①Clean the soil and debris at the end of the pile before connecting the pile, and you can choose to use a wire brush to clean it.
②The upper and lower piles are aligned, the deviation of the upper and lower piles should be less than 2mm, and the straightness of the upper pile should be ensured. 
③When welding, two people should weld symmetrically together, and the welds should be continuous and full, and there should be no shortcomings in pipe pile construction, such as undercut, slag inclusion, weld bead, etc. There should be at least two or more layers of welding, and the welding slag should be knocked off with a small hammer. The carbon dioxide welding method is used for welding, and the pressure can be continuously applied without cooling and welding.

The welding process is as follows:

①Check whether the connection between the workpiece and the ground wire, welding torch, wire feeder, gas cylinder, barometer, air pipe, etc. is accurate and reliable. If there is a large (small) current file on the panel, use a small current file for voltages below 5 files.

②Install the wire reel with the welding wire on the wire feed reel shaft, adjust the wire feed wheel and contact tip according to the wire diameter, and manually feed the welding wire into the wire feed hose, and press the wire feed wheel.

③Turn on the power supply of the welding machine and turn on the "voltage adjustment" switch to the required position. The current adjustment is probably in the right position (the exact position should be adjusted during welding); for 0.8~1.0mm welding wire, the wire feeding speed is roughly 3~18 M/min.

④Select the welding method according to actual needs: when welding the continuous long seams, turn the two knobs of "spot welding" and "intermittent welding" counterclockwise to the bottom; active short welds (automatically stop after welding for a period of time), change " Turn on the "Intermittent Welding" knob, and adjust the welding time as required; for active intermittent welding, turn on the "Spot Welding" and "Intermittent Welding" knobs to match and adjust the corresponding welding cycle time and welding time.

⑤Open the gas cylinder valve and adjust the gas flow. Generally, choose a scale of 3-15 liters/minute to check whether the gas path is leaking; press the gun switch to observe whether the wire feeding and air feeding are normal.  

⑥Hold the welding gun so that the nozzle is 8-12mm higher than the workpiece, about 10-20 degrees from the straight direction of the welding seam, and the welding seam can be aligned with the welding wire first.

⑦Press the gun switch, after the arc is ignited, move the welding torch evenly along the welding seam (try to keep the length of the welding wire unchanged), and adjust the welding standard matching according to the actual situation to obtain a delicate welding seam. Release the gun switch to complete a welding cycle.

⑧After the welding operation is completed, close the gas cylinder valve, loosen the wire pressing handle of the wire feeder, press the gun switch to release the remaining gas in the barometer, and finally turn off the power supply of the welding machine and the main power supply.