LSAW Steel Pipe

　　 SSAW steel pipe in the production process, we need to pay attention to a series of matters. Except the following test items, according to the API standard and other relevant standards and the special requirements of some users, the destructive tests for steel, steel pipe is needed, including physical and chemical properties of the raw materials into the plant sampling, visual inspection of 100% steel . 　　A. Oiled marking: steel after passing were oiled to prevent corrosion, and according to user requirements for marking. 　　B. Leveling Milling: The flat steel anvil machine so that the original curl, and then through the edge milling machine for two-sided steel milling, so as to meet the requirements of the plate width, plate edge parallelism and groove shape. 　　C. Shear molding: the steel plate production line along the outer edge of the spiral curl into a tube. 　　D. Butt cut: double-sided submerged arc welding using advanced technology to pre-welding, internal welding, outs...

　　The first thing to consider about carbon steel pipe is simply what it is. Carbon steel pipe is pipe comprised of carbon steel. But what is carbon steel? Here’s how the American Iron and Steel Institute defines it: 　　Steel is considered to be carbon steel when no minimum content is specified or required for chromium, cobalt, niobium, molybdenum, nickel, titanium, tungsten, vanadium or zirconium, or any other element to be added to obtain a desired alloying effect; when the specified minimum for copper does not exceed 0.40 percent; or when the maximum content specified for any of the following elements does not exceed the percentages noted: manganese 1.65, silicon 0.60, copper 0.60. 　　Simply, carbon steel is steel in which the main alloying component is carbon. Interestingly, most of the world’s steel falls into this category. 　　What are the different types of carbon steel pipe? 　　Carbon steel is classified according to how much carbon has been mixed with the base element, iro...

　　 Galvanized pipe is pipe that has been coated with a layer of zinc. This coating protects the pipe from corrosion and rust, leading to increased longevity and enhanced reliability. 　　The zinc is often applied via a hot-dipping process, literally lowering the intended material—whether it is steel, aluminum or another metal—into hot zinc. This coating protects the pipe by corroding first when the pipe is out in the field, allowing the metal underneath it to stay intact and usable for a longer period of time. 　　Here are a handful of great reasons why you should choose galvanized pipes: 　　 Inexpensive Protection 　　Galvanization is often less expensive than other ways of protecting metal from corrosion. This is due to the fact that other methods often require intensive labor. Labor costs have risen steadily, which means the costs of these methods have risen as well. 　 　ASTM Galvanized Pipe Standardization 　　The ASTM has standards for many different types of galvanized pipes. ...

　　The seamless steel pipe and the welded steel pipe have a weld bead on the inner wall of the welded pipe, and are seamless. 　　The seamless pipe pressure is higher, the welded pipe is generally about 10 MPa, and now the welded pipe has been seamlessly processed. Seamless steel tubes are formed at one time during rolling. 　　Welded steel pipes need to be welded after rolling, generally with spiral welding and straight welding.The performance seamless tube is better, and of course the price is higher. The seamless steel pipe is formed by perforating a steel ingot or a solid tube blank, and then hot rolled, cold rolled or cold drawn. The seamless steel pipe has a hollow section and is used in a large amount as a pipe for conveying fluid. A welded pipe is a steel pipe which is welded and deformed into a round shape by a steel strip or a steel plate and has a joint on the surface. The blank used for the welded pipe is steel plate or strip. 　　Identification method: look inside the pipe,...

　　 Carbon steel pipe is one of the most popular piping materials in the world. And for good reason: it has many advantageous characteristics. 　　Let’s take a look at some of those characteristics and the applications that they make carbon pipe particularly well suited for. 　　Shock Resistance 　　Carbon pipes have a tremendous ability to withstand shocks and vibrations. While other materials may succumb in such environments, carbon pipes are able to maintain their integrity and performance in even the most jarring conditions. 　　This makes carbon pipes and welded carbon pipes particularly useful in the transportation industry. Pipes laid under roadways can experience extreme shocks and vibrations from the heavy traffic above. Carbon pipe, with its ability to withstand shock, is a great choice for such situations. 　　Tensile Strength 　　Carbon steel can endure very high pressures. This gives carbon pipes an excellent carrying capacity, meaning that, pound for pound, they can carry...

　　1, According to the production method of cs steel pipe classification 　　(1) seamless steel pipe is including the hot-rolled pipes, cold-rolled, cold drawn tubes, extruded tube 　　(2) welded steel pipe 　　(A) according to process, there are arc welded pipe, ERW pipe (high-frequency, low frequency), gas pipe, stove pipe 　　(B) by weld points, there are longitudinally welded pipes and spiral welded pipe 　　2, According to the cross-sectional shape classification 　　(1) simple section steel, there are round pipe, square pipe, oval pipe, steel triangular, hexagonal steel, diamond steel, octagonal steel, steel semi-circle, the other. 　　(2) complex section steel, there are equilateral hexagonal steel pipe, five plum-shaped steel pipe, steel pipe double convex, double concave steel, oval-shaped steel conical pipe, corrugated steel pipe, steel pipe case, other. 　　3, According to wall thickness, there are thin-walled steel pipe, thick-walled steel pipe 　　4. By Application, there ...

　　 Durability 　　Steel is one of the most popular types of pipe fittings and has been used for construction of pipes and pipe fittings for years because of its durability and strength. However, carbon steel, or plain-carbon steel, has the ability become much stronger through heat treatment. The more carbon added to the steel, the stronger it can become, which is why it is considered one of the strongest types of steel. Another way to increase the durability is to create a harder surface by adding a layer of chromium. Chrome plated pipe fittings are not only durable, but prevent corrosion and may also make the cleaning process much easier. 　 　Multi-purpose 　　 Carbon steel pipe fittings are typically used for industrial purposes such as commercial construction, electric-power, petroleum refinement and the building of ships, but are also often seen in the household. They are used for fire sprinkler systems and pipes carrying water, types of flammable gasses, oil or steam. Because of...

　　20# Precision tube is a kind of high-precision steel pipe material after cold drawing or hot rolling. Because the inner and outer walls of 20# precision steel pipe have no oxide layer, high pressure and no leakage, high precision, high smoothness, no deformation of cold bending, flaring, flattening without cracks, etc., it is mainly used to produce pneumatic or hydraulic components, such as The cylinder or cylinder can be a seamless tube or a welded tube. The chemical composition of the precision steel pipe includes carbon C, silicon Si, manganese Mn, sulfur S, phosphorus P, and chromium Cr. 　　The difference between 20# precision tube and seamless steel tube 　　1. The main feature of seamless steel pipe is that it has no welded joint and can withstand large pressure. The product can be a very rough cast or cold-draw. 　　2. Precision steel pipes are products that have appeared in recent years, mainly due to strict tolerances and roughness of inner and outer wall sizes. 　　20# pr...

　　Classification of 3087 seamless steel tubes: seamless steel tubes are divided into hot rolling and cold rolling seamless steel tubes. 　　Hot-rolled seamless steel pipes are divided into general steel pipes, low and medium pressure boiler steel pipes, high pressure boiler steel pipes, alloy steel pipes, stainless steel pipes, petroleum cracking pipes, geological steel pipes and other steel pipes. 　　Cold-rolled seamless steel pipe is divided into general steel pipe, low and medium pressure boiler steel pipe, high pressure boiler steel pipe, alloy steel pipe, stainless steel pipe, petroleum cracking pipe, other steel pipes, and also includes carbon thin-walled steel pipe and alloy thin-walled steel pipe. Stainless steel thin-walled steel pipe and special-shaped steel pipe. The outer diameter of the hot-rolled seamless pipe is generally larger than 32mm, the wall thickness is 2.5-75mm, the diameter of the cold-rolled seamless steel pipe can be 6mm, the wall thickness can be 0.25mm, th...

　　Standard martensitic stainless steels are: 403 stainless steel, 410 stainless steel, 414 stainless steel, 416 stainless steel, 416 (Se stainless steel), 420 stainless steel, 431 stainless steel, 440A stainless steel, 440B stainless steel and 440C stainless steel. The corrosion resistance of these steels comes from "chromium". "The chromium content ranges from 11.5 to 18%. The higher the chromium content, the higher the carbon content of the steel to ensure the formation of martensite during heat treatment. The above three types of 440 stainless steel are rarely considered to be welded. Application, and the filler metal of the 440 type component is not easy to obtain. 　　Martensitic stainless steel is mainly low carbon or high carbon steel with a chromium content ranging from 12% to 18%. There are three types of martensitic stainless steel grades as follows: 　　1. Low carbon and medium carbon 13% Cr steel. 　　2. High carbon 18% Cr steel. 　　3. Low carbon nickel (ab...

　　Decarburization is a phenomenon in which the surface carbon content of a steel pipe is lowered during heat treatment. The essence of decarburization is that carbon atoms in steel pipes react with furnace atmospheres such as hydrogen or oxygen at high temperatures to form methane or carbon monoxide. 　　Decarburization is the result of interdiffusion between atoms during heat treatment. On the one hand, oxygen diffuses into the steel; on the other hand, the carbon in the steel diffuses outward. The decarburization layer can be formed only when the decarburization rate exceeds the oxidation rate. When the oxidation rate is large, the obvious decarburization phenomenon may not occur, that is, the iron is oxidized to form an oxide scale after the decarburization layer is produced. Therefore, in an atmosphere in which oxidation is relatively weak, a deep decarburization layer can be formed. 　　The decarburization layer of the steel pipe includes a full decarburization layer and a partial...

　　High frequency straight seam welded steel pipe welding quality defects are cracks, welding, water leakage, scratches and so on. 　 　First, cracks 　　Fracture is the main defect of welded pipe , its manifestation can be by the usual cracks, local periodic cracks, irregular intermittent cracks. Some of the steel pipe after welding surface without cracks, but by the flattening, straightening or hydrostatic test cracks. Severe leakage will leak. There are many causes of cracks. Elimination of cracks is one of the most difficult problems in welding adjustment operations. 　 　Second, take the welding 　　Lap welding is the edge of the tube in the welding when the dislocation, although the curette can still see the traces of dislocation. 　　1) Molding quality is not good. Forming the edge of the tube is not usually appear on both sides of the usual lap welding, forming the edge of the wave and the drum package, the local small lap. 　　2) The production of thin-walled tube, the squeeze ...

　 　1, Tube heating 　　The average heating to stop the rapid rise and fall of temperature. To adhere to a smooth landing every time the temperature slowly, the temperature does not exceed the maximum landing 30 ℃. 　　2, Mandrel mill 　　The average wall thickness of the thick-walled tubes and solid billets, so that the probability of a significant reduction in the mandrel bending deformation, can be useful for the progress of the wall thickness precision steel pipe . 　　 3, Precision of the mandrel 　　Mandrel outer precision control at ± 0.1mm, straight degrees mandrel deflection does not exceed 5mm. Welding, finishing pierce a pin positioned between two sections of the mandrel, in order to avoid the formation of solder total straightness deviation is too large. 　　 4, Perfect process 　　Perfect process, to avoid the center and pull the thin wall thickness by Haou transcend the limitations of the control condition seizures, progressive wall thickness accuracy. 　 　5, Centering ro...

　　Surface NDT methods of straight seam steel selection principles: magnetic iron pipe should be used in magnetic particle testing; non-ferromagnetic steel should be used in penetration testing. Delayed cracking tendency of welded joints, the surface should be non-destructive testing after welding cooling certain time; reheat cracking tendency of welded joints, the surface should be in non-destructive testing and post-weld heat treatment once each. 　　Surface non-destructive testing applications in accordance with the standard requirements: 　　(1) An outer surface of the tube material quality inspection. 　　(2) Important butt weld surface defect detection. 　　(3) Important fillet surface defect detection. 　　(4) Important socket weld and jumper tee branch pipe defect detection. 　　(5) Pipe bending surface defect detection. 　　(6) The material tends to quench detection larger groove welded joints. 　　(7) The design temperature is below zero or non-austenitic stainless steel pipe ...

　　 Line pipe used plates 60 to 70 years using the Anshan Iron and Steel and other major manufacturers A3,16Mn, with diameter pipeline delivery pressure increases and progress strength steel can not meet demand. 80 years after each oil pipe plant started by the United States API standard production pipeline steel, because of the domestic pipeline board manufacturing plant immature technology, mainly imported plate. Enter the 1990s, the domestic plate production line developed rapidly, Baosteel, Wuhan Iron and Steel, Anshan, Benxi Iron and Steel, Panzhihua Iron and Steel and other enterprises have developed and produced a series of high-grade steel X pipeline. 　　In the domestic pipeline steel production process are: a conventional semi-continuous hot rolling, CSP continuous casting and rolling, plate units, Steckel unit. 　　1) Semi-continuous rolling mill: Includes 1 rack 5 rack Steckel mill and finishing mill. In the semi-continuous rolling mills, strip the finish rolling experience...