Further information:
material data
Specifications:
Sliding surface: | PTFE + fillers
Carrier material: | steel, tinned
Dynamic resilience: | ≤ 140 N/mm²
Static load capacity: | ≤ 250 N/mm²
Sliding speed: | ≤ 2.5m/s
Coefficient of friction: | 0.02 - 0.20µ
Max PV value: | 1.8N/mm² xm/s
Temperature load: | -200 to +280 °C
Services: | maintenance free
Housing bore tolerance: | H7
Tolerance after installation: | H9 (after installation in the middle of H7)
Shaft Tolerance: | f7 or f8
Shaft material: | Steel, hardened or unhardened, surface roughness Rz < 2-3
Interesting facts in the Avantgarde plain bearing blog
FAQs
What are metal-polymer plain bearings?
Metal-polymer plain bearings are composite material systems with a metal backing, a sintered bronze intermediate layer and a sliding layer made of PTFE or other polymers with fillers. These are available in bushes, flanged bushes, strips, thrust washers and various special shapes.
How do self-lubricating, maintenance-free plain bearings work?
In contrast to roller bearings, there is no point load in maintenance-free plain bearings. The design is more compact and the surface pressure is absorbed over the entire contact surface. As a result, significantly higher loads can be accommodated at low to medium speeds. The permissible speed always depends on the surface pressure or bearing load. As a guideline, the pV value is used as a reference. This results from multiplying the surface pressure by the prevailing sliding speed = peripheral speed. If the permissible pV value is exceeded, the frictional heat can usually no longer be dissipated quickly enough and the bearing point overheats.
In which areas of application are metal-polymer plain bearings used?
Metal-polymer plain bearings are used in all areas of industry within the scope of the above-mentioned areas of application.
What advantages do metal-polymer plain bearings offer compared to conventional plain bearings?
Please read our detailed blog post!
How long do self-lubricating, maintenance-free metal-polymer plain bearings last?
The service life of plain bearings depends on a variety of factors, such as the degree of contamination, ambient temperature, type and duration of the work cycles and many more. Depending on the requirement specification, plain bearings can be in continuous operation for 1 year or 15 to 30 years. Crucial here are above all the friction kilometers under the given application conditions. We would be happy to provide you with a service life estimate for your application.
Can metal-polymer plain bearings be used in water or lubricating environments?
Self-lubricating steel/PTFE or bronze-PTFE composite plain bearings can also be used in a humid environment and in a lubricating environment! The basic requirement for use with lubrication is that once a plain bearing with a PTFE sliding layer has been lubricated, it should be permanently relubricated. Otherwise there is a risk that abrasive particles from the environment will mix with the lubricant and thus form a grinding paste that will cause the bearing to wear out prematurely.
What load capacities and sliding speeds are possible with metal-polymer plain bearings?
Steel/PTFE composite plain bearings achieve permissible surface pressures of 250 N/mm². The bronze/PTFE composite variant is around 140 N/mm², which is due to the lower static load capacity of bronze compared to steel.
What are the assembly and installation requirements for metal-polymer plain bearings?
Please read our blog on the subject of plain bearing assembly!
How can the correct dimensions and tolerances for metal-polymer plain bearings be calculated?
The dimensions result from the strength requirements of the overall construction and from the bearing load, which in turn specifies the required minimum contact area. As a rule, the required diameter is far below that of a roller bearing. So this offers potential for a compact design and weight savings of the overall construction.
What are the key parameters to optimize the performance of metal-polymer plain bearings?
To optimize the performance of metal-polymer plain bearings, the following parameters should be considered:
a) Selection of the right plain bearing material: The material combination of carrier backing, intermediate layer and sliding layer should be tailored to the specific requirements of the application.
b) Sliding speed and surface pressure: Compliance with the permissible pV values (product of surface pressure and surface pressure) is decisive for the service life and performance of the bearing.
c) Lubrication: With self-lubricating slide bearings, continuous lubrication is not necessary. However, once lubricated, this should be maintained permanently to avoid premature wear.
d) Shaft and Housing Tolerances: Proper fit and tolerances between the shaft, sleeve bearing and housing are critical to optimal bearing performance.
e) Cleanliness: A clean mounting environment and avoidance of contamination in the journal bearing will help improve bearing performance.
Are there special cleaning or maintenance requirements for metal-polymer plain bearings?
Because metal-polymer plain bearings are self-lubricating and maintenance-free, special cleaning or maintenance requirements are not usually necessary. However, in heavily polluted or corrosive environments, regular cleaning or anti-corrosion measures may be useful to maintain bearing performance and life.
How does temperature affect the performance of metal-polymer plain bearings?
Temperature can have a significant impact on the performance of metal-polymer plain bearings. High temperatures can cause the PTFE or other polymers in the sliding layer to lose their lubricity or degrade. Thermal expansion of the metal and polymer can also lead to fit problems or increased wear. It is important to consider the temperature limitations of the bearing material chosen and take cooling measures where necessary to optimize bearing performance and life.
Can metal-polymer plain bearings be custom made?
Yes, metal-polymer plain bearings can be custom made. Depending on the requirements of the application, custom dimensions, material combinations or special sliding layer compositions can be developed to ensure the optimal performance and service life for the specific application.
When manufacturing customer-specific metal-polymer plain bearings, the following points should be observed:
a) Bearing performance requirements: The specific performance requirements such as load carrying capacity, sliding speed, temperature range and wear resistance should be well defined in advance.
b) Ambient conditions: The ambient conditions, such as dirt, moisture or aggressive media, should be taken into account when selecting the materials and designing the bearing.
c) Geometry and dimensions: Custom bearings can be manufactured in various shapes and sizes to suit the installation requirements and space constraints of the specific application.
d) Manufacturing Tolerances: Depending on the application, tighter manufacturing tolerances may be required to ensure an optimal fit and even load distribution in the bearing.