Station · Pipelines
Pig Traps
The pressure rated traps at each end of a pipeline segment where pigs and inspection tools are loaded and taken out.
What it does
The barrel is isolated from the line with full port valves; flow pushes the pig out of the launcher and the receiver catches it at the far end, usually at a valve or pump station. A pressure warning device alerts the operator to any pressure left in the trap before the closure is opened.
Basics
| Location | Valve or pump stations, at segment ends |
| Carries | Cleaning pigs and in line inspection tools |
| Safety | Pressure warning device on the closure |
| See also | Flow Assurance site |
Common failures
- Opening a trap that still holds pressure
Troubleshooting
- Symptom
- Pig does not arrive at the receiver
- Likely cause
- Tight bend, unbarred tee or a valve not fully open
- What to check
- Check valve positions and track the pig