What should be paid attention to when welding galvanized steel pipe

The welding of galvanized steel pipe should pay attention to:
1. Galvanized steel pipes with a pipe diameter greater than 100mm should be connected by flanges or ferrule-type special pipe fittings.
2. For the weld between galvanized steel pipe and flange, to ensure the welding quality, the weld joint should be galvanized, and the galvanized layer should be cleaned by hand grinding wheel or sandpaper, or the galvanized layer should be removed by gas welding flame.
3. The weld between the galvanized steel pipe and the flange should be galvanized twice.

Measures to ensure welding quality include:
1. The human factor is the key point of control in the welding of gas-fired galvanized steel pipes. Due to the lack of necessary post-welding control means, it is easy to cut corners and materials, which affects the quality; at the same time, the special welding of galvanized steel pipes makes it difficult to guarantee the welding quality. Therefore, before the start of the project, welders who are skilled in technology and hold corresponding boiler and pressure vessel certificates or equivalent welder certificates should be selected for necessary technical training and disclosure. Permission to enter the site for welding. It is not allowed to be replaced at will to ensure that the welders who weld the pipeline are relatively stable.
2. Control of welding consumables: ensure that the purchased welding consumables are from regular channels, have quality assurance certificates, certificates of conformity, and meet the process requirements; the procedures for acceptance of welding consumables, delivery of materials must be formal and complete, and the recycling of welding rod heads should be strictly controlled to ensure the flow direction, Dosage; Welding consumables should be baked strictly according to the process, and no more than half a day's dosage should be distributed at a time.
3. Welding machine; Welding machine is a welding tool, which must ensure reliable performance and meet the process requirements; the welding machine must have a current and voltmeter that has passed the verification to ensure the correct implementation of the welding process. The welding cable should not be too long, and the welding parameters should be adjusted if it is longer.
4. Welding process method: ensure the strict implementation of special operation methods for galvanized steel pipes, check the groove before welding according to the welding process, control welding process parameters and operating methods, check the appearance quality after welding, and add non-destructive testing after welding if necessary. Control the welding level and the number of welding consumables for each pass.
5. Welding environment control: ensure that the temperature, humidity, and wind speed during welding meet the process requirements. Welding is not allowed under unconditional conditions.