Process development and production of forging die parts

The projection area of this part is 950cm 2, any two pieces overlap, the teeth are not more than 0.1mm wrong, the whole circle is divided into 12 pieces, each piece has 11 grooves, a total of 132 grooves, the burr of the punching piece is not more than 0.05mm, the flatness is not more than 0.10mm, the parts are made of The material is cold-rolled electrical steel sheet of 0.5mm thickness. The material used for the part is cold-rolled electrical steel with a thickness of 0.5mm. The grade is DW360-50, and the requirements of the part and the product are analyzed.

　　Mold structure through the analysis of the part and product requirements, such a large stamping parts area, to achieve a flatness of not more than 0.10mm, if the mold does not use a special structure and high precision requirements of the mold parts, such precision product parts is difficult to meet the requirements. Therefore the shown die is designed. This die is a positive-loading lower ejector drop die, which is characterized by a guiding mechanism using 4 guide columns for rolling guidance, thus ensuring the guiding accuracy of the die. 4 sets of limit devices are set in the die to prevent the press from losing control and damaging the die, which plays a safety protection role for the die. During the stamping process, the stamping material is always in the state of compressive stress in the up and down direction, so that the parts are always in a relatively flat state. From the structural analysis, this die is composed of upper and lower parts: ① the lower die part is composed of lower die holder 1, concave die fixing plate 2, concave die plate 3, lower top material plate 11; ② the upper die part is composed of upper unloading plate 4, convex die 6, upper pad plate 7, upper die holder 8. Due to the large die, the upper and lower die parts are fixed with the press using pressure plate, so as to ensure the safety of die clamping.

　　In this die, during the punching process, when the press ram goes down, the ram goes down together with the upper die part, and the convex die 6 and concave die 3 separate the stamping material for punching, while the convex die and the lower top material plate 11 act on the stamping material during the downward movement of the press due to the counteraction with the lower top material plate in the polyurethane rubber 12, so that the stamping material is always in the stress state of two-way compressive stress during the punching process, thus restrains the blanking deformation of the stamping material, so that the flatness of the stamped out product parts meets the product requirements.

　　Design and processing of die parts (1) Due to the large size and thin thickness of the material stamped in this die, and considering the life of the die, the blanking clearance is 12% to 14% of the thickness of the stamped material.

　　(2) Design of convex die parts.

　　Due to the high dimensional accuracy of the die parts, the size of the convex die parts is large, and it is difficult to achieve the existing conditions by wire cutting overall processing, and even if it can be achieved, the parts are easier to be deformed, so I designed the parts into the insert structure. This not only solves the machining problem, but also reduces the deformation of the part by drilling a process hole in the blank material and making a closed cut, thus ensuring the accuracy of the molded part.

　　Because the shape of this part is more complex, so that the mold concave mold parts are also correspondingly complex, in order to facilitate processing, so that the processed parts are easy to meet the design requirements, also adopted the form of insert structure, it is composed of 16 pieces of inserts, each concave mold block using wire cutting processing and grinding processing, each piece of inserts with pins and screws fixed in the lower mold fixed plate (item 2), due to the good machining accuracy of each part, so the block After assembling, the design requirements are met, and the punching gap is evenly matched with the convex die block, and the size and burr of the stamped parts meet the requirements of the product parts after die testing.

　　Concave die block4 ConclusionThe stator fan-shaped piece mold, due to reasonable design and high machining accuracy, has reached the design requirements in one mold test after assembly, and the punched parts fully meet the requirements of the drawings. At present, this mold is running normally and brings good benefits to the users.