Step 2 of 5•4 minutes read
Tank Stripping Using FRAMO Pumps
Stripping on traditional ships required an eductor or positive displacement pump and cargo pumps to remove all of the liquid from the tanks. Using the FRAMO system, a stripping line is built into the pump to conduct the operation without additional pumps.
Once the pump loses suction, the pump is switched off, and the discharge valve is throttled to drain the cargo line. The cargo purging line is connected to the inert gas flow to speed up this process by pressurising the line.
Once the line is purged, the FRAMO pump is restarted. This is then used to prevent back pressure from forming in the system so that the tank can be fully stripped. You may open the stripping line valve and regulate the air from the inert gas system. It is then important to carefully monitor the level within the tank to ensure that all of the cargo is stripped from the well before shutting down.
Some vessels' cargo systems are also fitted with an optional vacuum drain. This is an integrated eductor run using the inert gas system connected directly to the FRAMO pump. After stripping, the vacuum line can be opened, and all remaining residues in the well are removed using this line. This is very useful for final stripping before tank entry or even to speed up the stripping process for fast cargo turnout.
Shutting Down
Shutting down the operation must be completed correctly to ensure that all cargo is properly stripped from the tank. First, you must close the stripping valve, then the purge line, and stop the cargo pump.
Note: This stripping process may well need to be repeated if there is some liquid left in the tank.