Anti-loosen Solution

It is possible for screws from loosening themselves despite a sufficient pre-tensioning force, because of vibration and dynamic stresses.

The cause of screws loose is that the frictional connection between the thread and in the head or nut contact surface can be reduced considerably in the event of axial vibration stress.

If force happened to a perpendicularly to the screw axis, the smallest relative slippage will occur between the stressed parts, which can result in the screws being completely loose when a full pre-tensioning force is applied.

There are various types of screw fasteners and/or parts with additional features designed to prevent loosening

1)      Use Locking mechanism on the contact surface

ABS Metal produce different kinds of locking teeth or Nibs, when locking to the contact surface, locking teeth, which have steep edges that burrow into the surface material in the unscrewing direction of the screw, or symmetrical locking ribs, which effectively maintain the pre-tensioning force on hard and soft materials, are used.

 

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  Crimptite Serration    Anti-Locking Serration     6 Half-Moon Serrrtion     Locking Serration    Straight Serration 

 

2) Change the thread profile for round to triangle

Thread is Tri-lobe (triangular) shape. This thread is constructed with  angle of 60 deg but not round., which gives an excellent vibration proof and shock resistance by improving the lock action due to external thread interfering into internal thread, when this screw is fastened into tapped internal thread.

3) Nylon Patch  & ND Patch Solution

There are a screw coated with a microcapsule in which is sealed an epoxy-based adhesive. When the screw is screwed into a female thread, the capsule is destroyed, and the adhesive oozes out, to provide a high fastening force with hardening.