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    34 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—The most secure attachment method. With fully closed loops, there's no risk of slipping off.
    Hook End—Hook into closed holes, such as hanger bolt eyes. These springs work best when kept under tension, as they're more likely to slip off than loop-end springs when tension is released. Also known as machine hook ends.
    Elongated-Hook End—With deeper hooks than standard hook end springs, these are less likely to slip off. However, they’re more prone to breaking if overstretched.
    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.
    Loop End
    Image of Product. Front orientation. Extension Springs. Loop End.
     
    Spring Steel
    3.75"0.375"0.041"5.81"1.264.371.51600000000000000
    3.75"0.375"0.041"8.721"1.158.681.4960000000000000
    3.75"0.437"0.055"5.74"2.7612.084.671000000000000
    3.75"0.438"0.048"6.85"1.658.022.066000000000000
    3.75"0.5"0.055"6.49"2.110.613.11000000000000
    3.75"0.625"0.113"4.75"24.0292.4268.41000000000000
    3.75"1"0.11"5.153"8.7133.117.3810000000000000
     
    Corrosion-Resistant 302 Stainless Steel
    3.75"0.375"0.041"6.37"1.264.71.3110000000000000
    3.75"0.437"0.055"5.45"2.7610.54.061000000000000
    3.75"0.5"0.055"6.18"2.19.252.71000000000000
    3.75"0.5"0.072"4.65"6.4916.8910.5410000000000000
     
    Hook End
    Image of Product. Front orientation. Extension Springs. Hook End.
     
    Spring Steel
    3.75"0.719"0.105"4.96"10.3144.328.0930000000000000
    3.75"0.75"0.105"4.39"13.1230.5827.13100000000000
     
    Corrosion-Resistant 302 Stainless Steel
    3.75"0.5"0.054"7.75"29.92.0610000000000000
    3.75"0.562"0.072"6.15"4216.9210000000000000
    3.75"0.75"0.105"4.56"13.1232.1623.591000000000000
    3.75"1"0.12"4.71"12.8335.2423.361000000000000
     
    Elongated-Hook End
    Image of Product. Front orientation. Extension Springs. Elongated-Hook End.
     
    Spring Steel
    3 3/4"0.563"0.072"4.21"4.1317.629.4430000000000000
     

    Compression Springs

    Image of Product. Front orientation. Compression Springs.
    Squeeze these springs and they’ll push right back to their original length. When compressed, they apply steady pressure to keep components securely in place. Release the pressure and they snap back instantly, just like the tip of a ballpoint pen.
    Spring Steel—Strong and resilient, but best suited for dry environments since moisture will cause these springs to rust.
    Lg.
    OD
    ID
    Wire
    Dia.
    Compressed Lg.
    @ Max. Load
    Max. Load,
    lb.
    Spring Rate,
    lbf/in
    End Type
    Pkg.
    Qty.
    Pkg.
    Spring Steel
    3.75"0.812"0.543"0.135"3.08"78120Closed and Ground600000000000000
     

    Long-Life Rubber Compression Springs

    Image of Product. Front orientation. Compression Springs. Long-Life Rubber Compression Springs.
    When longevity matters most, these springs deliver. Made from a polyester/rubber blend, they stay springy longer than metal and plastic springs—with documented cases up to one million cycles.
    Flanges on the ends create a flat mounting surface.
    Hardness—As the durometer gets higher, the springs absorb more energy but compress less.
    Flange
    Lg.
    OD
    ID
    OD
    Thk.
    Compressed Lg.
    @ Max. Load
    Max. Load,
    lb.
    Spring Rate,
    lbf/in
    Hardness
    Temp. Range,
    ° F
    Each
    3.75"4.5"3"5.69"0.61"2.3"1,700910Durometer 55D-40 to 1200000000000000

    Drilling Screw-Style Hangers

    Image of Product. Front orientation. Hanger Bolts. Drilling Screw-Style Hangers.
    Drill holes with the point on these hangers. Install with a special driver bit (sold separately).
    Zinc-Yellow-Chromate-Plated Steel—Zinc-yellow-chromate-plated hangers are corrosion resistant in wet environments.
    3/8" Wide Head—Zinc-yellow-chromate-plated hangers with a 3/8" head width can drill through steel sheet metal as thick as 16 ga.
    Hanger Bolts
    Driver Bits
    Head
    Screw
    Size
    Drill Tip
    Lg.
    Max. Drilling
    Thk.
    Lg.
    Threading
    Thread
    Lg.
    Eye
    Dia.
    Thk.
    Ht.
    For Use In
    Pkg.
    Qty.
    Pkg.
    Each
    Zinc-Yellow-Chromate-Plated Steel
     
    3/8" Wide Head
    1/4"
    		1/4"1/32"3 3/4"Partially Threaded2 1/2"3/16"3/32"1 1/8"Sheet Metal250000000000000000000000000000
     

    Slotted Spring Pins

    Image of Product. Front orientation. Spring Pins. Slotted Spring Pins.
    Image of Product. End View. Side1 orientation. Spring Pins. Slotted Spring Pins.

    End View

    Squeeze these pins into holes and they expand slightly, creating tension to hold parts in place. They are often used as hinge pins and as fasteners for springs and power transmission components. An alternative to dowel pins, they're lighter in weight with a hollow center and don’t need a precise hole. Also known as roll pins.
    Spring Steel—These pins won't deform from stress and vibration. Although they're stronger than stainless steel, they're best for dry environments since moisture will cause them to rust.
    Zinc-Plated Spring Steel—These pins withstand occasional exposure to moisture. However, since friction from moving parts can wear away the finish, they're not ideal for wet environments. While not nearly as corrosion resistant as stainless steel, they are stronger and won’t deform under stress.
    Corrosion-Resistant 18-8 Stainless Steel—The choice for wet and outdoor environments, these pins resist rusting. They are strong enough to join most components but won't withstand extreme stress and vibration as well as steel.
    Wear-Resistant 400 Series Stainless Steel—Our most wear-resistant stainless steel pins, these are good for pivoting parts that create a lot of friction. They hold up in environments that experience occasional moisture, but they're not as corrosion resistant as 18-8 and 316 stainless steel.
    Lg.
    For Hole Dia.
    Wall
    Thk.
    Double Shear Breaking
    Strength, lbf
    Min.
    Hardness
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Spring Steel
     
    5/16" Diameter
    3 3/4"0.312" to 0.318"0.062"10,800Rockwell C43ASME B18.8.225000000000000000
     
    3/8" Diameter
    3 3/4"0.375" to 0.382"0.077"16,300Rockwell C43ASME B18.8.21000000000000000
     
    1/2" Diameter
    3 3/4"0.5" to 0.51"0.094"27,000Rockwell C43ASME B18.8.21000000000000000
     
    Zinc-Plated Spring Steel
     
    5/16" Diameter
    3 3/4"0.312" to 0.318"0.062"10,800Rockwell C43ASME B18.8.2100000000000000
     
    3/8" Diameter
    3 3/4"0.375" to 0.382"0.077"16,300Rockwell C43ASME B18.8.21000000000000000
     
    1/2" Diameter
    3 3/4"0.5" to 0.51"0.094"27,000Rockwell C43ASME B18.8.250000000000000
     
    Corrosion-Resistant 18-8 Stainless Steel
     
    5/16" Diameter
    3 3/4"0.312" to 0.318"0.062"6,300Not RatedASME B18.8.250000000000000
     
    3/8" Diameter
    3 3/4"0.375" to 0.382"0.077"9,500Not RatedASME B18.8.210000000000000
     
    1/2" Diameter
    3 3/4"0.5" to 0.51"0.094"15,800Not RatedASME B18.8.210000000000000
     
    Wear-Resistant 400 Series Stainless Steel
     
    5/16" Diameter
    3 3/4"0.312" to 0.318"0.062"10,800Rockwell C43ASME B18.8.2500000000000000
     
    3/8" Diameter
    3 3/4"0.375" to 0.382"0.077"16,300Rockwell C43ASME B18.8.210000000000000
     
    1/2" Diameter
    3 3/4"0.5" to 0.51"0.094"27,000Rockwell C43ASME B18.8.210000000000000
     
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