Precautions for daily use of stainless steel flanges

The stainless steel flange connection is easy to use and can withstand greater pressure. In industrial pipelines, flange connections are widely used. 1. In order to prevent the corrosion between the eyes due to the heating of the flange cover, the welding current should not be too large, about 20% less than the carbon steel electrode, the arc should not be too long, the interlayer cooling is fast, and the narrow welding bead is better. 2. The electrode should be kept dry when in use. The titanium-calcium type should be dried at 150℃ for 1 hour, and the low-a hydrogen type should be dried at 200-250℃ for 1 hour to prevent the electrode coating from sticking to oil and other dirt, so as not to increase the weld. The carbon content affects the quality of weldments. 3. When stainless steel flange pipe fittings are welded, carbides are precipitated after repeated heating, which reduces corrosion resistance and mechanical properties. 4. Chromium stainless steel flange pipe fittings have larger hardenability American standard flanges after welding, which is prone to cracks. If the same type of chromium stainless steel electrode is used for welding, preheating above 300°C and slow cooling treatment at about 700°C after welding must be carried out. If the weldment cannot be subjected to post-weld heat treatment, stainless steel flange pipe welding rods should be used. 5. For stainless steel flanges, appropriate amount of stability elements Ti, Nb, Mo, etc. are added to improve corrosion resistance and weldability. The weldability is better than that of chromium stainless steel flanges. When using the same type of chromium stainless steel flange electrode, it should be preheated above 200 ℃ and tempered at about 800 ℃ after welding. If the weldment cannot be heat treated, stainless steel flange pipe welding rods should be used. 6. Stainless steel flange pipe fittings and butt welding flange electrodes have good corrosion resistance and oxidation resistance, and are widely used in chemical, fertilizer, petroleum, and medical machinery manufacturing.