The operation of cutting guns requires safety as the first prerequisite, and its core procedures revolve around three major links: "pre inspection, standardized operation, and emergency response". Any negligence in any link may cause fire, explosion, or personal injury.
1、 Before operation: Anran inspection and preparation
Check the integrity of the equipment, confirm that there are no cracks or leaks in the cutting gun body and hose, that the cutting nozzle is not blocked or damaged, and that all connections (such as oxygen and acetylene valves) are well sealed.
Verify the gas type and pressure. Oxygen and acetylene meters must be within the effective calibration period. Acetylene cylinders must be equipped with flashback arresters, and the distance between the two cylinders should not be less than 5 meters, and the distance from the open flame should not be less than 10 meters.
Clean up the work site, remove flammable and explosive materials (such as oilcloth and paint buckets) around, equip sufficient fire extinguishers (dry powder or carbon dioxide type), and lay fireproof blankets (based on actual reports) when necessary.
Wear protective equipment, including impact goggles, flame-retardant work clothes, and safety shoes. Wear heat-resistant gloves during operation, and tuck long hair into a work cap.
2、 In operation: Standardized processes and taboos
When opening the gas cylinder, follow the sequence of "opening acetylene first, then opening oxygen", and open the valve slowly to avoid sudden pressure rise and damage to the instrument; When adjusting the flame, first ignite acetylene and adjust it to no black smoke, then gradually turn on oxygen until a clear "neutral flame" is formed (with distinct flame core, inner flame, and outer flame).
During the cutting process, keep the cutting nozzle perpendicular to the workpiece or maintain a fixed inclination angle (usually 30 ° -45 °) as required. The height of the cutting nozzle should be controlled at 3-5mm to avoid flame dispersion caused by being too high and burning the cutting nozzle due to being too low.
It is prohibited to cut in pressurized containers or enclosed spaces. If it is necessary to work in a confined space, ventilation and air exchange should be carried out first, oxygen content (19.5% -23.5%) should be detected, and a dedicated person should be arranged for supervision.
Do not touch the nozzle of the cutting gun or the workpiece that has just been cut with your hands during operation to prevent high temperature sickness; It is strictly prohibited to use a cutting gun as a "tool" to strike or pry objects, in order to avoid deformation and air leakage of the gun body.
3、 After operation: Closing and emergency handling
When turning off the equipment, follow the order of "turn off oxygen first, then turn off acetylene". Close the oxygen valve on the cutting gun first, then the acetylene valve, and finally close the main valve of the gas cylinder. Release the residual gas in the hose and remove the instrument.
Clean up the work site, extinguish all open flames, check for any remaining sparks (such as debris ignited by sparks), confirm that there are no safety hazards, neatly store the cutting gun and hose, return the gas cylinder to its original position and secure it.
If there is a backfire (flame backflow into the gun body accompanied by a "sizzling" sound), the acetylene valve of the cutting gun should be immediately closed, followed by the oxygen valve. After the gun body cools down, check the backfire preventer and confirm that there are no faults before reusing it.
If there is a gas leak, immediately close the main valve of the gas cylinder, open the ventilation on site, and do not turn on or off any electrical appliances or generate sparks. After the leak stops and the gas spreads, investigate the leak point and repair it.
4、 Additional requirements for special scenarios
When cutting underwater, it is necessary to use a one-on-one underwater cutting gun. Before the operation, check the waterproof (based on actual reports) seal, confirm that there is no interference between the diving equipment and the cutting gun system, and equip emergency rescue personnel on the water surface.
When cutting non-ferrous metals (such as aluminum and copper), it is necessary to strengthen ventilation, wear dust masks, and avoid inhaling metal smoke and dust; When cutting thick plates, it is necessary to preheat the edge of the workpiece to a red hot state before turning on the cutting oxygen.