Servo Stamping Press And Application Example

​Although the development of stamping processing technology has been focused on molds so far, under the current globalization of production plants, it has fallen into the bottleneck of commercial expansion. The lack of local mold technicians overseas has become a problem that cannot be ignored.

If you can make good use of the punching curve of the servo punch, you will be able to use a simpler die to achieve a high degree of stamping, and you can more smoothly deepen the global strategy based on Industry 4.0 technology.

How to use servo punch
The biggest feature of the servo punch is that it can control the movement and speed of the punch, and use the most suitable punching curve to achieve the maximum production efficiency according to different processing purposes. However, it is not easy to make the most suitable stamping curve, how to find this most suitable stamping curve.

In order to find the best punching curve, we first divide the purpose of the punch action into two parts.
1. The punch action directly related to the forming process
This is the action of direct contact between the mold and the material, applying force and forming. The purpose of this action is to shorten the project, improve the molding effect, improve the processing accuracy, extend the life of the mold, and reduce the processing noise. The purpose is quite diverse.

2. The punch action not directly related to the forming process
The connection between the movement cycles of the punch before the die contacts the material or after the forming is completed. The purpose of the design of the punch action curve is to increase the capacity of the production line.

The optimization of the punch action in the second point above is not directly related to the actual forming process, so it should belong to the field of punch manufacturers. As for how much capacity can be increased, a considerable part depends on the performance of the press and automation equipment. Because the steps of designing the punch motion curve of each manufacturer are different, so consult the manufacturer of the punch press you are using for advice, and you should get the best results.

The optimization of the punch action in point 1 above is the most anticipated effect of the servo punch. However, to achieve this point, the actual product shape, material properties, engineering design, equipment performance and other factors will be intertwined. Interaction, systematic research on this aspect has not yet been published.

The punch movement patterns and their expected effects are organized as follows:
1. Low speed machining curve
This is the curve for processing with reduced punch speed. This is also a representative function of servo punch.
Its expected effect is:

• Reduce vibration and noise during cutting
• Reduces heat and mold wear during processing
• Improve molding effect
• Increase the stability of product accuracy
• Extend mold life

2. Holding pressure curve
This is a curve that stops the punch for a while and continues to pressurize.
Its expected effect is:

• Improve mold shape transferability. Especially suitable for difficult-to-form materials such as aluminum alloy and high-tensile steel plate.

3. Multi-section vibration curve
This is a curve that pressurizes the punch while shaking it up and down quickly. There is also a step curve where the punch does not pull up.
Its expected effect is:

• Suppression of workpiece thickness variation during drawing processing and prevention of wrinkling and cracking of the workpiece.
• Smooth flow of processed lubricants, thereby reducing the amount of lubricants used.
• Reduces heat and mold wear during processing
• Improve the cross-sectional quality of the blanking process.

4. Embossing curve
This is the curve of multiple back pressures in the forging section. The most common case is to use this curve at the bottom dead center.
Its expected effect is:

• Improve the shape transferability of the forged part, suitable for difficult-to-form materials such as ultra-high-tensile steel plates with large springback and unstable forming accuracy.

Reference: phdbooks.com