First, during the material preparation phase, pipe cutting should be performed using a dedicated electric pipe cutter according to the design dimensions. The cut must be vertical, and pipes thicker than 3mm should be beveled at a 60-80 degree angle to ensure mechanical strength. After cutting, the pipe ends must be thoroughly deburred and the interior cleaned to prevent residue from damaging the passivation film and causing corrosion. For pipe sections requiring welding, the welded areas should be cleaned of grease and debris, and then symmetrically spot welded at 6-8 locations to ensure no misalignment of the pipe axis and that the butt joint gap is no greater than 2mm.

Welding is a critical step in ensuring installation quality. TIG welding should be used with high-grade welding wire. During welding, the inner wall of the pipe should be protected with argon gas to prevent oxidation. After welding, the weld seam should be mechanically polished or pickled for passivation to restore corrosion resistance. It is particularly important to note that stainless steel pipes must not come into direct contact with carbon steel supports. Chloride-free insulating gaskets must be used to isolate them. Wall penetrations should be covered with steel casing and filled with insulating material. When connecting flanges, strictly control the levelness deviation to no more than 1mm/m. Use segmented, symmetrical jump welding to prevent deformation, and keep each weld length between 100-200mm.

Allow for thermal expansion during installation. The ends of the U-shaped pipe should not be completely fixed. It is recommended to use spring brackets or allow for expansion to accommodate temperature fluctuations. Corrosion-resistant gaskets should be used as sealing materials; ordinary rubber gaskets may corrode and leak due to the media. For specialized applications, such as the pharmaceutical or food industries, the pipe interior should be electrochemically polished to ensure a surface roughness Ra ≤ 0.8μm to meet hygiene requirements.

After installation, a system acceptance test is required, including a water pressure test at 1.5 times the working pressure, with no leakage observed for 30 minutes. Ultrasonic testing is used to inspect weld quality and eliminate defects such as cracks or pores. The elevation deviation of the horizontal section should be controlled within ±10mm, and the flange surface levelness should be re-measured and confirmed. During long-term use, it is recommended to clean the pipe interior every six months to remove microbial film and impurities to maintain system cleanliness. Through the above full process control, the installation quality and service life of the stainless steel U-shaped pipe can be ensured.