Ball valve passing after pigging

[jibran42]

Dear friends,
we have a 24" full bore ball valve installed at the inlet of scraper,pigging was done and the pigg was received at our scraper.
after this the ball valve started passing. can some body help me in this regard.
is it design fault or the pig fault or the particles came along while pigging

[myaseenm]

Dear friends,
we have a 24" full bore ball valve installed at the inlet of scraper,pigging was done and the pigg was received at our scraper.
after this the ball valve started passing. can some body help me in this regard.
is it design fault or the pig fault or the particles came along while pigging

Jibran,

Leaking of ball valve at pig receiver site may be caused by several incidents,

1) ball valve seat gets misaligned during its opening or closing sequence. (possible cause may be no maintenance of ball valve like flushing and opening and closing, etc)
2) Pig fault! you have to look at nose than. (examine the receiver barrel concavity with the mainline and the reducer section and clearance of pig plus the distance and pig body length)
3) Metallic debris can hurt but there presence is necessary when you receive the scrapper pig.

In my opinion the tool (scrapper Pig/Brush or Magnetic one) have minimum probability to damage the valve specially full bore ball valve, the leaking must be caused by over turning or partial closure or seat misalignment.

Hope that will help you to discover the answer...