First, learn to stretch the expansion
The expansion of the stretched parts can be divided into two types: software expansion and manual expansion. For the expansion of general cylindrical parts, it is generally feasible to use software and manual expansion. For complex curved parts, irregular products, Then we can use software to expand, for example: one-step expansion of UG software, or expansion with AUTOFORM software is possible. Its principle is to assume that the material does not change in volume without thinning. principle.
Then the computer expansion is based on the finite element analysis and calculation to obtain an expansion result, which is usually the result under ideal conditions and has a great reference value. Manual expansion is the radius of expansion obtained by mathematical calculation, so manual expansion can only be a conventional method of mathematical calculation.
2. Learn to calculate the stretching parameters
The biggest problem that troubles us in the stretching calculation is how many times a piece can be pulled out, and how to determine the size of each time? Masters who have done stretching molds are generally confused about this piece. If you can calculate, it will be like clearing the clouds and seeing the sun. A very important parameter in the stretching parameters is the stretching coefficient M, which is a ratio to put it bluntly, and is an empirical parameter summed up 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 certain material, then we assess that the product cannot be pulled out at one time, that is, there is a risk of rupture. Of course, the stretched parts are also closely related to the forming R of the product and the size of the blank holder. There are many parameters involved. For details, you can consult the relevant stretching data for details.
3. Process layout
The process design is to calculate the stretched size according to the result of the stretching calculation, but the calculation is quite complicated each time the height is stretched. In order to obtain the stretched height more intuitively and easily, the CAD software can be used for simulation calculation. Adjust the height value of the stretch a few times to determine the correct height value for each stretch, still following the principle of constant volume. Of course, expressing computation in words is a difficult process. It takes practice to really master it.
The last thing I want to tell you is that stretching is not as difficult as you think. Find experienced people to learn the method, then many problems will be solved easily.
The above is the relevant content about the calculation of mold processing for metal drawing parts. For those who are not familiar with the field, mold processing is more complicated, and the failure rate is high. People in the industry can be said to be at their fingertips. Hope the above content is helpful to readersRead More →