Basic Specifications

◎External and internal diameters of Metric screw threads must meet the requirement of ISO 965-2:1998.

◎External and internal diameters of British Standard screw threads must meet the requirement of ASME B1.1:2003.

◎External threads of counterparts must meet the tolerance of 6g ring gauge. Internal threads of counterparts must meet the tolerance of 6H bolt gauge. 

◎For internal threaded counterpart (i.e. nuts), chamfer processing is necessary and it should not have any sharp burr.

◎Coating length should be at least 4 pitches long, and the coating design should be based on the actual locking position on the counterpart as well as common application. 

◎The design of self-locking torque is based on IFI specifications. Please consult us in advance for any special requirement.

Self-Locking Torque Inspection Specification