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News & Knowledge

How to solve the deformation problem of induction quenching parts?


There are many forms of deformation of High frequency induction heating machine quench parts, such as shaft, residual weight of the dome field, nine of the size of the uniform, reduced dynamic mountain degree, disc deflection, ball screw pitch expansion, single tooth quench pitch cumulative error


(1) The bending distortion of the slender shaft when the scanning quenching slender thin parts, the solution is added


1) Relax the top, with the spring top, pneumatic top political division can be field elongation, to eliminate the workpiece and beat point long resistance.


2) Add a calibration roll, when the inductor through can automatically move away, with a function similar to the lathe center frame.


3) To make the effective ring and the injector as concentric as possible with the workpiece, the heating temperature and cooling speed are uniform on the circumference, and the resulting bending will also be reduced.


(2) The bending distortion of the strip shaped workpiece often occurs in the single quenching sag distortion, the solution is as follows:


1) Symmetrical quenching.If the workpiece technical requirements permit, the two sides simultaneously scan quenching, will reduce distortion, there is in the opposite side of the quenching surface with flame heating, can reduce distortion.


2) Bending.This method has been applied to the surface quenching of rail by prebending the profile of the part to be quenched.


3) After the inner hole inner surface quenching distortion cylinder liner general within the aperture shrinkage, the reason is that the outer wall of cylinder liner with water cooling, the inner surface after quenching, organization size can’t outward expansion can only squeeze inside, so narrow aperture, the distortion is regular, can modify the amount of reserve grinding honing process followed, the aperture is slightly increased before quenching, offset quenching of shrinkage.The same treatment can be used for the complete tooth quenching of the inner ring.


(4) The deformation in the process of heating sheet parts such as woodworking saw blade Φ mmx3mm, 500 teeth of high frequency induction hardening.The workpiece in the process of heating will wave distortion, wu highly rules, this is because the local temperature unevenness is produced by thermal stress, after adopting the workpiece in ordinary oven preheated to 650 ℃ and the high frequency induction heating, the temperature from 800 ℃ to 150 ℃, the thermal stress on the saw blade is reduced, distortion, no longer make tooth of high frequency induction hardening is completed.


(5) The measures to reduce the gear quenching deformation are as follows:


1) Prevent the reduction of gear inner hole.

Many machine tool factories summed up this experience, some machine tool factories require gear quenching, inner hole shrinkage < 0.005mm, or < o. 01mm, and general high-frequency induction quenching, inner hole shrinkage often 0.01~0.05mm;Some factories will spline first preheat the inner hole, and then quenching the external teeth;Some factories add high temperature tempering process to thick wall gear after rough gear billet, and then add high frequency induction normalizing to generate stress, and then fine drawing spline, cutting teeth, shaving teeth, high frequency induction quenching, low temperature tempering, can control the inner hole shrinkage within 0.005mm.


2) For gear with tooth quenching, the tooth of the last quenching has the largest quenching deformation.Therefore, the method of quenching by tooth to reduce deformation is to conduct quenching alternately, that is to separate one or two teeth for quenching.