The general order of welding: pre-welding inspection → preheating rust → installed welding plate and arc plate → welding → inspection
1. Before welding, check the groove angle, blunt edge, gap and wrong volume, groove and inside the rust spots, oil, iron oxide skin should be cleaned.
2. Preheating. Welding with gas welding or special roasted gun on both sides of the 100mm and the base of the base material within the uniform heating, and use a surface thermometer to measure the temperature, to prevent the temperature does not meet the requirements or surface local oxidation, preheating temperature.
3. Re-check the preheating temperature, such as the temperature should be re-heated to meet the requirements.
4. Install the welding plate and arc plate, the surface cleanliness requirements and the same groove surface, pad and base metal should be tight, arc plate and base metal welding should be solid.
5. Welding: the first layer of the bead should be sealed in the groove between the base metal and the connection of the pad, and then by-line layer by layer welding to fill the groove, each weld after welding, must remove the slag and splash Material, the emergence of welding defects should be timely grinding and repair.
6. An interface must be continuous welding, such as last resort and stop welding, should be carried out by slow cooling treatment, and then welding, should be re-installed according to the provisions.
7. In case of rain, snow should be stopped when the weld around the component and should be above the wind, canopy, wind speed greater than 5m / s should be stopped welding. Ambient temperature below zero, should be required to take preheat and after the thermal measures construction.
8. Carbon structural steel should be cooled in the weld to the ambient temperature, low-alloy structural steel should be completed after 24 hours, the weld inspection.
9. The welder and the inspector should fill in the job record form carefully.