steel tube

　　First, the raw materials and production capacity difference 　　 ERW steel pipe material is hot-rolled coil, UOE steel pipe material is hot-rolled steel. Therefore, ERW steel pipe can achieve a continuous pipeline operations, high production efficiency, low production costs; and UOE steel pipe is used to process, it can not achieve a continuous pipeline operations, low productivity, high production costs. Restricted ERW steel pipe coil thickness, the maximum thickness can be produced for 25mm, to produce a maximum diameter of 660mm; the maximum thickness of the UOE steel pipe can be produced as 40mm, produces the largest diameter is only limited by the width of the sheet, the current can be produce the maximum diameter of 1422mm. 　　Second, the difference between welding 　　ERW pipe welding without additional wire; UOE steel pipes need to add the wire. 　　Third, the appearance difference 　　ERW steel inside and outside welds required to be removed, so the antiseptic beneficial; ...

　　Seamless steel pipe is one of the important products in OCTG products. It is widely used in the manufacture of structural parts and mechanical parts, such as oil drill pipe, automobile transmission shaft, bicycle frame and construction of steel scaffolding and so on. Comparing with the other steel pipe, seamless steel pipe has stronger anti-bending and torsional ability under the condition of the same cross section area. It is widely used in the national economy, and is entitled to the "industrial blood vessel". Therefore, the quality of seamless steel pipe has very demanding requirements. 　　Seamless steel pipe inspection generally include: inspection geometry, surface quality; test chemical composition, mechanical properties, process performance, high and low times of the organization; NDT inspection; some special performance inspection and weighing length measurement. Here we will introduce you non-destructive testing 　　Under the premise of not damaging the specimen, ...

　　The internal and external area of the pipe can both be corrosive because of different factors. The external pipeline corrosion can mainly due to the surroundings, such as acid soil, wet conditions and so on. Factors that lead to internal corrosion are the oxygen content, temperature, pressure and flow rate of the liquid carried in the pipelines. Due to the above reasons, the anti-corrosive pipeline coating can be put into two corresponding categories, the internal and external corrosion-resistant coating. 　　 Internal anti-corrosion coating 　　Oil and gas liquid carried by the pipelines contains various chemical solid particles, some of which dissolve in the fluid while some remain. Those chemical particles remaining in the fluid travel in the pipe at a high speed, therefore, the internal coating is supposed to withstand friction caused by the fast moving particles. Besides, the internal coating material is expected to have a low surface roughness, thus, increasing the flow efficie...

　　Requirements for API 5L X52 seamless tube in standard. 　　1. there are no cracks, wrinkles, wrinkles, spalling, crusts and scales on the inside and outside surfaces of the steel pipes. These defects should be completely eliminated. The grinding of surface defects should be smooth and smooth. The depth of clearance should not exceed the negative deviation of nominal wall thickness. The actual thickness of the defect removal zone should not be less than the minimum allowable wall thickness of the steel tube. The welding method should not be used. 　　2. the straight path of the inside and outside surface of the steel pipe must be grind. The depth of clearance should not exceed the negative deviation of nominal wall thickness. The actual thickness of the defect clearance area should not be less than the allowable minimum wall thickness of the steel pipe. 　　3. end shape: cut both ends of the steel pipe into right angles and remove burrs. 　　The welding interface is not allowed on the...

　　The forming methods of large diameter lsaw steel pipe include :UOE forming method, one row roll forming method (CFE), CE forming. For the vast majority of the final steps of the molding process is to conduct a post-weld tube expanding full-length, in order to improve the quality of welded steel pipe shape. Expanding become large-caliber Longitudinal production to ensure the quality of the finished tube an important process. 　　Expanding is a use of hydraulic or mechanical means from urging the steel pipe along the pipe wall bulged radially outward pressure molding process. Mechanical than hydraulic mode, the device is simple and more efficient, the world's most advanced large-caliber Longitudinal several enlarged diameter pipeline system processes are adopted, the process is as follows: Mechanical expanding the use of the split-side portion of the enlarged diameter of the segments radially expand, so the tube along the longitudinal direction in a stepwise manner to achieve the ...

　　 Spiral steel pipe into the steel unit, multi-channel roll rolling strip gradually rolled up, a gap is formed with an opening round tube, squeeze rollers reduction adjustment, the weld gap control at 1 ~ 3mm, and the weld ends flush. 　　1. If the gap is too large, resulting in reducing the proximity effect, eddy current lack of heat, weld crystal combined indirect adverse arising from lack of fusion or cracking. 　　2. The gap is too small, causing the proximity effect increases, excessive soldering heat, cause weld Burning; weld or extruded, rolled after the formation of the pit, affecting the quality of the weld surface. 　　After the two edges of the tube is heated to welding temperature in the extrusion of squeeze rollers form a common metal grain mutual penetration, crystallization, eventually forming a strong weld. If the pipe extrusion pressure is too small to form a common crystal number is small, the weld metal strength is reduced by the force will produce cracking; if the...

　　Spiral pipe stacked right help protect the quality of spiral steel pipe , spiral steel pipe prolong life, prevent deformation, erosion, so orderly stacking spiral steel pipe, but also conducive to late spiral pipe loading, inventory. Spiral Pipe buyers should also strictly in accordance with the requirements of spiral steel pipe pile. 　　1) Spiral pipe open dumps, following necessary pad with wood or stone, stack surface needs slightly tilted to facilitate drainage, and pay attention to the material placed flat to prevent the causing bending. 　　2) Spiral pipe principle requires stacking under palletizing firm to ensure the safety of the premise, to do according to species, palletizing specifications, different varieties of materials to palletizing respectively, to prevent muddy and mutual erosion, but also easy to install a library car. 　　3) Prohibit storage of steel aggressive action items in spiral steel pipe pile position around. 　　4) Spiral steel pipe pile bottom should be...

　　In the long-distance pipeline construction, pipe-line account for a large proportion, generally 35% to 40% of line pipe accounts for investment projects total investment. How to choose a reasonable price, excellent performance pipe is particularly important to a reasonable choice of pipe to save construction investment, easy construction and safe operation of the pipeline system has a very important influence. Gas Pipelines straight seam steel high-frequency electric resistance welded steel pipe , spiral submerged arc welded pipe, LSAW steel pipe. Limited frequency straight seam electric resistance welded steel pipe diameter range is generally limited to domestic steel Φ406.4 mm or less, the largest in Japan has reached a diameter Φ508mm. 　　For large diameter pipe in the form of a spiral SAW, LSAW two kinds. Spiral welded steel pipe because the pipe forming process and characteristics of many shortcomings, the proportion is gradually declining in the long-distance pipeline. In othe...

　　 Spiral pipe factory should be done before the mechanical performance test and flattening test, and flaring test, and to achieve the standard requirements. Straight seam steel quality inspection method is as follows: 　　1, From the face of it, that is visual inspection. Visual inspection of welded joints is a simple procedure but widely used test method is an important part of product testing, the main defects and deviations are found on the surface of the weld size. Usually by the naked eye, with the standard model, gauge and test tools such as a magnifying glass. If the weld surface defects, weld defects there may be internal. 　　2, Physical test methods: physical test method is to use some physical phenomena assay or test method. Or within the workpiece material defect inspection, and are generally used NDT methods. NDT ultrasonic flaw detection, radiation detection, penetration testing, magnetic testing and so on. 　　3, Pressure vessels strength test: pressure vessels, in add...

　　The low carbon steel pipe with ceramic is composed of ceramic and metal composite pipes. Ceramic tube combines high hardness, good chemical inertness and steel advantages. It has excellent wear resistance, corrosion resistance, heat resistance and thermal shock resistance. Power plant coal powder, ash, slag, tailings, backfilling, coal, concentrator, coke plant coke particles, the sintering plant material transport life is 15 times higher than the ordinary steel pipe resistance to mechanical impact performance, can also be used for liquid aluminum, corrosive medium transport. 　　The performance of ceramic low carbon steel pipe: 　　1, wear resistance: the ceramic content of the inner lining Al2O3 ceramic composite pipe is more than 90%, the microhardness is HV1000-1800, it has very high wear resistance, its wear resistance is more than ten times better than the quenched carbon steel, better than the tungsten carbide bit. 　　2, corrosion resistant ceramics is a neutral material, wit...

　　Corrosion in the form of seamless steel pipe for buried pipelines are divided into two kinds of localized corrosion and uniform corrosion, localized corrosion mostly dominated, the danger is also the largest. Pipe in the soil erosion process is mainly electrochemical dissolution process, due to the formation of a corrosion cell causing corrosion of the pipe perforation. Press corrosion cell anode and the cathode region of the size of the pitch, but also form a corrosion cell corrosion steel pipe into micro and macro cell corrosion two categories. The so-called micro-cell corrosion, refers to the role of a few millimeters from the pipeline micro-cell or even just a few microns apart anode and cathode consisting caused by corrosion. Its shape is very uniform characteristics, it is also called uniform corrosion. Since the micro-micro anode and cathode separated by very close, so the micro-cell corrosion rate does not depend on the resistivity of the soil, only slightly depends on the a...

　　Galvanized steel is just steel that has been galvanized on it's surfaces which coated with a zinc layer, providing a substantial amount of protection from corrosion. Steel pipes made from galvanized steel are able to resist corrosion, withstand harsh weather, and are stronger and lighter than many other pipes. There comes the question: Will the galvanized steel pipe rust? To understand the question, we should learn about the principle their manufacturing and rust protection. 　　Galvanized pipes can be divided into hot-dipping galvanized pipe and electro-dipped pipes according to the manufacturing methods. hot-dipped galvanizing is produced by dipping ordinary steel into a pool of molten zinc. But for electro-galvanizing, the steel is dipped into an electrolyte solution containing zinc and makes use of electrolysis to create the corrosion resistance coating. 　　Galvanizing is process of coating zinc over steel. Zinc coating normally melts at 850 to 900F & vaporizes at 1500F ...

　　How to distinguish the good from the bad of thick - walled seamless tube? There are six ways to do this: 　　1, high quality composition is uniform, the thick wall seamless tube cold shearing machine high tonnage, cutting head end face smooth and neat, and shoddy material because the material is poor, cutting head end face often have meat, or uneven, and no metallic luster. And because the manufacturer of fake and inferior materials products cut the head less, the head and tail will appear big ears. 　　2. The pseudo-thick-walled seamless tube has no metallic luster and is of a reddish color or similar color to pig iron, for two reasons, its billets are adobe. The temperature of the fake and inferior materials is not standard, and their steel temperature is measured visually, so they cannot be rolled in accordance with the specified austenite area, and the performance of the thick wall seamless pipe cannot reach the standard naturally. 　　3, and inferior thick-walled seamless tube c...

　 　Factory casing process: 　　Steel ingot heating, hydraulic piercing, reheating, elongation, periodic rolling, reheating, sizing, cooling, straightening, pipe cutting and inspection. 　　Ingot heating: 216 mm cycle tube mill and annular furnace, 318 mm cycle tube rolling mill original design and two circular furnaces. 　　Hydraulic punching: 216mm is 10kN hydraulic press, 18318mm punch press is made by 18kN hydraulic press. 　　Extension: the oil and casing factory is using two roller guide extensions. 　　Reheat: use tray furnace, use rolling mill cycle, then do not use heat to enter the furnace. 　　Selection: using a double - roll 5 - stand sizing machine. 　　Oil casing cold bed is a one-way chain cold bed. 216mm circulating rolling mill product specifications 114.3 to 319mm, wall thickness 6 to 40mm; 318mm circulating rolling unit rolling product specifications 168 to 377mm, wall thickness 6 to 40mm. As an oil well pipe, all kinds of casing and some drill pipes can be produced. ...

　　General welded pipe is used for transporting low pressure liquid. Use Q195A, Q215A, Q235A steel manufacturing. Also can be used to other mild steel welding manufacturing. Welded steel pipe for pressure, bending, flattening and so on experiment, the surface quality is a certain request, usually the delivery length is from 4 to 10 m, which often required scale delivery of the goods. Of the specifications of the welded steel pipe in nominal diameter nominal diameter is different from the actual, welded pipe with wall thickness by the regulation with ordinary steel pipe and thickening structural steel pipe, steel pipe and the form of the pipe end points with thread and don't take two. 　　Galvanized steel pipe, in order to improve the corrosion resistance of steel tube, for galvanized welded steel pipe commonly. Zinc galvanization steel tube hot dip galvanized and electrical steel, hot dip galvanized zinc coating thickness, the cost of electric is low. Oxygen tube welding is used for...