What is UHMW-PE?

UHMW-PE is polyethylene with an ultra-high molecular weight, often sold as PE 1000. It has very high resistance to abrasive wear, high impact strength and low friction, takes up practically no moisture, has a low density and a limited service temperature. Typical parts are conveyor guides, wear strips, buffers and star wheels. Plate is usually compression moulded, rod and profiles often ram extruded.

How does UHMW-PE behave when machined?

UHMW-PE is soft and tough. Machined, it gives long, stringy chips and a ragged burr that does not break off, and it deflects under cutting and clamping force. Its thermal expansion is high, even for a plastic, so a long dimension moves with the temperature in the shop. Pressed plates can carry internal stress and bow after machining from one side.

How does UHMW-PE work in practice?

Per kilo it is usually cheaper than, for example, PTFE; the time tends to go into finishing. A ragged burr comes off with a knife or scraper, edge by edge, unless tooling and strategy keep it down. On long parts a tight length tolerance only means something with an agreed measuring temperature. For example, a 2 m guide can change length by several millimetres over a 10 K temperature difference. A design that takes up the expansion, such as slotted mounting holes, is then often more useful than a tighter tolerance.

What is UHMW-PE often confused with?

UHMW-PE is not HDPE or PE 500: those have a lower molecular weight, cost less and wear faster. Nor is it PTFE: PTFE takes higher temperatures and harsher chemicals, while UHMW-PE is more wear-resistant and cheaper for mechanical duty.