WPS / PQR with impact test

[Syahar1975]

Dear experts,

Our contract agreement is WPS / PQR for vertical with SMAW must be impact tested even by the code we are exempted for this impact test.

Vertical seam on our shell plate would be :

a. P1 Gr 2 welded to P 1 Gr 2. Shell plate thickness range from 6 to 37 mm.

b. P1 Gr.1 welded to P1 Gr. 1. Shell plate thickness range from 6 to 8 mm.

All these vertical will be welded by SMAW process.

My plan is : make PQR with one test coupon with P1 material and thickness is 19 mm. This coupon will be tensile stressed, banding stressed and impact tested.

The problem is our client welding engineer insist to provide 3 PQR coupons with various thicknesses. He said due to impact test we need to provide 3 coupons with different thicknesses. He can't explain to me which standard address this requirement.

I can't find that requirement in API 650 nor ASME Section IX.

Your comments is highly appreciated.

Syah

 

[denlow60]

Hello Syahar1975,
This is what API 650 say about it .

9-2 API STANDARD 650
9.2.2.5 Impact tests shall show minimum values for acceptance in accordance with 4.2.8.3 and the following:
a. For PI, Group 1, materials-20 J (15 ft-Ibt), average of three specimens.
b. For PI, Group 2, materials-27 J (20 ft-Ibt) , average of three specimens.
c. For PI, Group 3, materials-34 J (25 ft-lbt) , average of three specimens.

 

[Syahar1975]

Good evening Denlow60,

Thanks for the response.

You are right that in this paragraph API 650 states the impact test base on P no and Group 2.

But there is no requirement based on thicknesses.

So in my case, I only need 2 PQRs to be impact tested since I have P1 Gr 1 and Gr. 2.

For P1 Gr. 2 I will make 19 mm plate as PQR test coupon.

For P1 Gr. 1 I will make 6 mm plate as PQR test coupon.

 

[CWEng]

See ASME Section IX QW-403.6 for impact testing thicknesses for base metal. Welding a plate >19mm will qualify from 16mm to your maximum thickness. Welding a 6mm plate will give you 6-12mm. If you don't have anything in-between 12mm and 19mm, then those two tests will suffice. If you do, then a third plate thickness is needed, but if you test both Heat affected zoned, it can be a 2nd,thicker plate welded to your 6mm plate.

 

[Syahar1975]

Dear CWEng,

Thanks for your explanation.

Welding a plate > 19 mm will qualify from 16 mm to maximum thickness. This maximum thickness meaning un-limited ?

Yes we do have plate thickness between 12 mm to 19 mm.

So my client is right I need to prepare more than 2 PQR coupons.

Syah

 

[Syahar1975]

Dear CWEng,

I have gone thru QW-403.6 :

QW-403.6 The minimum base metal thickness qualified
is the thickness of the test coupon T or 5/8 in.
(16 mm), whichever is less. However, where T is less than
1/4 in. (6 mm), the minimum thickness qualified is 1/2T.
This variable does not apply when a WPS is qualified with
a PWHT above the upper transformation temperature or
when an austenitic or P-No. 10H material is solution annealed
after welding.

There is no statement about thickness of test coupon which is related to impact test.

Could you give me more detail explanation ?

 

[CWEng]

See the essential variable table for the SMAW process. QW-403.6 is referenced as a supplementary essential variable, which means it applies whenever impact testing is required. A >19mm test plate will qualify to YOUR maximum thickness. Meaning it will get you past your 37mm requirement.