Exceptionally long extension springs, developed to meet demands for unusual applications or maintenance operations, are now available from Lee Spring. Offered in 304.8, 609.6 and 914.4mm lengths, in music wire and 302 stainless steel, the springs can be cut to length to meet custom load requirements. The wire and outside diameters of the springs match Lee Spring's most popular stock extension spring products.
Various loops or hooks can be formed on the ends of these springs using looping pliers, although as wire size increases different tools and a vice are required to hold the coil body so the last coil can be bent to suit fastening requirements.
The spring rate per inch of extension at the final cut length is determined by using the formula: Spring Rate = K/N; where K = Stiffness and N = Number of Coils per inch multiplied by the length in inches. Load at an extended length is determined by multiplying deflection by spring rate.
A minimum of five pieces can be ordered of any item but Lee Spring advises customers to call to discuss specific requirements.