steel pipe

　　The API 5CT standard covers seamless and welded casing and tubing pipes for oil and gas transportation. Casing pipes are available in the following materials: H-40, J-55, K-55, N-80, L-80, C-90,T-95 ,P-110, Q-125. 　　Depending on the different condition and depth of the well, we use the different steel grades. The casing is required anti-corrosion under the corrosive environment. In the case of complex geological conditions, the casing has to be resistant to collapse. Most casing steel grades have the same chemical composition. What makes grade different is the heat treatment applied. Casing grades mainly differ in their yield strength, tensile strength, and hardness. 　　According to API 5CT, there are four groups of products to API SPEC 5CT is applicable include the following grades of pipe: 　　Group 1: Grades H, J, K,M, N and R; 　　Group 2: Grades C, L and T; 　　Group 3: Grade P; 　　Group 4: Grade Q. 　　Additional tests required by API 5CT for certain groups of casing make ...

　　Test methods for spiral submerged arc welding pipe 　　Metallographic Metallographic method (or etching method) is polished bead cross-section, showing the inside and outside weld bead after welding performed partial measurement method. Showing that the method can be intuitively apparent bead offset, which can easily be welded deviating measurements. Metallographic welding deviating measurements each pipe manufacturers actually used, and can be summarized in three centerline method, arc deviation method and ridge line method. 　　Centerline on the sampling method can block containing bead, polished bead profile, weld deviating measured under an optical microscope; you can also use 5% (by volume) in the steel pipe end flat after nital wipe containing welding Road site, clearly show the weld bead after partial measurement. Inside, from the outside bead toe is the welding wire centerline partial amount. 　　The method generally arc deviation method after welding shop inspection post or ...

　　The high pressure boiler pipe is a kind of boiler pipe and belongs to the seamless steel pipe , which is mainly used for manufacturing the superheater tube, the reheater tube, the gas-guide tube and the main steam pipe for high pressure and superhigh pressure boilers. Manufacturing processes of high pressure boiler pipes include fine drawing processes, brighting processes, hot rolling processes, cold drawing processes and hot expanding processes. 　 　1. An overview of the high pressure boiler pipe 　　(1) Manufacturing methods 　　High pressure boiler pipes have the same manufacturing methods as seamless pipes, but they have strict grade requirements of steel which steel pipes are made of. High pressure boiler pipes are divided into general boiler pipes and high pressure boiler pipes two categories based on high or low operating temperature. 　　① Operating temperatures of general boiler pipes are below 450℃. Chinese general boiler pipes are mainly made of NO.10 and NO. 20 carbon st...

　　Welded pipe is generally divided into straight seam welded pipe and spiral welded pipe two types. 　 　Strength characteristics 　　When the pressure in the pipe withstand, usually two main stress on the wall, that the radial and axial stress stress δ. Synthetic weld stress δ, where α is the helix angle of the spiral weld pipe. Spiral welded seam degree helix angle is generally so synthetic, and spiral weld Longitudinal stress is the main stress. Under the same operating pressure, spiral pipe of the same diameter than the Longitudinal wall thickness can be reduced. 　　 Hydrostatic burst strength 　　By the relevant comparison test to verify the spiral welded pipe and Longitudinal yield pressure and burst pressure measured and theoretical values ??match, the deviation closer. But whether it is the yield stress or burst pressure, were lower than the Longitudinal spiral welded. Burst test also shows that the rate of deformation ring spiral welded pipe bursting Longitudinal significant...

　　Alloy steels are what they sound like: Steels that include specified amounts of alloying elements. Generally, alloying elements make steels stronger and more resistant to impact or stress. While the most common alloying elements include nickel, chromium, molybdenum, manganese, silicon and copper, many others are used in the production of steel. 　　There are countless combinations of alloys and concentrations in use in industry, with each combination designed to achieve specific qualities. 　　High-alloy types of steel are favored in the piping industry for service in extreme conditions, whether it be in hot or cold conditions or subject to rough use. That’s because the combination of chemistry and proper heat treating can yield strong yet ductile pipe that can take a beating. The oil & gas and power generation industries often favor alloy pipe due to its toughness. 　　Alloying elements also impart increased corrosion resistance to steel pipe. That makes it a leading choice for ...

　　 Alloy steel pipe is a kind of seamless steel pipe, its performance is much higher than the general seamless steel pipe , because this steel pipe inside containing Cr, high temperature resistance, low temperature, corrosion-resistant performance of other non-pipe joints not match, so the more extensive use of alloy tube in the petroleum, aerospace, chemical, electric power, boiler, military, and other industries. 　　The main use of alloy steel pipe used in power plants, nuclear power, high-pressure boiler, high temperature superheater and re-heater high pressure and high temperature piping and equipment, it is made ??of high quality carbon steel, alloy structural steel and heat-resistant stainless steel material, hot-rolled (extrusion, expansion) or cold-rolled (pull) made??. 　　The biggest advantages of alloy steel pipe 　　Can be 100% recycled, environmentally friendly, energy-saving, resource conservation, national strategy, national policy to encourage the expansion of the fie...

　　Ultrasonic detector gas leak detection system is different from the specific design of the sensor to sense that it is limited to a specific gas, but rather to detect sound. 　　Ultrasonic focusing on industrial leak detection, leak detection and predictive maintenance, products and solutions in steel and non-ferrous metals, tobacco and food and beverage, automotive, chemical and oil and gas, mining and cement, glass manufacturing, electricity and cleaning system, military, paper and printing, rail transport, water treatment, infrastructure, subway fan and large air conditioning systems, port automation, and many other industries are widely used. 　　Any gas leakage through holes will generate eddy currents, ultrasound will be part of the band, making the ultrasonic detector leak detection system capable of sensing any kind of gas leak. Drawing process of precision seamless tube with a detection system scan, you can hear the sound from the headphones leak or see changes in the digita...

　　Small diameter high-pressure boiler tube surface defects that affect the quality, mainly due to waste generation. 　　Boiler pipes often in high temperature and high pressure work, pipe smoke and water at high temperature steam oxidation and corrosion effects will occur, thus requiring durable steel with high strength, high oxidation resistance, and good organizational stability, high pressure boiler tube in addition to chemical composition and mechanical properties, hydrostatic testing done by the root, to be flaring, flattening test. Steel to heat treatment delivery. In addition, the finished steel microstructure, grain size, there are certain requirements decarburization. 　　High-pressure boiler tubes are seamless steel pipe categories. Seamless same manufacturing method, but used in the manufacture of steel pipe, there are strict requirements. Often in high-pressure boiler tubes at high temperature and pressure conditions of use, the tube under the effect of high temperature ga...

　　Inner fold of hot rolled seamless steel pipe refers to spiral rendered in the steel pipe inner surface, the semi-helical or irregular distribution of the zigzag folding, some rendered as linear warping. Below are details: 　　1.An inner flap: presenting a straight line, a spiral or a semi-helical sawtooth defect on the inner surface of the steel pipe. 　　2. Inside scarring: scars in the steel pipe inner surface, generally easily peel off. 　　3. Warping: a straight line or intermittent small nail-like tilt leather. Often seen in the capillary head, and easy to peel. 　　4. Inside straights: a straight shape scratch with a certain width and depth. 　　5. Inner edge: a straight shape protrusion with a certain width and depth. 　　6. Inner drum kits: a super and regular protrusion and outer surface is not damaged. 　　7. Pull pits: a regular or non-regular pit and the outer surface without damage. 　　8. Internal thread (this defect produced only at Accel units): spiral traces often s...

　　The first aspect is that galvanized pipes have their own advantages in terms of their convenience. We also know that for users, when they use a product, the first thing is to make it very convenient. It has its own lightest weight, so it can be used on its own to give it a high advantage. 　　And it's on its own convenience, it is also reflected in its installation, because it has a good design on the installation, so it can make it very convenient when it is used by itself, for the user There is also a requirement in this respect. Then there is a user who can use it to achieve a good performance on his or her own service life. For the user, when using a product, it is hot. Galvanized greenhouse pipes have high requirements on their own service life. 　　Because the hot-dip galvanized greenhouse pipe is galvanized, it can achieve a high service life when it is used. If it is made of ordinary carbon steel pipe, it is prone to its own rust performance. If the user uses this product...

　　Petroleum asphalt, raw materials wide, low prices. However, poor working conditions, difficult to guarantee quality, serious environmental pollution. 　　Coal tar epoxy, easy to operate, but a long time covering layer is cured by environmental impact, suitable for field work, the following 10 ℃ difficult construction. 　　Anticorrosive cold tapes, easy to operate, but slightly worse adhesion, low water resistance, low intensity, the large environmental impact. 　　Epoxy powder corrosion, electrostatic spraying, anti-corrosion material with the same kind of tube frit good, strong bonding, epoxy powder but water is poor (high water absorption, reaching 0.83%), to cathodic protection design bring some difficulties. Site appliance requirements, the operation is difficult, difficult to control quality. 　　3PE shrink materials, sealing strong pipeline corrosion, high mechanical strength, water resistance strong, stable quality, convenient construction, applicability, and do not pollute th...

　　The seamless steel tube manufacturing process begins with a solid round billet. The billet is then heated to a high temperature and stretched and stretched until it becomes the shape of a hollow tube. 　　Steel pipes are ubiquitous and can be found in underground, residential walls, laboratories, commercial and industrial structures. Pipeline fluids, including water, natural gas, waste and air. There are three manufacturing methods for manufacturing steel pipes. Production of seamless steel tubes using extrusion dies. Welded steel pipes are produced by winding steel sheets into tubes and welding joints. The seamless steel tube manufacturing process begins with a solid round billet. The billet is then heated to a high temperature and stretched and stretched until it becomes the shape of a hollow tube. As other steel pipe suppliers tell you, there are three major advantages to manufacturing pipes in this way. 　　The biggest advantage of seamless steel tubes is the increased ability to...

　　Submerged arc welding is an arc welding under flux layer combustion method. Welding arc between the wire and the weldment burning heat of the arc and arc welding wire ends near the base metal and solder melts, continue feeding the wire, and proceeds along a certain trajectory, an arc weld pool solidified metal is removed to weld the molten solder is solidified into a shell covering the surface of the weld slag, slag of molten pool and weld metal for protection against arcing and the pool by the outside air intrusion. 　　Submerged arc welding arc, wire, wire and shift interrupter such action is usually done by machine, it is known as submerged arc welding. SAW has the following advantages: ① high degree of mechanization, for welders require low skill levels; ② welding current, can be reduced weldments groove, high welding efficiency; ③ can be separated from molten solder metal contact with the air, the protective effect good, high weld quality; ④ covered with arc radiation, better wo...

　　Pipe hangers can be divided into three categories: load-bearing hanger, hangers and vibration-limiting bracket spiral welded pipe selection principles are as follows: 　　1. In the selection of spiral welded pipe hangers, should be borne in accordance with anchor size and direction of the load, displacement of the pipe, whether working temperature for cold type, pipe material and other conditions appropriate choice of hanger: 　　2. Design spiral pipe hangers, the card should be used wherever possible standard pipe, pipe supports and pipe hanging; 　　3. The welded pipe bracket, clamp-type pipe hanging over tube holder, steel tube hanging province, and making simple, the construction side cases, therefore, except in the following circumstances, should be adopted in welded pipe and tube inserted hanging; 　　1) tube medium temperature equal to or greater than 400 degrees carbon steel pipe material; 2) low temperature piping; 3) alloy steel pipe; 4) production pipeline maintenance req...

　　 1. Before molding work 　　Raw materials that strip, wire, flux. We must go through rigorous physical and chemical testing before it is put. Strip head and tail docking, single or double wire submerged arc welding, in rolled steel by automatic submerged arc welding. 　 　2. The molding process 　　Electric contact pressure gauge to control both sides of the conveyor pressure cylinder pressure to ensure the smooth delivery of the strip, the host is centrally located, so you should always check to adjust the vertical roll (especially around the head), to ensure delivery of the strip edges strict according to the process specified route runs through the meshing point design. By external or internal control roll forming, checking the perimeter, pipe ovality, straightness and other compliance standards, do not meet the requirements, will have to continue to make adjustments until the desired date. 　　 3. The welding process 　　The weld gap control device to ensure the weld gap to meet ...

　　Large diameter lsaw steel pipe hydrostatic testing machine during the pressure test, the first sealing means by the end of the test straight seam steel pipe sealed at both ends and low-pressure water injection in the exhaust pipe filling process air through the exhaust valve, in after the water is full of low-pressure, high-pressure water injection device through the booster is to pressurize the inner tube until the required test pressure. After reaching a predetermined test pressure predetermined dwell time, if the straight seam steel pipe leak, deformation phenomena in the pressure test is carried out relief. Then open the end seals, low-pressure water discharge, straight seam steel pipe to be tested to check for visual inspection station for suspicious penetration. According to the standard pressure for pressure testing process curve automatic recording device for recording. 　　Pressure steps: 　　1. The hydrostatic pressure test pressure Longitudinal working pressure and test p...

　　The heat treatment after welding is a new technique to eliminate residual stress. Preheating the material to the post-heat treatment temperature before welding and welding of the workpiece continued to keep the heating temperature, the use of insulation after the completion of the insulation of cotton to its slow cooling. This method can effectively reduce the welding residual stress and improve the stress corrosion resistance of metal. 　　After welding heat treatment can effectively reduce the welding residual stress, and the higher the heat treatment temperature, the better the residual stress elimination effect. The heat treatment of large diameter lsaw steel pipe can effectively improve the stress corrosion resistance of large diameter steel pipe. The higher the temperature of post-heat treatment, the more remarkable the stress corrosion resistance is. Diffusion method Metal carbide coating technology is the workpiece placed in special media, the proliferation of role in the wo...

　　 LSAW steel pipe quality check methods, during which the physical approach is the most commonly used inspection methods, physical examination is the use of physical phenomena to determine or check the method. 　　Magnetic force 　　Magnetic flaw detection can only find the appearance and appearance of magnetic straight seam welded pipe shortcomings, and the shortcomings can only do quantitative analysis, the nature and depth of the shortcomings can only be based on experience to estimate. Magnetic inspection is the use of magnetic field magnetization of ferromagnetic Longitudinal Welded Pipe leakage occurred to find the shortcomings. According to the measurement of magnetic flux leakage method is not the same, can be divided into magnetic powder method, magnetic induction method and magnetic recording method, during which the most widely used magnetic powder method. 　　Soaked inspection 　　Penetration test is the use of some of the liquid permeability and other physical properties...

　　With the continuous development and progress of the society, more and more industries are also developing rapidly. The steel pipe industry is one of them, but in the process of development of the steel pipe industry, there are more and more inferior steel pipe products. So, in the face of various seamless steel pipes and seamed steel pipes with uneven quality on the market, should we buy high-quality products? 　　When buying a lsaw steel pipe, we must first see the appearance of the straight seam steel pipe. Then we can distinguish the quality of the straight seam steel pipe. The surface of the high quality straight seam steel pipe is very smooth and delicate. The inferior straight seam steel pipe is very rough and the roughness is very heavy. Secondly, we can distinguish the quality by the size of the straight seam steel pipe. The quality of the straight seam steel pipe is in accordance with the standard, the inferior straight seam steel pipe There is no shortage of cut corners. Wh...

　　Submerged arc welding pipe welding, welding wire and steel pipes were connected to a power of two, the welding power source is AC or DC to DC, steel pipe connected to the negative terminal of the power supply, wire connected to the positive power supply wire through the little conductivemouth by the wire feeder to the workpiece to a certain speed transmission, arc burning between the wire and the workpiece. Arc stable burning is determined by wire to give speed and wire melting rate, when the same speed on the stability of arc burning. The arc voltage sent to the control wire speed often uniform to give and to give two kinds of ways. And static characteristic curve of the external characteristic curve and arc welding power source. Welding pipe welding with power density (welding current A / wire cross-sectional area mm2) a large, generally more than 50 A / mm2 characteristics, so the wire isokinetic gave to maintain the arc stable combustion is possible, the external characteristic ...