Full TIG welding backing makes no difference in the process, the whole arc for thin-walled small diameter pipes (DN50 general and below, the wall thickness of 4 mm) or less, the purpose of guarantee good weld root quality appearance imaging. When a large diameter, thick wall thickness should be used for welding backing manual welding to cover up, cover the surface with manual welding is the the Dayong diameter manual welding can ensure the quality of the appearance and ergonomics than TIG cost lower than the TIG.
Full TIG diameter of less than 4 inches (DN100) pipeline general requirements for welding backing surface covered arc, thus ensuring that the inner layer of the weld quality improved production efficiency, weld molding is relatively good. Large diameter pipes commonly used argon ITU welding, welding backing first, then other parts of the welding welding. The smaller pipe TIG welding can be used.
The welding backing benefits for the pipe wall molding, for example, considering the pipeline after a few years of running pig by pigging, so you can avoid the sinker accident. Generally argon primer, the welding filler cap surface and then there are generally thin-walled small-diameter pipe directly welding, to the above-said DN50. Welding backing is the underlying pipe welding TIG playing again at the end, and then welding package; TIG the entire welding using welding process. A first low-speed fast construction costs, but not to the high requirements of the pipeline.
Generally high quality requirements for welding, unable to make do the back gouging the weld need to do welding backing, SMAW cover up to. Such as pipe welding, often used in welding backing, then SMAW cover up. TIG-ray energy, forming a good weld appearance, but the relatively high cost. Welding backing process, you can get the quality of welded joints. Welding backing welding process, the excellent quality of the joint welding of boiler water wall, superheater, economizer ray detection, weld levels in II above.
Post time: Oct-11-2019