Welding of general order: Preheat rust before welding inspection → → assembly and welding pad and arc board → welding → test
5.3.1 groove angle before welding inspection, blunt edge, gap, and the amount of the wrong mouth, groove and on both sides of the rust, oil, iron skin, etc. should be cleaned.
5.3.2 preheating. Before welding gas welding or specially roasted gun uniform heating of the groove and the base metal on both sides of each of the 100mm range and surface temperature measurement temperature, to prevent the temperature does not meet the requirements or the surface of the partial oxidation, preheat temperature.
5.3.3 Recheck the preheat temperature, if the temperature is not enough should be re-heated to make it meet the requirements.
5.3.4 assembly and welding pad and arc plate, surface cleanliness requirements the same as the surface of the groove, pad and base metal snapping, should be solid arc plate and base metal welding.
5.3.5 Welding Wire China: the first layer of weld bead should seal the junction of the the groove base metal pad, then by trace layer tired solder to fill the groove, After every weld must be removed before welding slag and spatter, weld defects should be promptly rubbed off and repair.
5.3.6 an interface must be continuous welding finished, as a last resort midway stop welding, insulation slow cooling process, the regulations should be re-heated again before Welding Rod

5.3.7 in case of rain, the snow should stop welding, the component weld around and above should have windshield, canopy, wind speed greater than 5m / s should stop welding. Ambient temperature is below zero, should be required to take the measures of preheat and post-heat construction.
5.3.8 carbon structural steel should be cooled to ambient temperature, low-alloy structural weld