Overview
PU (polyurethane) scraper blades are tough, abrasion-resistant wiping elements used to clean and contain material on conveyor belts, rollers, and moving surfaces. Polyurethane’s outstanding wear resistance, high tear strength, and tunable hardness make scraper blades that hold a sharp wiping edge far longer than rubber or metal alternatives.
ORRO Manufacturing machines PU scraper blades to precise edge geometry and thickness, holding the straightness and edge quality needed for effective wiping. We cast and machine polyurethane in hardnesses from 70 to 95 Shore A, and can produce segmented or continuous blades with mounting holes and bevels to match your scraper assembly.
Material Properties
| Property | Cast Polyurethane |
|---|---|
| Density (g/cm³) | 1.10 - 1.25 |
| Tensile Strength (MPa) | 30 - 50 |
| Hardness (Shore A) | 70 - 95 |
| Tear Strength (kN/m) | 40 - 80 |
| Continuous Service Temperature (°C) | -30 to +80 |
| Abrasion Resistance | Excellent |
| Oil Resistance | Good |
| Resilience | High |
Key Advantages
- Superior Abrasion Resistance: Maintains a sharp wiping edge far longer than rubber.
- High Tear Strength: Resists chunking and edge damage in rough service.
- Tunable Hardness: Durometer can be matched to belt speed and the material being scraped.
- Good Chemical Resistance: Withstands many industrial fluids and slurries.
- Low Friction: Reduces drag and wear on the belt or surface being wiped.
- Precision Edge Geometry: Machined bevels and straightness ensure consistent cleaning.
Typical Applications
Conveyor Belt Cleaning
Primary and secondary scraper blades that remove material carryback from belts.
Roller and Drum Wipers
Wiper blades that clean rollers and drums in printing, coating, and packaging lines.
Industrial Scrapers and Plows
Wear blades for plows, chutes, and material-diversion equipment.
Machining Capabilities
| Parameter | Capability |
|---|---|
| Tolerance | ±0.1 mm (thickness), ±0.2 mm (edge profile) |
| Hardness Range | 70 - 95 Shore A |
| Size Range | Up to 2,000 mm length |
| Key Processes | Casting, CNC machining, grinding, edge beveling |
Application Case
Primary conveyor scraper blade, 85 Shore A PU — A bulk-material handling operator needed scraper blades that would resist abrasion from wet iron ore and hold a sharp edge for at least six months. ORRO cast and machined 85 Shore A PU blades with a machined bevel edge, supplying 600 sets in 16 days. The PU blades lasted over nine months, more than double the previous rubber blades.
