Process analysis of heat treatment of spring chuck using medium frequency induction heating machine

Spring chuck is a machine tool accessory that uses the elastic deformation of the clamping jaw to center and clamp the workpiece or tool. Spring collets are usually installed in the hole of the machine tool spindle. It can be seen from the working environment of the spring collet that the spring collet has to withstand huge friction during the working process. Therefore, how to improve its service life has become the primary issue. Usually, we use a medium frequency induction heating machine to quench and heat treat it, so that its service life can be improved. Today, we will take a look at the new process of quenching spring collets using a medium frequency induction heating machine.

With conventional heat treatment, although the hardness of the transition zone can reach 47-51HRC, microcracks are easily formed in the rounded transition zone due to shape factors and quenching factors. In order to reduce the defects here, we redesigned the heat treatment process: using a medium frequency induction heating machine for induction heating heat treatment at 820-840℃x6min, grading in nitrate salt at 170-180℃ for 4min, and then performing 390-410℃x1h Tempering heat treatment. When tempering, the head of the spring collet is upward, leaving 5mm on the upper part of the base body, and the rest is immersed in nitrate salt at 400°C. In this way, the base body of the spring collet obtains a tempered troostite structure with a high elastic limit, and the rounded transition zone obtains a composite structure with a high strength limit, ensuring the comprehensive performance requirements of the spring collet during operation.

How to improve the service life of workpieces has always been a common concern. Today, we briefly introduced the heat treatment process to increase the service life of spring collets. After using this heat treatment process, the average life of spring collets reaches 26,000-30,000 pieces. The service life is increased by 3 times compared with conventional treatment.