Tribological Components, types of plain bearings
Types of plain bearings, Plain bearings, also referred to as bushes, bushings, or sleeve bearings, are usually cylindrical in shape and contain no moving parts.
Types of Plain Bearings (Bushings), Plain bearing materials in comparison: metal-polymer plain bearings
Sliding-bearing plain bushing suppliers, let’s take a look at the so-called metal-polymer plain bushing bearings. What are metal-polymer plain bearings, Types of Plain Bearings? How do they differ from other types of bearings? What are they particularly suited for, and when is it best not to use them?

We take a closer look at metal-polymer plain bearings types and weigh up the specific advantages over other plain bearing bushing materials.
Metal-polymer plain bearings bushing type
Metal, more precisely steel, bronze, copper or brass, is a common material in the field of plain bearings due to its load-bearing capacity and thermal conductivity. In order to improve their sliding properties and wear resistance, plain bearings made of these materials are usually lubricated. The problem is: as far as production technology is concerned, greases or lubricants require a complex feeding system at the bearing points (lubrication grooves and lubrication nozzles, central lubrication). In addition, the lubricant often enters the environment and contaminates the surrounding components or products. In the search for alternative technologies to reduce the coefficient of friction, special plastic with excellent sliding properties was finally found at the beginning of the 20th century: polytetrafluoroethylene, or PTFE for short, better known by the trade name Teflon from DuPont.

That Teflon not only had excellent sliding properties but was also very soft. Therefore, if it is possible to combine the stability of metal with the sliding properties of a plastic such as PTFE, lubrication can be eliminated. The concept: a wear-resistant metal shell protecting an embedded PTFE layer. But how do you get such material with good sliding properties and correspondingly poor adhesion to stick to the metal?
Technical details: metal-polymer plain bearings bushing.
The greatest strength of metal-polymer bearings is also their greatest weakness. Lubricious or better sliding films are made of particularly slippery and correspondingly soft plastics. These include PTFE, but occasionally other plastics such as polyoxymethylene (POM) as well. With a clever combination of different manufacturing methods and materials, these plastics are successfully fixed in protective metal sleeves.
Metal-Polymer Bearings Bushing

The PTFE layer is very thin compared to the wall thickness of the metal sleeve, and it is not directly coated on the steel. Instead, it is coated on a porous layer of sintered bronze, which in turn adheres to the steel.
Advantages of metal-polymer plain bearings
The advantages and disadvantages of this type of plain bearing come from this multilayer construction. Main advantages: Metal-polymer plain bearings – at least those with a PTFE sliding layer – are operated “dry”, i.e. without grease or oil lubrication. the PTFE layer ensures a relatively low coefficient of friction. Due to the high metal content, heat dissipation is also better compared to all-plastic plain bearings. Last but not least, the load-bearing capacity is very high due to the use of steel. Static loads, in particular, can be absorbed very well in this way.

The stainless steel roller bushing of the metal-polymer bearing is the metal bearing material used is easily not prone to corrosion and the bearing is lead-free and RoHS certified.
Due to the manufacturing process, the plain bearing design can be cut or bent from the rolled sheet metal shape: straight bushing, turned over, slider
Advantages of metal plain bearings.
Can withstand high static loads
Relatively good heat dissipation
Low coefficient of friction (PTFE)

Looking for the best plain bearing? We would be happy to help you!
In addition to metal-polymer plain bearings, there are other types of bearings that offer different advantages.
What Are Bearings? – Choosing the right plain bearing
Plain bearings, also referred to as bushes, bushings or sleeve bearings, are usually cylindrical in shape and contain no moving parts.

Metal-polymer plain bearings
Engineered plastics bearings
Composite bearing bush
Monometallic, bimetallic, and sintered bronze plain bearings

A plain bearing, also known as bushing, is a mechanical element used to reduce friction between rotating shafts and stationary support members. Typically, bushing relies on soft metal or plastic and an oil film to support the rotating shaft on the hardened shaft journal. Plain bearings are used primarily in machinery that has a rotating or a sliding shaft component. Also called journal bearing, sleeve bearings, or sliding bearings, plain bearings have no rolling elements. Some are made of relatively soft metal, such as Babbit, to protect the shaft journals. They are made of other materials as well, depending on the application and load requirements. Other bushings may be used for alignment jigs in drilling operations.

Depending on the type of contact between the parts:

Plain or friction bearings
Rolling bearings

Based on the lubrication system employed, there are three basic types of plain bearings:

Self-lubricating bearings
Regularly lubricated bearings
Continuously lubricated bearings

Plain bearings Advantages:

They are lighter.
Lower costs
The longer fatigue-free service life of their elements.
Lighter weight.
Less noisy.
They require less radial space since they are built with thin walls.
Their installation is simpler.
Using self-lubricating bearings, lubrication procedures are not required.
They allow for higher rotational speeds.
Greater shock resistance.