Why does the copper bar produce twisting and twisting during stamping
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What problems will happen to copper bars when stamping parts??What is the reason for the twisting of the material??1.The reason for turning over and twisting during stamping is in the progressive die, by punching the remaining material around the stamping part to form the shape of the stamping part.The main reason for the turning and distortion of the punching parts is the influence of the punching force.When punching, due to the existence of the punching gap, the material is stretched on one side of the die (the material is warped upward), and compressed on the side of the punch.When using the unloading board, use the unloading board to compress the material to prevent the material on the die side from warping upwards. At this time, the force of the material changes accordingly.As the discharge plate increases its pressing force, the material on the punch side is stretched (compression force tends to decrease), while the material on the concave die surface is compressed (tension force tends to decrease).The overturning of the stamping part is caused by the stretching of the material on the die surface.Therefore, when punching, pressing and pressing the material is the key point to prevent the punching from turning over and twisting..2.Method of restraining stamping parts from turning over and twisting (1).Reasonable mold design.In the progressive die, the arrangement of the blanking sequence may affect the accuracy of stamping parts forming.For the blanking of small parts of stamping parts, generally a larger area of punching and blanking is arranged first, and then a smaller area of punching and blanking is arranged to reduce the impact of the punching force on the forming of the stamping part.(2).Hold down the material.Overcome the traditional mold design structure, open a material-containing gap on the discharge plate (that is, when the mold is closed, the discharge plate is attached to the concave mold, and the gap between the discharge plate and the concave mold where the material is contained is the material thickness t-0.03～0.05mm).In this way, the unloading plate moves smoothly during stamping, and the material can be compressed.The key forming part, the unloading plate must be made into a block-type structure to facilitate the solution of the wear (compression) loss of the pressing part of the unloading plate caused by long time stamping, and the material cannot be compressed.(3).Add strong pressure function.That is to increase the size of the press part of the unloading insert (normal unloading insert thickness H+0.03mm), in order to increase the pressure on the material on the side of the die, so as to prevent the stamping parts from turning over and twisting during punching..(4).The end of the punch edge is trimmed with a bevel or arc.This is an effective way to reduce cushioning and cutting power.By reducing the buffer cutting force, the tensile force on the side material of the die can be reduced, so as to achieve the effect of suppressing the turning and twisting of the stamping parts..(5).In daily mold production, care should be taken to maintain the sharpness of punching convex and concave die cutting edges.When the punching edge is worn, the tensile stress on the material will increase, so the tendency of stamping parts to turn over and twist becomes greater.(6).Unreasonable blanking clearance or uneven clearance is also the cause of turning over and distortion of stamping parts, which needs to be overcome.3.Handling of common specific problems in production. In daily production, you will encounter situations where the punching size is too large or too small (may exceed the specification requirements) and the size of the punch is large. In addition to considering the design of the forming convex and concave molds In addition to factors such as size, machining accuracy and blanking gap, the following aspects should also be considered to solve.(1).When the punching edge is worn, the tensile stress of the material increases, and the tendency of the stamping part to turn over and twist increases.When turning the material, the punching size will become smaller.(2).The strong pressure on the material causes plastic deformation of the material, which will cause the punching size to become larger.When the strong pressure is reduced, the punching size will become smaller.(3).Shape of punch edge.If the end is trimmed with a bevel or arc, the punching force is slowed down, and the punching part is not easy to turn over and twist. Therefore, the punching size will become larger.When the end of the punch is flat (no bevel or arc), the punching size will be relatively small.In the specific production practice, specific analysis should be made for specific problems, so as to find out the method to solve the problem.Yueqing Renhe Electronics Co., Ltd. specializes in the production of automotive new energy accessories, copper bars, flexible connections, copper terminals, copper noses, terminal blocks, sheaths, etc..