Non-standard flanges are components used for connecting pipes and valves to each other. They feature holes and bolts for a tight connection between two flanges. Known for their excellent performance, non-standard flanges are widely used in many industries and are one of the mechanical components commonly used in industrial equipment and production. They also serve as one of the connection points, primarily located between the ends of pipes or at equipment inlets. Below are the precautions to consider when using non-standard flanges.

To prevent intergranular corrosion caused by the法兰盖 overheating, the welding current should not be too high, about 20% less than that of carbon steel welding rods. The arc should not be too long, the cooling rate between layers should be fast, and the weld should be smaller. The narrower, the better.

2. The electrode should be kept dry during use. Perovskite-type electrodes should be dried for one hour at 150°C, while low-hydrogen electrodes should be dried for one hour at 200-250°C (avoid repeated drying as it may cause the coating to crack). Prevent the welding rod coating from adhering to oil or other contaminants to avoid increasing the carbon content in the weld, which could affect weld quality.

When welding non-standard flanged pipe fittings, repeated heating can lead to the precipitation of carbides, thereby reducing corrosion resistance and mechanical properties.

4. After welding non-standard flanged pipe fittings, there are large quenched flanges that are prone to breakage. If welding with the same type of chromium stainless steel welding rod, the parts must be preheated to above 300℃ and then cooled slowly around 700℃. If the welded parts cannot undergo post-weld heat treatment, then non-standard flanged pipe electrodes should be used.

5. To enhance corrosion and weldability, non-standard flanges should be appropriately added with stabilizing elements such as Ti, Nb, Mo, etc., which offer superior weldability compared to chrome non-standard flanges. When using the same type of chrome non-standard flange welding rods, the flange should be preheated to above 200℃ and then tempered to around 800℃. If the welded parts cannot undergo heat treatment, non-standard flange tube welding rods should be used.

6. Non-standard flange pipe fittings exhibit excellent corrosion and oxidation resistance during welding, and are widely used in the manufacturing of chemical, fertilizer, petroleum, and medical equipment.