Shooting suction cutting torch

Cutting gunsUsage
First, unscrew the acetylene gas switch, and slightly unscrew the oxygen switch. After ignition, adjust the oxygen supply to make the oxyacetylene flame become a neutral flame (that is, the amount of acetylene and oxygen is appropriate). When cutting, first use this oxyacetylene flame to burn a certain point that is ready to be cut until it turns red hot. Then turn on the high-pressure pure oxygen flow switch to vigorously burn and melt the metal into a liquid in the oxygen flow, rinse it off, and then move the cutting gun along the line to be cut, cutting off the metal. When cutting, there are requirements for the inclination angle of the cutting gun, cutting speed, and oxygen pressure. The inclination of the cutting gun is mainly related to the thickness of the workpiece. When cutting steel plates with a thickness of 5-20mm, the cutting gun should be perpendicular to the workpiece and does not need to be tilted. The straight the cutting gun, the better the cutting quality, and the smaller the cutting seam. When cutting workpieces with a thickness less than 5mm, they can be tilted forward for cutting. If cutting workpieces with a thickness exceeding 30mm, the cutting gun should be tilted backwards for cutting. After cutting through, move the cutting gun while gradually turning it perpendicular to the workpiece for cutting. When the cutting is almost complete, tilt the cutting gun slightly inward until it is finished. The speed of cutting depends on the thickness of the workpiece. The thinner the workpiece, the faster it is, and vice versa, it should be slower. The pressure of supplying high-pressure oxygen gas flow is also related to the thickness of the cutting workpiece. If the oxygen supply is insufficient, it cannot be cut through; And if the pressure is too high, it will cause waste of oxygen. When cutting is completed, first turn off the high-pressure oxygen flow switch, then turn off the acetylene gas switch, and after blowing out the oxyacetylene flame, turn off the oxygen switch.

Comparison of the advantages and disadvantages of two ignition methods for cutting guns:

method	advantage	disadvantage
First open the acetylene valve, then ignite, and finally open the oxygen valve	It can release acetylene/air mixture to avoid detonation during ignition, and it is easy to detect whether the cutting gun is blocked or leaking. The flame changes from weak to strong, and the combustion is relatively stable.	Black smoke will be emitted when the ignition is first started
First open the oxygen valve, then open the acetylene valve, and then ignite	Can eliminate black smoke during ignition	There is a popping sound when igniting, and if the cutting gun is blocked and the switch is not tight, oxygen may enter the acetylene system, creating a backfire explosion condition.

From the above comparison, we know that for inexperienced individuals, for safety reasons, it is recommended to use the first method; For those with certain experience, or when multiple cutting guns are working simultaneously in a narrow workspace with poor ventilation, to improve environmental hygiene conditions, the second method can be used to open the valve and ignite. When using both methods of operation, the preheating oxygen valve should be rotated slowly. If it is too fast, the suction force inside the cutting gun will suddenly increase, causing the acetylene supply to fall behind and resulting in tempering. When extinguishing the flame at the end of work, the cutting gun should first turn off the oxygen source, then turn off acetylene and preheat oxygen in sequence.