Overview
PEEK wear rings are precision bearing elements that guide pistons, rods, and shafts in hydraulic cylinders, pumps, and compressors. Made from polyetheretherketone, they resist high contact pressure, high temperature, and aggressive hydraulic fluids while protecting cylinder bores and rod surfaces from metal-to-metal contact.
ORRO Manufacturing machines PEEK wear rings with scarf-cut or stepped gaps and tight radial tolerances so they seat consistently and maintain concentricity under pressure. We offer virgin, carbon-filled, and glass-filled PEEK grades to balance wear resistance, thermal expansion, and cost for each application.
Material Properties
| Property | Virgin PEEK | Carbon-Filled PEEK |
|---|---|---|
| Density (g/cm³) | 1.30 - 1.32 | 1.40 - 1.42 |
| Tensile Strength (MPa) | 90 - 100 | 110 - 130 |
| Compressive Strength (MPa) | 120 - 150 | 180 - 220 |
| Max Continuous Temperature (°C) | 250 - 260 | 250 - 260 |
| Coefficient of Friction (vs. steel) | 0.30 - 0.40 | 0.20 - 0.30 |
| Limiting PV (MPa·m/s) | 0.8 - 1.2 | 1.5 - 2.5 |
| Thermal Expansion (10⁻⁶/K) | 47 - 55 | 20 - 30 |
Key Advantages
- High Load Capacity: Withstands the high side loads in hydraulic and pump service without extruding.
- Wear and Abrasion Resistance: Carbon-filled grades provide a low-friction, long-wearing running surface.
- Temperature Stability: Maintains mechanical properties to 260°C, matching demanding hydraulic duty.
- Chemical Compatibility: Resists hydraulic oils, water-glycol fluids, and many aggressive media.
- Low Thermal Expansion (filled grades): Carbon-filled grades keep clearances stable over temperature.
- Protects Cylinder Bores: Prevents metal-to-metal scuffing and extends cylinder life.
Typical Applications
Hydraulic Cylinders and Actuators
Piston and rod wear rings that guide and center moving components under high pressure.
Pumps and Compressors
Wear rings and guide rings in screw, gear, and reciprocating pumps handling hot or aggressive fluids.
Downhole and Oilfield Equipment
Wear rings for high-temperature, high-pressure tools in oil and gas service.
Machining Capabilities
| Parameter | Capability |
|---|---|
| Tolerance | ±0.02 mm (radial), ±0.05 mm (axial) |
| Surface Finish | Ra 0.8 - 1.6 μm |
| Size Range | 10 mm to 300 mm diameter |
| Key Processes | CNC turning, scarf-cut gap machining, milling |
Application Case
Hydraulic cylinder piston wear ring, carbon-filled PEEK — A hydraulic cylinder manufacturer needed wear rings that would survive 250°C hydraulic fluid and 35 MPa working pressure without extruding. ORRO machined scarf-cut carbon-filled PEEK rings to a ±0.02 mm radial tolerance, supplying 6,000 pieces in 20 days. The rings eliminated bore scuffing and extended seal life by more than 50%.
