In the processing industry, I believe you are no stranger to metal stretch parts. For the processing of metal stretch parts, there is no shortage of metal stretch parts molds. However, many people always don't know how to start when facing the hardware drawing. In fact, the hardware drawing die needs the combination of theoretical calculation and practice in many cases. It is not so easy to do a good job of drawing dies, especially continuous drawing dies, which involves some professional design knowledge. How to overcome the mold processing of hardware stretching parts? It is suggested to start from the following aspects.

1. Learn how to unfold the stretched parts

There are two kinds of stretching parts: software stretching and manual stretching. For the expansion of general cylindrical parts, it is generally feasible to use software or manual development. For complex curved surface parts and irregular products, it can use software development, such as one-step expansion with UG software or AutoForm software. Its principle is based on the principle that the material does not change in volume without thinning.

Then the computer expansion is based on the finite element analysis and calculation to obtain an expansion result. Usually, this result is the result under ideal conditions and has great reference value. The use of manual expansion is to obtain an expanded radius through mathematical calculation, so manual expansion can only be a regular and mathematically calculable way.

2. Learn to calculate tensile parameters

The biggest problem perplexing us in tensile calculation is how many times a piece can be pulled out and how to determine the size of each time? The master who has done the drawing mold is usually confused about this. If you can calculate, it's like seeing the sun through the clouds. A very important parameter in the tensile parameters is the tensile coefficient m, which is simply a ratio and an empirical parameter summarized by predecessors in long-term practice. Tensile coefficient M = finished product size D / blank size D. when this coefficient is less than the ultimate tensile coefficient of a material, we evaluate that the product cannot be pulled out at one time, that is, there will be a risk of fracture. Of course, the drawing part also has a great relationship with the forming r of the product and the size of the blank holder. There are many parameters involved. For details, please consult the relevant drawing data for details.

3. Process layout

Process design is to calculate the drawing size according to the drawing calculation results, but the calculation of each drawing height is quite complex. In order to obtain the drawing height more intuitively and simply, we can use CAD software for simulation calculation and determine the correct height value of each drawing by adjusting the drawing height value several times. Here, we still follow the principle of constant volume. Of course, the calculation of written expression is a difficult process. It needs practical operation to really master it.

Finally, I want to tell you that stretching is not as difficult as you think. It's just the so-called meeting is not difficult, and the difficult won't. Find experienced people to learn methods, then many problems will be solved.