Hydrotest-Sightglass 2

[vesselrajj]

Hi guys,
Is it advisable to do hydrotest of a newly constructed pressure vessel with sightglass on. My hesitation is, the purchase requirement of sightglass states only design temperature and pressure of a vessel which is less than the hydrotest pressure.There is some pressure value stated on the glass which is also less than actual test pressure. Since this is a HSE issue, I dont want to take any risk. please advise..Thanks

 

[gr2vessels]

Please contact the supplier of the sight glass and ask him about the maximum pressure it can withstand in any condition, including the hydrotest.
Cheers,
gr2vessels

 

[vesselrajj]

gr2vessels,
I sent a query mail to my supplier earlier.I m awaiting for his reply. Anyway whats code requirement over this.Whether Section VIII insisting to use sightglass during hydro or not?. what is the normal practice?

 

[SNORGY]

I would close the gauge valves or cock valves to the sight glass and open the drain to atmosphere, if possible. If the valves pass, you pick up the leak without pressurizing the sight glass. You might need to remove the sight glass ultimately if that happens.

 

[gr2vessels]

The code is not providing specific requirements for the sight glass, in other words does not require sight glass. As above, is not common practive to use sight glass for hydrotest and in fact I cannot see any use, when there are other proven methods to ensure complete venting of the vessel during the filling with water.
Best regards,
gr2vessels

 

[chicopee]

I would isolate the sightglass. Look at it from that standpoint being that the sightglass is not the object under test, just the vessel,tube sheets, fitting connections,nozzles, manway rings, and any other pressure parts are being tested.

 

[SNORGY]

I think g2vessels and chicopee capture another useful point. Namely, while you might be able to make effective use of the sight glass during filling prior to pressurization for the test, it is otherwise not a requirement.