In the cutting field, plasma cutting, especially fine plasma cutting, has been applied in many industrial fields. However, with the development of optical fiber and other laser technologies, laser cutting machines have also begun to be favored by some users in recent years. So, plasma cutting and laser cutting, which cutting method is more suitable for the company's product production? We will let users discuss the advantages and disadvantages of the two cutting processes from the user's perspective, and design for the future purchase of cutting products and production processes Of engineers provide a reference.
Application of plasma cutting machine and laser cutting machine
The laser cutting machine is mainly used for medium and thin plates and is mainly used for the preparation of carbon steel and stainless steel plates with a thickness of less than 8mm, especially for parts with complex shapes and high cutting surface accuracy. In addition to cutting various high melting point materials, heat-resistant alloys, and super-hard alloys, and other special metal materials, laser cutting machines can also cut semiconductor materials, non-metallic materials, and composite materials. The laser has extremely high luminous intensity because of its almost non-divergent directivity. The laser cutting speed is fast, the processing accuracy is high, and the cutting seam is narrow. Compared with plasma cutting, the heat-affected zone is small, the cutting plate deformation is small, the cutting surface is not lifted, and subsequent processing is generally not required. The plasma cutting machine can be used for cutting various metal materials such as stainless steel, aluminum, copper, cast iron, carbon steel, etc. The thickness of the plate is generally 6-40mm. Taking 260A plasma cutting as an example, the maximum cutting thickness can reach 60mm. The plasma cutting speed is fast, the slit is narrow, the incision is flat, the operating cost is low, and it has significant energy saving and economic effects.
Working principle and characteristics of the plasma cutting machine and laser cutting machine
The working principle of plasma cutting is to use oxygen or nitrogen as the working gas, use the heat of the high-temperature plasma arc to locally melt and evaporate the metal at the incision of the workpiece, and use the momentum of the high-speed plasma flow to remove the molten metal to form a processing method. Plasma cutting is suitable for cutting various metal materials, mainly for medium and thick plates. The advantage is that the cutting speed is fast, the slit is narrow, the heat-affected zone is small, and the deformation is low; the disadvantage is that the verticality of the section has an inclination angle of 0.5°~1.5°, and the cut is hardened.
Laser cutting is a laser beam generated by a laser, transmitted through a series of mirrors, and finally focused by a focusing mirror to the surface of the workpiece, generating a local high temperature at the focal point, so that the heated point of the workpiece instantly melts or vaporizes into a slit. During the cutting process, auxiliary gas is added to finally achieve the purpose of processing the slag at the slit. Laser cutting is mainly based on medium and thin plates, and the range of cutting materials is very wide (metal, non-metal, ceramic, glass, etc.). Because the laser has the characteristics of high direction, high brightness, high intensity, etc., the laser cutting speed is fast, the processing accuracy is high, and the slit is very narrow. Generally, subsequent processing is not required.
In summary, in terms of cutting materials, laser cutting materials choose plasma cutting more widely; in thin plate cutting, laser cutting has more significant advantages; and in terms of cost, plasma cutting is much cheaper for laser cutting.
Advantages and disadvantages of laser cutting machine and plasma cutting machine
Compared with the general cutting method, the laser cutting machine has some significant advantages: ①The laser cutting has a small kerf, and the cutting surface can be directly used for welding without grinding. ②Laser cutting machine is fast: the speed of cutting a thin plate can reach 10m/min, which is much faster than that of the plasma cutting machine. ③The laser cutting machine has good cutting quality, small deformation, low surface roughness value, and small bevel. ④The laser cutting machine has high accuracy: the positioning accuracy can reach 0.05mm, and the repeat positioning accuracy can reach 0.02mm. ⑤Laser cutting machine cuts a wide range of materials: In addition to cutting metal, it can also cut a variety of materials such as wood, plastic, rubber, PVC, leather, textiles, and organic glass, with a wide range of applications.
Disadvantages of laser cutting: laser cutting costs are high, initial investment and later maintenance require higher costs. At present, lasers are more cost-effective in cutting thin plates, but they are low in efficiency when cutting medium and thick plates. Unless the quality requirements are high, it is not suitable to Use laser cutting.
Advantages of plasma cutting: In the process of cutting medium and thick plates, it can reach a very high cutting speed, which is much higher than that of laser and flame. The initial equipment investment is lower than the laser, and the later maintenance cost is also lower than the laser.
Disadvantages of plasma cutting: ①Poor verticality of the cutting surface: One side of the cutting surface will have a large bevel, and the verticality will be poor. ② Produce more cutting slag: During the cutting process, cutting slag will be generated below the cutting surface. In order not to affect the quality of the subsequent process, this cutting slag must be removed by grinding, which also increases labor costs. ③ Harmful gas and arc light will be generated: The principle of plasma cutting determines that harmful dust and arc light will be generated during the cutting process. However, there is also underwater plasma cutting to avoid this defect. ④The later cutting nozzle will consume more and cost more.
Comparison of laser cutting machine and plasma cutting machine
(1) The laser cutting machine will not damage the workpiece, but the plasma cutting machine has large or small damage to the plate, especially when the plasma cutting machine cutting gun and cutting nozzle have problems during the cutting process, it will cause obvious defects to the plate.
(2) Since the laser beam is focused into a small spot, the slit of the laser cutting machine is narrow, and the slit of the plasma cutting machine is slightly larger than that of the laser cutting machine.
(3) The laser cutting machine is fast: the cutting speed can reach 10m/min, which is much faster than that of the plasma cutting machine.
(4) The cutting surface of the laser cutting machine is smooth, no burrs, good cutting quality, non-contact cutting, the cutting edge is little affected by heat, and there is basically no thermal deformation of the workpiece, completely avoiding the collapse of the material when the material is punched, and the cutting seam is generally not Need secondary processing. However, the thickness of the cut sheet is limited and the processing cost is high. The plasma cutting machine can cut steel plates above 6-40mm according to different models and power sizes, and the processing cost is relatively low.
(5) The laser cutting machine has high precision: the positioning accuracy of the laser cutting machine is 0.05mm, and the repeated positioning accuracy is 0.02mm, but the working environment requires high. Although the processing accuracy of the plasma cutting machine is not better than that of the laser cutting machine, it has lower requirements for the working environment and stronger mobility and has a wider range of adaptation to cutting. The skill level of the personnel is lower than that of laser cutting.
In general, the advantages of laser cutting machines are higher cutting accuracy, faster speed, and less plate deformation, which is suitable for the preparation of parts with complex shapes. But for now, the cutting thickness is limited. Under normal circumstances, a single piece with high precision requirements is used for cutting the plate with a thickness of less than 8mm. The cutting cost is higher and the cleanliness of the plate is also required. The advantages of the plasma cutting machine are that it has a wide cutting area and can cut all metal plates; the cutting speed is fast and the efficiency is high; the cutting accuracy is higher than that of CNC flame cutting, and the precision of fine plasma cutting is higher. The disadvantage is that it is difficult to cut thick plates, especially steel plates above 20mm. It requires a high-power plasma power supply and the cost is higher (but still lower than the cost of a laser cutting machine).
