Haituo_CN_Website > HaiTuo_EN_Website > News > > Analysis of spring quenching technology

Analysis of spring quenching technology

At present, large spring forming heating and quenching heating, mostly using a flame furnace or an electric furnace. In order to prevent or reduce surface oxidation and decarburization, a higher surface quality is obtained, and a furnace capable of controlling the atmosphere is preferably used, or the atmosphere in the furnace is slightly reduced, and a high-temperature rapid heating method is employed. For medium and small springs, quenching heating can be carried out using a salt bath furnace with good deoxidation.
For general hot coil coil springs, hot-bending leaf springs, and hot stamped disc springs, it is preferred to use the remaining heat immediately after hot forming. This saves one heating and reduces the degree of oxidative decarburization of the spring, which is economical and improves the surface quality of the spring. For example, the heat treatment process currently used for leaf springs is after oil-hardening at 850-880 °C after 900-925C bends. If limited, it is also possible to reheat the quenching after forming.
The cold-formed spring has a large residual stress, and when quenched and heated, the deformation is large due to the release of residual stress. In order to ensure the dimensional accuracy of the spring, a stress relief annealing treatment can be added before quenching, which can reduce the degree of quenching heating deformation.
The quenching temperature of the spring can depend on the critical temperature of the spring material. In the metallographic structure of the spring material after quenching, there should be no free ferrite and cementite to avoid uneven deformation or fatigue strength. When quenching and heating, oxidation and decarburization should be prevented as much as possible. In order to ensure the quality of the spring, the depth of the decarburization layer is clearly defined in the technical standards of the spring steel and the technical conditions for the manufacture and acceptance of various metal springs.
Spring quenching should be cooled in oil to avoid deformation and cracking. Springs made of larger carbon steel materials can be water cooled when the requirements are not high.
At the same time, using the correct heating and cooling methods, sometimes special quenching jigs are used for forming quenching, which can reduce the deformation amount, for example, the leaf spring is quenched on the bending machine, and the medium and small coil springs are mounted on the mandrel or on the special fixture. Heating and cooling.
 © 2020 Dongguan Haituo Electromechanical Equipment Co., Ltd. all rights reserved 粤ICP备14033160号-2  粤公网安备 44190002003728号