1. Construction Preparation: Familiarize yourself with the drawings → Conduct a site survey → Determine the cutting dimensions based on the actual site dimensions.
2. Cutting Pipe Sections: Transport the pipe sections to be cut to the installation location and cut them on the ground to the required length. Elbow punching is performed using an oxygen-free acetylene flame. After cutting, polish the inside and outside of the bevel to remove burrs and sharp edges, preventing stress concentration in the cutting area, which could lead to welding deformation or stress cracking.
3. Pairing and Installation: Pair the two pipe sections together, adjusting the bevel gap to ensure assembly quality. Welding deformation is considered during assembly, and anti-deformation methods are generally used for pretreatment. During assembly, consider ease of operation and safety; avoid forcefully striking the pipe sections to prevent damage to the stainless steel pipe wall.
4. Weld Repair: If the pipeline is found to be unqualified after non-destructive testing, it must be repaired by welding. A repair plan should be developed and approved by superiors. The grade of weld repair should not be lower than the minimum requirements specified in the qualification standards. Welds that are generally not allowed to be reworked have defects such as porosity, slag inclusions, lack of fusion, and cracks.
