Sheet metal fabrication includes a variety of means, including loading and unloading, cutting, bending, welding and forming, etc. However, in the process of sheet metal fabrication, deformation sometimes occurs, which requires corresponding measures to be taken in the process of sheet metal fabrication to prevent the occurrence of deformation so that the finished parts can be used normally. So what are the causes of deformation in sheet metal fabrication? The causes of sheet metal fabrication deformation.
1.The role of internal forces leads to the change of the machining accuracy of the parts
When lathe fabrication, usually the role of centripetal force is used, with the lathe’s three-jaw or four-jaw chuck, the parts are stuck tight, and then the sheet metal parts are processed. At the same time, the clamping force must be greater than the cutting force of the sheet metal in order to ensure that the part does not loosen and reduce the internal radial force when it is under stress. The clamping force increases as the cutting force increases and decreases with it. This is the only way to ensure that the forces on the sheet metal parts are stable during machining. However, after the three-jaw or four-jaw chuck is released, the machined sheet metal parts will be very different from the original ones, with some showing polygonal shapes and some showing oval shapes, with large deviations.
2.The problem of deformation easily arises after heat treatment fabrication
For sheet metal parts of the thin sheet category, due to their very large length and diameter, they are prone to the bending of the straw hat after heat treatment. On the one hand, the phenomenon of bulging out in the middle will appear, and the plane deviation will increase, on the other hand, due to the influence of various external factors, so that the parts produce bending phenomenon. These deformation problems arise not only because the internal stress of the parts after heat treatment has changed, there is also the operator’s professional knowledge is not solid, do not quite understand the structural stability of the parts, thus increasing the probability of deformation of the parts.
3.Elastic deformation caused by external forces
There are several main reasons for the elastic deformation of parts in sheet metal fabrication. Firstly, if the internal structure of some parts contains thin sheets, there will be higher requirements for the method of operation, otherwise the correspondence between the operator in positioning and clamping the part and the design of the drawing cannot be carried out, which will easily lead to the generation of elastic deformation. Secondly, the unevenness of the lathe and fixture makes the part unevenly stressed on both sides when it is fixed, resulting in a small force on the side of the cut when the force is applied and the part is deformed. Thirdly, the positioning of the part in the machining process is unreasonable, which reduces the rigidity and strength of the part. Fourth, the presence of cutting forces is also a cause of elastic deformation of the part. These different causes of elastic deformation all illustrate the effect of external forces on the quality of sheet metal part fabrication.
