The correct method of flame adjustment for nc flame cutting machine

CNC flame cutting machines are mainly divided into early manual cutting and semi-automatic cutting machines, profiling cutting machines and CNC cutting machines. With the progress of society and the development of science and technology, they are more and more advanced and their cutting functions are more and more powerful. The general model structure mainly includes: manual; Profiling cutting machine, portable CNC cutting machine, cantilever CNC cutting machine, gantry CNC cutting machine, desktop CNC cutting machine and intersection line CNC cutting machine specially used for steel pipe intersection line cutting, all of the above structures can be cut by flame cutting. According to the thickness of metal materials and cutting metal, from the perspective of process, it is generally recommended to use flame to cut carbon steel plates with a diameter of more than 5 mm, because the thermal deformation of such steel plates is very small. Stainless steel and nonferrous metals cannot be cut with flame, because the stainless steel will produce high-density oxide layer on the surface after being heated, which will prevent the downward transfer of heat, thus affecting the plate.
The flame control cutting machine is fused; The heat dissipation capacity of non-ferrous metals such as copper and aluminum is very strong, which leads to the rapid loss of heat on the cutting surface, and the numerical control flame cutting machine also affects the fusing of plates. How to adjust the flame of the flame cutting machine Generally speaking, when using the flame cutting method, three cutting flames can be obtained by adjusting the proportion of oxygen and acetylene: neutral flame (i.e. normal flame), oxidation flame and reduction flame. The feature of normal flame is that there is no free oxygen and active carbon in its reduction zone, and there are three obvious areas, and the flame core has a distinct contour (close to a cylinder). The flame core is composed of acetylene and oxygen, and its end is a uniform round and bright shell. The shell consists of red hot carbon particles. The temperature of the flame core reaches 1000 ℃. The reduction zone is outside the flame core, which is obviously different from the flame core because of its dark brightness. The reduction zone is composed of carbon oxide and hydrogen, the products of incomplete combustion of acetylene. The temperature of the reduction zone can reach about 3000 ℃. The outer flame is the complete combustion zone, which is located outside the reduction zone. It is composed of carbon dioxide, water vapor and nitrogen. Its temperature varies from 1200 ℃ to 2500 ℃.
The oxidation flame is generated under the condition of excess oxygen. Its flame core is conical, its length is significantly shortened, its contour is unclear, and its brightness is dim; Similarly, the reduction zone and external flame are also shortened, and the flame is purple blue, accompanied by noise during combustion. The noise is related to the pressure of oxygen, and the temperature of the oxidation flame is higher than that of the normal flame. If the oxide flame is used for cutting, the cutting quality will be obviously deteriorated. The reduction flame is generated in the case of excess acetylene. The flame core has no obvious contour, and the end of the flame core has a green edge. The excess acetylene is judged according to the green edge; The reduction zone is unusually bright, almost mixing with the flame core; The outer flame is yellow. When there is too much acetylene, it starts to emit black smoke, which is caused by the lack of necessary oxygen for acetylene combustion in the flame. The energy of preheating flame is closely related to cutting speed and cutting quality. With the increase of the thickness of the workpiece to be cut and the acceleration of the cutting speed, the energy of the flame should also be increased, but it should not be too strong. Especially when cutting thick plates, the reaction heat generated by the metal combustion increases. The CNC flame cutting machine has strengthened the preheating ability of the front edge of the cutting point. At this time, the excessive preheating flame will cause the upper edge of the incision to seriously melt and collapse. If the preheating flame is too weak, the steel plate will not get enough energy, which will force the cutting speed to be reduced, or even interrupt the cutting process. Therefore, the relationship between the strength of preheating flame and cutting speed is mutually restrictive. Generally speaking, better cutting quality can be obtained by using neutral flame to cut steel plates below 200MM. When cutting thick steel plates, the reducing flame shall be used for preheating and cutting, because the flame of the reducing flame is relatively long, and the length of the flame shall be at least 1.2 times of the plate thickness.