How to solve the problem that the punching size of automotive hardware stamping parts does not meet the requirements?

2021-03-30 10:07:05

In the process of metal stamping, the situation of large or small punch size and the large difference with punch size will be encountered. In order to solve such problems, we should consider the planning size, processing accuracy and blanking clearance of forming convex and concave die, and think about it from the following aspects.

1. In the production of metal stamping parts, the rough edge of the punching parts produced during blanking shall be studied and repaired, and the clearance of blanking shall be checked to see if it is reasonable. The main problem is to solve the problem that the stamping parts are unstable during bending, mainly for U-shaped and V-shaped bending, leading position before bending, guiding position in bending process, and pressing material to prevent the stamping parts from slipping during bending.

2. In the production of metal stamping parts, the tensile stress of the material increases, and the tendency of turning and twisting of stamping parts is increased. When the material is turned, the punch size will be smaller. The strong pressure on the material causes plastic deformation of the material, which will lead to the larger size of the punch. When the pressure is reduced, the size of the punch will be smaller.

3. In the production of metal stamping parts, such as the end of the repair of inclined surface or arc, because of the relief of blanking force, stamping parts are prone to flip, stigma, so the size of the punch will be larger. The punch end is flat, and the punch size will be smaller.

Inspection method of automobile stamping parts

1. touch test

Clean the surface of the outer covering with clean gauze. The inspector shall wear touch gloves to touch the stamping parts vertically and closely to the surface of the stamping parts, which depends on the experience of the inspector. If necessary, the suspected areas can be polished and verified by oilstone, but this method is an effective and rapid test method.

2. oil painting inspection

Clean the surface of the outer covering with clean gauze. Then, apply clean brush evenly in the same direction to the whole outer surface of the stamping part. Put the finished stamping parts in strong light for inspection. It is recommended to put the stamping parts on the body position. It is easy to find the tiny pitting, flat pond and corrugated on the stamping parts by this method.

3. grinding of flexible yarn mesh

Clean the surface of the outer covering with clean gauze. Any pitting and indentation can be easily found by grinding the surface of the stamping piece to the whole surface along the longitudinal direction by using flexible sand mesh.

4. polishing of oilstone

(1) First, clean the surface of the outer covering with clean gauze, then polish the oilstone (20 × 20 × 100mm or larger), and polish the places with circular arc and difficult to contact with relatively small oilstone (for example: 8 × 100mm semicircular oilstone)

(2) The choice of the size of the oilstone depends on the surface conditions (such as roughness, galvanizing, etc.). Fine grained oilstone is recommended. The direction of the polishing of the oilstone is basically carried out along the longitudinal direction, and it is very suitable for the surface of the stamping parts. Some special places can also supplement the horizontal grinding.

5. visual inspection

Visual inspection is mainly used to find out the appearance abnormality and macro defect of stamping parts

6. inspection tools

Put the stamping parts into the inspection tool, and inspect the South skin stamping parts according to the operation requirements of the inspection tool instruction.