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    18 Products

    U-Cup Seals

    These U-cup seals create less friction than O-ring-loaded U-cups, so they wear more slowly. Also known as lip seals, U-cups have a sealing lip on both the inside and outside edges, so they can be used for rod and piston sealing. Pistons require two seals—install one facing in each direction.
    Note: Maximum performance values cannot be achieved simultaneously; for example, speed is affected by pressure, temperature, and other operating conditions.
    AN6226 U-Cup Seals
    Image of Product. Side 1. Front orientation. U-Cup Seals. Buna-N.
    Image of Product. Side 2. Back orientation. U-Cup Seals. Buna-N.
    Image of Product. Profile. Front orientation. CrossSection view. U-Cup Seals. Buna-N.

    Side 1

    Side 2

    Profile

    Image of Attribute. Rod Installation. Front orientation. Contains Annotated. Buna-N.
    Image of Attribute. Piston Installation. Front orientation. Contains Annotated. Buna-N.

    Rod Installation

    Piston Installation

    U-cups that meet military specification AN6226 fit dimensions specified by the standard.
    For Rod
    Sealing
    For Piston
    Sealing
    For Rod
    Dia.
    For Groove
    Dia.
    For Bore
    Dia.
    For Groove
    Dia.
    Max.
    Speed
    Max. Pressure,
    psi
    Temp. Range,
    ° F
    Hardness
    Color
    Pkg.
    Qty.
    Pkg.
    Buna-N
     
    For 0.282" Wide Grooves
    1/4"0.750"3/4"0.250"Not Rated120-20 to 212Durometer 70A (Hard)Black5000000000000
    3/8"0.875"7/8"0.375"Not Rated120-20 to 212Durometer 70A (Hard)Black500000000000
    1/2"1.000"1"0.500"Not Rated120-20 to 212Durometer 70A (Hard)Black500000000000
    5/8"1.125"1 1/8"0.625"Not Rated120-20 to 212Durometer 70A (Hard)Black500000000000
    3/4"1.250"1 1/4"0.750"Not Rated120-20 to 212Durometer 70A (Hard)Black500000000000
    7/8"1.375"1 3/8"0.875"Not Rated120-20 to 212Durometer 70A (Hard)Black500000000000
    1"1.500"1 1/2"1.000"Not Rated120-20 to 212Durometer 70A (Hard)Black500000000000
    1 1/8"1.625"1 5/8"1.125"Not Rated120-20 to 212Durometer 70A (Hard)Black500000000000
    1 1/4"1.750"1 3/4"1.250"Not Rated120-20 to 212Durometer 70A (Hard)Black500000000000
     
    For 0.344" Wide Grooves
    1 1/4"1.875"1 7/8"1.250"Not Rated120-20 to 212Durometer 70A (Hard)Black500000000000
    1 3/8"2.000"2"1.375"Not Rated120-20 to 212Durometer 70A (Hard)Black500000000000
    1 1/2"2.125"2 1/8"1.500"Not Rated120-20 to 212Durometer 70A (Hard)Black500000000000
    1 5/8"2.250"2 1/4"1.625"Not Rated120-20 to 212Durometer 70A (Hard)Black500000000000
    1 3/4"2.375"2 3/8"1.750"Not Rated120-20 to 212Durometer 70A (Hard)Black500000000000
    1 7/8"2.500"2 1/2"1.875"Not Rated120-20 to 212Durometer 70A (Hard)Black500000000000
    2"2.625"2 5/8"2.000"Not Rated120-20 to 212Durometer 70A (Hard)Black5000000000000
    2 1/4"2.875"2 7/8"2.250"Not Rated120-20 to 212Durometer 70A (Hard)Black5000000000000
    2 3/8"3.000"3"2.375"Not Rated120-20 to 212Durometer 70A (Hard)Black5000000000000
     
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