




High Pressure Silicone Seals for Hydraulic and Pneumatic Systems
- Model
- BH-seals
Item specifics
- Design
- Follow 3D Drawing Or Physical Object
- Process
- Molding
- Feature
- Extreme Pressure Sealing
- MOQ
- 100000pcs
- Application
- Hydraulic and Pneumatic Systems
Review
Description
High Pressure Silicone Seals for Hydraulic & Pneumatic Systems
Modern hydraulic and pneumatic systems demand absolute reliability under extreme pressure. Our high-performance silicone seals combine exceptional elasticity, thermal stability, and chemical resistance to withstand 10,000+ psi while maintaining a leak-free interface. Developed for linear and rotary motions, they outperform conventional elastomers in both dynamic and static applications.
Critical performance advantages
Material specifications & ratings
Standard silicone compound (HS70)
| Property | Test method | Value / range |
|---|---|---|
| Hardness (Shore A) | ASTM D2240 | 70 ± 5 |
| Tensile strength | ASTM D412 | ≥ 9.5 MPa |
| Elongation at break | ASTM D412 | 320% |
| Compression set (22h/175°C) | ASTM D395 B | ≤ 22% |
| Max. operating pressure | internal | 15,000 psi (dynamic with backup) |
System compatibility & dimensions
| Application type | Standard profile | Size range (inch/mm) |
|---|---|---|
| Hydraulic piston seals | U‑cup / step seal | 0.5″ – 20″ (12–500 mm) |
| Pneumatic rod wipers | double lip / scraper | 0.25″ – 12″ (6–300 mm) |
| Rotary shaft seals | spring‑energized | up to 8″ (200 mm) |
| Flange / static face | O‑ring / custom molded | any custom size |
Why silicone for extreme hydraulics?
While traditional NBR or FKM seals handle many fluids, high-pressure silicone offers unique advantages: flexibility at low temperatures that prevents brittle fracture, excellent resistance to compression set after repeated pressurisation, and compliance with FDA/NSF where incidental fluid contact occurs. Our proprietary high-modulus silicone compounds are reinforced with nano-silica to resist extrusion even with large clearances.
In pneumatic systems, the lack of lubricating oil can cause rapid wear. Our low-friction silicone blends incorporate permanent lubricants, reducing breakout friction by up to 40% compared to standard nitrile. This guarantees smooth actuation in critical control valves and cylinders.
Custom design & extrusion profiles
Our engineering team supports custom profiles, backup ring integration, and composite seals with bonded PTFE. Finite element analysis (FEA) available for high-pressure validation.
Extreme pressure sealing profile
(illustrative cross-section)
- hydraulic cylinders
- pneumatic valves
- rotary actuators
- subsea accumulators
Pressure – temperature matrix (selection guide)
| Compound grade | Max static pressure | Max temp | Typical application |
|---|---|---|---|
| HS70‑U (universal) | 12,000 psi | 200°C | general hydraulics |
| HS80‑HP (high modulus) | 18,000 psi* | 230°C | extreme pressure / shock |
| LTS‑60 (low temp) | 10,000 psi | 150°C | arctic pneumatic |
| FR‑sil (flame retard) | 8,500 psi | 220°C | mining / steel mills |
*with anti‑extrusion backup rings. All values based on 0.5 mm radial gap.









