PWHT requirement for LPG

[paddy1385]

Hi,

We are having LGP service for one of our project, is PWHT applicable here?
Thickness of pipe is 5.49 mm so by code its not applicable.

 

[metengr]

Which code????

 

[BigInch]

With that thickness, not necessary. Pipe grade?

 

[paddy1385]

I am using LTCS pipe ASTM A333 Gr.6.
My worry is about LPG .. whether it needs to have PWHT to avoid brittle fracture.

 

[DekDee]

If it is B31.3 your P1 material does not require PWHT for that thickness (unless required by project specifications)
Cheers,
DD

 

[BigInch]

A333 is the best choice for low temperature LPG.
Sounds good to go.

 

[AdibaaQudoos]

PWHT is mandatory for all special services, i.e lethal, cryogenic and Unfired steam boilers, whatever the thickness is, see UW-2 (a)
As per ASME section VIII division 1, Table UCS-56.1, General notes (b)
LPG is not a special service.

1- PWHT is mandatory for welded joints over nominal thickness 38 mm.
2-PWHT is mandatory over nominal thickness 32 mm through 38 mm nominal thickness unless provided preheat for minimum temperature of 95 degree Celsius.

In your case, PWHT is not required as per code, but if recommended by purchaser, then its mandatory to perform for holding time of minimum 15 minutes at 595 degree Celsius temperature.
Cheers

Adiba Qudoos