What are the types of plastic notches and stamping materials?
The scrap is essentially the inverse of the shaped hole. That is, the same position is in the opposite position. By checking the scrap, you can judge whether the gap between the upper and lower dies is correct. If the gap is too large, the scrap will present a rough, undulating fracture and a narrow bright band area. The larger the gap, the larger the fracture angle and the larger the bright band area. If the gap is too small, the scrap will present a small angle fracture and a wide bright band area.
The gap that is too large forms a hole with large curling and torn edges, making the profile slightly prominent and the edges very thin. If the gap is too small, it will produce strips with slight curling and large angle tearing, resulting in parts that are more or less perpendicular to the surface of the material. The ideal scrap should have a reasonable crushing angle and a uniform bright band. This can keep the stamping pressure small and create a neat round hole with small burrs. From this point of view, increasing the gap to extend the mold life is at the expense of the quality of the finished hole.
Plastic mold
Selection of plastic mold gap
The gap of the mold is related to the type and thickness of the stamping material. Ignoring the gap will lead to the following problems:
(1) If the gap is too large, the burrs of the stamped parts to be processed will be relatively large, and the stamping quality will be poor. If the gap is too small, although the stamping quality is good, the mold will be seriously worn, which greatly reduces the service life of the mold and easily causes the punch to break.
(2) If the gap is too large or too small, it is easy to cause adhesion to the material being stamped, thereby producing strips during the stamping process. If the gap is too small, it is easy to form a vacuum between the bottom of the punch and the sheet, and the waste will rebound.
(3) Reasonable gap can extend the service life of the mold, improve the discharge effect, reduce burrs and flanging, keep the sheet clean, the gap will not scratch the sheet, reduce the number of sharpening times, keep the sheet straight, and accurately press and position.