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In September 2021, the price of domestic construction steel rose sharply. By September 29, the steel index closed at 6110 yuan, up 620 yuan from the end of last month.

In September 2021, the price of domestic construction steel rose sharply. By September 29, the steel index closed at 6110 yuan, up 620 yuan from the end of last month.

1, in order to guard against the occurrence of sunny erosion due to heating, welding current should not be too sticky, less than 20% of carbon steel electrode, arc should not be too long, fast cooling between layers, narrow pass is appropriate. 2, stainless steel pipe fittings after welding hardening is sticky, easy to crack. If the acceptance of typical stainless steel pipe fitting welding, it is necessary to carry out more than 300℃ preheating and after welding 700℃ at the mercy of slow cooling disposal. If the weldment cannot be heat disposed after welding, stainless steel tube electrode should be used. 3, stainless steel pipe fittings, in order to improve the corrosion resistance and weldability and add appropriate amount of invariable elements Ti, Nb, Mo, weldability is better than stainless steel pipe fittings. The acceptance of typical chromium stainless steel electrode, should be more than 200℃ preheating and after welding 800℃ temper disposal. If the weldment can not be heat disposed, chromium nickel stainless steel electrode should be used. 4, stainless steel pipe welding rod has exquisite erosion resistance and oxidation resistance, widely used in chemical industry, chemical fertilizer, petroleum, medical machinery manufacturing. 5, stainless steel pipe fitting skin titanium calcium type and low hydrogen type. Titanium-calcium type can be used for AC and DC, but the welding depth is shallow when AC welding, and it is convenient to redness, so the dc power supply is generally accepted.

Stainless steel butt welding tee and elbow is also a class of pipe fittings, stainless steel raw material forged stainless steel pipe fittings, so called stainless steel pipe fittings. The main raw materials of pipe fittings are 304L, 316L, carbon steel, etc. Stainless steel pipe fittings include stainless steel elbow, stainless steel tee, stainless steel reducing pipe, equal diameter pipe fittings, stainless steel pipe cap, etc., which can be divided into four categories according to the connection method of pipe fittings: flange stainless steel pipe fittings, threaded stainless steel pipe fittings, socket stainless steel pipe fittings and welded stainless steel pipe fittings. Stainless steel butt welding elbow is used for the orientation of the pipe head turning place and connection; And stainless steel butt welding tee is used for the intersection of three pipes; Flange thread connection is mainly used in pipes and pipes connected with each other, usually connected with the pipe end, stainless steel four-way pipe installed in the intersection of four pipes at the local; The stainless steel reducing pipe is installed in the direction of connection of two pipes of different diameters. Stainless steel pipe fittings belong to a kind of pipe fittings. Primary stainless steel raw material: 304L, 316, 316L Each product will have two characteristics: strengths and weaknesses. The price of stainless steel pipe fittings is relatively high, stainless steel products are often higher can reflect the value, is the price is a little bad to bear.