steel tube

　　From manufacturing processes we can know that SAW (LSAW, SSAW) and ERW pipes are entirely different right from formation, welding etc. and hence, the performance of both the pipes differ in the following aspects: 　　1. The surface quality of ERW pipes are better when compared to SAW (LSAW, SSAW) pipes, as they are smooth and have a better finish. In most of the SAW pipes, it is mainly about the weld reinforcement internally and externally. 　　2. The residual stress ratio in ERW is lower than SAW pipes. As ERW pipe deformation happens more in ERW followed by a sizing of flat oval, it results in elliptical vertical changes and necking, thereby making the stress smaller. The displacement of ERW pipes was smaller when compared along the axial and transverse incisions for comparison with SAW pipes built using the same material and it was also easy to detect. 　　3. The defects found in ERW pipes are lesser than SAW pipes. As there is a solvent deposit in SAW pipes, it results in more de...

　　Welded steel pipe, also known as welded pipe, it is made of steel sheet or strip that experience crimp forming welding. The production technology of welded steel pipe is simple, with high production efficiency, various specifications, less equipment investment, but the general strength is lower than the seamless steel pipe. 　　Since the 1930s, with the rapid development of high quality strip steel rolling production and the progress of welding and inspection technology, the weld quality constantly improves. Welded steel pipe specifications increase day by day, and replace seamless steel pipe in more and more field. In terms of the form of welded steel pipe, it can be divided into the weld seam welded pipe and spiral welded pipe. 　　The billet that welded steel pipe adopted is steel plate or strip steel. Because of the different welding process, welded steel pipe is divided into furnace welded pipe, welded (erw) pipe and automatic arc welding pipe. Due to its different welding form,...

　　Generally speaking, hydraulic (pneumatic) part in planning the use of mechanical performance, data are assumed to be uniform, successive, isotropic, according to the analysis of this approach is safe and that the plan will sometimes spiral steel pipe unexpected trouble cracking attack. 　　Study found that the use of brittle cracking and also member of the relevant temperature. After discussions we found that when the temperature drops below a certain temperature, brittle materials will change the situation, the impact absorbed energy decreased, this representation is called cold crisp, high-strength metal resources guessed low stress brittle episodes cracking process, the data arrangement is far from uniform, isotropic. Arrangements have cracks, there will be inclusions, porosity and other drawbacks can be funded look into guessed microcracks. Therefore, even when the program based on the operating temperature of the member to choose a suitable cold brittle temperature change infor...

　　 SSAW steel pipe often there will be some quality problems in the production and use, affecting normal use in some aspects, the need for spiral welded pipe to identify the quality, according to a certain way and performance testing, can produce significant in actual use role, then how to identify counterfeit spiral welded pipe method: the appearance often pockmarked face phenomenon. Generally the whole proportionate amount would be better, mainly taking into account the cumulative error and probability theory this problem. Some of the above please add if inadequate, we welcome the discussion of knowledge about aspects of the steel pipe together, advances constantly exchange. Pock is due to badly worn groove spiral welded pipe surface irregularities caused by uneven defects. Because of shoddy spiral welded pipe manufacturers have to pursue profits, rolling groove most often exceeded. The surface is easy to produce scarring. 　　Quality spiral welded pipe of uniform composition. High ...

　　 Spiral pipe factory should be done before the mechanical performance test and flattening test, and flaring test, and to achieve the standard requirements. Spiral steel pipe 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 addit...

　　 Seamless steel pipe   is a kind of long steel with hollow section and no joints. Smls pipe is used for conveying fluid pipe, structure with seamless steel tubes,  compared to the solid round steel, in the bending torsional strength phase at the same time, the weight is lighter, is a kind of economic cross section steel, widely used in the manufacturing of structural and mechanical parts, such as petroleum drill pipe, auto transmission shaft, bicycle frame and construction of steel scaffolding and so on. 　　Smls pipe made of high quality carbon steel or alloy steel, hot-rolled, cold-rolled (pull) of the points. 　　Usage 　　1. there are many types of Construction: pipeline transportation, floor covering, floor water heating, and hot water transportation. 　　2. processing, bearing sleeve, processing machine parts and so on. 　　3. electrical types: gas pipeline, water pipeline. 　　4. wind power plant antistatic tube. 　　There are many ways to produce smls pipe. According...

　　The steel billet is the product obtained by casting the molten steel produced by the steelmaking furnace. Steel billets from the manufacturing process can be divided into two types: die casting and continuous casting billet, the current casting process has been basically eliminated. 　　Continuous cast steel billet and rectangular billet mainly carbon steel , low carbon low silicon cold rolled material, high quality carbon structural steel, low alloy high strength steel, special steel as the representative. 　　Steel billet production process is following: 　　First, through the steel casting system of continuous casting equipment, directly from the molten steel into steel billet; 　　Second, the steelmaking system for the production of steel ingots or continuous casting slits through the rolling system of steel processing equipment out of semi-finished products; 　　Third, the steel production system of steel ingots through the forging equipment processing semi-finished products.

　　Hot forging means forging blank metal above the recrystallization temperature carried out. 　　Features: reducing the deformation resistance of metals, thus reducing bad forging force needed to deform the material, so that greatly reduced the tonnage forging equipment; altering the structure of ingots cast in forging process after recrystallization becomes coarse cast structure the new organization of small grains, and reduce defects in the cast structure to improve the mechanical properties of steel; improvingthe ductility is difficult for some of the more brittle at low temperatures in high alloy steel forging, which is important. Applicable large deformation resistance at room temperature, a poor metal plastic material. 　　Hot metal forging temperature range refers to the temperature and the temperature began to forge some interval between the end of the forging temperature, in order to prevent overheating, burning need to correctly determine the initial forging temperature and t...

　　The casing is mainly used to support the wellbore during and after drilling to ensure the normal operation of the entire oil well after the drilling process is completed. Different types of casing used in oil production: The surface oil casing is used to protect the well from contamination by shallow water and shallow gas layers and to support the wellhead equipment and maintain the other layers of the casing. Technical casing is used to separate the pressures at different levels so that the drilling fluid can be circulated and the production casing can be protected. 　　In order to install anti-blasting devices, leak-proof devices and tail pipes in wells. Oil reservoir casing drains oil and natural gas from the reservoir beneath the surface and is used to protect the well and stratify the drilling mud. When the oil casing is produced, the outer diameter is usually 114.3 mm to 508 mm. Domestic casing according to SY/T 6194-96 regulations, casing length is not fixed, its range of 8-13...

　　ERW carbon steel pipe welding advantages: 　　The resistance welding of ERW carbon steel pipe is a way of connecting the workpiece by welding between two electrodes, and applying the current, the application of the current through the thermal resistance produced by the surface of the workpiece and adjacent areas to heat it into the form of molten or plastic, so that the metal is connected. 　　Advantages of ERW carbon steel tube 　　1, the heating time is short and the heat concentration is concentrated, so the heating area is small, the deformation and stress are small, and the mortals do not have to adjust after welding and heat treatment. 　　2, gold bullion has been surrounded by plastic rings, and molten metal and air are blocked. Metallurgical process is simple. 　　3, there is no need to solder wire, electrode and other filler metals, and oxygen, acetylene, hydrogen and other welding materials, welding costs are low. 　　4, resistance welding has high output, no noise and harm...

    Stress corrosion of welded steel pipe can only occur under certain circumstances. It also has the following characteristics:     (1) Stress corrosion cracking can only occur when stress (especially tensile stress) is present. This stress can be applied stress, or the residual stress introduced during the welding and adding T process, or it can be the expansion stress caused by the wedge effect of the corrosion product.     (2) Stress corrosion cracking is a time-dependent lag failure, which is completely similar to hydrogen hysteresis cracking.     (3) Stress corrosion cracking is a kind of low stress brittle fracture.     Stress corrosion cracking is a common cause of failure of petrochemical equipment, especially welded steel pipes used in petroleum pipelines. Due to the unpredictability of stress corrosion cracking, it is the biggest hidden danger in the petrochemical industry. The necessary condition for stress corrosion ...

    Estate has boomed for several consecutive years nowadays. With its blossom, lots of industries have entered good momentum in selling. Steel pipe wholesale, from seamless steel pipe, to ERW steel pipe and so on, has thrived nowadays.     The main factor driving the steel pipe’s market growth is the market requirement. No matter you are in road engineering project, deep sea project, water supply project, or oil and gas transmission. We cannot ignore the role of steel pipe in these projects. Under this situation, steel pipe plays an important role in our daily life.     What’s more, high quality and practical usage would boost the huge market of steel pipes. With different standards, we can apply them in various areas which makes them a huge range of use.     http://www.tjxysteel.com/news/important-factors-driving-the-growth-of-steel-pipe-260.html

    ① Artificial visual inspection: lighting conditions, standards, experience, logos, pipe rotation.     ② NDT inspection.     a. ultrasonic testing UT     More sensitive to a variety of materials uniform surface cracks and internal defects in materials.     b. electromagnetic induction eddy current testing ET     Mainly point (hole shape) defect sensitive.     c. Magnetic MT and magnetic flux leakage inspection     Magnetic detection for detecting surface and near surface defects in ferromagnetic material.     d. electromagnetic ultrasonic testing     Does not require a coupling medium, it can be applied to high temperature and high speed, rough dry pipe surface inspection.     e. penetrant inspection     A fluorescent, colored, testing of steel surface defects.     Check www.tjxysteel.com for more info

    In the production of ERW steel pipe process will encounter many problems, the following will mainly talk about some of the issues given diameter machine analysis. In contrast, the lowest rate fixed problems mill, and the process it is also relatively simple, common sizing mill's production somethin There are several types.     1, Sizing scratch scratches primary attack in the horizontal and vertical axis on both sides of the pipe cross-section, multi-formed from flat roll and vertical roll pass of marginal. Especially after pass marginal R rounded sharpened, the following questions are presented once may cause injuries.     2, Drill pipe doubt is rare, the chance of comparison usually thin-walled tube produced episodes, and this is because of poor primary rigid thin-walled tube, and because the wall is thinner simple roll bite. So assume the following questions will form a drill pipe in the production of the incidents.     3, The tubes ...