SPGA type bidirectional piston seal is a compact double-acting hydraulic piston seal, commonly called Glyd ring. It consists of a filled PTFE sliding seal ring and an elastic energizer made of NBR or FKM. The elastomer energizer supplies constant preload, pressing the PTFE sealing surface firmly against the cylinder bore. It prevents hydraulic fluid bypass across the piston and achieves reliable bidirectional sealing for double-acting hydraulic cylinders.
The PTFE sliding ring features ultra-low friction coefficient and anti stick-slip property, effectively avoiding crawling under low-speed reciprocating motion. With outstanding wear resistance and chemical inertness, the SPGA piston seal can handle working pressure up to 35 MPa. Its operating temperature covers -30℃ to 160℃, subject to the material of the internal energizer. It works smoothly at reciprocating speed up to 1.5 m/s under repeated cyclic operations.
Compatible with mineral hydraulic oil and most conventional hydraulic fluids, SPGA compact piston seals are widely used in excavators, injection molding machines, hydraulic presses and other engineering machinery cylinders. It matches standard piston groove sizes for easy installation and direct replacement. With compact structure, minimal fluid leakage and extended service life, the SPGA bidirectional piston seal serves as a high-performance sealing option for heavy-duty double-acting hydraulic systems.
Original text from: Hydraulic and Pneumatic Seals https://www.bszzseal.com/
