Your result
Locking ability |
3 out of 5 |
Reusability |
Not Applicable |
Worker safety |
3 out of 5 |
Initial cost |
High |
Lifetime cost |
Medium |
Locking ability |
3 out of 5 |
Reusability |
Not Applicable |
Worker safety |
3 out of 5 |
Initial cost |
High |
Lifetime cost |
Medium |
Locking wire, also known as safety wire or wire lock, is a mechanical locking method. It is imperative that the wire is installed so that tension in the wire only allows the bolt head/nut to turn in the direction of tightening. The tension of each section of the wire must also be locked in place so as not to be affected by the accidental loosening of another bolt head/nut in the series.
Although this method provides reasonable loosening resistance, it is time-consuming to assemble and the bolt head/nut must be drilled to create the holes for the locking wire - increasing the cost again. The only way to remove the locking wire/safety wire is to cut it away – meaning that it cannot be reused and a new piece must be installed every time the bolted joint is maintained.
Read the full version in the eBook "Why do bolts loosen?"
(A comparison between common bolt securing options)
The biggest challenge for a bolted joint, causing it to lose preload and fail, is spontaneous loosening often caused by vibrations. This Junker test shows all 5 nuts rotated loose! A steep decline in the graph indicates a failure. Read more about the Junker Test.