What measures are needed to deform precision castings?

During the manufacturing process, castings will deform due to hardware facilities, management, casting cooling, correction and other issues. So, how to deal with the deformation of castings? Casting deformation is divided into micro self-deformation, casting expansion deformation and warping deformation. Micro deformation: Gray iron is prone to micro-deformation in alloy materials.

In addition to residual stresses such as cold cracks and casting deformation, residual stress is also the main cause of trace self-deformation. Even if the residual stress does not exceed the yield strength of the material, gray cast iron will slowly undergo microplastic deformation, that is, microdeformation and expansion, over a sustained period of time. Deformation: The reason for its formation is that the sand core or sand at the opening hinders the shrinkage of the casting, causing plastic deformation of the free structural part of the casting opening, resulting in opening deformation defects.

Warping deformation:

After sanding, the two ends of the casting, one end and even the outside are warped, causing the middle part of the casting to be dented, resulting in uneven casting, which is called warping deformation. The main reason is: during the cooling process, due to the uneven thickness or thickness of the casting, there is a temperature difference, and the casting Different cooling rates lead to uneven plastic deformation, leading to warping deformation.

This article proposes 4 measures for the deformation of precision castings:

1. Before waxing, put the mold into the waxing room until the temperature of the mold is the same as that of the waxing room, and then start waxing; as for the back shell, since there is no control or it is directly listed in the waxing room, there is no need to increase the temperature of the wax part .

2. After the wax pieces come out, mainly check whether the mold is deformed or have other defects during operation; the wax pieces should be placed neatly to avoid overlapping and hanging; after shipment, it is recommended to use inspection as much as possible to improve the detection speed and accuracy, and calibrate according to a certain period .

3. After opening the furnace, when the module temperature is still very high, overlap should be avoided and placed regularly to make the deformation direction consistent and facilitate the correction of the fashion clip.

4. Tools for correcting castings should be made of hard materials, and the surface should be wear-resistant. The tonnage of the press or punch machine should be calculated reasonably to avoid waste of equipment or insufficient power.

Precision castings have a great impact on the performance of mechanical products. Poor quality of precision castings will seriously affect the service life of mechanical products. Once deformation of precision castings is found, it should be corrected in time to avoid affecting the performance of precision castings.