Principle of automatic butt welding machine for steel pipe

The preheating flash welding process: before the continuous flash welding is stopped, the welding machine is preheated to the reinforcing steel. Clamp the steel bar on the jaw of the butt welder. After the power is turned on, the open end is used to make the end face of the steel bar smash with less pressure, and then separate, so that it is always separated and snoring, every time it is smashed, because of the resistance of the smashing resistor and the external resistance of the steel bar. The welding zone is heated, and when it is opened, a flash of time is generated. Repeatedly repeated above, the temperature is gradually reduced, and the warm-up process is realized. After preheating, the flash and upset are stopped, and the two processes are the same as continuous flash welding. When adopting the un2-150 type or un17-150-1 type butt welder to stop the welding of large-diameter steel bars, it is advisable to adopt the sawing or gas cutting method to stop the flat end treatment of the steel bar end face; then adopt the preheating flash welding process, the hydraulic flash pair The welder shall comply with the following requirements: the flashing process shall be intense and stable; the upset forgings shall be raised; the precision adjustment shall be made and the starting point and the stopping point of each process shall be strictly controlled.

The use of butt welder should: (1) The butt welder should be placed indoors or in a rainproof work shed, and should have a solid ground or zero. When multiple butt welders are arranged side by side, the distance between them should not be less than 3m, and should be separated from the grid with different phase, and the circuit breaker should be separated. (2) Before welding, it should be reviewed and confirmed: the pressure mechanism of the welder should be dexterous, the clamp should be stable, and the air pressure and hydraulic system must not leak. (3) Before welding, the secondary voltage shall be adjusted according to the section of the welded steel bar, and the steel bar beyond the diameter of the butt welder shall not be welded. (4) The snoring point and electrode of the circuit breaker shall be honed on time, and the secondary circuit connection bolt shall be tightened as scheduled. The temperature of the cooling water must not exceed 40°, and the displacement should be adjusted according to the temperature. (5) When welding long steel bars, brackets should be provided. (6) The flashing area shall be provided with a baffle, and the staff related to welding shall not enter. (7) When welding in winter, the temperature should not be lower than 8°. After the homework, the cooling water in the machine should be exhausted.