Features
There are several options for bolt design. If a joint suffers from vibrations, a prevailing torque feature could be added to avoid self-loosening.
A painted weld nut might cause cross threading due to weld splatters or too much paint remaining in the nut thread. In most cases, there is a feature that will help the joint overcome these obstacles.
“Patch” is the common word for pre-applied, dry-to-touch thread features.
The three most used categories are:
- Thread Locking
- Thread sealant
- Lubrication
Thread Locking
Prevailing torque feature.
Nylon patch creates friction due to radial force
Locking fluid
Micro-encapsulated two-component glue. The micro-capsules crack and let out the curing agent when the screw is fastened.
Thread sealant
Looks like locking fluid but lacks the curing agent. Fills the void between mating threads. Lubricating at the assembly, easy to loosen.
Lubrication
“Anti-seize.” Prevent seizure at disassembly. Universal in a host application, such as exhaust manifolds.
Wax to lower friction locally. For example the thread forming lead threads of a Taptite.