Stainless steel flanges are widely used in the petroleum industry, water and natural gas pipelines, from most corresponding pressures. This kind of thin bellows is generally welded process, because it is too thin, about 0.2 mm, difficult to weld process.
Welded stainless steel flange
The welding process includes welding, brazing, etc. The arc welding process of stainless steel flanges or other pipelines means that the arc can not directly point to the bellows, but is arc hot melt welding on the bellows.
The required materials should be prepared before the welding is performed. Remove oil and other dirt from stainless steel corrugated flange.
Assuming the welding process flange and leakage, the original welding process scars should be eliminated, the straight pipe of the flange should be polished and polished metal luster, the straight pipe of the bellows is too thin and can not be polished, ground and cleaned, and the light should be polished and polished with a manual emery cloth.
It is essential for the arc to travel through the flange tube. The arc refers to a very thick pipeline, the arc flame is used to heat the bellows, the edge of the bellows is blocked with welding wire, and the stainless steel welding wire is dissolved. Should be welded process thick wall pipe, select short welding or spot welding. In the welding process, the melting standard of the bellows should be consulted at any time.
Under normal circumstances, 1 time should melt 1 or 3 molten pools, so it is not suitable for 1 time 1 welding process. Especially in the case of large open space, it is very easy to burn through.
Pay attention to the processing points
When the stainless steel flange is welded, carbides will be precipitated by repeated heating, and the refracted carbides will reduce corrosion resistance and mechanical properties. Therefore, when welding stainless steel elbows, do not repeat heating to prevent carbides from affecting the corrosion resistance and mechanical properties of stainless steel elbows.
In order to prevent the corrosion between the eyes due to heating, the welding current should not be too large when welding stainless steel elbows, about 20% less than carbon steel welding rods, the arc should not be too long, the interlayer fast cooling, and the narrow weld pass is appropriate.
Therefore, when welding with stainless steel elbow electrode, it is necessary to reasonably control the welding current to prevent excessive current from producing eye corrosion, affecting the welding quality of stainless steel elbow. Considering its safety and service life, the focus is on improving the toughness, impact resistance, and wear resistance of the pipe lining
