When are impact tests required

By Flash Date 02-18-2008 10:12

Hi All
I am doing some work to B31.3
and am wading through the document to determine when and where impacts are required
can anyone enlighten me as to the process of determining when impacts are required and not required using A106Grb and A333 materials
thanks in advance
R
Flash

By NDTIII

Date 02-18-2008 12:28 Edited 02-18-2008 12:32

Look at Chaper III, Section 323.2. It lists all of the toughness test requirements for low temperature service.
Basically if you are designing a system for temperature below the minium temperature allowed by Table A1 or Fig. 323.2.2A you must do impact tests. Doesn't matter if it's A106 Gr B or A335.
Be careful with the A335. It is P5 material and can have anywhere from .5% Cr all the way up to 9% Cr. Depending on the Grade and/or P No. These not only require impact tests for low temperature service but also require preheat, PWHT and radiography must be performed after final PWHT (B31.3, 341.3.1 (b)).
Preferrably after about 48 hours.

By Flash Date 02-18-2008 18:53

thanks NDT111
Table A1 indicates that any temp less than -29C for A106GrB requires impacts
consumables need to be classified at the temp eg. grade3
R
Flash

By NDTIII

Date 02-19-2008 03:43

You're welcome but also remember that you must perform your impact tests at the lowest design temperature you will encounter.