The most-commonly used spring materials include alloy steel, high carbon spring, stainless steel, non-ferrous alloy and high temperature alloy wires. For steel alloys, the primary materials are medium and high-carbon steels. Since the tolerance of precision springs lies in the storage and release of energy, the ideal material must have high resilient structure to withstand larger degrees of winding and deflections.
The use of certain spring materials should be considered based on its application and basic requirements for extensive elastic range. Other factors taken in account are costs, fatigue strength, formability, corrosion resistance, electrical conductivity and magnetic permeability, etc., in order to seek the best cost-effective solutions.
General commercial springs may have various surface quality while some degree of imperfections could be acceptable. The processing of steel alloys, however, relatively costs more in the spring production such as shock-absorbing springs and valve springs used in automobile industry. High surface quality of these spring materials free from any cracks and dents are strictly required to satisfy safety standards of vehicles, which in turn results in higher costs.
Some springs are stock products, but most of the springs are customized. Key points to consider for custom springs design are as follows::
- Based on the specific demands of the customers, determine the parameters, physical characteristics and tolerance requirements for either the torsion, extension or compression springs
- Find a spring factory to discuss feasibility of the design
- Layout alternative options
- Estimate the costs
Extension springs, compression springs and torsion springs are among the most in-demand in the spring market. Compression springs are mainly used to perform the function of pushing loads. They are the most common choice if larger deflections are required, or when the push mode is needed to store energy or to resist compressive forces. Torsion springs are usually used in doors, lids, or other mechanic designs that apply torque with spring arms to cause rotation around the central axis. Extension springs are more widely used than conical extension springs. Though both of them exercise pulling function, conical extension springs, however, are similar to constant-force extension springs that apply pulling tension force instead of torsion force to the loads.
Designed to be installed in devices, springs possess energy storage capacity. Springs store the kinetic energy from components during deceleration process, and release the energy during acceleration process to reduce the loads required for mechanic operation. Torsion springs are most commonly used in curtains and various door panels. Among all the above-mentioned springs, however, compression springs are the most widely used.