1.Performance and Purpose
    Comprising a wear-resistant ring filled with PTFE and O-shape rubber washer, with the latter providing pre-tightening force to compensate for the wear and t-ear of the PTFE square ring. It is applicable for sealing the piston of hydraulic cylinder, which is two way sealing. It is generally used together with guide rin-gs. For diameters less than ?40, detachable grooves shall be used.
2.Materials
    PTFE + NBR. In special circumstances FKM is used for rubber elastomer.
3.Working conditions
    Working pressure：0-40MPa；
    Reciprocated speed：≤5m/s；
    Working temperature：If O-ring is made of NBR：-30～+120℃，if it is made of FKM：-20～+200℃；
    Working medium：hydraulic oil, gas, water (for phosphate-based hydraulic oil, please use FKM.)
4.Design standard
    The series is in conformity with ISO 7425/I, GB/T15242.1-94 and GB/T15242.3-94. Reference can also be made to Shaban’s GS55044 series, Merkel’s OMK-MR and Parker’s OE series.
5.Labeling Method
    The hole-use square rings are labeled with Order No. (Please see the rear.)