Definition - What does Pig Launcher mean?
A Pig Launcher is a designed and fabricated tool used to launch Pig's inside Crude Oil, Petroleum Products or Gas Pipelines. Pig refers to pipeline intervention gadgets that are used to perform multiple maintenance operations such as cleaning and inspection inside the pipelines. Pig Launchers are generally funneled shaped Y sections that can be aligned with the main pipeline through which an operator can launch a Pig inside a mainline. These launchers can be pressurized or depressurized depending on the requirement.
Petropedia explains Pig Launcher
A precise procedure for launching a Pig varies depending on the Pigging system used by the Pipeline Operating Organization. However, following steps are used broadly:
- Close the isolation and kicker valves.
- If it’s crude oil or products pipeline, air should be allowed to displace the liquid through drain and vent valves in the launcher to create atmospheric pressure. If it’s gas pipeline, only the vent valve should be opened.
- Maintain 0 psi pressure within Pig Launcher and load a Pig with its nose in contact with the reducer.
- After sealing and lubricating the complete system, make sure trap doors are closed and secured.
- The kicker valve is slowly opened so that the trap gets filled with the liquid or gas.
- The next step is to close the vent valve once filling is complete in order to equalize the pressure across the isolation valve. This pressurizes the Pig inside the launcher.
- The gradually kicker valve is completely opened, thereby increasing the flow of crude oil, petroleum products or gas inside the launcher. This inserts tremendous pressure on the backside of the Pig which pushes it into the mainline and carries it all along, thereby performing all the pigging operations.
- At the end of the pipeline a similar funneled Y shaped section is attached which is called a Pig Receiver that catches this Pig and the entire internal residue of a pipeline.