The UPH-Type Piston Rod Seal represents a specialized Universal Pressure-Hardened sealing solution designed for applications requiring superior performance under high-pressure conditions with moderate reciprocating speeds. This variant features an optimized asymmetrical lip geometry that provides progressive pressure response while maintaining exceptional sealing integrity.
Asymmetrical Dual-Function Lip – Combines a primary high-pressure sealing edge with secondary guiding/stabilizing geometry
Pressure-Reinforced Profile – Internally structured to prevent material extrusion under sustained high pressure
Monolithic Construction – Single-material engineering-grade polyurethane with controlled hardness gradient
Anti-Extrusion Design – Built-in geometric features that provide extrusion resistance without separate anti-extrusion rings
High-Pressure Endurance – Maintains sealing integrity up to 40 MPa (400 bar) continuous operation
Low-Friction Operation – Optimized contact geometry reduces breakout friction by approximately 25% compared to conventional high-pressure seals
Zero-Leakage Performance – Achieves virtually leakage-free operation across pressure cycles
Durability – Exceptional wear resistance with service life up to 3,000 km of rod travel under optimal conditions
Installation Simplicity – Single-component design eliminates complex assembly sequences
| Parameter | Specification Range |
|---|---|
| Operating Pressure | 0.5 – 40 MPa |
| Temperature Range | -35°C to +110°C |
| Surface Speed | ≤ 0.8 m/s |
| Rod Hardness | ≥ 45 HRC recommended |
| Surface Finish | Ra 0.05 – 0.2 μm optimal |
| Media Compatibility | Hydraulic oils (mineral, synthetic), water-glycol, HFA/HFB fluids |
High-Pressure Hydraulic Systems – Plastic injection molding machines, die casting equipment
Industrial Presses – Hydraulic punching, stamping, and forming presses
Marine Hydraulics – Steering systems, hatch controls, deck machinery
Energy Sector – Hydraulic components for wind turbines, power generation equipment
Mobile Machinery – Advanced construction equipment, crane hydraulic systems
Gland Preparation – Precision-machined glands with chamfered edges (typically 15-20°)
Surface Compatibility – Hard-chromed or nitrided rods with surface hardness ≥ 800 HV
Clearance Control – Radial clearance ≤ 0.1 mm recommended for 40 MPa applications
Initial Lubrication – System fluid application during installation mandatory
Leakage Rate < 0.05 ml/cycle at 25 MPa test pressure
Breakout Friction < 15% of theoretical piston force
Wear Rate < 0.01 mm per 1,000 km of rod travel
Pressure Cycling Endurance: ≥ 1,000,000 cycles at 25 MPa
Secondary Scrapers – For applications with significant environmental contamination
Guide/Bearing Elements – To accommodate side loads in long-stroke applications
Buffer Seals – For systems with extreme pressure spikes above 50 MPa
Rod Surface Treatments – Advanced coatings (CrN, DLC) for extended service life
Inspection Interval – Recommended every 2,000 operating hours
Replacement Indicators – Visible lip deformation > 0.2 mm, increased leakage, significant friction increase
Failure Prevention – Proper filtration (≤ 10 μm), contamination control, temperature monitoring
The UPH-type distinguishes itself through:
Pressure-Adaptive Geometry – Lip profile that expands proportionally to system pressure
Material Homogeneity – Consistent material properties throughout cross-section
Versatile Installation – Suitable for both hydraulic and moderate-speed pneumatic applications
Retrofit Capability – Direct replacement for many conventional high-pressure seals without gland modification
Engineering Note: UPH-type seals represent a balanced solution between extreme high-pressure capability and operational practicality. For ultra-high pressure (>50 MPa) or high-speed (>1.2 m/s) applications, consult specialized seal variants. All specifications should be verified against manufacturer data sheets for specific operating conditions.
Original text from: pneumatic seal https://www.bszzseal.com/
