Manufacturer of Self-lubricated dry sliding bearings material in flat strips, a composite structure flat sheet consists of a carbon steel backed/bronze backed/stainless backed, an intermediate layer of bronze, PTFE/POM based sliding lining.We maintain a wide selection of standard strips wall thickness and custom sizes to fit all of your bushing & sliding bearings application needs.
Comparison of sliding bearing strip plate materials: metal-polymer plain bearings plates
What are metal-polymer plain bearings strip & plate?
Metal-polymer plain bearings and weigh the specific advantages and disadvantages compared to other plain bearing materials.
Why are there metal-polymer plain bearings?
Metals, more precisely steel, bronze, copper or brass, are common materials in the field of plain bearings due to their 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: As far as production technology is concerned, grease or oil lubrication requires the use of complex oil supply systems in the bearing points (lubrication grooves and grease nipples, central lubrication). In addition, lubricants often enter the environment and contaminate surrounding components or products. The search for alternative technologies to reduce the coefficient of friction finally led to the discovery, in the early 20th century, of a special plastic with excellent sliding properties: polytetrafluoroethylene, or PTFE for short.
The problem: Teflon not only has excellent sliding properties, but is also very soft. Therefore, if the stability of metal could be combined with the sliding properties of a plastic such as PTFE, lubrication could be eliminated. Concept: A wear-resistant metal housing protects the embedded PTFE layer. But how do you make this material, which slides well and therefore has poor adhesion, adhere to metal?
Technology for excellence: metal-polymer plain bearings
Metal-polymer bearings PTFE, polyoxymethylene (POM). Through a clever combination of different manufacturing methods and materials, the fixation of these sliding layers in the protective metal sleeve is successful.
Metal-polymer bearings strip、Metal-polymer sliding bearing strip
Compared to the wall thickness of the metal sleeve, the PTFE layer is very thin and is not directly coated on the steel. Instead, it is applied to a porous layer of sintered bronze, which in turn adheres to the steel.
Advantages and disadvantages of metal-polymer plain bearings
The advantages and disadvantages of this type of plain bearing strip stem from this multilayer structure. The main advantage: metal-polymer plain bearings – at least those with a PTFE sliding layer – operate “dry”, i.e. without grease or oil lubrication. ensures a relatively low coefficient of friction. Due to its high metal content, it also dissipates heat better than all-plastic plain bearings. Last but not least, the load-bearing strip capacity is very high due to the steel used. Static loads can be absorbed particularly well in this way.
The main disadvantages of metal-polymer bearings are the susceptibility of the used steel to corrosion and the presence of lead in some variants, which makes them ineligible for RoHS certification. In addition, the weight is higher compared to all-plastic plain bearings.
However, the main limitation is precisely the PTFE layer that is necessary for good sliding performance. If this extremely thin layer is damaged or scratched due to improper mounting, or if it wears out due to increased wear, the shaft to be supported runs on metal. Worn bearings will not only cause a little increase in bearing clearance, but will often directly damage the shaft, which is usually relatively expensive. In addition, due to the manufacturing process, the design of plain bearings is limited to shapes that can be cut or bent from rolled sheet metal.
- High static loads possible
- relatively good heat dissipation
- Low coefficient of friction (PTFE)
- Thin and sensitive PTFE layer
- Prone to corrosion
- Some variants are not RoHS compliant
- Relatively high weight
- Restricted design
Looking for the best plain bearing? We would be happy to help you!
In every plain bearing strip application, these advantages and disadvantages must be weighed against each other. By no means all of these aspects come into play in every application. In addition to metal-polymer plain bearings, there are other bearing types with different advantages and disadvantages.
Different types of plain bearings are suitable for different applications with different specifications. Often there is application overlap – but it is not uncommon for there to be significant differences in service life and performance.
Our application specialists will be happy to advise you and work with you to design your bearing points. We will determine the sliding bush with the best service life, cost and performance ratio for you by phone, digital access or at your site. Free of charge and without obligation. Everything from one source.