Page 413 - Pipeline Pigging Technology

Pipeline Pigging Technology

Fig.6. Flow rate vs time.

2. The water tank was filled and pressure was applied by opening the
transfer valve (control valves were closed, so only the air tank and
water tanks were pressurized).
3. The pig or pig train was installed in the launcher and the piping was
filled with water.
4. The appropriate control valve or valves were gradually opened,
causing the piping to reach equilibrium with the tank pressure (no
appreciable flow occurs since the exhaust valve is closed).
5. The recorders were started and synchronized.
6. Flow was initiated, launching the pig or pig train by opening the 4-
in exhaust valve.

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