The welding of steel pipes

The welding of steel pipes can be seen in all kinds of large-scale projects. The galvanized steel pipes are also widely used at present. There are many welding methods for galvanized steel. Generally, gas welding, manual arc welding, 2×2 square tubing, CO2 gas shielded welding and burying are commonly used in galvanized steel structures. Arc automatic welding, tungsten argon arc welding and other methods.

Gas welding, which used to be used for the welding of galvanized pipes, is currently eliminated in the installation industry due to the inconvenience of gas welding heat input, easy to produce defects, and poor mechanical properties of welds. Gas welding damages the galvanized layer.

CO2 gas shielded welding has good welding performance for galvanized steel. When using suitable welding specifications and matching shielding gas and welding materials, high quality welded joints can be obtained. This method is rarely used in engineering practice.

Tungsten argon arc welding, arc energy concentration, less damage to the galvanized layer, and easy to form a good single-sided welded double-sided forming joint, is a welding method worthy of use, but the welding speed, slower, cost More expensive.
How to control the welding quality of galvanized steel pipe?

Control from five aspects: people, materials, machinery, law, and ring.

The one-person factor is the focus of the welding control. Therefore, before the welding, the skilled welder who holds the welder’s certificate should be selected to carry out the necessary technical training and delivery. It is not allowed to be replaced at will, to ensure that the pipe welder is relatively stable.

2 Control of welding consumables: Ensure that the procurement materials are regular channels of welding consumables, have quality assurance books, certificates, and meet the process requirements; the welding heads are strictly controlled to ensure the flow direction and dosage; the welding consumables must be baked strictly according to the process, and once Disbursement for no more than half a day.

3 Welder: The welder must ensure reliable performance and meet the needs of the process; the welder 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 long.

4 Welding process: Ensure the strict implementation of the special operation method of galvanized pipe, weld process pre-weld groove inspection, welding process parameters, operation method control, post-weld appearance quality inspection, and increase non-destructive testing after welding if necessary. Control the welding level and the amount of welding consumables per pass.

5 Welding environment control: Ensure that the temperature, humidity and wind speed during welding are in accordance with the process requirements.

Galvanized welded pipes, also known as galvanized steel pipes, are divided into hot-dip galvanizing and electro-galvanizing. The hot-dip galvanizing galvanized layer is thick, with uniform plating, strong adhesion and long service life. As the name suggests, the welded pipe is a weldable steel pipe. The above content is expected to help everyone.