Flushing of piping

[srisua]

Dear Seniors,

Kindly suggest me the requirements of cardboard blasting/air blowing piping
we have installed piping, working pressure is 54kg/cm2, temperature is ambient. We are going to do hydrostatic test with a pressure of 81 kg/cm2. Customer asked us flushing procedure. I said as we are going to do hydrotest with high pressure no flushing is required as debris, dust will go off along with water when releasing pressure after hydrotest. As customer is stringent about flushing, I have given an air blowing procedure i.e, closing one end with cardboard and applying pressure with compressor air from opposite end, after certain pressure cardboard will blast and debris will go along with air shock wave.

Now my customer question is at what pressure cardboard or film will blast. I explained him that in this case pressure is not important, we have to apply continuous pressure till film blast. If debris is not cleared properly, test shall be repeated until it clears.

Now kindly suggest me whether I am right or not

Regards

 

[LittleInch]

srisua,

See this -

http://www.oceanteam.eu/images/Serv...ipes_Gas_Discharge_BackPuffing_Ocean_Team.pdf

"Cardboard" won't get you a high enough pressure and might not break in a rupture fashion.

The thing you have to remember about this is that it works very well for the piping close to the bursting disc, but then gradually works less and less well as you get ot the other end, to the point where dust doesn't move.

Flushing is normally a high flow rate flush with continuous air or liquid flow to properly remove debris, dust etc until there is no more.

Looks to me like you're trying to do this on the cheap....

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[LittleInch]

I also meant to say, naturally make sure no one is in the way and make sure everyone knows it is going on.

The first time it happened to me I thought something had blown up and dived for cover as they hadn't told me it was happening. It is a hell of a bang....

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[srisua]

Thank you little inch. you are 100% correct. I am trying to do this on the cheap only. your suggestions are well taken and follow

Regards
Srisua