EPEN · Sliding bearing family · Size and duty to be specified
EU multilayer bushing
A steel-backed, porous-bronze and PTFE-mixture sliding bearing family. Selection starts with the shaft and housing, then checks the combined load, motion and temperature of the actual application.
Read the bearing from the shaft outward
The layer structure explains the family; it does not specify a finished size.
- PTFE-mixture sliding surfaceThe published top-layer thickness is 0.01–0.03 mm. EPEN describes transfer of some surface mixture onto the mating surface during normal operation. This is the manufacturer’s description, not a measured film on your shaft.
- Porous bronze intermediate layerThe manufacturer describes a sintered layer that supports the self-lubricating mixture.
- Steel backing and outer coatingThe backing is described as supporting load and thermal conduction; the structure also names a copper/tin layer. Confirm the exact construction and corrosion requirements for the quoted variant.
These descriptions come from the EU family page [1]. The listed EU, EU-F, EU-WC and EU-S headings are size/form routes, not one interchangeable order code. Request the drawing and selected construction rather than ordering simply “EU”.
Evaluate a duty point, not a row of maxima
Load and speed interact.
| Published characteristic | EU family value | How to use it |
|---|---|---|
| Static load maximum | 250 N/mm² | Do not treat this as a dynamic-load limit. |
| Dynamic load maximum | 140 N/mm² | Check motion, temperature and combined PV separately. |
| Dry-running speed maximum | 2.0 m/s | Not permission to combine this speed with maximum dynamic load. |
| Continuous / short-term PV | 1.8 / 3.6 N/mm² · m/s | Obtain a definition of allowable short duration and the thermal conditions. |
| Friction / temperature range | 0.03–0.25 / −195 to 280 °C | Manufacturer family ranges, not guaranteed friction or simultaneous duty at every temperature. |
Values are supplier-published [1]. EPEN’s design page defines specific load as load divided by projected bearing area, and PV as specific load × sliding velocity. It also names motion-generated heat, mating surface, housing and lubrication among life factors. [2]
Why checking two limits independently can mislead
An editorial arithmetic example: a specific load of 10 N/mm² and sliding velocity of 0.2 m/s give PV = 2.0 N/mm² · m/s. Both numbers are below the separate dynamic-load and dry-speed maxima, but their product exceeds the published continuous PV limit of 1.8. This is a screening illustration, not an approved application or an EPEN test. Being below PV alone likewise does not establish suitability.
For a real assessment, provide the load history, sliding velocity or motion description, duty cycle, temperature and cooling path. Keep oscillating motion, start-stop peaks and sustained rotation distinct. Do not turn a short-term family limit into a continuous service rating.
Check fit in its installed condition
A free wrapped bushing is not a closed cylindrical reference.
EPEN warns that wrapped bushings are not closed in the free state and cannot be accurately checked for ID/OD by an ordinary free-state measurement; it calls for appropriate gauges and test equipment. [2] Agree the installed housing condition and measurement procedure with the supplier before accepting parts by a loose-bushing caliper reading.
Shaft and housing package
Submit shaft diameter and tolerance, housing bore and tolerance, bearing length, required running clearance and assembly drawing. Ask for the selected variant’s mating-surface and installation instructions. The family page does not supply one universal shaft/housing fit for every size.
Environment and maintenance
The product page’s chemical matrix rates different constructions differently, including seawater exposure. Specify the actual fluid and exposure instead of assigning a blanket corrosion rating. A “maintenance-free” family description does not remove housing, contamination or mating-surface checks. [1]
Compare bearing offers at the same definition
Keep size, backing/coating, sliding layer, installed fit, duty and inspection method together. Include traceability and agreed dimensional reporting for the order. A similarly sized multilayer bushing from another supplier is not automatically interchangeable merely because both contain PTFE.
Questions that change the selection
Can I run at maximum load and maximum speed?
The combined duty needs a PV and thermal assessment. The listed maxima do not define one permissible operating point. Ask EPEN to respond to the actual load, motion and environment.
Can I check the inside diameter before pressing it in?
The manufacturer specifically warns about free-state wrapped-bushing measurement. Obtain the gauge/installed measurement method for the ordered variant.
Does the temperature range establish service life?
No lifetime is established for your assembly. Load, PV, housing, clearance, mating surface, exposure and duty still need a supported assessment.
Send the size and operating duty
Make the family into an orderable specification.
Sources & review
- EPEN EU bushing family ↗
Layer structure, material characteristics, chemical matrix and size-family identifiers. Read directly 11 October; maxima are separate supplier limits, not a combined approved operating point.
2026-10-11 - EPEN bearing design and wrapped-bushing measurement ↗
Load/projected-area and PV definitions, service-life factors and the warning against free-state ID/OD measurement. Read directly 11 October. Some diagram content is not available as text.
2026-10-11
Specifications come from the manufacturer’s published information and the sources above; buying advice is written by CivilEquip with AI assistance. Ask the manufacturer to confirm the data for your configuration. Editorial policy · Report a correction.