Hydrotest 2

[Simdro]

Dear All,

I’m following the supply for Equipment which is designed in accordance with ASME VIII Div.1 but the design pressure is equal to atmospheric pressure.
As scheduled on relevant QCP the Vessel shall be subjected to Hydrotest full water filling it in Vertical position.
Some days before the mentioned test the Vendor has asked me to perform a 100% LP on main welds only for the following reasons:
- The Hydrotest in Vertical position cannot be carried out considering that the Vessel weight full water filled is too high.
- The Hydrotest in Horizontal position cannot be carried out considering that on the center top head of Vessel there is an inspection opening (see attached file - two halves - DN1000) no leak proof.

Any suggestions on the matter would be greatly appreciated.
Thanks in advance.

 

[eyec]

did your QCP call out any NDE on the root welds?

Steven C
Senior Member
ThirdPartyInspections.com

 

[Simdro]

QCP calls out a Visual Weld Examination and a Radiograpic examination only.

 

[eyec]

when were xrays performed root or finished weld?

Steven C
Senior Member
ThirdPartyInspections.com

 

[LOUDOG]

You could weld on a temporary cover for the hydrotest.

 

[Simdro]

Thanks for both your helps.

Anyway the Vessel is designed with Xray Spot (joint efficiency=0.85) so that the X-Ray are performed spot on main welds (longitudinal and circunferential) includung cross-welds.
The top dished head in fully radiographed and LP tsted.

EyeC
Maybe I think that the X-rays were performed on finished welds.
I'll make you confirmation asap.
Thank you again.

 

[eyec]

what percent of welds were xrayed

Steven C
Senior Member
ThirdPartyInspections.com

 

[Simdro]

Please find enclosed the relevant X-rays map.

 

[vesselfab]

Well...assuming it is designed and built per code and not stamped.

those covers on top head will not hold much/in any pressure.

The only way to test this, if structure and vessel will withstand the weight, is to fill it up after it is erected.

Another way is to weld on test covers at those openings on heads and do a pnuematic test with pressure at vertical height of vessel times 0.433 and hope all your welds are good.

Your client may accept full mt/pt or ut in lieu of testing.

 

[eyec]

were there any reject/re-weld for those welds xrayed?

if no, then i would not be concerned with the welds or lp of them.

is this a hopper for a feeder for light weight materials - looks familiar?

i think the concern of the vendor is valid and would look at welding a blind on the inspection opening and do a pneumatic test @ LOW PRESSURE

Steven C
Senior Member
ThirdPartyInspections.com