The OUY hydraulic piston seal is a dual-layer tightening cylinder seal designed specifically for excavator hydraulic cylinders and tensioning cylinder applications. It features a nitrile rubber (NBR) outer layer for flexibility and oil resistance, combined with a durable plastic inner layer that enhances pressure distribution and durability. This design provides excellent wear resistance, high pressure capability, and long service life, making it widely used in construction machinery such as excavators, forklifts, and loaders.
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Product Overview
The OUY seal is a high-performance hydraulic piston seal primarily used for tensioning cylinders of construction machinery. Its dual-layer construction combines the flexibility of nitrile rubber with the rigidity of a plastic inner ring, creating a sealing solution that withstands demanding operating conditions in excavators, forklifts, and other heavy equipment.
The seal’s flat cylindrical profile ensures optimal sealing efficiency, preventing hydraulic fluid leakage while maintaining stable pressure in high-pressure environments.
How It Works
The OUY seal operates by forming a tight, flexible barrier between moving parts of hydraulic equipment. The outer NBR layer provides oil resistance and adapts to pressure changes, while the rigid inner layer ensures even pressure distribution and prevents deformation under high loads. When hydraulic pressure increases, the seal’s elastic material adapts to create a leak-proof interface, blocking external contaminants while retaining hydraulic fluid.
Specifications and Parameters
| Parameter |
Specification |
| Product Name |
OUY Hydraulic Piston Seal |
| Type |
Dual-layer tightening cylinder seal |
| Outer Material |
NBR (Nitrile Butadiene Rubber) |
| Inner Material |
Plastic / Nylon |
| Construction |
Dual-layer (flexible outer + rigid inner) |
| Pressure Rating |
Up to 30-45 MPa / 5000 PSI |
| Temperature Range |
-40°C to +120°C |
| Color |
Black (NBR outer), White/Inner (plastic layer) |
| Application |
Piston seal for excavator cylinders, forklifts, loaders |
Product Features
1. Dual-Layer Construction
Combines NBR rubber (flexibility, oil resistance) with a rigid plastic inner layer (pressure distribution, durability) for superior sealing performance.
2. High Pressure Capability
Withstands pressures up to 5000 PSI (approx. 35 MPa) and ensures reliable sealing in high-pressure hydraulic systems.
3. Excellent Wear Resistance
Engineered to resist wear and corrosion, providing long service life even in harsh industrial environments. Field data suggests up to 30-40% longer lifespan than single-layer seals.
4. Wide Temperature Range
Operates reliably from -40°C to +120°C, suitable for various climate conditions.
5. Versatile Compatibility
Compatible with standard hydraulic systems and fits multiple excavator models, including brands like Volvo, Caterpillar, Komatsu, and Doosan.
6. Effective Contamination Exclusion
Functions as both a piston seal and a dust-proof component, protecting key mechanical parts from dust and debris.
Need OUY hydraulic piston seals for your excavator or construction equipment?
Contact SANPING SEAL today with your size requirements. Our team will provide a free quote within 24 hours.