Tensile spring initial tension and initial stress

A little difficult to understand: "initial tension" and "initial stress"

When calculating the load of a tension spring, we consider an unfamiliar force called initial tension. Initial tension is the force that causes the coils to want to adhere to each other, and it can be determined from the wire diameter, the average coil diameter, and "initial stress." However, in the literature, it is stated that there is a certain range for the value of "initial stress," and it is troublesome as it suggests selecting an appropriate value from that range. In fact, initial tension can be adjusted by us manufacturers by winding it tightly or loosely. (We adjust the strength by changing the settings of the spring processing machine.) To put it somewhat roughly, the "range of adjustment" on the manufacturer's side is quantified as the "range of initial stress." Even if the springs appear to have the same specifications, if the manufacturer applies a strong "initial stress," it will result in a spring with strong initial tension. Initial tension and initial stress are concepts that are difficult to understand just by reading books. (For more information on initial tension, please refer to the related links.) If you have any questions, please feel free to contact us by phone or email. Tsurugaoka Spring Co., Ltd. Contact: Ujiie Phone: 0235-22-0407 FAX: 0235-22-0546 Email: web@tohj.com

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