What should be paid attention to when welding stainless steel cross?

　　1. In order to prevent eye to eye erosion due to heating, the welding current should not be too large, 20% less than that of carbon steel electrode, the arc should not be too long, the interlayer should be cooled quickly, and the narrow weld bead is suitable.

　　2. Stainless steel cross has great hardenability after welding, which is easy to crack. If welding with typical stainless steel cross is accepted, it is necessary to preheat above 300 ℃ and slow cool at 700 ℃ after welding. If the weldment can not be heat treated after welding, stainless steel pipe electrode should be selected.

　　3. The weldability of stainless steel cross is better than that of stainless steel cross by adding some invariable elements such as Ti, Nb and Mo to improve the corrosion resistance and weldability. When using the same typical chromium stainless steel electrode, it should be preheated above 200 ℃ and tempered at 800 ℃ after welding. If the weldment can not be heat treated, chromium nickel stainless steel electrode should be used.

　　4. Stainless steel cross has excellent corrosion resistance and oxidation resistance, which is widely used in chemical industry, chemical fertilizer, petroleum, medical machinery manufacturing.

　　5. The coating of stainless steel cross has titanium calcium type and low hydrogen type. Titanium calcium type can be used for AC and DC welding, but the penetration of AC welding is shallow, and it is convenient for reddening, so the DC power supply is generally accepted.

　　6. Stainless steel cross have certain functions of corrosion resistance, heat resistance and wear resistance. Generally used for power station, chemical industry, petroleum and other equipment materials. The weldability of stainless steel pipe is poor, so we should pay attention to the welding process and choose the right electrode before heat treatment.

　　7. The welding rod shall be kept dry during operation. The titanium calcium type shall be dried at 150 ℃ for 1 hour, and the low hydrogen type shall be dried at 200-250 ℃ for 1 hour. The coating of welding rod shall be free of oil and other dirt, so as not to add carbon content to the weld and affect the quality of weldment.

　　8. When stainless steel cross is welded, carbide precipitates when heated repeatedly, which reduces corrosion resistance and mechanical function.