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    44 Products

    Extension Springs

    The farther you stretch these springs, the harder they pull to bring the two ends back together. They're commonly used to tension cable, return an air cylinder to its starting point, or hold a door closed.
    Double-Loop End—Ends are strengthened by an extra loop, so these springs are less likely to break if overstretched.
    Straight-Wire End—Bend the long, straight ends into custom loops and hooks.
    Spring Steel—Strong and resilient, but best suited for dry environments since moisture will cause these springs to rust.
    Corrosion-Resistant 302 Stainless Steel—Won’t corrode from exposure to moisture and mild chemicals, including ammonia often found in cleaning solutions. These springs are easier to extend than steel, but can’t handle as high a load.
    Minimum Load—The amount of force required to start extending the spring.
    Maximum Load—The amount of force required to fully extend the spring.
    Load,
    lb.
    Lg.
    OD
    Wire
    Dia.
    Extended Lg.
    @ Max. Load
    Min.
    Max.
    Spring Rate,
    lbf/in
    Pkg.
    Qty.
    Pkg.
    Double-Loop End
    Image of Product. Front orientation. Contains Border, MultipleImages. Extension Springs. Double-Loop End.
     
    Spring Steel
    2"0.375"0.047"2.951"2.229.427.57200000000000000
    2"0.375"0.048"2.97"2.099.427.573000000000000
    3"0.375"0.048"4.73"2.099.424.253000000000000
    3 1/2"0.75"0.092"8.49"7.1931.1815.343000000000000
    4"0.375"0.047"6.425"2.229.422.9720000000000000
    4"0.375"0.048"6.47"2.099.422.973000000000000
    4"0.625"0.072"6.627"5.121.16.0920000000000000
    4"0.75"0.093"5.78"8.7531.1812.620000000000000
    6"0.25"0.032"10.47"0.934.550.813000000000000
    6"0.375"0.048"11.47"2.099.421.343000000000000
    6 1/4"0.75"0.08"8.25"4.511.13.31000000000000
    8"0.5"0.063"13.31"3.5215.582.273000000000000
    8"0.625"0.072"14.26"3.96192.43000000000000
    8"0.625"0.072"14.667"5.121.12.420000000000000
    10"0.5"0.063"16.599"3.8415.581.7820000000000000
    10"0.5"0.063"16.78"3.5215.581.783000000000000
    10"0.625"0.072"18.649"5.121.11.8520000000000000
    12"0.5"0.063"20.046"3.8415.581.4620000000000000
    12"0.625"0.072"21.89"3.96191.523000000000000
    12"0.625"0.072"22.526"5.121.11.5220000000000000
    15 3/4"1.125"0.105"17.79"6.018.451.2210000000000000
    15 7/8"0.375"0.054"16.89"3.654.951.310000000000000
    16"0.296"0.041"17"22.640.641000000000000
    16"0.344"0.047"18"1.993.670.8410000000000000
    16"0.421"0.062"17"4.76.92.210000000000000
     
    Corrosion-Resistant 302 Stainless Steel
    2"0.25"0.032"3.231"0.94.042.552000000000000
    2"0.375"0.047"2.951"1.897.55.92000000000000
    3"0.25"0.032"4.986"0.94.011.572000000000000
    3"0.375"0.047"4.695"1.887.673.422000000000000
    3 1/2"0.75"0.093"4.962"7.4427.3513.622000000000000
    4"0.375"0.047"6.425"1.887.722.412000000000000
    4"0.75"0.093"5.78"7.4327.2711.142000000000000
    5"0.25"0.032"8.603"0.94.080.882000000000000
    5"0.375"0.047"8.914"1.889.151.862000000000000
    5"0.75"0.093"7.543"7.4328.228.172000000000000
    6"0.25"0.032"10.315"0.94.030.732000000000000
    6"0.5"0.063"9.592"3.2613.592.882000000000000
    6"0.75"0.093"8.962"7.4426.556.452000000000000
    8"0.5"0.063"13.175"3.2613.992.072000000000000
    8"0.625"0.072"14.667"4.3318.062.062000000000000
    10"0.5"0.063"16.599"3.2613.961.622000000000000
    10"0.625"0.072"18.649"4.3318.161.62000000000000
    12"0.5"0.063"20.046"3.2613.971.332000000000000
     
    Straight-Wire with Double-Loop End × Straight-Wire End
    Image of Product. Front orientation. Extension Springs. Straight-Wire with Double-Loop End × Straight-Wire End.
     
    Spring Steel
    11 1/2"0.406"0.041"15.5"0.871.610000000000000
     
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