Product
Rod Seals
A rod seal sits in the cylinder head housing and seals against the reciprocating piston rod as it moves in and out — the seal most directly responsible for keeping hydraulic fluid inside the cylinder rather than leaking to atmosphere.
Rod seal profiles: BS, B3/UNR/UHR, BU, BD, OD, CH, FS, and R3 types.
Overview
How it works
The rod seal maintains continuous sealing contact with the rod's outside diameter across its full stroke, in both directions of travel and under working pressure — unlike a static seal, it must keep sealing while sliding, which is why rod-seal profiles are engineered for low friction and long wear life rather than maximum squeeze. A thin oil film is deliberately left on the rod as it extends, both lubricating the seal and preventing it from running dry.
Profiles
Available profiles
RS — Compact Rod Seal
Single-element compact profile for standard-duty hydraulic cylinders.
SPGO
Polyurethane rod seal with an integral dust-lip function in a single component.
CH — Step Seal
Two-piece PTFE/elastomer step-seal design for high-pressure, high-speed service.
Materials
Which compound, and why
Polyurethane (PU)
The default rod-seal material — high tensile strength and extrusion resistance under working pressure.
FKM (Viton)
High-temperature service or synthetic/aggressive hydraulic fluids beyond PU or NBR's range.
Applications
Where used
Fitted in the cylinder head of hydraulic cylinders across mobile equipment, industrial presses and machine tools — anywhere a piston rod reciprocates under pressure.