Drawing blanking and punching compound die with fl

Compound die for drawing, blanking and punching with floating punch

for stretched parts, people are used to pre cutting or punching the sheet to a certain shape before stretching. For flange stretching parts with irregular flanges, the trimming process must be added after stretching to ensure the shape of the workpiece. If the workpiece has flatness requirements, the shaping process must be added, which increases the number of processes. The positioning error caused by the large number of processes may affect the quality of products, and this design method can not prevent hands from entering the dangerous area of the die, which is unsafe

1 process analysis

2 mold structure and working process

3 design of polyurethane rubber block

when designing the overall dimension of polyurethane rubber block, the pre compression shrinkage shall be selected first ε 1 = 5%, final compression ε 2 = 20%, and then calculate the rubber, so the design of the fixture is relatively simple. Then calculate the compression force of the rubber according to the relevant charts and data provided by the rubber factory. Finally, compare it with the forming force of the workpiece. If the two are not very close, reselect ε 1 and ε 2. Until the two are close

strictly speaking, the calculation of workpiece forming force and rubber compression force is not too accurate. In practical application, it is also necessary to adjust the rubber compression force by adjusting the rubber height based on the calculation, which is late in the domestic research on metal rubber materials

at the same time, polyurethane rubber has fine tissue and no bubbles and voids inside, so its volume can be considered incompressible. Therefore, the placement space of polyurethane rubber block should be calculated according to the principle of constant volume

4 design of punch and die

when the workpiece is formed with a shallow cone, the material here is subject to tensile stress in both tangential and radial directions, so that the workpiece is formed close to the punch, while the concave part only participates in the forming of the fillet r3mm. Therefore, 1. Regularly check whether the connecting line of the rear panel of the controller is in good contact with the shape of the forming part of the punch and die, as shown in Figure 3. This not only does not affect the forming, but also facilitates the metal flow during forming, reduces the forming force, and improves the strength of the punch and die

in addition, the height h is designed to be 4 ~ 6mm higher than the shallow conical table, so that the forming height will not be affected after the grinding of the punch and die

5 other key parts

h7/H6 sliding fit is adopted between the drawing punch and the fixed plate, and the fixed plate is quenched and tempered. The tensile blank holder force is adjusted by four plugs 3: according to the use of the machine and the service life of the oil, the roughness value of the working surface of the blank holder block 5 and the punch and concave die 10 is required to be low to avoid indentation on the surface of the workpiece