Difference between SA234WP12CL1 & SA234WP12CL2 and their stress values

[coolniks37]

Hi

I have seen these 2 specs in ASME Section IIA.
There is not much difference in composition between these two. But there is a difference in tensile and yield strength values?
For CL1, section II D gives a detailed allowable stress value for various temperatures, but for CL2 it is absent

My question is
a) What is the difference between this CL1 & CL2 ?
b) Where can i get stress value for SA234WP12CL2 material and why it is absent in table 1 , section 2D ?

Pls help...

 

[metengr]

My question is
a) What is the difference between this CL1 & CL2 ?
b) Where can i get stress value for SA234WP12CL2 material and why it is absent in table 1 , section 2D ?

(a) A review of ASME SA 234 material specification reveals the differences;

Cl1 UTS YS
60-85 Ksi 32 Ksi min

Cl2 UTS YS
70-95 Ksi 40 Ksi min

(b) The allowable stress values have not been published because this class of material was not requested to be used as B&PV pressure retaining material, and cannot be used until a code case is developed by a user.

 

[ijzer]

CL2 is not allowed to be used in ASME 1 or ASME VIII.

ASME B31.3 however does allow CL2 , so you can find the allowable stress at temperature in the B31.3 stress table.