You don't necessarily know little about stainless steel pipes.

2018-11-15 19:35:02

You don't necessarily know little about stainless steel pipes.

1, stainless steel plate weight formula: length * width * thickness = weight = weight

For example, 1.5mm*1000mm*2000mm, 1*2*1.5*7.93=23.79 kg.

2, stainless steel tube weight formula: (diameter wall thickness) * wall thickness * weight = m weight

For example: 108*4mm tube, (108-4) *4*0.02491=10.36 kg

3, what is the difference between stainless steel tube 304 and 201?

First, the price is different: 304 the quality is better, but the price is high, the 201 is worse, but the price is cheaper.

Two, the composition is different: 304 is 8 nickel, 18 chromium, 201 is 1 nickel, 13 chromium.

Three, rust proof properties are different: 304 rust proof performance is strong, 201 rust proof performance is weak.

4. Different strength: yield point 205 MP of 304 steel is greater than 515 Mpa, yield point 275 MPa of 201 steel and tensile strength is greater than 520 MPa.

5. Why does stainless steel rust?

First, many people think stainless steel pipes will not rust. This is a wrong one-sided view. First of all, stainless steel pipes are stainless and corrosion-resistant. Stainless steel pipes are not rusted in weak corrosive environment such as atmosphere and fresh water, and the chromium content in the steel must be more than 12%. If the chromium content is low or not used in weak corrosion environment such as atmosphere (including in weak corrosion environment such as atmosphere, but under the condition of Cl-local enrichment and concentration), rust will occur. Acid-resistant steel pipes are corrosion-resistant steel pipes in acid, alkali, salt and other strong corrosive media, but they are also corrosion-resistant under certain conditions, such as medium type, temperature, concentration, impurity content, flow rate, pressure and so on. There are no stainless steel pipes that are rusty and corrosion-resistant in all the world.

2. Stainless steel surface accumulates dust containing other metal elements or adhesives of different metal particles. In humid air, the adhesives and the condensate water between the adhesives and stainless steel connect the two into a micro-battery, which leads to electrochemical reaction, and the protective film is destroyed. It is called electrochemical corrosion.

3. The surface of stainless steel adheres to organic juice (such as melon and vegetable, noodle soup and phlegm). Under the condition of water and oxygen, organic acid is formed, and for a long time, organic acid corrodes the metal surface.

4. The adhesion of stainless steel surface containing acid, alkali and salts (such as alkali water and lime water spraying on decoration walls) causes local corrosion.

5. In polluted air (containing a large number of sulfides, oxides and hydrogen oxides), when condensed water, it forms nitric acid and acetic acid liquid point, which causes chemical corrosion.

4. The difference between intermediate frequency furnace and refining furnace for stainless steel is:

First, if the waste metal is smelted in the furnace, alternating magnetic field is generated by alternating current, and alternating induction potential and current are generated inside the metal in the alternating magnetic field. The direction of induction current is opposite to that of the current in the induction coil of the furnace. Under the action of induction electromotive force, the heated metal generates induction current. When the current of stainless steel plate passes through, it generates heat to overcome the resistance of metal. The intermediate frequency furnace uses this heat to melt and heat the metal so as to achieve the goal of melting. Medium frequency furnaces can only be produced once, especially in raw materials. Therefore, the 321 stainless steel plate is usually smelted by stainless steel scrap and iron sand. This smelting method can not control the content of certain elements, so the product quality is relatively inferior, generally not used for deep processing and other products industry.

2. Refining furnace is raw ore smelting, commonly known as AOD refining furnace, which injects inert gas (Ar, N2) into molten steel while blowing oxygen at standard atmospheric pressure. By reducing partial pressure of CO, it achieves the effect of false vacuum, thus reducing carbon content to a very low level and inhibiting the oxidation of chromium in steel. It is suitable for the production of low carbon and ultra-low carbon stainless steel. It is easy to control the S content in special steel below 0.005%. AOD refining furnace can carry out secondary steelmaking, in order to achieve refining purpose, it can add or reduce related elements flexibly. In the process of steelmaking, scrap iron and iron sand are generally used for steelmaking. The quality of products is relatively high and the ductility is good. 321 stainless steel sheet is generally smelted in refining furnace for deep drawing products.

Three: medium frequency furnace is unstable and easy to rust, and the quality of refining furnace is not easy to rust.

Four: element distinction: medium frequency furnace carbon content C 0.1% above, refining furnace carbon content C is below 0.1%.