The difference between AC argon arc welding machine and DC welder
Compared with AC power supply, the DC power supply can provide stable arc and stable droplet transfer. Once the arc is ignited, DC arc can maintain continuous combustion; AC welding power source, the voltage and current change of direction, and every second to extinguish the arc and re ignited 120 times, arc can not be continuous and stable combustion. In the case of low welding current, the DC arc has a very good wetting effect on the melted weld metal, and can regulate the weld size, so it is very suitable for welding thin parts. DC power supply is more suitable for overhead welding and vertical welding than AC power supply, because DC arc is relatively short. But sometimes the arc of DC power supply is a prominent problem, and the solution is to change to AC power supply. For the AC or DC power supply welding and design of AC and DC dual electrode, the vast majority of DC power supply conditions in the welding applications better. In manual arc welding, the AC welder and some additional devices are cheap and can avoid the harmful effects of arc blowing force as much as possible. But in addition to lower equipment costs, the use of AC power supply welding effect is better than the DC power supply. The arc welding power source (CC) with steep drop characteristics is most suitable for manual arc welding. The voltage change corresponding to the current change shows that the current decreases with the increase of arc length. This characteristic limits the arc current even if the welder controls the size of the bath. When the welder moves the electrode along the weldment, it is inevitable that the length of the arc changes constantly, while the steep down arc welding power supply ensures the stability of the arc during these changes.
The difference lies in the use of different welding and argon arc welding machine with gas tank, and DC welder need only electrical and conventional electrodes. Argon arc welding of metal material processing is very thin, and DC welding processing thickness less than 3MM material processing inconvenience. TIG welding wire electrode is disc type electrode. The different DC welder.
The difference between AC argon arc welding machine and DC welder:1, DC TIG welding, the DC positive connection with argon gas protection, with between the electrode and the welding arc in certain requirements (welding current), heating and melting of the parent material, adding wire wire to melt into the molten pool, the formation of weld cooling.In addition, 2 pulse argon arc welding, DC TIG welding specification, can independently adjust the peak current, base current, pulse width, pulse period or frequency parameters, compared with DC argon arc welding has the following advantages:(1) increasing the depth to width ratio of the weld, the width of the weld can be increased to 2:1 when the stainless steel is welded(2) to prevent burning, in the thin plate welding or thick plate backing welding, with the peak current through the time, the weldment is welded through, before the pool obvious subsidence, go to the base value current, make the metal solidification. Also, there is a small current to maintain the arc until the next peak current is circulating.(3) reducing the heat affected zone and welding the heat sensitive material, reducing the pulse current through the time and the base current value can reduce the range of the heat affected zone to the minimum, so that the welding deformation is small.(4) increase the stirring of the molten pool, at the same average current value, current value than a constant current high current pulse peak, so the arc force, strong mixing effect, which helps to reduce joint at the bottom of the hole and may not fusion phenomenon. In small current welding, the higher pulse current peak current enhances the arc stiffness and eliminates the arc drift phenomenon.
