Design points of drawing die
- Material selection
In general, the raw materials of the stretched products are specified by the customer, but the same raw materials also have different models, such as cold-rolled sheets: 08Al.08.08F.10.15.20 steel, if the selection is improper, it may not be produced. Qualified product.
Second, open the blank
Generally speaking, most of the convoluted stretched products with simple rules and forms are stretched without thinning, which can be directly determined according to the principle of the product of the front and back sides of the stretch. Assuming that the shape of the tensile member is complex, and occasional tight flow may occur and become thinner, the size of the opening cannot be accurately calculated in general, and the three-dimensional opening is estimated, which is the so-called sample.
3. Tensile calculation coefficient
The tensile coefficient is very important. It needs to be stretched in several steps to ensure that there are no cracks, wrinkles and other problems that require the use of the tensile coefficient formula. This is one of the main parameters in the drawing process calculation and is often used to determine the drawing sequence and number of draws.
However, the tensile coefficient is not fixed, and there are many influences on the tensile coefficient, including: raw material type, thickness, and tensile structure type. The number of stretching, the stretching speed, the large arc of the stretching insert, etc. However, the average person can still consult the table to calculate.
Fourth, it is the problem of ordinary tensile test
During the drawing process, there are often phenomena such as drawing and wrinkling. If there is cracking, it is necessary to study the flow of raw materials. You may wish to apply lubricating oil on the die, not on the punch. Maybe when there is a 0.013-0.018mm film on the product side of the die, it is usually used. The fitter wraps the film.
There are more wrinkles and less cracks, which infers the flow state of the raw materials. Adjustment procedure: adjust the blank holder pressure, increase the drawing rib, change the arc radius of the upper and lower die inserts is too large, the workpiece mouth, etc. Generally speaking, drawing parts are molds with high technological content, whether it is design, processing, assembly or debugging…
Secondly, the design of the tensile parts should be conducive to the improvement of the utilization rate of metal materials, reduce the variety and specifications of materials, and reduce the consumption of materials as much as possible. Allows the use of inexpensive materials to make parts as scrap-free and as low-waste as possible. When designing the extension piece, when it is determined that it can be used normally, the requirements for dimensional accuracy grade and surface roughness should be reduced as much as possible, which is conducive to the interchangeability of products, reduces waste, and ensures stable product quality.
The tensile design requires simple shape and reasonable structure, which is conducive to simplifying the mold structure and simplifying the number of processes, that is, using fewer and simple drawing processes to complete the processing of all parts; less processing by other methods is also conducive to wire drawing operations. It is convenient for organizations to realize mechanized and automated production and improve labor productivity. Tensile parts are designed to meet the usage and technical performance of the product, and are easy to assemble and repair.
The above content is the design of the drawing die. For the general drawing process, simple dies, low melting point alloy dies, die sets, wire drawing manufacturing systems, etc. can be used to organize the drawing processing of multi-variety and small batch parts. Hope the above content is helpful to readers.