⑴The problem occurred. The surface quality requirements of Bare Engine are very strict. The pull marks on the cutting edge not only affect the surface quality, but also hang magnetism in some flaw detection processes.

In order to control this defect, the equipment has to be frequently stopped during production to disassemble and cut the edge mold.

Polishing and repairing the edge of the die not only affects the production efficiency, but also reduces the service life of the mold.

The forgings produced need to be polished and repaired, and the deep-drawn ones can only be scrapped, resulting in high production costs for MG Roewe Maxus Engine.

⑵Solution. The generation of cutting edge pull marks is mainly due to the special use environment of the cutting die, and the cutting edge is prone to tiny cracks.

When the cracks are sandwiched with oxide scale, scratches of different depths will be left on the forgings. Therefore, the problem is transformed into a method to solve the cracking of the cutting edge of the cutting die.

Practice has proved that after special treatment, the service life of the die has increased from about 4,000 pieces to more than 15,000 pieces, which greatly improves the cutting edge quality and production efficiency of Bare Engine and effectively controls the production cost.