Brief explanation of processes
Material is set to the parts former as shown.
The material is uncoiled, pulled toward the white arrow, straightened, and fed into the parts former.
The material fed to the parts former is cut into the specified size in the parts former.
This picture shows the inside of the parts former. This machine rolls in the material.
At the very backside is the cutting machine. The material is cut into the specified size here.
First to fifth stages of cold forging molds are put in line, punch on the left, die on the right.
The five punches move simultaneously producing one finished part per cycle. It is difficult to see the details from this picture, but the parts carrier is interlocked with the operation of the machine. The parts carrier, or "transfer", feeds the parts one by one to the following stages.
After completing the 5th stage, the part is discharged from the parts former.
As shown here, the parts former manufactures the part per cycle. 5 processes are performed while transferring the parts in one machine. If we did not have such a parts former, we would need to make 5 separate machines.
The operation of the parts former is extremely fast, turning out one part per second. This reduced processing time tremendously.
As shown above, the punch moves to roll the part.
The arms at the front side of the dies in the right picture are called "Transfer" which carry the parts to the next stages.
The transfer moves when punch and die move back to the left and right so that the parts can be transferred to the next stage smoothly.
Images of forming performed in the parts former
Note: Yellow, green, and blue portions are the "molds" for forming.
|Cutting||1st stage||2nd stage||3rd stage||4th stage||5th stage||completed|
Material fed into the machine is cut into a specified length.
It is formed to the target shape after going through 5 stages of the forging process.
What is important is to gain experiences and try to investigate
- Process analysis
As I explained under curing process, excessive deformation of metal will result in too much rigidity and cracking.
Therefore, in order to shape the metal into the target shape, it is very important to determine the level of deformation (forming) and the location of such deformation.
This is done through process analysis.
- Material development
For easier forming, it is extremely important to select the appropriate type of material.
First, determine the types of material which are able to satisfy the rigidity and durability requirements.
Determine the size of material through process analysis.
Determine the hardness of material from the required level of forming at each stage. Sometimes, it is easy to achieve the target shape with hard materials.
All the materials used at KYORITSU aree specially developed in collaboration with our material makers.
- Die design
Determine mold structure and material based on the required force (forming load) to form the target shape and the shape at each stage determined through process analysis.
As we explained in the cold forging mold, molds are heated up by forming.
Considering the heat deformation, the molds are made very precisely with tolerance on the order of 1 microni1/1000mmj.
In addition to the coating, the surfaces of molds are polished as smooth as mirrors. This reduces the friction caused by the material.