|
|
 |
More than 500,000 types of fasteners are available today ranging from threaded and non-threaded nuts and bolts plus bolts with clips, cotter pins, etc., in metals, plastics or composites.
Most of the self-described "locking" thread fasteners utilize multiple components, incur added labor costs and often rely on misaligned threads for lock-in, but quickly lose effectiveness and denigrate. Some examples are: lock washers, tooth washers, blind thread bores filled with resilient inserts, nuts with nylon inserts that jam or deform when tightened.
Frictional locking fasteners usually require increased torque to install and consequently can mar joint surfaces. These are not reusable and require greater loads than necessary to be effective when applied to some joints. Self-locking accessories such as cotter pins, lock wires and other assemblies have the added drawback of extra installation efforts and more costly time & labor expenses. Adhesives, which are occasionally used for securing a nut and bolt can breakdown and cause corrosion at the assembly joint
|
|
|
|