What is a Zerk fitting?
Grease fittings, also known as zerk fittings or grease nipples, serve as lubrication points on bearing housings or other mechanical components. Their design provides a secure connection to a grease gun coupler for delivering precise amounts of grease into bearings and other moving systems.
Why are they called Zerk fittings?
The Zerk design, named after Oscar Zerk, used a fitting much smaller than the Alemite pin-type and did not lock the hose coupler or hand gun and fitting together. Instead, the seal between them was maintained by the pressure of a pushing action when the operator applied the coupler to the fitting.
How do you change a grease fitting?
Grease fittings are available at auto parts stores.
- Clean the area around the broken grease fitting with a rag.
- Place an appropriate size open-end wrench around the hex nut of the fitting.
- Thread a new grease fitting into the grease hole until you can no longer turn it by hand.
What sizes do grease Zerks come in?
Grease fittings come in many different styles. There are two grease fittings that are very common. These are the 1/4″-28 thread and the 1/8″ NPT thread. However, there are other less common grease fitting threads in use.
What are the types of grease fittings?
There are three major thread types for grease fittings: metric, taper or parallel, and unified. M5, M6, M7, M8, and M10 are common metric threads. British standard pipe (BSP), pipe thread fine (PTF), and national pipe thread fine (NPTF) fittings use tapered or parallel threads.
Are all grease gun nipples the same size?
Are all grease guns the same size? There is effectively just one size. There are some other weird ones out there, the common being button head I believe, but if it looks like a standard grease zerk it is going to be the standard size.