Comparison of stainless steel and carbon steel flanges?


Date:

2023-09-28

When using the electrode, it should be boring. 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 (it cannot be dried repeatedly, otherwise the coating is easy to crack and peel off), so as to prevent the coating of the electrode from sticking oil and other dirt, and avoid increasing the carbon content of the weld and affecting the quality of the welded parts. When flange pipe fittings are welded, carbides are separated by repeated heating, which reduces corrosion resistance and mechanical properties. Chrome flange pipe after welding hardening American standard flange is larger, prone to cracks. If the same type of chrome stainless steel electrode (GG207) is used for welding.

1, high electric negative rate, about 5 times that of carbon steel.

2. The large coefficient of linear expansion is 40% larger than that of carbon steel, and with the increase of temperature, the value of linear expansion coefficient also improves accordingly.

Low thermal conductivity, about 1/3 of carbon steel. In order to prevent corrosion between eyes due to heating of flange cover, the welding current should not be too large, about 20% less than that of carbon steel electrode, the arc should not be too long, the interlayer should be quickly cooled, and narrow weld bead is appropriate.

When using the electrode, it should be boring. 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 (it cannot be dried repeatedly, otherwise the coating is easy to crack and peel off), so as to prevent the coating of the electrode from sticking oil and other dirt, and avoid increasing the carbon content of the weld and affecting the quality of the welded parts. When flange pipe fittings are welded, carbides are separated by repeated heating, which reduces corrosion resistance and mechanical properties. Chrome flange pipe after welding hardening American standard flange is larger, prone to cracks. If the same type of chrome stainless steel electrode (GG207) is used for welding.

It is necessary to carry out preheating above 300 ℃ and slow cooling treatment at about 700 ℃ after welding. If the weldment cannot be heat treated after welding, the flange pipe fitting electrode (AA207) should be selected. Flange, in order to improve the corrosion resistance and weldability, and appropriately increase the appropriate amount of stability elements Ti, Nb, Mo, etc., weldability is better than chromium flange.

When selecting the same type of chrome flange welding rod (GG307), it should be preheated above 200 ℃ and tempered at about 800 ℃ after welding. If the weldment cannot be heat treated, the flange pipe fitting electrode (AA207) should be selected. Flange pipe fittings, butt welding flange electrode has good corrosion resistance and oxidation resistance, widely used in chemical industry, chemical fertilizer, petroleum, machinery manufacturing.

Flange is a disc-shaped parts, more common in pipeline engineering, flanges are paired and the use of matching flanges on the valve. In the pipeline engineering, the flange is mainly used for the connection of the pipeline. In the pipeline of demand connection, various devices are a piece of flange.

Preparation before measurement: when measuring, arrange three flanges, two of them to measure. One person proofread and fill in the form. The measuring tool uses vernier caliper. If there is no condition, it can be measured with external caliper and steel ruler. It is a fine work and is the premise of fixture installation. The measurement and record must be prepared correctly. Fill in the form must be careful and clear, in the actual measurement work, to cooperate with each other, stainless steel flange can be in accordance with the correct principle, with and use.

Key words:

Forgings
Flange

Product inquiry