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　　The method of large-scale gantry grinding to prevent the deformation of large-scale mold processing workpieces: the disordered mold should be heated slowly under the phase change point, generally speaking, the deformation of mold vacuum heat treatment is much smaller than that of salt bath furnace heating and quenching. Choose preheating, for low alloy steel mould, choose one time preheating; for high alloy diamond mould, choose two times preheating.

　　It is not correct that the deformation of the die after heat treatment is generally considered to be formed by cooling. The large-scale gantry grinding processing mold, especially the disordered mold, whether the processing technology is correct or not often has a greater impact on the mold deformation. The comparison of some mold heating technology can be seen clearly that the heating speed is faster, often has a greater deformation.

　　Jiangmen large grinder processing

　　There is also a point that any metal will swell when it is heated, because when the steel is heated, the uneven temperature of each part (i.e. uneven heating) in the same mold will inevitably form the inconsistent swelling of each part in the mold, thus forming the internal stress of uneven heating. When the large-scale gantry mill is processed at the temperature below the transformation point of the steel, the uneven heating mainly produces thermal stress. When the temperature exceeds the transformation temperature, the heating is uneven, and there will also be the unevenness of the arrangement change, which is the arrangement stress. Therefore, the faster the heating speed, the greater the temperature difference between the die surface and the core, the greater the stress, and the greater the deformation of the die after heat treatment.