At SPS (Southern Precision Spring), the quality and durability of our springs hinge on one critical step: optimizing the strength of our material. When springs are coiled, they undergo significant stress due to bending and other physical manipulations. But how do we restore and even enhance their strength?
Importance of Controlled Heating in Spring Production
Spring manufacturers utilize specific durations and temperatures of heat, based on the material type and size, to revitalize the strength of the spring to levels even surpassing their original state. It's a common misconception that the higher the temperature and longer the duration, the better. However, each material we use at SPS has its optimal "sweet spot" of heat treatment. Going beyond this optimal range can be counterproductive, causing more damage than enhancement.
Understanding Material Reaction to Heat
Materials respond differently to heat treatments. For instance:
Music Wire typically shrinks in diameter when heated.
Most Stainless Steel variants expand with heat, with a notable exception: 17-7 Stainless Steel. Its unique composition ensures it remains stable even at elevated temperatures.
Another factor to consider is the coil count. The number of coils influences the spring's rotation during heat treatment. A five-coil spring might shift by 10 degrees, while a spring with 100 coils might undergo a full rotation. Moreover, depending on the winding direction (left-hand or right-hand), springs can rotate either clockwise or counterclockwise.
Such nuances underline the importance of deep knowledge regarding material type, heat effects, and winding direction. Before finalizing our "Green" parts, we always pass them through controlled heat treatment. This process ensures that our finished products align perfectly with desired specifications and quality standards.