1) The characteristic of this Butt Welding Technology of program-controlled reduced voltage flash butt welding is that a higher secondary no-load voltage is used at the beginning of the flash to facilitate the stimulation of the flash. When the end face temperature rises, a low voltage flash is used and the maintained flash speed remains unchanged to improve thermal efficiency.
When approaching upsetting, the secondary voltage is increased to make the flash stronger to increase the self-protection effect.
Compared with preheated flash butt welding machine, program-controlled reduced voltage flash butt welding has the advantages of short welding time, low power requirement, and uniform heating.
2) The characteristic of pulse flash butt welding is that during the feeding stroke of the movable clamp, a reciprocating vibration stroke is superimposed through the hydraulic vibration device, with an amplitude of 0.25-1.2mm and a frequency of 3-35Hz. tune.
Due to vibration, the end faces of the weldment are alternately short-circuited and pulled apart, resulting in a pulse flash.
Compared with ordinary flash butt welding technology, pulse flash butt welding technology has no spontaneous explosion of the lintel, the spattered particles are small, and the fire mouth is shallow, so the thermal efficiency can be more than doubled, and the upsetting amount can be reduced to 2/3-1/ 2.
The above two Butt Welding Technology are mainly to meet the needs of flash butt welding of large-section workpieces.
3) Rectangular wave flash butt welding technology. Compared with power frequency AC sine wave flash butt welding, this welding method can significantly improve the stability of the flash.
Because the sine wave power supply will cause the flash to be interrupted momentarily when the voltage is close to zero, while the rectangular wave can generate flash evenly throughout the entire cycle. Independent of voltage phase.
The number of flashes per unit time of the rectangular wave power supply is 30% higher than that of power frequency AC. The metal particles sprayed are fine, the burner is shallow, and the thermal efficiency is high.
The rectangular wave frequency can be adjusted within the range of 30-180Hz. This method is mostly used for continuous flash butt welding of thin plates and aluminum alloy wheels.
