Matters needing attention in the use of stainless steel plate flanges

　　The welding current should not be too large, about 20% less than that of carbon steel electrode, the arc should not be too long, and the layers should be cooled quickly, so the narrow bead should be preferred.

　　The electrode should be kept dry when used. The titanium-calcium type should be dried at 150 C for 1 hour, the low a hydrogen type should be dried at 200 - 250 C for 1 hour (can not be repeatedly dried, otherwise the coating is easy to crack and peel), to prevent sticky oil and other dirt from the electrode coating, so as to avoid increasing the carbon content of the weld and affecting the quality of the weldment.

　　When stainless steel plate flange pipe fittings are welded, carbides are precipitated by repeated heating, which reduces corrosion resistance and mechanical properties.

　　The DN900 Stainless Steel Plate Flange after welding are larger than those of American Standard flanges. If the same type of chromium stainless steel electrode (G202, G207) is used for welding, it is necessary to preheat above 300 C and slow cooling treatment around 700 C after welding. If the weldment cannot be heat treated after welding, stainless steel flanged pipe electrode (A107, A207) shall be used.

　　The weldability of stainless steel plate flange is better than that of chromium stainless steel plate flange by adding appropriate stability elements Ti, Nb and Mo to improve corrosion resistance and weldability. When using the same type of chromium stainless steel plate flange electrode (G302, G307), it should be preheated above 200 C and tempered around 800 C after welding. If the weldment can not be heat-treated, stainless steel plate flange pipe fittings (A107, A207) shall be used.

　　Stainless steel plate flange, butt welding flange electrode with good corrosion resistance and oxidation resistance, widely used in chemical, fertilizer, petroleum, medical machinery manufacturing.