When processing metal materials by plasma cutting, to improve the processing quality and effect of plasma cutting, it is necessary to increase the speed of plasma cutting. We need to understand that not simply increasing the speed of the CNC plasma cutting machine can comprehensively improve the quality of the cutting process. At the same time, there is no complete proportional relationship between the cutting quality of the material and the plasma cutting speed. In other words, to understand, for CNC plasma The operation of the cutting machine, especially the speed control design, requires a suitable speed range control. Below we will put forward guidance and suggestions on this operation combined with some practical experience for the reference of the majority of users:
1. Model of plasma cutting machine power supply
This model is generally the output current of the plasma cutting machine power supply, such as 40A, 60A, 100A, 200A, etc. (Of course, some models of imported plasma such as German Kelly, American Haibao, and other brands are not based on the output current size, here I won’t go into details). Depending on the power of the model, the selected cutting current will be different, and the cutting speed will be different. The above data does not indicate what brand and model of plasma cutting power supply is selected, so it cannot be given. Detailed data.
2. The material of the plasma cutting workpiece is different
According to different cutting materials, the cutting speed is also different. Common cutting materials: carbon steel, stainless steel cutting speed is faster, cast iron is slightly slower, followed by aluminum, the slowest is copper because copper and aluminum are more difficult to cut, and the cutting speed The first two are much slower, and the cutting thickness of the same power CNC plasma cutting machine is much smaller than that of stainless steel and carbon steel when processing copper and aluminum.
3. The size of the input voltage of the plasma cutting site
The general factory power supply voltage is AC 380V, but due to the different conditions of each factory site, the general voltage fluctuates between 365V and 410V (of course, the difference is even greater in some places), so the input voltage is also a factor that affects the cutting speed. When the load rate of the power grid is too large, it may cause the power supply voltage to be too low, and also affect the cutting speed of the CNC plasma cutting machine.
4. working gas and flow
The working gas includes cutting gas and auxiliary gas. Some equipment also requires arc starting gas. Usually, suitable working gas should be selected according to the type of cutting material, thickness, and cutting method. The cutting gas must not only ensure the formation of the plasma jet but also ensure the removal of molten metal and oxides in the incision. Excessive gas flow will take away more arc heat, making the length of the jet shorter, resulting in reduced cutting ability and arc instability; too small gas flow will make the plasma arc lose its proper straightness and cause cutting As the depth becomes shallower, it is easy to produce dross; therefore, the gas flow rate must be well-matched with the cutting current and speed. Most of the current plasma arc cutting machines rely on gas pressure to control the flow, because when the torch aperture is constant, controlling the gas pressure also controls the flow. The gas pressure used to cut a certain thickness of the material is usually selected according to the data provided by the user. If there are other special applications, the gas pressure needs to be determined through actual cutting tests. The most commonly used working gases are argon, nitrogen, oxygen, air and H35, argon-nitrogen mixed gas, etc. Regarding the effects of various gases on plasma cutting, please refer to (What are the effects of the gases used by CNC plasma cutting machines).
The above three points are based on the parameter design requirements of the same model of CNC plasma cutting machine at the same cutting speed. Considering the selection of CNC plasma cutting machine equipment, although we cannot directly link the quality of the cutting process to the cutting speed of the equipment, we still need to focus on the speed range of the CNC plasma cutting machine.