NDT Requirement

[ssreekylm]

HI ....
What type of NDT that you prefer for the butt welded cap with the vent connection.Normally i had seen the cap as threaded and we are preferring DPT for the seal weld.But here we have the doubt that 100% RT /UT is required?

 

[racookpe1978]

What Code applies to this system?
What fluid pressure, temperature, and service?

If a threaded fitting were used before (to the vent ? Or to the relief valve inlet?) and a seal weld, why was the seal weld used? (Was it on the pressurized side of the vent ?)

Why do you think a 100& UT and RT is required?

 

[ssreekylm]

Code which prefer is B31.3 and Exactly i dont have the Temp and pressure value.Just confirmed that high pressure service and material is ASTM A 403 Gr.WP304/304L.And with respect to the design, Even it is normal service also ,vent cap are seal welded.Technically i dnt hav much idea regarding the requirement of seal weld or butt weld in vent closure. Hope some one can explain the same and As per B 31.3,

345.2.3 Special Provisions for Testing

(c) Closure Welds. The final weld connecting piping
systems or components which have been successfully
tested in accordance with para. 345 need not be leak
tested provided the weld is examined in-process in
accordance with para. 344.7 and passes with 100% radiographic
examination in accordance with para. 344.5 or
100% ultrasonic examination in accordance with
para. 344.6.

 

[DekDee]

ssreekylm,
A butt welded cap onto a vent line is no different to any other joint in the system.
If you are required to do 100% RT/UT then this will most definitely include your joint."
Not sure why you have posted an excerpt from the code detailing closure welds - your situation is not a closure weld,
Cheers,
DD

 

[ssreekylm]

DekDee,
I agreed with you that normally it is not a closure weld.But,due to the reason of this joint design is groove and It will be welded after hydro test its comes under the closure weld category or not?

 

[DekDee]

Not