Polyurethane (PU)
Polyurethane (PU) is an elastomeric plastic available from soft to very hard (about 60 Shore A to 75 Shore D), with outstanding abrasion, tear and cut resistance. It is used for rollers, wheels, seals, scrapers, bushes, pads and liners.
What it is
Cast PU parts are made by pouring liquid polyurethane into moulds or bonding it onto metal cores, such as roller shafts or wheel hubs. The hardness is chosen to balance grip, load capacity and wear.
PU outlasts rubber in many abrasive and high-load applications, and resists oils and many chemicals.
Typical applications
- PU-coated rollers and wheels
- Hydraulic and pneumatic seals
- Scrapers, wipers and blades
- Buffers, pads and bumpers
- Screen panels and wear liners
Materials & grades
- Polyester-based PU
- Polyether-based PU (hydrolysis resistant)
- PU sheets, rods and cast parts
Points to consider
- Choose polyether PU for wet/humid applications (hydrolysis resistance).
- Hardness affects grip, rolling resistance and heat build-up.
- Recoating worn roller cores is often cheaper than new rollers.
- Limited high-temperature performance.
Frequently asked questions
Is polyurethane better than rubber?
For abrasion, tear resistance and load capacity, often yes. Rubber may be better for high temperatures or high resilience.
Can worn PU rollers be recoated?
Yes. The old PU is removed and new PU is cast and machined onto the existing core.
What hardness of PU should I use?
Softer (70–85 Shore A) for grip and cushioning; harder (90 Shore A and above) for load and wear.