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Up Topic American Welding Society Services / Technical Standards & Publications / WPS qualification CVN riquired
- - By gastonM (**) Date 03-06-2013 18:13
hello everybody

I need opinions.

2 PQR.

1- Thickness 25mm without CVN test.

2- Thickness 3mm. with CVN test.

may support a WPS

Thickness 3 to unlimited, when, CVN is required?

If the awnser is yes.

Need PQR 2, record tension test and bend test ?
Parent - By S. WINAI (**) Date 03-07-2013 08:28
My opinions: Yes and both PQR need to record.
- - By 803056 (*****) Date 03-07-2013 21:05
What welding code are you working with and 3 mm sounds very thin to require CVN testing.

Al
Parent - - By gastonM (**) Date 03-08-2013 11:01
It was only an exercise. I saw that ABS (generally) do not require cvn for plates less 6mm in thickness, but i didnt see the same in D1.1. I am thinking in qualify 6mm and thicker, because, i dont hope that  thin plates can pass the test, due the mill test certificates shows, that thin secction, dont pass.
Al, or someone with experience in mining projects, can tell me what is the typical minimum thickness that require CVN test.

Thanks in advance

Regards.

Gastón.
Parent - - By 803056 (*****) Date 03-08-2013 14:45
Notch toughness is usually required when the structure is subjected to impact loads at low temperatures. The design engineer has to determine when notch toughness testing is ncessary, he mustspecify the minimum absorbed energy, and the required test tmperature. The engineer must also specify what portions of the welded joint are to be subjected to notch toughness testing, i.e., the weld, HAZ, or base metal.

If notch toughness testing is required, the designer should specify base metal and welding consumables that have been qualified for notch toughness by the manufacturer. The WPS is then qualified with CVN in mind. As stated, the designer must provide specific instruction and information in order for the WPS to be qualified appropriately.

There is no one standard value or set parameters when CVN is required by the structural weldng codes.

Best regards - Al
Parent - By gastonM (**) Date 03-08-2013 19:27
Al, I was involved in a project in what specifications established, were: "all welds,are fracture critical, and all base metal must have an absorved energy of 34J at +4ºC. It's really conservative, but if I can reach this requisite, probably could satisfy other future project requirements, thus i dont need to be qualifying for every project. But i am thinking that in thin plates this requirement is not reasonable,due the rolled sections less 6mm in thickness, cannot achieves those absorved energies, so could ask engeneer revise his requirement, but only with fundaments.

Regards.

Gastón.
Parent - - By S. WINAI (**) Date 03-09-2013 06:24
Hi Al,
If  the design temperature (services temperature) for structure is 0 degree C. and specified request that all material to meet ABS sharpy V-Notch impact requirements. Let said if i want to qualified WPS for ABS steel grade FH36( CVN -60 degree C  spc.)
I still need to do  CVN test at -60 degree to qualified this WPS?
Thanks,
winai
Parent - By 803056 (*****) Date 03-09-2013 07:08
I don't have a copy of the ABS rules, so I am not able to provide a response that is based on ABS requirements.

Al
Up Topic American Welding Society Services / Technical Standards & Publications / WPS qualification CVN riquired

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