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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.
    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"2.229.427.5721330K502000000
    2"0.375"0.048"2.97"2.099.427.5731330K6200000
    3"0.375"0.048"4.73"2.099.424.2531330K6400000
    3 1/2"0.75"0.092"8.49"7.1931.1815.3431330K6500000
    4"0.375"0.047"6.425"2.229.422.9721330K50700000
    4"0.375"0.048"6.47"2.099.422.9731330K8800000
    4"0.625"0.072"6.627"5.121.16.0921330K50900000
    4"0.75"0.093"5.78"8.7531.1812.621330K51100000
    6"0.25"0.032"10.47"0.934.550.8131330K7600000
    6"0.375"0.048"11.47"2.099.421.3431330K7700000
    6 1/4"0.75"0.08"8.25"4.511.13.311330K3300000
    8"0.5"0.063"13.31"3.5215.582.2731330K8200000
    8"0.625"0.072"14.26"3.96192.431330K8300000
    8"0.625"0.072"14.667"5.121.12.421330K52300000
    10"0.5"0.063"16.599"3.8415.581.7821330K52400000
    10"0.5"0.063"16.78"3.5215.581.7831330K8400000
    10"0.625"0.072"18.649"5.121.11.8521330K52500000
    12"0.5"0.063"20.046"3.8415.581.4621330K52600000
    12"0.625"0.072"21.89"3.96191.5231330K8700000
    12"0.625"0.072"22.526"5.121.11.5221330K52700000
    15 3/4"1.125"0.105"17.79"6.018.451.2211330K12100000
    15 7/8"0.375"0.054"16.89"3.654.951.311330K12400000
    16"0.296"0.041"17"22.640.6411330K1220000
    16"0.344"0.047"18"1.993.670.8411330K12300000
    16"0.421"0.062"17"4.76.92.211330K12500000
     
    Corrosion-Resistant 302 Stainless Steel
    2"0.25"0.032"3.231"0.94.042.5523795N1100000
    2"0.375"0.047"2.951"1.897.55.923795N1600000
    3"0.25"0.032"4.986"0.94.011.5723795N1200000
    3"0.375"0.047"4.695"1.887.673.4223795N1700000
    3 1/2"0.75"0.093"4.962"7.4427.3513.6223795N3300000
    4"0.375"0.047"6.425"1.887.722.4123795N1800000
    4"0.75"0.093"5.78"7.4327.2711.1423795N3400000
    5"0.25"0.032"8.603"0.94.080.8823795N1400000
    5"0.375"0.047"8.914"1.889.151.8623795N1900000
    5"0.75"0.093"7.543"7.4328.228.1723795N3600000
    6"0.25"0.032"10.315"0.94.030.7323795N1500000
    6"0.5"0.063"9.592"3.2613.592.8823795N2300000
    6"0.75"0.093"8.962"7.4426.556.4523795N3700000
    8"0.5"0.063"13.175"3.2613.992.0723795N2400000
    8"0.625"0.072"14.667"4.3318.062.0623795N2900000
    10"0.5"0.063"16.599"3.2613.961.6223795N2500000
    10"0.625"0.072"18.649"4.3318.161.623795N3100000
    12"0.5"0.063"20.046"3.2613.971.3323795N2600000
     
    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"0.871.6109290K2300000
     
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