Classification

1. Cold stamping processes

The separation process is to separate cold stamping parts or blanks along certain contours.

The deformation process is to make the semi-finished material produce the new deformation and form the needed shape and size parts under the premise that the material does not produce the destruction.

2. Cold stamping can be divided into five basic processes: blanking, bending, drawing, forming, three-dimensional pressing.

3. The difference between blanking and punching; separating the plate along the closed contour; cutting the part is the blanking of the workpiece; cutting the part is the waste is punching.

4. Stamping process characteristics

1) High production efficiency, easy to operate, easy to automate.

2) Material utilization rate is high.

3) Dimensional stability, good interchangeability.

4) Practical wide

5) A wide range of manufacturing

6) The mold cycle is long, generally used for mass production of sheet metal.

5. Main technical parameters of 5 crank press.

1) Nominal pressure

2) Travel time of slide block

3) Slider per minute

4) The height of the press die

5) Press work table size

6) Leakage hole size

7) Die handle hole size

8) Press motor power

6. The difference between new moon and deformation resistance.

The new nature refers to the permanent deformation of metal materials under the action of external force, but not to be destroyed, and the deformation resistance refers to the ability of the metal to resist the deformation under the action of external force.

7. Work hardening; with the increase of deformation degree, the deformation resistance increase, the strength and hardness increase, while the ductility and toughness decrease.

8. The composition of blanking section;

Under normal blanking. The section consists of rounded bands, bright bands, fracture zones and burrs.

9. When the clearance is too small, the section will be sheared two times, forming the two bright band section, which consists of fillet, bright band, fracture zone, burr and bright band.

10. The influence of blanking clearance on dimension precision, blanking force and die life.

The smaller clearance is, the higher the dimension precision is, and the higher the clearance is, the higher the life of the die is.

The greater the clearance, the thicker the plate, the greater the punching force.

Blanking clearance refers to the difference of size, the working part of the double clearance between punch and die.

11. Measure to reduce blanking force and process requirements.

12. Heating blanking (only for thick high precision blanking. Oblique edge blanking, blanking should be rested on the concave die punching toughness do should be sitting in the punch on the oblique ligament). 3 steps blanking (mainly for a plurality of convex die and its position is the symmetry of the die).

13. The concept of edge and its influence factors. Layout between blanking and blanking (A) left behind the process strip. Material thickness, material type, size of blanking parts and contour shape of blanking parts.

14. Blanking die according to process combination, single process simple mold, multi process continuous die, compound die and continuous compound die.

15. Continuous die; refers to the press in a stroke, in several different position at the same time, the completion of the multi process stamping die.

Compound die; in a stroke of the press, in the same position, at the same time, the completion of several processes stamping die.

16. Main technical problems of hole die.

How to improve the strength and stiffness of the punch, the full length guide structure is used to protect the punch or the ultra short punch structure.

17. Two kinds of positioning methods and characteristics of continuous dies.

The continuous die with guide pin fixed distance, with the stopper pin to control the feeding step distance, neither lifting the strip nor the push and pull like the back belt or the retaining pin, can make the strip continuous feeding. Easy to use.

The continuous die with side blade fixed distance is not limited by blanking parts, and it is easy to operate, safe, high feeding speed and easy to realize automation. Complex structure, waste of materials. The fixed distance accuracy is lower than the guide pin, so some continuous dies are connected with the guide pin, the side blade is rough positioned, the guide pin is precisely positioned, and the length of the side blade section is slightly longer than the feeding step distance, so that the guide pin has a positive margin.