MarFlex

Cargo pump cofferdam cannot be purged (no air, inert gas, or liquid from check pipe)

Check for insufficient purging medium supply. Verify valves, hose connections, and the purging medium relief valve (set at approximately 3 bar) are open. Inspect the exhaust trap and deck piping for blockages and clear them if possible. If the blockage persists, disconnect the check pipe from the pump unit and carefully purge to determine if the blockage is in the check pipe or the pump/pipe stack cofferdam. Use steam or solvent to dissolve the blockage, and dismantling of the pump may be necessary. Perform a leak test after assembly.

Cargo leakage into pump cofferdam is observed

Perform a leak test on the pump cofferdam system at approximately 3 bar. Spray with soapy water to locate the leakage. If no leakage is detected by the leak test, the cargo leakage is likely due to a worn cargo seal. Replace the cargo seal set and inspect the ceramic sleeve for damage or wear. Check flange connections for loose bolts or pitting corrosion in seal faces; repair corrosion and renew damaged seal elements during assembly. If the issue persists, contact a service station.

Hydraulic oil leakage into pump cofferdam is observed

Drain the pump return side before dismantling. Disconnect the pump head/unit from the pipe stack/casing. Pressurize the pump unit return side to approximately 4 bar and check for leakage to the cofferdam side. Perform a leak test on the pump pipe stack/casing at a maximum of 7 bar on the cofferdam side and check for leakage to the return side. Replace the shaft seal (recondition if feasible) and check the sealing surface for damage, repairing if necessary. Renew damaged seal elements during assembly. If the issue persists, contact a service station.

Cofferdam is blocked

Operating the cargo pump with a blocked cofferdam is not recommended. For advice on how to proceed, depending on the type of cargo, contact a service station.

Leakage rate of cargo into cofferdam is 2 litres/day or higher for critical cargoes

Purge the pump a couple of times daily and perform service (leak test and repair) at the first available opportunity. Intensify purging if the leakage rate exceeds acceptable limits. If this is not sufficient to control the leakage, consider discharging the tank using a portable pump, depending on the cargo type.

Leakage rate of hydraulic oil into cofferdam is increasing above acceptable levels

Purge the pump a couple of times daily and inspect it at the first available opportunity to find the reason for the leakage. Intensify purging if the leakage rate is still increasing. If the leakage is not brought under control, close the hydraulic service valve. Depending on the nature of the cargo, consider using the portable pump to discharge the cargo.