Cast polyurethane belt scrapers (blades) clean the return side of conveyor belts in mining, ports, cement and bulk handling. Cast PU is used because it holds a working edge far longer than rubber, resists abrasion and oil, and can be tuned from tough to resilient by hardness. Blades are cast on a PU elastomer casting machine — we build the machine; you supply the PU system.
What You Need
- PU elastomer casting machine (TDI or MDI system capable)
- Blade moulds — per blade profile and size
- Steel inserts/backing where the design bonds PU to a carrier
- PU system + primer — sourced by you
The Process
- Insert prep — degrease, blast and prime the steel carrier for a reliable PU-to-steel bond.
- Conditioning — preheat mould; hold components at set temperature.
- Meter, mix, pour — fixed-ratio dosing; fill to avoid voids at the working edge.
- Gel, demould, post-cure.
- Trim and inspect the edge — the edge is where the blade earns its life.
Key Parameters
- Hardness — scraper blades are commonly Shore A 85–95; harder for abrasive ore, more resilient for sticky material
- Ratio accuracy — soft spots at the edge cause early failure
- PU-to-steel bond — primer and blast profile decide whether the blade delaminates
- Post-cure — needed for full abrasion and tear resistance
Which Machine
We supply the TDI system casting machine for CPU scrapers. See the full PU elastomer casting machine range.
FAQ
What hardness for a belt scraper blade?
Usually Shore A 85–95. Harder blades last longer on abrasive ore; slightly softer, more resilient blades handle sticky or wet material better.
Why TDI systems for scrapers?
TDI-based cast elastomers are widely used for high abrasion and tear resistance, which is what a scraper edge needs. MDI systems are also possible; we advise per your target.
Do you supply the PU material?
No — we build the casting machine. You run your own or sourced PU system.
Tell us your blade profile, hardness and output — we will propose the right casting machine and quote.