The characteristic of the flame of the gantry CNC plasma and flame cutting machine is that there is no free oxygen and activated carbon in its reduction zone, there are three distinct zones, and the flame core has a distinct outline (close to a cylindrical shape). The composition of the flame core is acetylene and oxygen, and its ends are uniformly rounded and brightly coated. The outer shell consists of red-hot carbon particles. 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 that its brightness is darker. The reduction zone is composed of carbon oxide and hydrogen, the products of incomplete combustion of acetylene, and 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, and its temperature varies between 1200 and 2500 °C.

The oxidizing flame of the gantry CNC plasma and flame cutting machine is generated in the case of excess oxygen. The flame core is conical, the length is obviously shortened, the outline is not clear, and the brightness is dim; similarly, the reduction zone and the outer flame are also When shortened, the flame is purple-blue, and there is a noise when burning. The size of the noise is related to the pressure of oxygen, and the temperature of the oxidizing flame is higher than that of the normal flame. Cutting with an oxidizing flame will significantly deteriorate the cut quality.

The reducing flame is generated in the case of excess acetylene, the flame core has no obvious outline, and the end of the flame core has a green edge. According to this green edge, it is judged that there is excess acetylene; the reduction zone is abnormally bright, almost the same as The flame core is mixed together; the outer flame is yellow. When there is too much acetylene in excess, black smoke begins to appear, which is caused by the lack of oxygen necessary for acetylene to burn in the flame.

The energy of the preheating flame of the gantry CNC flame cutting machine is closely related to the cutting speed and the quality of the incision. As the thickness of the workpiece to be cut increases and the cutting speed increases, the energy of the flame should also increase, but it should not be too strong. Especially when cutting thick plates, the reaction heat generated by the metal combustion of the gantry cutting machine increases. The preheating ability of the front edge of the cutting point is strengthened. At this time, an excessively strong preheating flame will seriously melt the upper edge of the incision and collapse. If the preheating flame is too weak, the steel plate will not get enough energy, which will reduce the cutting speed and even cause the cutting process to be interrupted. Therefore, the relationship between the strength of the preheating flame and the cutting speed is mutually restricted.

Generally speaking, the use of neutral flame for cutting steel plates below 200mm can achieve better cutting quality. When cutting large-thickness steel plates, the reducing flame should be used for preheating cutting, because the flame of the reducing flame is relatively long, and the length of the flame of the gantry CNC plasma and flame cutting machine should be at least 1.2 times the thickness of the plate.