Safety Pig laucher and receiver for natural gas pipline cleaning

Description:

Launcher:

• Pipeline operator should make sure that the isolation valve and kicker valve are closed.
• If the system is a liquid system then the drain valve and vent valve should then be opened to allow air to displace the liquid; if the system is a gas system then the vent should be opened so that the launcher reaches atmospheric pressure.
• After the PIG launcher is completely drained to 0 psi, with the vent and drain valves still open, the trap door should then be opened.
• The PIG should then be loaded with its nose in contact with the reducer.
• Closure seals and other sealing surfaces should be cleaned and lubricated as needed and then the trap door should be closed and secured.
• The drain valve is then closed and the trap is slowly filled by gradually opening the kicker valve.
• Once filling is complete the vent valve is closed so that the pressure will equalize across the isolation valve.
• The isolation valve is then opened and the PIG is ready for launching.
• Next the main valve is gradually closed, increasing the flow through the kicker and behind the PIG until finally the PIG leaves trap altogether and enters the pipeline itself.
• After the PIG leaves the launcher the mainline valve is fully opened and the isolation valve and kicker valve are closed.

Receiver:

• The receiver should be pressurized.
• The bypass valve should be fully opened.
• The isolation valve should be fully opened and the mainline valve partially closed.
• Once the PIG arrives the isolation and bypass valves should be closed.
• The drain valve and vent valve are then opened.
• Once the trap is fully depressurized to 0 psi the trap can be opened and the PIG removed.
• The closure seal and other sealing surfaces should be cleaned and lubricated as needed and the trap door should then be re-shut and secured.
• The receiver should then be repressurized and returned to its original condition.