Flame cutting flame cutting adjustment method
Flame cutting machine how to fire? When you are using flame cutting, can be obtained by adjusting the ratio of oxygen and acetylene cutting flame three: neutral flame (that is, Chang Yan), oxidizing atmosphere, reducing flame. Normal flame characteristics of NC flame cutting machine is restored without free oxygen and carbon, cutting flame cutting machine has three distinct areas, distinct flame core profile (near cylindrical). Flame core composed of acetylene and oxygen, and its tip is evenly rounded and polished shell. Shell made from hot carbon particles. Flame core temperature up to 1000 ° c. Restore areas outside the flame core, and flame brightness of the core difference is that it is dark. Restore the area by the products of incomplete combustion of acetylene--carbon dioxide and hydrogen, reducing temperatures of up to 3,000 degrees Celsius. Outer flame burns district, is located in the restored area, it is composed of carbon dioxide and water vapor, nitrogen, and temperatures vary between 1200~2500℃.
In oxidizing atmosphere is generated in case of excess oxygen, the conical flame core, shortened significantly in length, contour is also unclear, brightness Dim; Similarly, reduction zone and outer flame is also shortened, flames are purple-blue, burn with sound, sound pressure with oxygen, oxidizing atmosphere temperature is higher than a normal flame. If the cut used in oxidizing atmosphere, will worsen the cutting quality.
Reducing flame is returned in case of excess of acetylene, the flame core with no obvious contour, the flame core end of the edge of the Green, in accordance with this Green edge to determine if an excess of acetylene; restore the region's bright, almost flame mixed core as a whole; outer flame yellow. When acetylene surplus is too much, start black smoke, this is because acetylene burning in the flames caused by the lack of essential oxygen.
Preheat flame cutting speed and energy, close relation between cutting quality. Along with being cut increases the thickness of the workpiece and the cutting speed of flame energies should be enhanced, but not too strong, especially when cutting thick plates, combustion increases the heat of reaction of metals, preheating of the cutting edge capabilities have been strengthened, and excessive Preheat flame to melt the cut edge on serious collapse. Preheat flame too weak, will make the plates do not have access to adequate energy, forced to reduce speed, or even interrupt the cutting process. So Preheat flame cutting speed and strength of the relationship are mutually dependent.
If cutting 200MM steel plate, with a neutral flame can get better cutting quality. Restore should be used when cutting thick steel plate Preheat flame cutting, because reducing flame flame is long and flame length should be at least 1.2 times more than its thickness.