PU Seals
Precision injection molded and CNC machined polyurethane hydraulic seals designed for extreme dynamic pressures up to 500 bar. Delivers exceptional extrusion resistance, outstanding tensile strength, and superior oil sealability in heavy-duty hydraulic cylinders.
Types & Configurations of PU Seals
Hydraulic Piston U-Cup Seals
Asymmetrical lip seals providing single-acting or double-acting pressure containment with zero leakage.
Hydraulic Rod Seals with Secondary Lip
Heavy-duty rod seals featuring dynamic secondary stabilizing lip preventing oil film bypass.
Snap-In & Metal-Cased Wiper / Scrapers
Tough polyurethane dirt exclusion scraper rings preventing dust, ice, and mud cylinder contamination.
Double-Acting Composite Piston Seals
Polyurethane seal ring energised by an internal NBR elastomer profile for high-pressure industrial rams.
Custom CNC Machined Hydraulic Seals
Zero-tooling rapid turnaround seals machined from solid cylindrical PU billets up to 600mm OD.
Key Industrial Applications
Specifications & Technical Details
PU Seals can be precision-manufactured in custom dimensions, wall thicknesses, cross-sections, and durometers to match your exact application specifications. Below are typical engineering cross-section drawings and technical parameters for reference.
Typical Dimension Drawings & Blueprint Cross-Sections
Technical Specifications
| Parameter | Specification / Options |
|---|---|
| Operating Pressure | Up to 500 bar (50 MPa / 7,250 PSI) dynamic pressure |
| Sliding Velocity | Up to 1.0 m/s reciprocating speed |
| Durometer Hardness | 92A, 95A Shore A and 55D Shore D high-modulus polyurethane |
| Hydraulic Media | Mineral oil based hydraulic fluids, biodegradable synthetic esters, water-glycol |
| Extrusion Gap | Accommodates up to 0.4mm extrusion gap at 400 bar without nibbling |
| Tensile Strength | > 45.0 MPa (ISO 527) |
| Operating Temp | -40ยฐC to +115ยฐC |
Material Selection & Properties
We offer specialized compound formulations tailored to chemical media, thermal extremes, static deflection, and dynamic fatigue requirements. The best material depends on your operating environment and required service life.
| Material / Polymer | Key Engineering Properties | Recommended Applications & Considerations |
|---|---|---|
| Cast Polyurethane 70A - 95A | 5x higher abrasion resistance than rubber, high load | Forklift drive wheels, heavy slurry scraper blades |
| Hydrolysis-Resistant PU (Ether) | Resists microbial attack, wet environments & water | Marine guide rollers, wastewater treatment scrapers |
| High-Resilience PU (Ester) | Superior dynamic spring properties, tear strength >60 kN/m | Die-spring blocks, metal-stamping cushions |
| Food-Grade Polyurethane | FDA 21 CFR 177.2600 compliant, oil & fat resistant | Bakery dough rollers, meat processing conveyor scrapers |
| Antistatic PU (ESD) | Surface resistivity 10โถ - 10โน ฮฉ/sq prevents sparking | Automated warehouse AGV wheels, paint-line rollers |
Important Engineering Guidance
The above properties are general characteristics. Final material selection depends on your specific application, operating conditions, load requirements, media compatibility, and service temperature. Please contact our polymer engineering team for tailored compounding guidance on PU Seals.
Production Batch Gallery
Actual production batch examples of PU Seals manufactured for OEM, automotive, railway, and heavy engineering clients. We manufacture standard catalogue sizes as well as bespoke custom geometries from your CAD models or physical samples.
Request an Engineering Quote
Share your required dimensions, polymer grade, or 2D/3D drawings for immediate engineering review and quote.