What should we pay attention to when welding galvanized steel pipe

The welding of galvanized steel pipe should pay attention to:

1. Galvanized steel pipes with a steel pipe diameter greater than 100mm should be connected by a flange or ferrule-type special pipe fittings.

2. To ensure the welding quality of the welding part of the galvanized steel pipe and the flange, the galvanizing of the welding joint should be treated, and the galvanized layer should be cleaned with a hand grinding wheel or sandpaper, or the galvanized layer should be removed with a 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 galvanized pipes. Due to the lack of necessary post-weld control methods, it is easy to cut corners and affect the quality; at the same time, the special welding of galvanized pipes makes it difficult to ensure the welding quality. Therefore, before the start of the project, a welder who is skilled in technology and holds the corresponding boiler and pressure vessel or equivalent welder certificate should be selected, and the necessary technical training and disclosure should be carried out. Permission to enter the site for welding. It should not be replaced at will, to ensure that the welding personnel of the pipeline are relatively stable.

2. Control of welding consumables: ensure that the purchased welding consumables are from regular channels, with quality assurance certificates and qualification certificates, and meet the process requirements; the acceptance of welding consumables and the procedures for receiving and issuing materials must be formal and complete, and the recycling of electrode heads is strictly controlled to ensure the flow direction. , dosage; welding materials should be baked strictly according to the process, and the dosage should not exceed half a day at a time.

3. Welding machine: The welding machine is a welding machine and must ensure reliable performance and meet the needs of the process; the welding machine must have a qualified current and voltmeter to ensure the correct implementation of the welding process. The welding cable should not be too long, and the welding parameters should be adjusted when it is longer.

4. Welding process method: ensure the strict implementation of the special operation method of the galvanized pipe, carry out the pre-welding groove inspection according to the welding process, control the welding process parameters and operation methods, inspect the appearance quality after welding, and increase the post-weld non-destructive inspection if necessary. Control the welding level and the number of welding consumables per pass.

5. Welding environment control: ensure that the temperature, humidity, and wind speed during welding meet the process requirements. Welding is not allowed when unconditional.