B7 stud bolts manufacturing process 1

[Forrest79]

Hey guys,

recently we meet some problem about stud bolts and nuts. supplier provide B7 stud bolts, the bolts are thread rolled, then heat treated, I wonder during the quenching in Oil, may there be problems on the thread top, will there be some cracks, also during the heat treatment there must be some lost of carbon, it will affect the mechanical properties.

so my question is that is it accepted to do quenching heat treatment after the thread forming.

 

[CoryPad]

Supplementary Requirement S11 of ASTM A 193 covers thread forming after heat treatment. If you don't specify this requirement, then the supplier can make parts with threads formed before heat treatment.

Parts produced by a high-quality process should not have problems with cracking or decarburization. The limits for these are identified in ASTM A 962.