December 8, 2023
Wrinkles and creases:
The main reason for wrinkles is that local blank pressure causes instability and uneven material flow causes local material accumulation and wrinkles. Specifically, there are the following aspects:
(1) The stamping process of the parts is poor, the stamping direction and the shape of the pressing surface are improperly determined, and it is difficult to control the flow speed of the material, causing wrinkles.
(2) The feeding resistance of the pressing surface is too small, and excessive feeding will cause wrinkles. At this time, the pressure of the outer slider can be adjusted or the local shape of the drawing blank can be changed, the pressing area can be increased to eliminate it, or the drawing rib can be partially added to increase the feeding resistance.
(3) The contact between the pressing surface and the pressing surface is not good, and in severe cases, the inside is loose and the outside is tight. After the material passes through the outer tight area, the pressing ring loses its pressing function, resulting in excessive feeding and wrinkles. At this time, the pressing surface needs to be re-ground to ensure full contact, and a slight tightness on the inside and looseness on the outside is allowed.
(4) Too much oil and lubrication.
(5) Improper adjustment of the outer slider causes tilt, uneven pressure on the pressing surface in various places, and loose areas are prone to wrinkles.