AMET University, Chennai.

B.Sc. Nautical Science Semester- IV

SHIP OPERATION TECHNOLOGY- III (Cargo Work)

Unit-2 Deck Cargo, Cargo stowage Plan and Unitizationof Cargo

ObjectivesL: At the end of this lesson the students should have proper understanding of:

1) Basic problems associated with the carriage of cargoes on deck, like safety of personnel and the cargo, security of cargo and larger concern of safety of ship during the voyage;

2) The elements which a Cargo officer must factor in , like, ship’s stability on arrival/departure each port, conforming to draught restriction, if any, ship’s structural strength (Bending moments/ Shear forces), Loadports/Disports rotation etc., when preparing/planning a Cargo stowage Plan:

3) Concept of Unitization of Cargoes and it’s impact on loading/discharging in ports and care of cargoes during the voyage.

Introduction: During the last 5 decades there has been tremendous development in packaging, handling and transportation of Goods, both solid and liquids. Containerization has virtually changed the concept of the high value finished goodsas to how they are to be packed, handled and transported across the seas. Gone are the days when Conventional Liner ships used to carry variety of cargoes (from Coal-tar in drums, Vegetable oil in Deep tanks, Grain and minerals in bulk, fruits, Poultry and Meats in refrigerated chambers, Machinery and finished goods in cargo hold and vehicles/project cargoes on deck) serving variety of trade between selected ports at each end of the voyage. Today’s specialized ships load and discharge at great speed and carry specially packed cargoes across the oceans in much shorter time.

Specialization and Unitization has been the result of considerable research and innovations, dictated by the ever changing social and economic environment. Today’s ships are not only designed and constructed to meet specific requirements of Trade but also are provided with Handling Gear, eqripment and appliances as well as skilled seafarer. Specialized and matching infrastructure and equipment has also been provided in ports and terminals around the world. To properly exploit the benefits of specialization and unitization even intermodal transport systems and infrastructure on Land (Rail, Road and even inland waterways) had to be developed. Today Shipping has become highly capital intensive industry requiring highly skilled operators both on ships and ashore.

Nowadays very close co-ordination and cooperation is required between the ship’s staff and the shore terminal/Port staff to discuss and execute the loading/discharging plansand to avoid any delay/ detention/damage to ship, since both the ship and the Terminal are highly capital intensive assets.

Unit-2

Deck Cargo Requirements:

1. Load density should not be exceeded

2. The ship should have adequate GM to maintain stability;

3. No damage should occur to the water tight integrity of the ship to avoid ingress of water when the vessel is at sea;

4. Should not interfere with opening and closing arrangements of doors, sounding pipes, air vents, etc;

5. Safe access should be marked around the ship and nothing must obstruct the safe access around the vessel. So as to provide safe access between accommodation, gangway and places of work on board;

6. Should not stow the cargo to height where it interferes with the navigation of the vessel;

7. The stow should be compact and solid as practicable.

Deck Cargo Safety Code – Application

This code applies to the loading and carriage of any cargo loaded on any exposed deck, other than timber deck cargo on every ship.

Stability

Deck cargo to be so loaded as to ensure sufficient positive stability throughout the loading period and the voyage. Under deck cargo not to be loaded or discharged without ensuing that the ship is having adequate positive GM.

If in spite of all the precautions ship develops a list – it shall be immediately corrected.

If angle of loll develops – all cargo operations to be stopped and actions taken to upright the ship and to make GM positive, if necessary by discharging deck cargo, ballasting of bottom tanks, loading weight under deck etc.

Stability for the voyage should take into account the worst sea/weather conditions with due regard to free surface effect of liquids in the ship’s tanks.

Ships of less than 100 metres LOA shall be provided with the stability information and direction as recommended by IMO to enable master to calculate the minimum and maximum GM and a substantial range and area associated with the righting lever curve.

In all ships master should be guided by the ships stability documents in regard to the calculation of minimum and maximum GM of substantial range and area associated with the righting lever curve.

Deck Cargo Safety CodeTransport Publication TP 2072 E

1. Application

1.1 This code applies to the loading and carriage of any cargo loaded on any exposed deck, other than timber dock cargo, on every ship.

2. Stability

2.1 The Master should ensure that cargo shall not be loaded on the deck of a ship, unless that ship has an initial margin of stability sufficient to permit the maintenance of a safe margin of positive stability throughout the loading operation and voyage.

2.2 The Master should ensure that no cargo shall be loaded into, or discharged from, the lower decks while deck cargo is on board except when the Master has satisfied himself that the ship will retain safe positive stability throughout the cargo handling operation.

2.3 If at any time during cargo operations an abnormal list develops such list shall be corrected forthwith.

2.4 If a ship develops an angle of loll the Master shall cease all cargo operations forthwith until corrective measures have been determined and carried out (including, if necessary, the discharge of deck cargo, the loading of lower compartments or the filling of double bottom tanks) as may be required to return the ship to a normal safe condition of positive stability without loll.

2.5 The Master should determine the ship’s stability for the worst voyage condition taking into account the free surface effect of liquids carried on board the vessel.

2.6 Ships under 100 metres, (328 feet), in length should be provided with the stability information and direction as recommended by Resolution A.167 (ES-IV) of the Inter-Governmental Maritime Consultative Organization (IMCO) at Annex I. to enable the Master to calculate the minimum and maximum metacentric heights and a substantial range and area associated with the righting lever curve.

2.7 In all ships the Master should be guided by the ship’s stability documents in regard to the calculation of minimum and maximum metacentric heights and of substantial range and area associated with the righting lever curve.

3. Securing of Deck Cargo

3.1 The Master should ensure that cargo stowed on any exposed deck of a ship shall be stowed or secured so as to prevent its movement. When securing is necessary it should be carried out prior to the ship being exposed to any conditions likely to produce movement or shift of the deck cargo.

3.2 Vessels which are not normally fitted with securing arrangements, generally found in special purpose container vessels, should give particular attention to the stowage and securing of containers when carried on deck. Masters should be guided by the recommendations of the Inter-Governmental Maritime Consultative Organization in Annex II.

4.Vessels fitted with side, bow or stern loading doors

4.1 The Master should ensure that cargo shall not be loaded on, or discharged from, any exposed deck of a ship fitted with side, bow or stern loading doors unless such doors are secured ready for sea, except as provided in Section 4.2.

4.2 Cargo may be loaded on, or discharged from, an exposed deck of a ship with side, bow or stern loading doors open when special safety precautions are observed. Such precautions should include routine procedures carried out by trained personnel, ensuring an upright condition, safe trim and a minimum freeboard below the door sill consistent with the designed safety criteria of that vessel. Due consideration shall be made of the prevailing sea, weather or other special conditions.

5. Safe Access

5.1 The Master should ensure that the deck cargo is stowed and secured in such a manner as to provide clear all round visibility from the navigation bridge and to give safe and satisfactory gangway access to all accommodation, working and machinery spaces, life-saving and firefighting equipment and other equipment and areas to which access is necessary for the safe working of the ship at sea and in port. He has the responsibility under the Safe Working Practices Regulations to provide guard rails, lines or other protection, around open hatchways and open spaces in the deck stow.

6. Stress on Deck

6.1 The stow of the deck cargo should be so arranged that the stress exerted by the cargo does not exceed the designed maximum permissible stress on the deck areas or hatches upon which it is stowed.

7. Inspection

7.1 In accordance with the provisions of the Canada Shipping Act a Port Warden shall, upon request of the Master or Agent, board a ship which is about to load, or has on board, a deck cargo, to survey the ship’s stability condition and the arrangements made for securing the deck cargo add providing safe gangway access and guard rails.

7.2 On the request of a port warden conducting a survey in accordance with Section 7. 1, he shall be supplied with a calculation or other satisfactory declaration of proof of the ship’s stability, signed by the Master.

Securing Deck Cargo:

Cargo stowed on any exposed deck shall be stowed and or secured so as to prevent movement. When securing is necessary it should be carried out prior to the ship is exposed to conditions likely to produce movement or shift of the deck cargo (bad weather).

Basics of Cargo Securing:

- Ensure tight and compact stow throughout the hold.

- Heavy units are loaded below and secured so as to prevent slipping, tipping and damaging other cargoes or ship structure.

Use fixed securing points. Securing points provided for inland transportation may not be suitable for seagoing conditions.

Keep lashings as short as practicable.

If multiple lashings are provided ensure that all lashings are maintained at equal tension.

Avoid mixing of devices with different strengths and elasticity.

All lashings should have tensioning gears and must be capable of being checked and tightened on passage.

Lashings must be sufficient to prevent the load from moving when the ship rolls through 30 degrees with 13 second duration.

Cargo to be secured down which will prevent movement’

Basics of Safe slings:

- The load must be as secure when lifted as it was on the ground.

- Load to be contained within the sling – bags in nets.

- Fixed lifting points/lugs, if available.

Basics of safe slinging:

· Load to be secured when lifted.

· Load to be within the slings (bags inside net).

· Use fixed lifting points if available.

· Rope or wire slings wrapped completely around the load – no loads resting in loose bights of line.

· Specialised devices to be used as per the instruction manual.

· Sling to be adequately attached to the lifting appliance.

· Load must not distort while lifting.

· Load must not damage or break the sling.

· The sling must not damage the load.

· Lifting parts should act as near to the vertical as possible.

Standard Safety Precautions during cargo work:

· Sufficient lighting to be provided during cargo operations.

· Guards must be erected around all openings.

· Do not walk under load which is off the ground.

· Do not walk on the hatch coaming.

· Opening and closing of the hatch covers to be supervised by responsible officer.

· Use check /steady wires if there is a possibility of hatch covers running due to list or trim.

· Portable ladders to be secured properly before put in use.

· OOW should ensure that the stevedores are NOT engaged in unsafe acts.

· Proper access and illumination to the holds to be provided.

· Gangway access properly rigged and well illuminated.

· Container ships stevedores attending to twist locks and other lashing gears.

Lashing gear Turn buckles

Cargo Stowage Plan:

· Cargo to be so stowed that it can be loaded and discharged fast.

· Cargoes are not under carried or over carried.

· Cargoes are not under stowed or over stowed.

· Cargo to be labelled or colour coded for effective identification.

· Cargo for a specified port should be distributed with other holds so that faster discharge or loading can be affected (more hooks can be used). But ensure the economic viability of such distribution.

· Cargo to be stowed that it does not move or shift during sea passage.

· Prevent tainting and contamination by proper segregation and separation . Cargo plan to be prepared by the C/O and given to the stevedore company and port authorities and the OOW.

Vessel aground

Preloading Plan:

The C/O will make the plan taking various factors into consideration:

· Quantity of cargo

· Segregation and/or Separation

· Securing

· Load density (permissible load on decks).

OOW to ensure that the cargo is loaded as per the stowage plan and any deviation to be brought to the notice of the C/O. Many changes can/will occur and C/O will amend the plan accordingly (Flexibility allowed). OOW should hand over the status of cargo work accurately to the next OOW.

Stability

Ensure vessel’s stability is maintained at all times.

The cargo to be loaded and discharged in such a sequence that the minimum positive GM is maintained at all times.

Bending moments and Shearing forces should be within permissible limits.

Load density should not be exceeded on any deck in the cargo spaces.

Ballast Operation

When loading, the ballast will be pumped out and vice versa to maintain the stability and stresses within limits.

Do not press up the tanks, specially D.B. tanks, with cargo inside the holds, to avoid possible leakages.

Features of a cargo plan

1. The location of each item with a brief description.

2. The weight of major units and the total weight of stow of each parcel.

3. The load port and discharge port of each stow; standardised colouring if available to be provided.

4. The major units to be marked clearly and legibly.

5. Bill of lading numbers to be indicated in each consignment.

6. Details of type and position of separations.

7. Remarks of stowage to aid the stevedores.

8. Over-stow of cargo, if any, to be marked to aid discharge of the correct items and enable timely shifting of the cargo on top.

Racking stress

Unitisation of Cargo

Pre-slung loads

Cargo packed and loaded with the lifting gear in place. Help in faster movement of cargo. E.g. pipes, timber machinery parts. This results in quick turn around and substantial savings at discharge or load port where the stevedore costs are high.

Palletised load

Unit loads are packed onto general purpose 4 way entry pallets and secured. Pallet shall be less than 1.32x1.092x1.372m size and its gross weight should not exceed 1.5 T. The cargo may overhang the pallet no more than 50 mm on each end and 38 mm each side. Palletised load is expected to occupy 2 Cubic Meter of space. The cargo and pallet secured together. Common method is steel straps. Dragging of palletised cargo is to be avoided.

Generally Fork Lifts are used to stow palletised cargo. Palletised cargo generally do not require any dunnage.

Pallets lowered into the hatch square and then the fork lift lifts the pallet and proceeds to stow.

Sometimes if the fork lift cannot stow on top of the other due to insufficient head room then 2 pallets are lifted together and stowed.

Filler cargo can be used to fill up void spaces. If forklifts are to be used on top of palletised cargo then 2 layers of dunnage (normally strong Plywood sheets are laid), one transverse and other longitudinal to be laid out over it.

Containerisation

Faster turn-round of ships in port with minimum labour utilization.

Container being sealed is pilfer proof.

Easier further forwarding to destination

Multimodal form of transport is facilitated with proper infrastructure over land (Rail, Road etc.)

Up to 30Mt of cargo can be moved in one lift.

Types of containers

1. General

2. Reefer

3. Tank containers

4. Open Top

5. Flat racks

6. Fantainer

7. Half height containers

8. Bulk containers

9. High cube containers

Ro Ro

Ships where Cargo transport units are driven into the holds and driven off the holds. This is to enable faster load and discharge of cargo. Not normally engaged in deep sea navigation.

Lash vessels (Lighters aboard ship)

Single deck ship equipped with Gantry Crane (SWL 450 MT) which travels longitudinally and can manoeuvre transversely also. Ship has wide stern opening (above the propeller and Rudder) to facilitate lifting and lowering of barges.

Barges are loaded onto the ships at anchorage and then discharged into anchorages. No berthing facility was required and were being used in ports of mostly undeveloped and developing countries during 1970s and 1980s when ports used to be badly congested.

Lighters are thin skinned boxes with water tight hatch covers. They carry around 375 MT of cargo. Some lighters are equipped for easy ventilation and provide for smoke detection and fire extinguishing.

SEABEE

Seabees are members of the United States Navy construction battalions.

Sea Barges are very similar to the Lash vessels barges. Barges are brought to the stern elevator and moved internally within the ship by the Transporter (conveyor) system. Ships can carry up to 38 sea barges. The elevator capacity is 2032MT.

The Seabees have a history of building bases, bulldozing and paving thousands of miles of roadway and airstrips, and accomplishing a myriad of other construction projects in a wide variety of military theatres dating back to World War II.

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