Special features of welding and brazing using electric gas generators of hydrogen-oxygen mixtures

摘要

Gas welding and brazing is used widely in many branches of industry. Of the fuel gases used, the best characteristics are formed by acetylene and propane, operating in a mixture with oxygen. However, the service expenditure (the price of the generator of acetylene, calcium carbide oxygen, reducing valves, cylinders) increases the production costs. Equipment is cumbersome and difficult to operate in transport from operation areas. At present, various water electrolysers are available for producing oxygen-hydrogen mixtures, and also for separate production of hydrogen and oxygen for welding, brazing, heat treatment and special operations. The application of the resultant gases of welding, brazing and cutting of metals is extremely attractive. Water is a cheap, available and safe energy carrier. In combustion of hydrogen with oxygen the amount of harmful substances formed is considerably more and water forms again. In electrolysis of 1 cm~3 of water approximately 800 cm~3 of gas is produced. There are standard industrial systems and small electric gas generators which can be used efficiently for different operations. The expenditure and production costs are considerably lower with the quality of brazed joints very high. The expenditure consists mainly of the cost of the brazing alloy, the flux, electric energy and distilled water.