What are the most common quality defects of stamping dies? The most common quality defect of molds produced by stamping with coated sand equipment is that the product size is out of tolerance, and only a few products have surface quality problems. Out of tolerance is a serious defect of stamping parts. In this regard, first of all, the design of the mold should be inspected and tested to eliminate the reasons for design and manufacturing. If the out-of-tolerance size is related to the thickness of the material, the thickness, material and hardness of the stamping material should be tested. The out-of-tolerance caused by stamping production process is mainly due to die wear, poor positioning and guidance and deformation of parts. Wear of die cutting edge will cause excessive burr or cutting size, smaller punching hole and out-of-tolerance flatness, so the die should be sharpened or replaced. Poor positioning and guidance include no guidance, no guide pin or other positioning device, no looseness of feeder, too long feeding distance caused by abrasion of positioning block, wrong length of guide plate or too large guide gap, etc. The deformation of parts in production mainly includes impact deformation, such as excessive blowing pressure or excessive deformation caused by gravity drop; If it is squeezed or bruised during discharging, the discharging part shall be cleaned in time or the discharging space shall be enlarged; Improper deformation should be caused by ejection. For example, if the thimble is improperly prepared, the spring force is inappropriate or the ejection is too long, it is necessary to adjust the elastic force or change the position or quantity of the thimble; Blanking deformation. Some bent parts are not allowed to overlap, so they fall down every time. When disc strain occurs, it can be eliminated by pressing pad. Stamping and shearing deformation are mainly caused by uneven materials. Increase in size or asymmetry in center; The extrusion deformation of floating chips is due to the floating of waste, the extrusion deformation of fine chips or foreign bodies left on the surface of the die. The surface quality problem of stamping parts with unqualified surface quality is mainly excessive burr. The reason for the excessive burr of parts is that the cutting edge of the die is worn, and the die (as described below) should be re-polished to ensure the sharp cutting edge. Secondly, the interval between convex and concave dies is unreasonable. If the gap is too large, most of the sides are polished, and if the gap is too small, a secondary shear surface will appear. If the hardness of the material is too high, replace the material or increase the gap. If the blanking overlap size is too small or the trimming material is too small, the material will be pulled into the die gap and become burrs. At this point, it is necessary to increase the overlapping size or trimming margin of blanking. Qingdao Tiangong Machinery Equipment Co., Ltd., namely Qingdao Tiangong Machinery Co., Ltd., is a specialized company engaged in R&D, manufacturing, installation and service of casting machinery in China. clay sand production line