The cutting effect of the CNC flame cutting machine depends largely on the mastery of the adjustment technology. The cutting gas used in the CNC flame cutting machine is different, when cutting carbon plates of different thicknesses, the flame temperature should also be controlled to consider the cutting speed.
The CNC flame cutting machine can obtain different cutting flames according to different adjustment methods, so as to obtain different cutting effects. By adjusting the ratio of oxygen to acetylene, it is usually divided into three kinds of flames: normal flame, oxidation flame and reduction flame. The cutting flame characteristics of these three types are different. Generally, cutting 200 mm or smaller steel plates can get better cutting quality with ordinary flame. When cutting large-thickness steel plates, since the flame of the reduction flame is relatively long, the reduction flame should be preheated and cut, and the length of the flame should be at least 1.2 times the thickness of the steel plate.
One, normal flame
Conventional Fire Conditioning Technology Conventional flames are characterized by the absence of free oxygen and activated carbon in the reducing zone. There are three distinct regions, and the flame core is clearly defined close to the cylinder. The composition of the flame core is acetylene and oxygen, and its ends are uniformly round and shiny. The shell consists of red hot carbon dots. The temperature of the flame core reaches 1000°C. The reduction zone is outside the flame core, and the obvious difference from the flame core is its darkness. The reduction zone consists of carbon monoxide and hydrogen that have not been completely burned by acetylene, and the temperature in the reduction zone can reach about 3000°C. The outer flame is the complete combustion zone, located outside the reducing zone. It consists of carbon dioxide and water vapour, nitrogen, and varies in temperature between 1200 and 2500 °C.
The neutral flame we are talking about here is the state of a normal CNC cutting machine, but in actual operation, the success of adjustment is only the final result. In fact, the probability of oxidizing and reducing flames is still relatively high.
2. Oxidation flame
Oxidizer flames can be produced in the presence of excess oxygen. The flame core is conical, the length is obviously shortened, the outline is not clear, and the brightness is dim. Likewise, the reduction zone and the outer flame are shortened and the flame is purplish blue. The sound accompanies the sound, and the sound is related to the pressure of oxygen. The temperature of an oxidizing flame is higher than that of a normal flame. If oxidized flame cutting is used, the cutting quality will be greatly reduced.
Third, restore the flame
When acetylene is excessive, a reduction flame will be produced. The flame core has no obvious outline, and the end of the flame core has a green edge, and the excess acetylene is judged according to the green edge. The reduction area is unusually bright, almost a flame. The flames outside are yellow. With too much acetylene, it starts to smoke because the flame lacks the necessary oxygen for the acetylene to burn.
The energy of the preheating flame seriously affects the cutting speed and cutting quality. The preheating flame is too weak to make the steel plate obtain enough energy, and the cutting speed is forced to be reduced, and even the cutting process is interrupted; the preheating flame is too strong, the reaction heat generated by the metal combustion increases, and the preheating of the leading edge of the cutting edge Increased capacity can cause severe melting and collapse of the upper edge of the gap, especially when cutting thick plates. The preheating flame intensity and cutting speed are mutually limited in this system. As the thickness of the workpiece to be cut increases and the cutting speed increases, the energy of the flame should also increase with the thickness of the sheet.