Lighter flame size automatic adjustment machines in the process of gas cutting, if the operator needs to move his body position, he should first close the oxygen making door and then move his body position. If a thinner plate is cut, the flame shall leave the steel plate surface quickly while closing the cutting oxygen, so as to prevent the deformation and re bonding of the harmful joint caused by the rapid heating of the thin plate. When you continue cutting, you must preheat the cutting part of the dimension, and then slowly open the oxygen cutting gas valve to continue cutting. When the cutting is close to the end point, the cutting shall be inclined to the opposite direction of cutting, so as to facilitate the lower part of the steel plate to be cut in advance and make the ending awning more neat. When the end point is reached, quickly close the cutting oxygen valve and lift the cutting torch, then close the acetylene valve, and finally close the preheating oxygen valve…