How to set CNC flame oxygen fuel cutting machine preheating speed

The preheat treatment of CNC flame oxygen fuel cutting machine is the most direct way to control the temperature of cutting flame. In the working mode of most CNC flame oxygen fuel cutting machine in China, the time design of the control system is generally needed to control the temperature of cutting flame. The traditional flame cutting method is combined with numerical control technology to make it possible to control the temperature of cutting flame. CNC flame oxygen fuel cutting machine has been widely applied in the market. In the actual processing and use, considering the great difference in the thickness of the flame cutting plate, many enterprises can not accurately grasp the speed settings of the NC flame cutting machine under different materials and thickness.

The cutting speed of the steel plate corresponds to the burning rate of the steel in oxygen. In the actual production of NC flame cutting machine, the cutting speed should be adjusted according to the performance parameters of the cutting nozzle, gas type and purity, steel plate material and thickness. Cutting speed directly affects the stability of cutting process and the quality of cutting section. If we want to artificially adjust the cutting speed to improve production efficiency and reduce the cutting speed to the best improve the quality of the section, that is impossible, can only make the quality of the cutting section worse. Excessive cutting speed will cause quality defects such as sag and slag hanging on the cutting section, which may seriously cause cutting terminal; too slow cutting speed will cause the upper edge of the incision to melt and collapse, lower edge to produce rounded corners, the lower half of the cutting section to appear water-punched deep grooves and so on.

By observing the characteristics of slag ejected from the incision of NC flame cutting machine, the cutting speed can be adjusted to a suitable one. In the normal flame cutting process, cutting oxygen flow relative to the vertical torch slightly behind an angle, the corresponding offset is called after the drag. When the speed is too low, there is a rear support quantity, and the spark beam below the workpiece is offset to the cutting direction. If the running speed of the cutting torch is increased, the spark beam will deviate in the opposite direction. When the spark beam is parallel to the cutting oxygen flow, the cutting speed is considered normal. When the velocity is too high, the spark deflected obviously.

The preheating speed setting operation of CNC flame oxygen fuel cutting machine summarizes the following six points for attention.

1. the power of the preheating and cutting flame (acetylene flow and oxygen flow) increases with the increase of the thickness of the steel plate.

2. When using diffuse nozzle and oxygen curtain nozzle to cut steel plate whose thickness is less than 20 mm, the flame power should be higher, so as to accelerate the incision leading edge heating to the burning point, so as to obtain a higher cutting speed.

3. When cutting thick steel plate, the flame should use mild carbonization flame to avoid the upper edge of the incision from melting down, and at the same time can make the outer flame longer.

4. When cutting groove with single cutting nozzle, slag is blown to the outside of the incision. In order to supplement heat, the power of the flame should be increased.

5. When CNC flame oxygen fuel cutting machine cutting steel with higher carbon content or alloy element content, the preheating flame power is higher because of its higher ignition point.

6. Using LPG or natural gas as fuel gas, because of its low flame temperature and long preheating time; cutting small-sized parts and other occasions that need frequent preheating and cutting, in order to improve cutting efficiency, the flame can be adjusted to oxidation flame, and then restored to neutral flame after cutting.