Shear Bolt - Discountinuity Acceptance Criteria Test

Typically used on applications that require the highest level of security, these premium security bolts feature a hexagonal part attached to the top of the head of the bolt that is fastened using a standard spanner or socket: they don’t require any special tools. As the name suggests, once the bolt is tightened passed its maxinum torque limit, the hexagonal section snaps off leaving a smooth, tamper proof head with

Security Shear Bolts are suitable for high torque applications and are most often used within the construction, aerospace and automotive industries sectors. They are ideal for use with their matching Shear Nuts while fasteneing. Should there be any issue with the shear bolt requirement of « fine » thread, which in some cases can cause some proportion threads damage during the process.  We review the thread damage, by applying ASTM F788/F788M discontinued Torque test to see if thread position is acceptable and no impact to functional use.

According to ASTM F788F/788M specifications of discontinuity acceptance criteria on M8-1.25 6h requires 0.5N-m Max torque force. Hereunder are the check-step we proceed to check on threads.

1.Use adjustable GO/NO gage to check on the threads situation

2.Use VICE to hold shear bolt tied gently then apply digi- electronical wrench to check on the torque value.

3.With M8-1.25 6h accepts 0.5N-m as the max. Torque and the value we check is within the discountinuity acceptance criteria.