2H Heavy Hex Nuts  Manufacturers introduces the production requirements of double-ended studs:

1. Heart hardness: The standard value is HRC28-38, and the measured value is about HRC31-33. The test is carried out on a cross-section 1-2 times the nominal diameter from the tail. If the nominal length is too short, insert it first, and then measure the hardness.

 
2. The surface hardness of the stud bolt manufacturing machine: Standard: HV600-800, the actual measured value is about HV660-710.

 
3. Carburized layer: 4#-6#0.05-0.18mm, 8#-12#0.10-0.23, 14#0.13-0.28.

    
4. The stud bolt manufacturing machine penetrates the hard layer: 4#-6#: 0.05-0.18mm 8#-12#: 0.10-0.23mm 14#: 0.15-0.28mm.

 
5. Torque: Specification, tail drill, screw, BSD type CSDINCH-LBKG-CMINCH-LBKG-CM4# (2.9) 141614166# (3.5) 242824288# (4.2) 428485510# (4.8) 6170657512# (5.5) 9210610011514# (6.3) )) 150173156180.

 
6. Screw-in test of the screw machine: Screw the self-tapping screw into the steel plate with holes for the test. The self-tapping screw forms a corresponding screw on the test board, and the screw will not deform or damage itself. Until the end tapered thread completely passes through the test board. The screw-in test is only applicable to AB, B, BP, and other types of self-tapping screws.