The quality of gas cutting depends largely on the cutting mouth, that is, the wind line. Use small fire for thin plate, the cutting nozzle should be high from the plate, the inclination angle should be large, and the cutting speed should be fast. The purpose is to reduce deformation. For the thick plate with carbonization flame exceeding 30, the high-pressure wind is deformed by the wind pole, and the speed is slow and stable. Beginners want to listen to poof. Also note that the wind line is perpendicular to the board. It depends on whether acetylene or propane is used. Propane can be neutral and acetylene should be carbonized. Carbonization flame cannot be used for thick plates. Just cut more.