Decomposition of abnormal quality of mobile phone shielding cover

Breakdown of abnormal quality problem of mobile phone shielding cover 1: Pressure injury on the inner and outer sides of the mobile phone shielding cover bending: There are two situations (1) Small hole skipping waste, large hole skipping waste: long-term production causes the punch knife edge to wear and the gap becomes larger, and it cannot be stuck. The waste material is taken out of the die surface by the punch, causing crushing. (2) Powder crushing: The gap between the punch and the knife edge is too large or too small to cause the powder to scatter on the die surface. When the stamping material passes through the leveler and the feeder, the product will be directly crushed because of the dust and fine iron filings in the machine. Two: Small hole cut burrs and burrs at the creases of the mobile phone shielding cover products: The gap between the punch and the knife edge is too large to cause burrs or the punch is shifted to one side, resulting in burrs on one side and no burrs on the other side. The last step of the shielding cover is made with a cut-and-fold structure, and the punch is worn out after a period of production, and it is easy to produce burrs. In the last step, because the material is not pressed or the bending punch pulls the material, it will cut more on one side and less on the other, and the less side will protrude and cause poor size. In the last step, sometimes the guide pin pulls the material to be knocked off, which will cause unstable bending and shearing dimensions. Three: Bending angle External tension and internal buckle: External tension, the mold is not crushed; the mold is compressed with large waste, the product; the gap between the bending punch and the insert becomes larger; the bending inserts are worn or collapsed. The angle is flared. Internal buckle, die pressure is too strong; bending inserts have too high pressure ribs; the gap between the bending punch and the inserts is too small, which will cause the angle internal buckle. Four: Side scratches: the bending punch or the bending insert is worn; the gap between the bending punch and the insert is too small; the bending punch and the insert are stuck with waste; less fuel will cause scratches. Five: The bending height is not general: the step distance is not adjusted to send more or less; the bending punch inserts shift; the bending gap is tight while the other is loose, resulting in material pulling. Sometimes the same bending edge is high and the other is low because the product swings or the position of the bending punch insert is wrong. Six: Product deformation, arched shape, imprinted with screws, stamping: product deformation, material distortion is not too flat; insufficient pressing force causes stripping deformation; template deformation; leveling screw height is not adjusted properly or for flatness The screw is deformed. The product is arched, the mold is not pressed in place, and the waste product is pressed inside the mold to cause the arch. The upper and lower mouldings are too dead; the inserts higher or lower than the mould surface will leave the stamping marks on the product. Seven: The feet are deformed and broken: the feet are deformed, and the position is not enough; the leveling screw hits the bent edge; the spring breaks and the material is not smooth and deforms. If the foot is broken, the die will be broken if the die is pressed too hard and the pressure rib is too high; the scrap material between the bending punch inserts will cause violent friction and break. Eight: Poor product flatness: material distortion is not too flat; the height of the bending edge is not uniform; the height and width of the bead on the bending insert are not uniform, resulting in unbalanced stress and material instability and deformation; uneven deformation of the template can not hold the material . Nine: The small convex hull of the mobile phone shielding cover is gone, small and large: the needle for punching the convex hull is short and worn; the mold is not crushed; the waste product in the mold will cause the convex hull to be small and disappear; bending inserts Insufficient avoidance and insufficient mold avoidance will squash the small convex hull. The needle for punching the convex hull is higher; the larger diameter of the working part will cause the convex hull to be too large or even rupture. Ten: The mobile phone shielding cover is too loose and too tight: the frame dimensions go to the lower limit, and the cover dimensions go to the upper limit, and the assembly is loose. If the cover is outside the frame, the inner buckle assembly will also be loose; when the clearance is reasonable, the diameter and height of the bump Affect the tightness of the assembly.