ERW Steel Pipe

　　The 2205 duplex stainless steel is formed by reducing the nickel content to about 5% and adjusting the addition amount of manganese and nitrogen to form ferrite of about 40-50%. The chemical composition of 2205 duplex stainless steel is balanced, so that the austenitic phase and the ferrite phase have large and appropriate corrosion resistance. "Biphasic" refers to a microscopic arrangement having two phases of austenite/ferrite. 　　The addition of nitrogen content of 2205 duplex stainless steel and its fine grain microstructure make it have higher strength than common austenitic stainless steels such as 304L and 316L. Under solid solution annealing conditions, the 2205 duplex stainless steel has a yield strength that is approximately twice that of 316L stainless steel. Due to this higher strength, the allowable stress of 2205 duplex stainless steel can be much higher, depending on the design specifications chosen for process equipment manufacturing. In many applications, ...

　　ERW straight seam welded pipe surface quenching and tempering heat treatment is usually carried out by induction heating or flame heating. The main technical parameters are surface hardness, local hardness and effective hardened layer depth. The hardness test may be performed by a Vickers hardness tester or a Rockwell or surface Rockwell hardness tester. The choice of test force (scale) is related to the effective hardened layer depth and the surface hardness of the straight seam welded pipe. There are three hardness testers involved here. 　　Vickers hardness tester is an important means to test the surface hardness of heat-treated straight seam welded pipe. It can test the surface hardened layer as thin as 0.05mm thick with the test force of 0.5-100kg. It has the highest precision and can distinguish the surface of heat-treated workpiece. A small difference in hardness. In addition, the effective hardened layer depth is also measured by a Vickers hardness tester. Therefore, it is n...

　　201 stainless steel features: 　　201 stainless steel contains less nickel, less chromium, weaker anti-corrosion performance, more manganese, acid and alkali resistance, and cheap! Used for decorative pipes and industrial pipes. 　　304 stainless steel features: 　　304 stainless steel contains nickel, more chromium, good corrosion resistance, high toughness and high price! Used in anti-corrosion buildings. 　　The difference between 201 stainless steel and 304 stainless steel is as follows: 　　1. Different chemical composition: Generally, stainless steel is added with metal elements such as nickel, chromium and manganese on the basis of iron and carbon to make it have anti-rust properties. 304 stainless steel contains more nickel and chromium than 201 stainless steel, and manganese ratio 201 stainless steel is less. 　　2. Chemical properties: Nickel-chromium metal mainly plays a role in corrosion resistance. 304 stainless steel contains more nickel and chromium, and its corrosion...

　　Nickel-iron alloy is the first alloy composed of nickel metal and iron for material exercise. The front part of nickel-iron alloy is alloy, not only the outer layer. The primary component of the nickel-iron alloy is nickel and iron, and further contains impurity elements such as Cr, Si, S, P, and C. 　　The primary effect of nickel in stainless steel is that it changes the crystal structure of the steel. One of the fundamental reasons for adding nickel to stainless steel is to form an austenitic crystal structure and then to improve the characteristics of stainless steel such as plasticity, weldability and resistance, so nickel is called an austenite constituent. 　　The nickel content of up to 5% can increase the tensile strength and hardness of the attapulgite carbon structural steel. Containing 3% nickel in carbon steel improves its tensile strength, impact resistance, yield point and deformation. 　　What is nickel-iron alloy? Nickel is a yellowish silvery white metal that is a ...

　　What steel is resistant to high temperatures? The variety of steel is complicated, but the function is not exactly the same. Generally, we call the high temperature resistant steels "heat resistant steel". Heat-resistant steel is a type of steel that has oxidation resistance and high temperature strength and excellent heat resistance under high temperature conditions. 　　Heat-resistant steel is commonly used in the manufacture of components operating at high temperatures in industrial sectors such as boilers, steam turbines, power machinery, industrial furnaces, and aerospace and petrochemical industries. In addition to high temperature strength and high temperature oxidation resistance, these parts require satisfactory resistance, excellent workability and weldability, and certain arrangement stability depending on the application. 　　Heat-resistant steel can be divided into two types according to its function: anti-oxidation steel and heat-strength steel. Anti-oxidation...

　　Welded steel pipes can be roughly divided into three categories according to the molding process: 　　First, electric resistance welded steel pipe 　　ERW (Electric resistance welded Pipe), the weld type is straight seam. Resistance welding uses a pressure-welding method without filler metal. The weld is not filled with other components. The skin effect and the proximity effect of the high-frequency current cause the edge of the plate to be instantaneously heated to the welding temperature, and extruded by a squeeze roll to form a forging. The weld of the tissue. 　　Electric resistance welded steel pipes can be further divided into two types: HFW (High Frequency Welding Pipe) and LFW (Low frequency welding). 　　 ERW steel pipe is mainly used to transport vapor and liquid objects such as oil and natural gas, and can meet various requirements of high and low pressure. At present, it plays an important role in the world of transportation pipes. 　　Second, spiral welded steel pipe ...

　　Cold drawn erw pipe, which is one of the best choices for the production of multi-stage hydraulic cylinders. Its process is the same as that of precision seamless pipe cold drawing. It is precision drawn by precision resistance welding (ERW) and manufactured with EN. 10305-2 EU mechanical cold drawn carbon steel welded pipe standard. 　　After the electric resistance welded pipe is welded, the whole pipe body is normalized to ensure the homogeneity of the weld and the heat affected zone with the rest of the metallographic structure and mechanical properties; cold drawing and subsequent heat treatment (eliminating internal stress) and the steel pipe have good dimensions. And mechanical properties. 　　After the welded steel pipe is processed by cold drawing and deep processing, a high-quality steel pipe with small dimensional tolerance and good mechanical properties is obtained. 　　In addition, cold drawn welded pipes have significant advantages over cold drawn seamless pipes in ter...

　　Reasons for cracks in seamless steel pipes: 　　1. The crack traverses the thickness direction of the slab. The crack in the central equiaxed grain region is a curved fine crack along the grain boundary. The crack on the inner arc side is generally a straight crack in the crack, and the crack on the outer arc side is generally along the crystal crack. 　　2. The crack along the grain boundary is a stress crack, and the crack is a crack that breaks through the grain and is the result of external force. 　　What do you need to do to resolve this crack? 　　1. Improve the accuracy of the arc of the casting machine, avoid excessive stress on the solid-liquid interface at the initial stage of solidification, and prevent cracks along the grain boundary. 　　2. Forced cooling is achieved by appropriately increasing the casting speed and increasing the amount of cooling water, increasing the water flow rate, and lowering the water temperature within a certain range. 　　3. Strictly control t...

　　J55 casing pipe is an important equipment for oil drilling. Its main equipment also includes drill pipe, core pipe and casing, drill collar and steel pipe for small diameter drilling. 　　J55 oil casing specifications are mainly 139.7*7.72, 177.8*9.19, 244.5*8.94, 244.5*10.03, 244.5*11.05, etc. 　　J55 oil casing-API has three lengths: R-1 is 4.88 ~ 7.62m, R-2 is 7.62 ~ 10.36m, and R-3 is 10.36m to longer. Some imported goods are marked with the word LTC, namely the filament sleeve. In addition to adopting API standards, there are a small number of Japanese factory standards imported from Japan. 　　Commonly used casing steel grades are DZ40, DZ55, DZ753. 　　According to SY/T6194-96. The tube and its couplings are of the same steel grade. Sulfur content <0.045%, phosphorus content <0.045%. 　　Take chemical analysis samples according to the provisions of GB222-84. Chemical analysis was carried out in accordance with the relevant provisions of GB223. 　　According to the Americ...

　　The welded square tube is a hollow square section steel square tube, also known as a hollow cold-formed steel. The utility model relates to a profiled steel of a square cross-sectional shape which is formed by hot-rolling or cold-rolling strip or coil as a blank after cold bending forming and then high-frequency welding. In addition to the thickening of the wall thickness of the seamless square tube, the corner size and the straightness of the edge meet or exceed the level of the cold-formed square tube of the electric resistance welding. The size of the R angle is generally between 2 and 3 times the wall thickness. . It is also possible to produce R-square squares of the size required by the customer according to the needs of the customer. The general length is 6 meters. The welded steel pipe has simple production process, high production efficiency, many varieties and specifications, and low equipment investment, but the general strength is lower than that of seamless steel pipe. ...