The transportation industry, Agriculture implement manufacturers, and construction equipments manufacturers are some of the largest users of the hot coiled springs.Hot-coiled springs are generally used in elevated temperatures, high load applications, in a corrosive environment.
IIS can manufacturer hot coiled springs upto 92mm or 3.62 inch wire diameter and OD 450mm or 17inches.
Generally springs with bar diameter greater than 12.7mm (0.5 in.) are hot coiled. Bars of carbon or alloy steel are generally used for hot-coiled springs.(Details of material used is below) Since the material is special bar quality, hot-coiled springs are rather costly. For most hot-coiled springs, finished hardness requirement is in the range of Rockwell C 44-53.
IIS hot-coiled springs initially wound to a greater length than finished length. Since presetting allows supporting greater loads because of residual stresses removal resulting from presetting, most hot-coiled springs are preset. Then they are pressed one or more times to make the specified length. Shot Peering is also done on all hot coiled springs manufactured at IIS to increase service life. Magnetic particle inspection can be carried out if required.
IIS hot coiled springs can be made from peeled & centerless ground bar test for crack in our bar crack detection machine to ensure no failure. Automatic Grinders allow excellent surface contact which ensure parallelism and squareness.All springs are heat treated in calibrated electric furnace with controlled temperature.