cargo sweat and/or ship sweat. Steel loaded in a cooler climate going to or through a relatively warmer climate will, if ventilated, probably suffer from cargo sweat (that is, condensation of moisture directly onto the actual cargo). On the other hand, when a ship travels from a warm area to a relatively cooler area, the steel cargo is vulnerable to being affected by ship sweat (that is, condensation forming on the component parts of the ship's structure within the cargo holds dropping back onto the cargo) if proper ventilation does not take place.

Steel cargoes should therefore not be ventilated when passing from a cool climate to a relatively warm climate. Cargo should be given full ventilation when temperatures are falling. It will therefore be necessary to maintain temperature records from the commencement of loading up to completion of discharge. These records will enable the carrier to prove that all necessary measures were taken to care for the cargo during the course of the voyage. In the negotiation of cargo claims it is of great importance that correctly kept records are available which will accurately and acceptably correspond with the manner in which the ventilation was used.

When it is decided that the cargo should not be ventilated every effort must be made to seal off the cargo hold from the outside atmosphere. The aim should be to make the cargo hold as air-tight as possible. If cargo hold dew point temperatures are closely following outside atmospheric dew point temperatures, then the exercise is not working: hold sealing arrangements should be re-checked.

If there is any leakage of hatches, however slight, or the ingress or presence of free moisture in the cargo hold (for example, due to a flood back along bilge lines, the ingress of rain during loading, the presence of other cargo loaded in a wet condition, or the cargo holds not being dry when loading commences), there will be an appreciable increase in the relative humidity of the ambient air surrounding the cargo, resulting in copious cargo sweat and ship sweat, possibly accompanied by serious cargo damage.

Some Owners/operators equip their ships with either permanent or portable cargo hold dehumidification units which have proved to give satisfactory results.