Bushings, also known as bushes, are self-reliant plain bearings that are placed into a casing to provide a bearing surface.

Common models will comprise of sleeve bushings and flanged bushings. Sleeve bushings are only a "sleeve" of material with an inner diameter, outer diameter and length. Flanged bushings are a sleeve bushing with a flange extending outward from the inner width. The flange is used to confidently locate the bushing when it is installed.

Spring-steel-bushings are made from hardened boron-alloyed spring-steel while linear bushings are not normally pushed into a casing, but are secured with two retaining rings. This is normally a more reliable method of preserving the bushing, as the energy acting upon the bushings could force it out.

An inner tension bushing is used for swinging or slow rotating movements and can be heat-treated for extra hardness whereas an outer tension bushing which is put together on to the shaft, allows the bushing to rotate without restraint in the casing because of the increased forces which are retracted towards the shaft.

Inner tension bushing, with thrust pads is a unique bushing developed for the specific forces that are permissible in the casing. This of course depends on the amount of fluids such as Oil, Petroleum, Natural gas or refining substances that flow through it. This bushing is particularly selected because it is easy to repair.

There are a series of tension bushings that are perfect for use in many industries like the Oil refining, petroleum, Natural gas and refining industries and also for applications that include heavy loads, or have slow movements during rough conditions, or where vibration, deterioration or abrasion can be a threat.

Tension bushings are infused with corrosive resilient materials and made of and alloyed steel which includes boron which hardens steel. Boron alloyed steels are durable and scratch resistant and easier to work with compared to other alloyed steels. They have extra strength and can easily be hardened up to greater resistances.

Other types of bushings include:

• Hardened steel bushings of various thicknesses such as, Thin-walled- and thick-walled bushings.
• Wrapped triple-layer bushings which have a plastic-inner layer for greater capability.
• Pre-lubricated plain bushings which have grease pockets in a specially treated plastic for tough locations.
• Plain bushings which have a bronze-backing instead of a steel-backing.
• Slide bushings which are made from a double layer substance. They have self lubricating and heat resistant parts and substances on the outer plane can be made from Bronze, steel or stainless steel.