The traditional processing method of the sheet metal workshop is to adopt the technological process of shearing, punching and bending. Among them, the blanking process requires a large number of molds, and the blanking in the sheet metal workshop has the characteristics of less cutting and no cutting, which is very important. In this way, dozens of sets are usually required during the processing of a product. Some products may require hundreds of molds. In terms of time, the mold itself needs a certain design and manufacturing cycle, and the product has a certain trial production cycle, which causes a lot of time delay. From an economic point of view, with a large number of molds, the cost of the product will increase accordingly, resulting in a waste of cost. Therefore, in the highly competitive environment of the entire market, a new processing method is urgently needed to replace it.

Based on the above reasons, laser processing technology emerged in the sheet metal workshop. The biggest feature of laser processing technology is that it does not require molds. The use of laser processing and blanking saves a large number of molds, shortens production time and product costs, and better gains advantages in the market. It is very conducive to the production of a variety of small batches of products, and subsequent mass production.

Features and advantages of laser processing technology

The laser is a coherent light source with high brightness, accurate directivity, monochromaticity and parallelism of the laser beam, and has a very high energy density. When focused, the laser beam can generate high temperatures on the irradiated material. Under the action of tens of thousands of degrees of high temperature, no matter how hard the material is, it will instantly melt and evaporate, and at the same time, a shock wave will be generated to melt and remove the material. In the process of laser material processing, it essentially causes local heating and melting to form vaporized material.

Laser processing technology can process parts that are difficult to achieve with traditional methods. For example, for large steel parts of the box, many holes of different sizes need to be processed, which cannot be achieved by traditional processing methods. Laser processing technology can meet these requirements. Compared with traditional processing methods, laser processing technology has the advantages of high accuracy and short time even if the same parts are processed, so that products have strong market competitiveness.

Laser processing has strong flexibility in a two-dimensional plane. When the laser cutting machine is used, the workpiece does not move, and the cutting machine is in a moving state, which will not leave dead corners for processing, so that the utilization rate of processing materials is correspondingly improved. The laser processing equipment is controlled by a computer. Set the mold and design the processing route, and then the corresponding processing can be carried out. Therefore, the process preparation time of laser processing technology can be greatly reduced. The laser processing equipment has a fast processing speed, which shortens the processing time and improves the production efficiency.

Laser processing technology in sheet metal workshop

1. Laser cutting technology

Laser cutting adopts CO2 laser or YAC laser to perform two-dimensional and three-dimensional cutting processing, which has the characteristics of high cutting precision. The laser source power varies from 5W to 90kW. There are series of products from 5W to 90kW. The laser cutting of sheet metal parts mainly uses a power laser of 100W to 1500W. When the output power of the laser source is less than 1500W, the laser source is in a single-mode oscillation mode and can be cut with a width of 0.2mm, which is clean and flat after cutting with power. When the output power of the laser source is greater than 1500w, the laser source is in a multi-mode oscillation mode and can be cut with a width of 1 mm, but there will be a small amount of dirt after cutting with the power. When cutting thick plates, auxiliary gases are required. The auxiliary gases include air, oxygen, and nitrogen. Nitrogen can prevent oxidation of the cut surface during the cutting process. Oxygen is suitable for high-speed cutting of thick plates.

When laser cutting, CAD or CAM technology can be used to provide processing information and processing parameters for the processed workpiece model and laser, which can quickly and accurately complete production and realize automated cutting.

2. Laser welding technology

Laser welding can be divided into pulse welding and high-power continuous welding. Laser welding can obtain high-density energy from a laser source for a single weld. The high-speed welding makes the welding seam less affected by heat and deformation, the welded joint has high quality, and the weld size of laser welding can be controlled. In laser welding, when matched with the same power, speed and lens, the focal plane of the laser lens and the position of the welding material can affect the heating efficiency of the material. Usually, the welding material should be higher than the focal plane of the laser lens.

Laser welding in the sheet metal workshop can be used to weld the plates of iron, stainless steel, aluminum, copper and titanium with a thickness of 0.1mm to 10mm. In the butt welding and full-position welding of thick plates, a mixed welding method of MIG and TIG should be used. At this time, the technicians in the sheet metal workshop should work with The technical staff in the customer unit cooperates closely.

3. Laser drilling technology

Laser drilling technology is the earliest practical laser technology in laser material processing technology. Laser drilling in the sheet metal workshop generally uses pulsed lasers, which have a high energy density and a short time. It is especially suitable for processing small holes with a certain angle and thin materials.

The laser can realize the drilling of the combustor parts of the gas turbine, and can realize the drilling effect in the three-dimensional direction, and the number can reach thousands. Perforated materials include stainless steel, nickel-chromium-iron alloys, and HASTELLOY-based alloys. The laser drilling technology is not affected by the mechanical properties of the material, and it is easier to realize automation.

4. Laser forming technology

The laser forming technology in the sheet metal workshop includes laser shock forming technology and laser bending forming technology. It can process curved plates, hemispheres, spheres, and parts with special-shaped cross-sections, and can also process convex and concave shapes on complex pipes.

The laser shock forming technology uses a laser source to irradiate the cladding of the sheet metal, and the cladding of the sheet metal is heated to produce plastic deformation. The laser bending forming technology uses a laser source to irradiate the parts of the workpiece that need to be bent. If the heated sheet metal parts are rapidly cooled, the sheet metal parts will be bent and deformed. Laser bending forming technology is especially used in the mass production of sheet metal parts bending and forming.

Conclusion

As a new technology, laser processing technology is the product of modern scientific development. Laser cutting technology, laser welding technology, laser drilling technology and laser forming technology also require skilled technicians in the production and processing of sheet metal workshops. With the development of laser material processing technology, the production and processing of sheet metal workshops will inevitably achieve a degree of stability, reliability, efficiency and high automation.