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Harbors: Loading Procedures

As soon as the vessel is docked, the terminal chief should review the loading plans with the master of the vessel. They should agree on any changes. The procedures for loading are described below:

 

LOADING PROCEDURES

 

As soon as the vessel is docked, the terminal chief should review the loading plans with the master of the vessel. They should agree on any changes. The procedures for loading are described below:

 

Grounding

 

After the vessel is moored and all safety precautions are taken, and before cargo hoses are connected, the vessel must be grounded to the dock. To ground a vessel, personnel must--

 

        Inspect the grounding system to verify continuity and testing according to applicable standards.

        Make sure the grounding switch is open.

 

        Make sure the grounding clamp on the grounding cable is attached to a bare metal surface on the hull of the vessel. It may be necessary to sand a spot on the hull to make a good connection.

 

        Check the grounding system to see that there are no loose connections.

 

        Close the grounding switch.

 

Deballasting

 

Often, quantities of ballast water, needed to maintain proper vessel trim, are delivered to a terminal. The ballast must be removed from the vessel before it is loaded. It is against regulations to dump water containing petroleum products overboard. The best way to deballast at the terminal is to pump the ballast through a separate pipeline and oil and water separator to shore ballast tanks. Sometimes tank barges are used as ballast tanks. The terminal may not have a separate pipeline to handle ballast or the vessel may not have a stripping system. In these cases, cargo lines and pumps may be used if ballast water is clean and if lines and pumps are drained well after they have been used for ballast. Deballasting procedures must be followed carefully because product contamination may result from improper handling of ballast water. When pumping ballast ashore, personnel must--

 

        Determine the amount of ballast to be pumped ashore, and make sure the shore tanks have enough ullage to hold it.

 

        Connect one end of the ballast hose to the ballast pipeline connection on the dock.

 

        Connect the other end of the ballast hose to the stripping connection on deck.

 

        Open the valves aboard the vessel to empty the desired tanks.

 

        Open the correct shore valves to permit pumping to the ballast tank.

 

        Start the stripping pump.

 

        Watch the pressure gage to make sure the proper valves are open. If the pressure is higher than normal, the line may be blocked.

 

        Permit no ballast water and product to be transferred at the same time unless there is an emergency. Even though the water and product are separated by valves, product may become contaminated.

 

        Continue pumping until all possible ballast water is removed from the vessel. Because of heavy deck cargo, it may be necessary to leave ballast in some tanks to stabilize the vessel during loading. Personnel should avoid doing this when possible.

 

        After all ballast is removed, stop the pump and close the shore valves so that ballast will not drain back into the vessel lines.

 

        Open valves in cargo lines, except sea suctions, to observe any line drainage into cargo tanks. They must make sure that cargo lines are drained completely.

 

        Make sure that each tank is free of ballast and suitable to receive product. Personnel must clean tanks that are unsuitable to receive product. They should refer to Chapter 12 for guidelines on how to prepare cargo tanks to receive petroleum products.

 

Inspecting Vessel

 

Before product is loaded aboard a vessel, each tank compartment and all pumping and cargo lines must be inspected by the shore petroleum inspector. To certify that they are suitable to receive product, the inspector must-

 

        Plan the order in which products should be delivered and choose which tanks will be filled first.

 

        Inspect the hull of the vessel to the extent possible to see that it is not damaged and that there are no leaks.

 

        Examine the pipelines, pumps, and deck manifold of the vessel for leaks or damage. Make sure that pumps and piping systems are free of product or water.

 

        Open all of the valves in the cargo lines, except the sea suction valves which must be sealed. From outside the tank, watch for any line drainage into the cargo tanks. The shore petroleum inspector must make sure that the cargo lines are completely drained.

 

        Inspect the interior of each compartment visually to make sure the tank is suitable to receive product. Use an explosion-proof flashlight. Look for scale, rust, holdover product, residue, water, mud, or anything else that might contaminate product to be loaded. Chapter 12 gives procedures and precautions on entering tanks.

 

        Check the ship's log to determine the last product to be loaded. Chapter 12 contains information on how to prepare the tank to receive the next product.

 

        Make sure that all fire and safety precautions have been taken.

 

Connecting Cargo Hose

 

The terminal furnishes hoses for loading and unloading vessels that are operated by non-DOD personnel. These hoses are usually connected and disconnected by shore operators. However, if the master of the vessel desires, the hoses may be connected or disconnected by vessel personnel at the risk of the vessel. When vessels have military operators, the vessel personnel normally connect and disconnect hoses on the vessel and the shore personnel connect and disconnect hoses on the shore. Military tank ships, fuel barges, and other vessels usually carry hoses; however shore hoses should be used when possible to save time. Most tankers have American standard 4-, 6-, or 8-inch flanges for hose attachment. They will cause no problem. Some tankers may have foreign made flanges or flanges with irregular spacing between the holes that need adapters or C-clamps. Older tankers may use the same spacing between holes for both 4- and 6-inch flanges. The terminal should have a set of straight and reducing adapter spools on hand to cover all normal requirements. It should have several sets of bolts, preferably of alloy steel. In all cases, at least four bolts will be used per coupling unless a camlock flange or C-clamp is used. If C-clamps are used, their strength must be verified by test or calculation. To prevent sliding or twisting, at least two bolts must be inserted through the vessel flange and hose flange when C-clamps are used. Although it is hazardous to do so, C-clamps may be knocked off in an emergency. Quick-acting clamping devices should be used instead of C-clamps, when possible. To connect a cargo hose, personnel must--

 

        Make sure the vessel is grounded to the dock manifold before any hoses are connected.

 

        Make sure the hose is suitable for handling product. They check the hoses for

 

        contamination, cracks, holes, worn or frayed places, or other damage.

 

        Place drip pans under connections on deck and on dock to catch spills.

 

        Attach the hose to the hose support. Personnel raise the shore end of the hose in position to couple it to the dock manifold. They attach the hose flange securely to the manifold connection using all of the bolts.

 

They place the other end of the hose where it can be picked up easily by the ship's hoist.

 

        Attach the hose to the ship's hoist and raise it in position to connect it to the deck manifold. They align the holes of the hose flange and the deck manifold flange and bolt them together securely. The hose should be suspended above the deck during transfer.

 

Connecting Loading Arms

 

At some tanker loading facilities, marine loading arms (Figure 4-10) are used instead of cargo hose. The arms are operated by cables and hydraulics. Most marine loading arms have hydraulic connections instead of flange connections. To connect loading arms, use the following procedures:

 

        Make sure the vessel is grounded to the dock manifold before the loading arm is connected.

 

        Make sure the loading arm is suitable for handling the product. Check for damage or wear.

        Place drip pans under connections on the deck to catch spills.

 

        Lower the loading arm to make the connection to the deck manifold.

 

        Attach the loading arm connection to the deck manifold, making sure the seal is tight.

 


Figure 4-10. Marine loading arm

 

Heating Cargoes

 

When tanks have heater coils, viscous products in the tanks should be heated to prescribed temperatures before transfer operations begin. Prescribed temperatures must not be exceeded. Very high temperatures deteriorate products and can cause vapor lock in pumps. Navy special burner fuel oil and heavy lubricating oils should be heated to above 100?F, but not over 120?F.

 

Pumping Product

 

Shore pumps usually are used to load vessels. If possible, the pier lines should be filled with product and samples should be tested before the vessel arrives. All valves to be used on the shore lines should be opened, except those used to prevent cross transfer and the valve at the pier hose connection. Special procedures should be followed when jet fuels or kerosene is pumped. Procedures to pump product are as follows:

 

        Open the proper valves aboard the vessel so that product will flow to the correct tank from the dock manifold.

        Open the proper shore valves to permit flow to the vessel.

 

        Start the pumps, and operate them at a slow speed. Closely watch the pumping pressure shown on the pressure gage. The gage is usually in the line near the dock manifold. If too much pressure builds up quickly, it means a valve is closed in the line. In this case, shut down the pumps at once. Do not start pumping again until the problem is corrected.

 

        Watch all hose and line connections for leaks. If there are leaks, stop the pumps immediately. Fix the leaks before starting again.

 

        Watch the receiving lines and valves for leaks during the operation. A line walker should inspect the lines for leaks once every hour.

        Carefully watch for changes in the tide and for slack or pull in the hose. Sudden movement of the vessel may cause damage to the hose and loss of product.

 

        In case of fire on the vessel or dock or near the shore lines or tank farm area, stop the transfer operations at once and close all the valves. If the tank farm is next to the port, disconnect the cargo hose and move the vessel a safe distance from shore.

 

        When an electrical storm is within a 3-mile radius of the transfer operation, stop transfer operations and close the valves on the vessel and dock. Coordinate on the weather before transfer operations are started. Maintain coordination during transfer operations if an electrical storm is probable. If there is no immediate hazard, the hose may be left connected. If there is an immediate hazard, the hose should be disconnected and drained and the main block valve on shore should be closed.

 

        Avoid sudden increases in flow that might cause excessive surge pressure. When the product level is about 3 feet above the inlet, start the desired pumping rate. If there is still turbulence at this level, continue loading at the maximum allowable rate until it is time to top off the tanks.

 

        Top off the tanks when they are about 90 percent full. While topping off the tanks, reduce the loading rate to avoid spills or overflow.

 

        Watch the vessel's draft during loading so that it will not become overloaded.

 

        Shut down the pumps and close all of the valves when all the yanks are filled and the vessel has proper trim.

 

Performing Follow-Up Procedures

 

Certain follow-up procedures must be performed after a vessel is loaded. These procedures are as follows:

 

        Allow the suspended water and sediment to settle. Gage the contents of each tank compartment, and find the average temperature of the product at 60?F in each tank.

 

        Take an all-levels sample of product from each tank compartment that contains the same product. Run a type C test on each sample according to  FM 10-67-2. Make a multiple tank composite sample to be sent to the laboratory for testing. Use MIL-HDBK-200 as a guide.

 

        Gage the product in the shore tanks. Find the average temperature of the product. Quantities are volume corrected according to  DA Pamphlet  710-2-2. Compare the quantities delivered from the shore tanks with the quantities received in the vessel's tanks. Shore gages must be used to get the exact amount delivered. Note any difference between the amount delivered and the amount received. Report the differences to the proper authority.

 

        Close and securely bolt all compartment hatches when the desired amount of product is loaded and is certified as on specification. Make sure that all ullage sounding holes are covered securely, and seal all areas required by regulation. Record all seal numbers on  DD Form 250.

 

        Pump ballast water into the proper tanks if the vessel needs ballast for proper trim for the voyage. The tanks must be clean before ballast is received. Only clean ballast should be pumped into the tanks.

 

        Make sure that all line valves are closed. Disconnect the cargo hose, and drain any remaining product from the hose. Catch any spills in drip pans placed beneath the hose to drain into the water or on the dock. If spills occur, wipe them up immediately. Cover the hose ends with blind flanges and gaskets. Store the hose in a shelter or hose rack.

 

Refueling and Bunkering Tankers

Tankers may be refueled at the port terminal. The same procedures are used to issue fuel as those used to load fuel in the tanker. All bunkering operations should be recorded on  DD Form 250-1. Samples must be taken to detect contamination. All safety precautions must be followed. After refueling, disconnect the refueling hose, open the grounding switch, and disconnect the bonding cable from the ship, in that order.


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