Stock Drive Products & Sterling Instrument - SDP/SI Datasheets for Constant Force Springs

Constant force springs are a variety of extension spring. A strip of steel with a preset curvature is coiled tightly so that each turn of the strip rests on its inner neighbor. The spring is actuated in a pulling, liner motion with the deflection resistance originating from the material's stiffness and spring construction. Unlike other extension springs, a consistent degree of force is exerted despite the degree of deflection.
Constant Force Springs: Learn more

Product Name Notes
Constant Force Neg'ator Springs (inch) -- A 3X50-SL04D16 Constant Force Spring: 0.23 lb Spring Force, 20000 cycles Fatique Life, 16" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SK04D15 Constant Force Spring: 0.32 lb Spring Force, 13000 cycles Fatique Life, 15" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SL05E17 Constant Force Spring: 0.36 lb Spring Force, 20000 cycles Fatique Life, 17" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SH03C10 Constant Force Spring: 0.37 lb Spring Force, 2500 cycles Fatique Life, 10" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SK04E15 Constant Force Spring: 0.4 lb Spring Force, 13000 cycles Fatique Life, 15" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SL05F30 Constant Force Spring: 0.43 lb Spring Force, 20000 cycles Fatique Life, 30" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SK05E16 Constant Force Spring: 0.49 lb Spring Force, 13000 cycles Fatique Life, 16" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SH04C14 Constant Force Spring: 0.49 lb Spring Force, 2500 cycles Fatique Life, 14" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SL06F24 Constant Force Spring: 0.52 lb Spring Force, 20000 cycles Fatique Life, 24" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SH04D14 Constant Force Spring: 0.66 lb Spring Force, 2500 cycles Fatique Life, 14" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SL06G24 Constant Force Spring: 0.7 lb Spring Force, 20000 cycles Fatique Life, 24" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SK06F23 Constant Force Spring: 0.71 lb Spring Force, 13000 cycles Fatique Life, 23" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SH04E14 Constant Force Spring: 0.83 lb Spring Force, 2500 cycles Fatique Life, 14" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SL08G31 Constant Force Spring: 0.93 lb Spring Force, 20000 cycles Fatique Life, 31" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SK06G23 Constant Force Spring: 0.95 lb Spring Force, 13000 cycles Fatique Life, 23" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SH05E15 Constant Force Spring: 1.03 lb Spring Force, 2500 cycles Fatique Life, 15" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SK08G30 Constant Force Spring: 1.26 lb Spring Force, 13000 cycles Fatique Life, 30" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SL10J33 Constant Force Spring: 1.46 lb Spring Force, 20000 cycles Fatique Life, 33" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SH06F21 Constant Force Spring: 1.48 lb Spring Force, 2500 cycles Fatique Life, 21" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SK08J30 Constant Force Spring: 1.58 lb Spring Force, 13000 cycles Fatique Life, 30" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SH06G21 Constant Force Spring: 1.97 lb Spring Force, 2500 cycles Fatique Life, 21" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SK10J32 Constant Force Spring: 1.98 lb Spring Force, 13000 cycles Fatique Life, 32" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SH16P38 Constant Force Spring: 10.6 lb Spring Force, 2500 cycles Fatique Life, 38" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SL25U59 Constant Force Spring: 11.7 lb Spring Force, 20000 cycles Fatique Life, 59" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SK25S57 Constant Force Spring: 11.9 lb Spring Force, 13000 cycles Fatique Life, 57" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SL31U69 Constant Force Spring: 14.40 lb Spring Force, 20000 cycles Fatique Life 69" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SK25U57 Constant Force Spring: 15.8 lb Spring Force, 13000 cycles Fatique Life, 57" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SH20R47 Constant Force Spring: 16.5 lb Spring Force, 2500 cycles Fatique Life, 47" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SK31U68 Constant Force Spring: 19.6 lb Spring Force, 13000 cycles Fatique Life, 68" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SH20S47 Constant Force Spring: 19.8 lb Spring Force, 2500 cycles Fatique Life, 47" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SL12K42 Constant Force Spring: 2.09 lb Spring Force, 20000 cycles Fatique Life, 42" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SK10K32 Constant Force Spring: 2.37 lb Spring Force, 13000 cycles Fatique Life, 32" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SH08G28 Constant Force Spring: 2.63 lb Spring Force, 2500 cycles Fatique Life, 28" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SL12P42 Constant Force Spring: 2.8 lb Spring Force, 20000 cycles Fatique Life, 42" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SK12K40 Constant Force Spring: 2.84 lb Spring Force, 13000 cycles Fatique Life, 40" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SH25S48 Constant Force Spring: 24.8 lb Spring Force, 2500 cycles Fatique Life, 48" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SH08J28 Constant Force Spring: 3.29 lb Spring Force, 2500 cycles Fatique Life, 28" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SL15P46 Constant Force Spring: 3.5 lb Spring Force, 20000 cycles Fatique Life, 46" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SK12P40 Constant Force Spring: 3.79 lb Spring Force, 13000 cycles Fatique Life, 40" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SH25U48 Constant Force Spring: 33 lb Spring Force, 2500 cycles Fatique Life, 48 48" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SH10J29 Constant Force Spring: 4.12 lb Spring Force, 2500 cycles Fatique Life, 29" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SL15R46 Constant Force Spring: 4.37 lb Spring Force, 20000 cycles Fatique Life, 46" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SK15P42 Constant Force Spring: 4.74 lb Spring Force, 13000 cycles Fatique Life, 42" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SH10K29 Constant Force Spring: 4.95 lb Spring Force, 2500 cycles Fatique Life, 29" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SH31U58 Constant Force Spring: 40.9 lb Spring Force, 2500 cycles Fatique Life, 58" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SK18P47 Constant Force Spring: 5.69 lb Spring Force, 13000 cycles Fatique Life, 47" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SL20R54 Constant Force Spring: 5.83 lb Spring Force, 20000 cycles Fatique Life, 54" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SH12K36 Constant Force Spring: 5.94 lb Spring Force, 2500 cycles Fatique Life, 36" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SL20S54 Constant Force Spring: 6.99 lb Spring Force, 20000 cycles Fatique Life, 54" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SH12P36 Constant Force Spring: 7.92 lb Spring Force, 2500 cycles Fatique Life, 36" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SL25S59 Constant Force Spring: 8.74 lb Spring Force, 20000 cycles Fatique Life, 59" Band length
Constant Force Neg'ator Springs (inch) -- A 3X50-SK20S52 Constant Force Spring: 9.48 lb Spring Force, 13000 cycles Fatique Life, 52" Band length