Welding method and basic operation of oxygen welding

【Summary Description】 Oxygen welding method and basic operation: 1. Inspection before operation: the fasteners of 1.1 acetylene generator (acetylene bottle), oxygen bottle, hose connector and valve shall be fastened firmly without looseness, damage and air leakage. Do not stick oil to oxygen accessories, hoses and tools. 1.2 oxygen cylinders and acetylene pipes shall not be used due to leakage, aging, cracking and other reasons. Pipes shall be kept clean and free of debris. 2. Operation steps: 2.1 acetylene cylinder gas welding (cutting) Operation steps: 2.1.1 Reliably connect acetylene pressure reducer with acetylene cylinder valve, oxygen pressure reducer with oxygen cylinder valve, oxygen hose with oxygen pressure reducer, acetylene hose with acetylene pressure reducer, oxygen and acetylene hose with welding (cutting) torch. 2.1.2 Open the acetylene cylinder valve and the oxygen cylinder valve respectively. 2.1.3 Butt welding (cutting) torch can only work after ignition. 2.1.4 After the work is completed, first close the welding (cutting) acetylene valve and oxygen valve in turn, then close the acetylene cylinder valve and oxygen cylinder valve, then remove the oxygen and acetylene hoses, check and clean the site, and extinguish the fire before leaving. 2.2 Gas welding (cutting) operation steps of medium pressure acetylene generator: 2.2.1 reliably connect and weld (cut) the oxygen pressure reducer and oxygen cylinder valve, oxygen hose and oxygen pressure reducer, acetylene generator, oxygen and acetylene hose. 2.2.2 Rinse the acetylene generator with clean water to remove mortar and residue. 2.2.3 Put the calcium carbide of suitable size into the calcium carbide basket, and the amount of calcium carbide added at one time should not be too much. 2.2.4 Put the calcium carbide basket into the acetylene generator, add an appropriate amount of water, and tighten the upper cover. 2.2.5 Open the oxygen cylinder valve. 2.2.6 Ignite the butt welding (cutting) torch to start work. 2.2.7 After the work is finished, close the acetylene valve and oxygen valve of the welding (cutting) torch in turn, then close the oxygen cylinder, open the drain valve of the acetylene generator, then open the cover, rinse it, check the site and leave after eliminating the kindling. 3. Operation precautions: It is forbidden to store inflammable and explosive materials at the 3.1 welding site, and it is equipped with fire fighting equipment, sufficient lighting and good ventilation. 3.2 acetylene generator (acetylene cylinder) and oxygen cylinder within 10m, no fireworks. The distance between the acetylene generator and the oxygen cylinder shall not be less than 7m. The protective overalls used by 3.3 welders shall not be tucked into the trousers, the trouser legs shall not be rolled, and the shoe mouth shall not be tied outside the trouser legs. 3.4 Each acetylene hose must have tempering facilities, and the use of floating barrel acetylene generators is prohibited. 3.5 check equipment, accessories and piping for leaks and test with soapy water. Open fire or smoking is not allowed around. Copper shall not be used for 3.6 acetylene generator parts and random tools to prevent explosion caused by copper acetylene contact with acetylene. Copper alloys with a copper content of less than 70% may be used. 3.7 calcium carbide shall have suitable lumpiness. The amount of calcium carbide added at one time should not be too much. Do not focus on the use of small pieces of calcium carbide, do not use the last fragrance, in order to prevent acetylene generator pressure rise caused by violent reaction and explosion. 3.8 When medium pressure acetylene generator is used (when the working pressure reaches 1.5Mpa, pressure gauge and safety valve shall be installed in addition to anti-backfire device), the pressure shall be kept at the rated value, the safety valve shall operate reliably, the water shall be kept clean frequently, and the mortar decomposed by calcium carbide shall be removed in time. The air chamber, air pressure extrusion chamber and flashback preventer of 3.9 stamping acetylene generator shall be installed with pressure relief film of corresponding area, and the flashback preventer shall be equipped with one-way valve device. 3.10 when oxygen is used indoors or outdoors, it must be properly placed to prevent dumping. When there is outdoor operation, the oxygen cylinder should be installed in the pergola to avoid strong sunlight. 3.11 oxygen cylinders should generally be placed upright. Individual cases need to lie down, the bottle strength is slightly higher. 3.12 oxygen cylinder and acetylene cylinder are prohibited from being stained with grease. Do not use greased gloves to handle oxygen and acetylene cylinders. The cap of the 3.13 oxygen cylinder must be unscrewed by hand or with a wrench. 3.14 loosen the oxygen bottle and acetylene bottle valve not too fast, in order to prevent pressure flow surge, resulting in the valve out of the accident. The nozzle of the 3.15 oxygen cylinder shall not be contaminated with grease. In winter, if the bottle mouth freezes, it is not allowed to bake with fire, and can only be heated with hot water or steam. 3.16 do not use up the oxygen in the oxygen cylinder, and finally leave at least 0.05Mpa of oxygen. 3.17 acetylene bottle can not be subjected to severe vibration and impact, so as to avoid the bottle of porous filling sink to form a cavity, affecting the storage of acetylene. 3.18 acetylene bottles should be placed upright when working to prevent copper from flowing out with acetylene to avoid danger. The surface temperature of 3.19 acetylene cylinder shall not exceed 30-400 ° C. Too high temperature will reduce the solubility of copper propylene to acetylene, resulting in a sharp rise in acetylene pressure in the bottle. The connection between the 3.20 pressure reducer and the bottle valve must be reliable. No air leakage is allowed to avoid explosion accident. It is 3.21 not to use up all the acetylene in the acetylene bottle. Finally, leave 0.1Mpa acetylene gas and close the cylinder valve. When opening the oxygen or acetylene valve 3.22, it is strictly forbidden to hit to prevent sparks. After the 3.23 work is completed, the oxygen valve and acetylene valve should be closed in time, and the welding torch is not allowed to be placed in the container or under the workbench. When the 3.24 acetylene pipeline is blocked, it is strictly prohibited to use oxygen compressed air to blow it off. When the 3.25 is tempered, close the oxygen valve first, and then close the acetylene valve; when the acetylene pipeline is on fire, the method of bending the pipeline can be used to extinguish the fire. 3.26 For pressure vessels, airtight containers, various oil drums, pipelines, and workpieces containing flammable liquids, toxic, harmful, flammable and explosive substances, they must be removed in advance to release the pressure of the container and pipeline, and eliminate the airtight state of the container (Open the opening and unscrew the lid) before it can work. When 3.27 welding and cutting closed hollow, there must be an air outlet. Welding in the container must be supervised outside and ventilation measures must be taken. Welding in painted or sprayed plastic containers is prohibited. When 3.28 high-altitude welding, in addition to complying with the relevant provisions of the "high-altitude operation operating procedures", safety measures should also be taken. There are people on the ground watching. Put down the flammable and explosive materials must be moved 10 meters away. After the 3.29 work is completed, the acetylene generator should be cleaned, and the work site should be checked and cleaned, and the fire can be extinguished before leaving.

Previous Page

Why has the soldering process endured and will continue in the future?

Next Page

Explain the secret of the hard welding process in detail.