English
For thin-walled tube tungsten electrode TIG welding is concerned, arcing is very important, because in the arc process, the base material due to contact with the tungsten electrode may lead to contamination of the base material. Action should be heated tungsten electrode base material and should not be consumed in the welding process. Similarly, the contact base material can contaminate the tungsten electrode.
For less demanding general welding work, there are still scratching the use of tungsten electrode base material to arcing, and then leave the metal surface welding. Those high quality requirements of welded joints, especially the requirement to use X-ray nondestructive testing for detecting the welded joints, this method since the tungsten scratch the surface of the base material may lead to joint discontinuities or defects, and therefore not be used.
Therefore, the thin-walled tube tungsten electrode welding often use something called "high-frequency" approach arc, can take advantage of the power contained within the device can also be used in the operation of external accessories. This high frequency arc starting method can provide an electronic channel to the Arc field, so you can skip the current arc between the tungsten electrode and the base material. This provides a way for the non-contact arcing method. There are a cross between a high-frequency and intermediate scratch arcing method, which gently tungsten electrode contacting the base material to produce a small voltage when the arc is ignited, light lift the torch. This method avoids the chance to scratch along the base material of the tungsten electrode, reducing pollution. However, this method still can not achieve the kind of clean, high frequency arc starting method in some high demand still does not allow the use of welds.
