Hydraulic cylinders depend on a set of seals working together. Choosing them correctly prevents leakage, contamination and premature wear.
The main seals in a cylinder
- Rod seal — stops fluid leaking out along the rod.
- Piston seal — separates pressure on both sides of the piston.
- Wiper / dust seal — keeps dirt out as the rod retracts.
- Static seals and O-rings — seal end caps and ports.
Checklist before you order
- Operating pressure — higher pressure needs harder compounds or support rings.
- Temperature — NBR suits most hydraulic oils; Viton for higher heat.
- Fluid type — mineral oil, water-glycol or synthetic fluids each need compatible compounds.
- Speed and stroke — fast movement generates heat and wear.
- Environment — dusty or outdoor machines need effective wipers.
When replacing seals, also inspect the rod and bore surfaces. A scratched rod will damage new seals quickly.
Replacement seals from samples
For older or imported machines, original seals can be hard to find. Share a sample or the groove dimensions and we can develop matching seals in the right compound.
