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    198 Products

    O-Ring-Loaded U-Cup Seals

    Image of Product. Side 1. Front orientation. U-Cup Seals. O-Ring-Loaded U-Cup Seals, Polyurethane Rubber.
    Image of Product. Side 2. Back orientation. U-Cup Seals. O-Ring-Loaded U-Cup Seals, Polyurethane Rubber.
    Image of Product. Profile. Front orientation. CrossSection view. U-Cup Seals. O-Ring-Loaded U-Cup Seals, Polyurethane Rubber.

    Side 1

    Side 2

    Profile

    Image of Attribute. Rod Installation. Front orientation. Contains Annotated. O-Ring-Loaded U-Cup Seals, Polyurethane Rubber.
    Image of Attribute. Piston Installation. Front orientation. Contains Annotated. O-Ring-Loaded U-Cup Seals, Polyurethane Rubber.

    Rod Installation

    Piston Installation

    Also known as loaded-lip seals and PolyPaks, an O-ring secures these U-cups to the rod or piston for better sealing performance at lower pressures than unsupported U-cup seals. Because U-cups have a sealing lip on both the inside and outside edges, 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.
    For Rod
    Sealing
    For Piston
    Sealing
    O-Ring
    For Rod
    Dia.
    For Groove
    Dia.
    For Bore
    Dia.
    For Groove
    Dia.
    Max. Speed,
    ft/sec
    Max. Pressure,
    psi
    Temp. Range,
    ° F
    Hardness
    Color
    Hardness
    Color
    Each
    Polyurethane Rubber with Buna-N O-Ring
     
    For 0.138" Wide Grooves
    1/8"0.375"3/8"0.125"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    3/16"0.438"7/16"0.187"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1/4"0.500"1/2"0.250"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    5/16"0.563"9/16"0.312"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    3/8"0.625"5/8"0.375"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    7/16"0.688"11/16"0.437"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1/2"0.750"3/4"0.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    5/8"0.875"7/8"0.625"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    3/4"1.000"1"0.750"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    7/8"1.125"1 1/16"0.875"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1"1.250"1 1/4"1.000"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1 1/8"1.375"1 3/8"1.125"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1 1/4"1.500"1 1/2"1.250"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
     
    For 0.172" Wide Grooves
    3/4"1.063"1 1/16"0.750"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1"1.313"1 5/16"1.000"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1 3/16"1.500"1 1/2"1.187"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1 3/8"1.688"1 11/16"1.375"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
     
    For 0.206" Wide Grooves
    3/16"0.563"9/16"0.187"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    3/8"0.750"3/4"0.375"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    7/16"0.813"13/16"0.437"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1/2"0.875"7/8"0.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    5/8"1.000"1"0.625"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    3/4"1.125"1 1/8"0.750"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    7/8"1.250"1 1/4"0.875"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1"1.375"1 3/8"1.000"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1 1/8"1.500"1 1/2"1.125"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1 3/16"1.563"1 9/16"1.187"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1 1/4"1.625"1 5/8"1.250"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1 3/8"1.750"1 3/4"1.375"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1 1/2"1.875"1 7/8"1.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1 5/8"2.000"2"1.625"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1 7/8"2.250"2 1/4"1.875"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    2"2.375"2 3/8"2.000"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    2 1/8"2.500"2 1/2"2.125"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    2 3/8"2.750"2 3/4"2.375"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    2 1/2"2.875"2 7/8"2.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    2 5/8"3.000"3"2.625"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    2 3/4"3.125"3 1/8"2.750"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
     
    For 0.275" Wide Grooves
    1/2"1.000"1"0.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    5/8"1.125"1 1/8"0.625"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    3/4"1.250"1 1/4"0.750"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    7/8"1.375"1 3/8"0.875"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1"1.500"1 1/2"1.000"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1 1/8"1.625"1 5/8"1.125"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1 3/16"1.688"1 11/16"1.187"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1 1/4"1.750"1 3/4"1.250"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1 3/8"1.875"1 7/8"1.375"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1 1/2"2.000"2"1.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    1 3/4"2.250"2 1/4"1.750"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    2"2.500"2 1/2"2.000"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    2 1/4"2.750"2 3/4"2.250"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black00000000000
    2 1/2"3.000"3"2.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    2 3/4"3.250"3 1/4"2.750"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    3"3.500"3 1/2"3.000"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    3 1/2"4.000"4"3.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    3 3/4"4.250"4 1/4"3.750"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    4"4.500"4 1/2"4.000"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    4 1/2"5.000"5"4.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    4 3/4"5.250"5 1/4"4.750"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    6 1/2"7.000"7"5.000"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
     
    For 0.343" Wide Grooves
    1 3/8"2.000"2"1.375"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1 7/8"2.500"2 1/2"1.875"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    2"2.625"2 5/8"2.000"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    2 3/8"3.000"3"2.375"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    5 3/8"6.000"6"5.375"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    7 3/8"8.000"8"7.375"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
     
    For 0.413" Wide Grooves
    1 1/4"2.000"2"1.250"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    1 1/2"2.250"2 1/4"1.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    1 5/8"2.375"2 3/8"1.625"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    1 3/4"2.500"2 1/2"1.750"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    2"2.750"2 3/4"2.000"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    2 1/8"2.875"2 7/8"2.125"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    2 1/4"3.000"3"2.250"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    2 1/2"3.250"3 1/4"2.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    2 3/4"3.500"3 1/2"2.750"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    3"3.750"3 3/4"3.000"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    3 1/4"4.000"4"3.250"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    3 1/2"4.250"4 1/4"3.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    3 3/4"4.500"4 1/2"3.750"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    4 3/4"5.500"5 1/2"4.750"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
     

    High-Stability O-Ring-Loaded U-Cup Seals

    Image of Product. Side 1. Front orientation. U-Cup Seals. High-Stability O-Ring-Loaded U-Cup Seals, Polyurethane Rubber.
    Image of Product. Side 2. Back orientation. U-Cup Seals. High-Stability O-Ring-Loaded U-Cup Seals, Polyurethane Rubber.
    Image of Product. Profile. Front orientation. CrossSection view. U-Cup Seals. High-Stability O-Ring-Loaded U-Cup Seals, Polyurethane Rubber.

    Side 1

    Side 2

    Profile

    Image of Attribute. Rod Installation. Front orientation. Contains Annotated. High-Stability O-Ring-Loaded U-Cup Seals, Polyurethane Rubber.
    Image of Attribute. Piston Installation. Front orientation. Contains Annotated. High-Stability O-Ring-Loaded U-Cup Seals, Polyurethane Rubber.

    Rod Installation

    Piston Installation

    Also known as Type B seals, loaded-lip seals, and PolyPaks, these U-cups are wider than our other O-ring-loaded U-cup seals for better stability. An O-ring secures them to the rod or piston, preventing leaks at low pressure and as the seal wears. Because U-cups have a sealing lip on both the inside and outside edges, 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.
    For Rod
    Sealing
    For Piston
    Sealing
    O-Ring
    For Rod
    Dia.
    For Groove
    Dia.
    For Bore
    Dia.
    For Groove
    Dia.
    Max. Speed,
    ft/sec
    Max. Pressure,
    psi
    Temp. Range,
    ° F
    Hardness
    Color
    Hardness
    Color
    Each
    Polyurethane Rubber with Buna-N O-Ring
     
    For 0.206" Wide Grooves
    5/8"0.875"7/8"0.625"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    3/4"1.000"1"0.750"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1"1.250"1 1/4"1.000"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1 1/4"1.500"1 1/2"1.250"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
     
    For 0.253" Wide Grooves
    1 3/4"2.125"2 1/8"1.750"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
     
    For 0.275" Wide Grooves
    1/4"0.500"1/2"0.250"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    3/8"0.625"5/8"0.375"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1/2"0.750"3/4"0.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    5/8"0.875"7/8"0.625"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    3/4"1.000"1"0.750"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    7/8"1.125"1 1/8"0.875"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1"1.250"1 1/4"1.000"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1 1/16"1.313"1 5/16"1.062"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1 1/8"1.375"1 3/8"1.125"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1 1/4"1.500"1 1/2"1.250"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1 1/4"1.625"1 5/8"1.250"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1 3/8"1.625"1 5/8"1.375"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1 1/2"1.750"1 3/4"1.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    2"2.250"2 1/4"2.000"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    2 1/8"2.375"2 3/8"2.125"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
     
    For 0.343" Wide Grooves
    7/8"1.250"1 1/4"0.875"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1"1.375"1 3/8"1.000"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1 3/8"1.750"1 3/4"1.375"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1 1/2"1.875"1 7/8"1.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1 5/8"2.000"2"1.625"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1 3/4"2.125"2 1/8"1.750"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    2"2.375"2 3/8"2.000"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
     
    For 0.413" Wide Grooves
    1"1.500"1 1/2"1.000"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1 1/4"1.750"1 3/4"1.250"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1 3/8"1.750"1 3/4"1.375"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1 1/2"1.875"1 7/8"1.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1 1/2"2.000"2"1.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1 5/8"2.000"2"1.625"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    1 3/4"2.250"2 1/4"1.750"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    2"2.500"2 1/2"2.000"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black000000000000
    2 3/8"2.875"2 7/8"2.375"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    2 1/2"2.875"2 7/8"2.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    2 1/2"3.000"3"2.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    2 3/4"3.250"3 1/4"2.750"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    3 1/2"4.000"4"3.500"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
    3 5/8"4.125"4 1/8"3.625"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
     
    For 0.550" Wide Grooves
    3 3/8"4.000"4"3.375"1.65,000-65 to 300Durometer 90A (Hard)BlackDurometer 70A (Medium)Black0000000000000
     

    High-Pressure U-Cup Seals

    Image of Product. Side 1. Front orientation. U-Cup Seals. High-Pressure U-Cup Seals, Leather.
    Image of Product. Side 2. Back orientation. U-Cup Seals. High-Pressure U-Cup Seals, Leather.
    Image of Product. Profile. Front orientation. CrossSection view. U-Cup Seals. High-Pressure U-Cup Seals, Leather.

    Side 1

    Side 2

    Profile

    Image of Attribute. Rod Installation. Front orientation. Contains Annotated. High-Pressure U-Cup Seals, Leather.
    Image of Attribute. Piston Installation. Front orientation. Contains Annotated. High-Pressure U-Cup Seals, Leather.

    Rod Installation

    Piston Installation

    Rated for pressure up to 10,000 psi, these leather U-cups handle over 80 times more pressure than our Buna-N U-cups. Leather is tough, pliable, and wear resistant, so it flexes to fit uneven surfaces and fill voids. U-cups 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.
    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
    Color
    Each
    Wax-Filled Leather
     
    For 0.250" Wide Grooves
    1/4"0.750"3/4"0.250"Not Rated10,0000 to 180Black0000000000000
    3/8"0.875"7/8"0.375"Not Rated10,0000 to 180Black000000000000
    1/2"1.000"1"0.500"Not Rated10,0000 to 180Black000000000000
    5/8"1.125"1 1/8"0.625"Not Rated10,0000 to 180Black000000000000
    3/4"1.250"1 1/4"0.750"Not Rated10,0000 to 180Black000000000000
    7/8"1.375"1 3/8"0.875"Not Rated10,0000 to 180Black000000000000
    1"1.500"1 1/2"1.000"Not Rated10,0000 to 180Black000000000000
    1 1/8"1.625"1 5/8"1.125"Not Rated10,0000 to 180Black000000000000
    1 1/4"1.750"1 3/4"1.250"Not Rated10,0000 to 180Black000000000000
     

    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.
    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

    For Rod
    Sealing
    For Piston
    Sealing
    For Rod
    Dia.
    For Groove
    Dia.
    For Bore
    Dia.
    For Groove
    Dia.
    Max. Speed,
    ft/sec
    Max. Pressure,
    psi
    Temp. Range,
    ° F
    Hardness
    Color
    Each
    Buna-N
     
    For 0.093" Wide Grooves
    1/4"0.375"3/8"0.250"1.6250-40 to 250Durometer 80A (Hard)Black0000000000000
    5/8"0.812"13/16"0.625"1120-20 to 212Durometer 70A (Hard)Black00000000000
     
    For 0.125" Wide Grooves
    1/4"0.437"7/16"0.250"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    1/2"0.750"3/4"0.500"1120-20 to 212Durometer 70A (Hard)Black00000000000
    5/8"0.812"13/16"0.625"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    3/4"1.000"1"0.750"1120-20 to 212Durometer 70A (Hard)Black00000000000
    7/8"1.125"1 1/8"0.875"1120-20 to 212Durometer 70A (Hard)Black00000000000
    1"1.250"1 1/4"1.000"1120-20 to 212Durometer 70A (Hard)Black00000000000
    1 1/4"1.500"1 1/2"1.250"1120-20 to 212Durometer 70A (Hard)Black00000000000
     
    For 0.156" Wide Grooves
    1/4"0.562"9/16"0.250"1120-20 to 212Durometer 70A (Hard)Black00000000000
    3/8"0.625"5/8"0.375"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    1/2"0.750"3/4"0.500"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    5/8"0.875"7/8"0.625"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    3/4"1.000"1"0.750"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    7/8"1.125"1 1/8"0.875"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    1"1.250"1 1/4"1.000"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    1 1/8"1.375"1 3/8"1.125"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    1 1/4"1.500"1 1/2"1.250"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    1 3/8"1.687"1 11/16"1.375"1120-20 to 212Durometer 70A (Hard)Black00000000000
    1 1/2"1.812"1 13/16"1.500"1120-20 to 212Durometer 70A (Hard)Black00000000000
    1 3/4"2.000"2"1.750"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
     
    For 0.188" Wide Grooves
    7/8"1.250"1 1/4"0.875"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    1"1.312"1 5/16"1.000"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    1 1/8"1.437"1 7/16"1.125"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    1 1/4"1.562"1 9/16"1.250"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    1 3/8"1.687"1 11/16"1.375"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    1 1/2"1.812"1 13/16"1.500"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    1 3/4"2.125"2 1/8"1.750"1120-20 to 212Durometer 70A (Hard)Black00000000000
    2"2.375"2 3/8"2.000"1120-20 to 212Durometer 70A (Hard)Black00000000000
     
    For 0.218" Wide Grooves
    3/4"1.125"1 1/8"0.750"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    1 3/8"1.750"1 3/4"1.375"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    1 1/2"1.875"1 7/8"1.500"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    1 5/8"2.000"2"1.625"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    1 3/4"2.125"2 1/8"1.750"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    1 7/8"2.250"2 1/4"1.875"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    2"2.375"2 3/8"2.000"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
    2 1/4"2.625"2 5/8"2.250"1.6250-40 to 250Durometer 80A (Hard)Black0000000000000
    2 1/2"2.875"2 7/8"2.500"1.6250-40 to 250Durometer 80A (Hard)Black0000000000000
    2 3/4"3.125"3 1/8"2.750"1.6250-40 to 250Durometer 80A (Hard)Black0000000000000
    3"3.375"3 3/8"3.000"1.6250-40 to 250Durometer 80A (Hard)Black0000000000000
     
    For 0.250" Wide Grooves
    1 3/8"1.875"1 7/8"1.375"1120-20 to 212Durometer 70A (Hard)Black00000000000
    1 1/2"2.000"2"1.500"1120-20 to 212Durometer 70A (Hard)Black00000000000
    1 3/4"2.250"2 1/4"1.750"1120-20 to 212Durometer 70A (Hard)Black00000000000
    2"2.500"2 1/2"2.000"1120-20 to 212Durometer 70A (Hard)Black00000000000
    2 1/2"2.937"2 15/16"2.500"1.6250-40 to 250Durometer 80A (Hard)Black0000000000000
    2 3/4"3.187"3 3/16"2.750"1.6250-40 to 250Durometer 80A (Hard)Black0000000000000
    3"3.437"3 7/16"3.000"1.6250-40 to 250Durometer 80A (Hard)Black0000000000000
     
    For 0.281" Wide Grooves
    2 1/2"3.000"3"2.500"1.6250-40 to 250Durometer 80A (Hard)Black000000000000
     
    For 0.406" Wide Grooves
    2 1/4"3.000"3"2.250"1.6250-40 to 250Durometer 80A (Hard)Black0000000000000
     
    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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