Torsion Spring Design

Spring manufacturers develop torsion springs to varying specifications of load, wind, deflection, spring rate and other properties. There are many factors to consider when it comes to torsion spring design. Spring design variables depend greatly upon the application in which they will be used. When specifying torsion springs, things to consider include:

• Dimensional constraints
• Rod usage
• Body length
• Leg bend and length
• Deflection length
• Required torque
• Free length angle
• Material

Another variable to consider is the application environment in which the torsion springs will be used. For example, torsion spring exposed to harsh weather conditions or regular contact with moisture, may require a corrosion resistant material like stainless steel or a corrosion resistant finish. Common finish options include black oxide, passivate, zinc plating and more. Another important environmental element to think about is the temperature in which the spring will be used. Carbon steels are only suitable up to 250 degrees F, whereas stainless steel can handle up to 550 degrees F. These key environmental elements will directly affect a spring design.

Torsion spring design is usually more complex than compression and extension springs. Not only are there way more variables to consider, but there are an infinite number of ways to bend and twist the legs of a torsion spring. The leg design completely depends on the application and can be extremely difficult to describe. The best practice to ensure the legs are bent to the required specs, is to provide a detailed print or sample. To note, the more bends a torsion spring has the higher the cost.

Due to the complexity of torsion spring design, it is important to source torsion springs from an experienced manufacturer to assure proper design and superior quality to meet the required performance.

W.B. Jones has over 100 years’ experience providing quality torsion springs, both stock and custom to meet your needs.