Views: 150 Author: Site Editor Publish Time: 2021-03-10 Origin: Site
To ensure that a technical agreement should be signed with the blank manufacturing unit. For precision molds and parts, quality. When selecting the blank data, pay attention to zero so that the deformation and direction of the relevant parts should be as consistent as possible. The drawing direction of the piece on the blank. Choosing the processing method can know that there are many types of mold processing methods, in the past content. And each processing method has its reasonable range of use. For the appearance shape, size range, material hardness, and economical precision of the processed parts, the personnel must select the best processing method based on various factors. Requirement such as degree of hardness, surface roughness, processing efficiency and cost. Arranging the processing sequence has a great effect on processing quality, production efficiency, and economic effects. Arrange the surface processing sequence of the parts reasonably. It is necessary to deal with the concentration, dispersion and influence of the process.
The proportion of die-casting molds in the precision mold parts processing industry will continue to increase. With the development of products such as vehicles and motors in the direction of lighter weight, higher and higher requirements will be put forward on the number, life and complexity of die-casting molds. With the development of replacing steel with plastic and wood with plastic and increasing precision and complexity of product parts, the proportion of plastic molds will continue to increase, and their precision and complexity will increase accordingly.
The steel includes profile (plate, bar) forgings, castings and welded parts. For precision molds and parts, profiles should be selected as far as possible according to the shape, size and data of the parts. When the blank size needs to be selected by factors such as type and technical requirements. In order to facilitate the processing of the blank. Forgings should be used. Large-scale parts are commonly used in castings, forging profiles or in order to improve the physical and mechanical properties of the materials. The size should be based on the machining allowance, the quality and accuracy of the rough appearance, and the shape of the processed rough should be similar to the shape of the part. The amount of clamping and the number of parts to be processed from a blank should be calculated before ensuring the quality of parts processing. The smallest blank size should be selected as much as possible. The appearance and internal quality of the blanks and the supply status (such as annealing, quenching and tempering, etc.) should be clearly defined when preparing the process. The surface decarburization layer, oxide skin, sandwiched skin, cracks, pits and other defects must meet the standard requirements. Annealing hardness of forgings shall not be greater than! For large-scale casting, forging and welding blanks, annealing should be carried out to eliminate internal stress.
my country's precision mold parts processing industry should further develop multi-functional composite molds. In addition to stamping and forming parts, a set of multi-functional molds also undertakes assembly tasks such as lamination, tapping, riveting and locking. Multi-color and multi-material plastic forming molds will also have rapid development. This kind of plastic mold shortens the production cycle of the product, and will be developed and applied in different fields in the future.
When arranging the processing sequence of precision molds and parts, the division of processing stages and the sequence of procedures are issues. The process is scattered and concentrated, and the parts are often polyhedrons composed of more complex shapes, because the molds are produced in a single piece of multiple varieties. As a result, there are many processing methods that use centralized processes, and the profile requires to ensure the mutual positional relationship. That is, some special tools and fixtures should be used as far as possible under the conditions allowed by the machine tool. This is especially true for large parts to make the workpiece complete the most processing in one clamping or one process. This is conducive to simplifying the process and production management. The division of the processing stage, such as the processing of fixed plates, templates, guide posts, guide sleeves, etc., and structural parts of the mold. It can be divided into four stages of general mechanical parts, such as die, punch, rough, semi-finished, finishing and finishing. And most of the working parts. It can be divided into rough machining, base surface machining, scribing, rough machining of working surface and profile, semi-finishing and finishing cores. Work, repair and finishing and other processes. Generally, it is the processing of hexahedron or cylinder, and the rough processing is to remove the rough appearance of the blank. For large-scale castings and forgings, the temporary waste processing steps are used to remove furs and find out whether there are defects on the surface of the blanks in time.
As my country's precision mold parts processing industry becomes larger and larger, the precision will become higher and higher. Ten years ago, the precision of precision molds was generally 5μm, and now it has reached 2-3μm. Soon, 1μm precision molds will be on the market. With the miniaturization of parts and the improvement of precision requirements, the machining accuracy tolerance of some precision mold parts is required to be below 1μm, which requires the development of ultra-precision machining.
As a processing benchmark for the next process. Generally, the base surface needs to be refined. Roughness! The value is not greater than the two opposite base surfaces of the hexagonal parts required to be parallel, milling, fine turning or fine grinding. And keep perpendicular to the adjacent two sides. It is often based on the base surface, and scribing is a commonly used procedure before parts are processed. Draw out all the dimension lines and center positions that need to be referred to during processing. Working surface and profile processing are based on the base surface and refer to the scribe line to process the parts into shape. The processing method is also divided into rough processing, semi-finishing and finishing. China's precision mold parts processing With the increasing application of hot runner technology, the proportion of hot runner molds in precision molds will gradually increase. Plastic molds using hot runner technology can improve the productivity and quality of the parts, and can also save the raw materials of the parts. The application of this technology is developing rapidly abroad. Domestic hot runner molds have also been produced, and some companies have reached about 30%, but in general, the proportion is still very low, and it is urgent to develop. To ensure that the surfaces of the parts meet the requirements of the drawings. The polished appearance should be left with a machining allowance. A method to reduce the processing requirements of machine tools. When the parts are prepared and repaired, it is for the convenience of mold manufacturing. Or when the final size must be determined through a trial mold, the relative position, matching size and clearance are required to be guaranteed. Usually, it is based on a certain part or a certain size, instead of directly processing the part to size according to the drawing. Use this for other parts to match or leave a correction amount on the parts to be corrected after assembly or mold trial. This method is processed by ordinary precision machine tools. But when machining parts with precision machine tools, it is widely used when machining parts. Precision molds and parts often adopt the basic dimensions without tolerance according to the drawings.