The HBY buffer seal is a combination rod buffer seal consisting of a high-performance PU sealing element and a rigid anti-extrusion backup ring . It is designed to be used in conjunction with the main rod seal to absorb impact and surge pressure under heavy loads, isolate high-temperature fluids, and improve the overall service life of the sealing system .
SANPING SEAL – Engineering Machinery High-End Seals – 17 Years Export Expertise
Product Overview
The HBY buffer seal is an essential component in hydraulic cylinder sealing systems. Its primary function is to protect the main rod seal from pressure spikes and high-temperature fluids . The combination design features a soft polyurethane sealing element paired with a rigid backup ring (POM or PA) that provides excellent extrusion resistance .
How It Works
The HBY operates through a dual-component mechanism :
The PU sealing element provides primary sealing contact with the rod, absorbing shock pressure and releasing backpressure through specially designed relief grooves on the outer lip
The rigid backup ring (POM or PA) prevents seal extrusion under high pressure and provides impact resistance
The relief groove design allows backpressure to dissipate, preventing damage to the main seal from pressure buildup between the buffer and the primary rod seal .
Specifications and Parameters
| Parameter |
Detail |
| Product Name |
HBY Buffer Seal / Buffer Ring |
| Type |
Combination rod buffer seal (PU + Backup Ring) |
| Sealing Element Material |
PU (Polyurethane) |
| Backup Ring Material |
POM (Polyoxymethylene) / PA (Nylon) |
| Hardness (PU) |
93 ± 2 Shore A |
| Color |
Grey, Black, Blue, Yellow |
| Working Pressure |
≤ 40 MPa |
| Temperature Range |
-35°C to +110°C |
| Working Speed |
≤ 1 m/s |
| Medium |
Mineral oil-based hydraulic oils |
| Application |
Rod buffer seal for hydraulic cylinders |
Product Features
1. Excellent Shock Absorption
The HBY absorbs impact and surge pressure under heavy loads, protecting the main rod seal from pressure spikes .
2. Backpressure Relief
The specially designed relief grooves on the outer lip allow backpressure to dissipate, preventing damage to the main seal .
3. Anti-Extrusion Protection
The rigid backup ring (POM/PA) provides excellent extrusion resistance, allowing the seal to perform in demanding conditions .
4. Low Compression Set
The high-performance PU material maintains its shape even after long-term compression, ensuring consistent sealing performance .
5. Good Wear Resistance
PU material provides excellent abrasion resistance and impact resistance for demanding applications .
6. Easy Installation
The compact design allows for straightforward installation without special tools .
7. Temperature & Fluid Compatibility
Operates from -35°C to +110°C and is compatible with mineral oil-based hydraulic oils .
Need HBY buffer seals for your hydraulic cylinder application?
Contact SANPING SEAL today with your rod size requirements. Our team will provide a free quote within 24 hours.
