A torsion spring is the only component on an industrial door that ships with its own odometer. The cycle rating stamped on the wire counts down every time the door moves, yet most facilities never read it until the door dies half open over a busy dock. The motor gets the blame, and the worn spring that caused it stays uninspected on the shaft.
Our production team assembles every variant discussed here, and the differences show up long before the warranty does. Industrial door springs are simple parts with measurable lives, and the numbers are public. This page sets out the two spring types used on counterbalanced doors, how to read their performance figures, and where each type belongs. It ends with the specification lines that turn a spring enquiry into a matched order.
Spring Types Used on Industrial Doors
Two spring families carry the weight on counterbalanced doors. Torsion springs mount on a shaft above the opening and store energy by twisting. Extension springs stretch along the horizontal tracks on both sides. Most sectional and overhead doors in factories and warehouses run on one of the two.
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