SA 234 Grade WPB Elbow - Tensile Requirements
SA 234 Grade WPB Elbow - Tensile Requirements
(OP)
Good Day Everyone!!!!
Material Description - SA234 Gr.WPB, Hot formed between 780-980 Degree Celcius
In MTC it has been mentioned as the Tensile test (Mechanical Properties) carried out on Raw Material.
As per SA 234 Tensile requirements Cl.9.0 (9.1 to 9.4), I am bit confused and would like to know whether the Tensile test coupon to be taken from the Finished fittings or from the Raw Material used to manufacture the fittings.
Thanks in advance for reply.
Material Description - SA234 Gr.WPB, Hot formed between 780-980 Degree Celcius
In MTC it has been mentioned as the Tensile test (Mechanical Properties) carried out on Raw Material.
As per SA 234 Tensile requirements Cl.9.0 (9.1 to 9.4), I am bit confused and would like to know whether the Tensile test coupon to be taken from the Finished fittings or from the Raw Material used to manufacture the fittings.
Thanks in advance for reply.





RE: SA 234 Grade WPB Elbow - Tensile Requirements
9.4 Records of the tension tests shall be certification
that the material of the fitting meets the tensile requirements
of this specification provided the heat treatments are the
same. If the raw material was not tested, or the fitting is
not in the same condition of heat treatment, the fitting
manufacturer shall perform the required test on material
representative of the finished fitting from each heat of
starting material.
So, you need to determine what heat treatment was performed on the raw material so that the tensile test results represent the material condition of the finished fitting. For example see below after hot working,
7.2 Hot-formed WPB, WPC, and WPR fittings
upon which the final forming operation is completed at
a temperature above 1150°F [620°C] and below 1800°F
[980°C] need not be heat treated provided they are cooled
in still air.
RE: SA 234 Grade WPB Elbow - Tensile Requirements
Thanks Sir for your reply.
Most of the MTCs we have reviewed it mentions only the Starting material (Pipe, Bar or Plate), it doesn't mention the condition of Raw Material used to manufacture the fittings as it is not an requirement to mention in the MTC as per SA234 Cl.17.0 Certification.
MTC only gives a detail of final product (Fittings) Hot forming temperature details or Heat treatment Temperature and Time details if Heat treated.
In this case we might have to ask an clarification to the mill regarding the forming temperature of raw material used to manufacture the fittings.
Could you please let me know whether my understanding is correct.
From your above reply we understand that the tensile test coupon to be taken from the raw material and not from the fittings.
RE: SA 234 Grade WPB Elbow - Tensile Requirements
RE: SA 234 Grade WPB Elbow - Tensile Requirements
I have plate MTC which is S275JR+N, N I guess stands for Normalizing. Fitting made out of these plate are certified to SA234 WPBW and all are hot formed between 780-980 Degree C and in some cases these fitting are stress relived (Above 19mm as required by B31.3).
Manufacturer has performed tensile test on specimen taken from plate. As I understand from Clause 9.4 of SA234, specimen shall be in same condition of heat treatment as of finished fitting, but in this case fitting are hot formed or stress relived (n case of thickness is above 19mm) and specimen tested is in normalized condition.
Is it correct? I think it is not. if it is not could someone please advise what treatment can be imparted to specimen from plate.
Would appreciate you comment.
Regards
MS
Regards
MatSci1254
RE: SA 234 Grade WPB Elbow - Tensile Requirements
RE: SA 234 Grade WPB Elbow - Tensile Requirements
one of answer i got is that the stress relliveing does not alter the mehcnial properties and since the fitting are normalized formed therefore it is in same condition of heat treatment as of the plate and hence test on fittings are not required, the test conducted on plate sample are representative of the fitting propeties.
Regards
MatSci1254
RE: SA 234 Grade WPB Elbow - Tensile Requirements