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In the oil and gas industry, drilling machinery, oil pipelines, pumps, valves, transport equipment, tanks, reactors, a large number of large-scale failures are due to corrosion caused by wear.  The net result is not only caused the pipes, tanks, drill pipe, deep well pump damage and other facilities such as the leakage of crude oil in direct economic losses, but also cause fires, explosions and other catastrophic accidents, as well as environmental pollution, downtime and other serious consequence, greatly affected the safety and economic benefits.  Surface engineering technology can improve the surface properties of materials, such as wear resistance, corrosion resistance and high temperature performance. Surface works mainly by applying various surface coatings and coating techniques to form a mechanical, physical and chemical methods of surface modification. In the oil and gas industry, most of the equipment at high temperature, corrosion and other harsh environments, surface engineering is particularly important, including thermal spray technology, paint coating technology, electroless plating and laser surface treatment technology has been widely used in petroleum machinery, pipelines lanes and offshore oil equipment, not only can be used to repair parts, you can also extend the life and improve the overall performance, resulting in huge economic benefits.  Petroleum machinery mainly related to drilling, oil rigs used in engineering, fuel pumps, all kinds of casing tubing, sucker rods, drill bits and a variety of oilfield special car body parts. Most of these devices in harsh mining conditions in petroleum engineering field, many metal parts under load and accompanied by corrosion, wear, etc., causing them to fail prematurely damage occurred from shortened life shutdowns or replaced with new parts only increasing the material costs affect oil production, has brought about many losses.  In the oil pipeline, due to the external environment and internal multiphase media role in making internal and external pipelines are subject to different degrees of corrosion, resulting in serious consequences Endor. Pipeline failure for different forms and the environment, forming a complete system of pipeline corrosion. Currently the pipeline industry is the main application of surface engineering coatings coating process, while combining lining technology, mending techniques and insulation technologies.

Galvanized steel welding characteristics: Galvanized steel is generally in the low-carbon steel outer layer of zinc-plated, galvanized layer is generally in the 20um thick. Melting point of zinc in 419 °C, bp 908 °C or so. In welding, the zinc melted into the liquid floating on the surface or in the root of the weld pool position. Zinc has a greater degree of solid solution of iron, zinc, liquid etching along the grain boundary deep weld metal, low melting point of zinc to form a “liquid metal embrittlement.” Meanwhile, zinc and iron can form brittle intermetallic compound phase of the weld metal of these brittle plastic reduction in the tensile stress and cracks. If the welding fillet welds, especially T-joint fillet most prone to penetrate the cracks. When welding galvanized steel, bevel edge surface and a zinc layer under the action of the arc heat, oxidation, melting, evaporation and even volatile white smoke and steam, can easily cause weld porosity. Due to oxidation and the formation of ZnO, the high melting point of about 1800 °C or more, if the welding process parameter is too small, will cause slag ZnO, simultaneously. Since Zn as a deoxidizer. Produce FeO-MnO or FeO-MnO-SiO2 slag melting oxides. Second, because the evaporation of zinc, a large amount of white smoke evaporation, stimulate the human body, harmful effects, therefore, necessary to weld galvanized layer of polishing off.  Galvanized welding process control Galvanized steel welding preparation and the general low-carbon steel is the same, you need to pay attention is to seriously handle groove size and the nearby zinc coating. To weld penetration, beveling size should be appropriate, generally 60 ~ 65 °, to leave a certain gap, is generally 1.5 ~ 2.5mm; zinc in order to reduce the penetration of the weld, the weld before, the groove may be galvanized layer clear later welding. In actual supervision, using a centralized hit groove, leaving a blunt edge technology for centralized control, two welding process, reducing the possibility of lack of penetration. Welding galvanized steel pipe should be based on a matrix material selection, general ease of low carbon steel due consideration, the choice of J422 is more common.  Welding techniques: the first layer of multi-layer welding weld seam, try to make it melt the zinc layer vaporization, evaporation and escape the weld, which can greatly reduce the liquid zinc remain in the weld. In fillet welding, the same as in the first layer and make the molten zinc vaporization, evaporation and escape the weld, which is shifted forward end portion of the first electrode of about about 5 ~ 7mm, when the zinc layer melted and then continue to move back to its original position welding. Horizontal and vertical welding again, if use short-slag welding, such as J427, tend to be small undercut; roundtrip transportation if the front and rear of technology, but also can be non-defective weld quality.

Going to the stainless steel flange exhibition needs to make adequate preparations. In this small series also want to participate in some of their own feelings stainless steel flanges show to share with you. Here are a few of my feelings: First, the stainless steel flange participate in the exhibition mentality gracefully what you want, in the case that he did not do too, do not always think you can not, we should have confidence in ourselves. Second, to participate in the exhibition before the stainless steel flange Product information ready to be sufficient information to be familiar with. Because if their own stainless steel flange products are not familiar with it, even if you have great faith again, in vain, I found a customer asked the price of your product, ah, ah …… performance like when you have a answer It does not come up, people think? Third, to participate in the show to have a stainless steel flanges basic etiquette and manners. In fact, this, I think we ought to know everything, and nothing more than that is the way to treat people. So I would like to come back to participate in the stainless steel flanges, harvest is not only to bring money to benefit orders, there are more important harvest, that gain a lot of stainless steel flanges show friends, a lot of knowledge of wealth. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Stainless steel flange that because of different alloy content is pided into several hundred kinds of. How to discern between true and false of stainless steel flange is buyer? Except austenitic stainless steel flange magnet suck on the outside, ferritic and martensitic stainless steel flange have magnetic properties. Nickel element in reserves in the world are very few, the price is expensive. Therefore, the high content of nickel in stainless steel flange on the market price is higher also, and magnet is not on. In fact, there is a stainless steel flange is not on the magnet. That is less high manganese containing nickel or nickel stainless steel flange. This kind of stainless steel flange market prices higher than nickel stainless steel flange lower than 1000 yuan per ton. Some dealers are using people “good stainless steel flange on the magnet is not” misunderstanding, deceive consumers, as your price and the high nickel stainless steel flange. There are more than 100 stainless steel, features and functions. Generally makes decoration, landscape, sculpture, selection of austenitic stainless steel. Because of austenitic stainless steel for low heat conductivity, using it to do the kettle, frying pan, pot is not appropriate, will use a lot of energy, has also extended boiling water to cook. Do with ferritic stainless steel frying pan, pot, not only has excellent corrosion resistance, and its thermal conductivity is higher than austenitic stainless steel nearly half. In the washing machine barrel, water heater, xiancai basins, etc., as long as contact with water vessels should choose ferritic stainless steel. Someone complained about the stainless steel cutlery, this is because choose the wrong stainless steel. Austenitic stainless steel hardening, not suitable for cutting tool, cutting tool. Made of martensitic stainless steel cutting tools by heat treatment, such as change the hardness of stainless steel quenching and tempering. Iron and steel is how to distinguish between carbon content. Carbon content is under 2% of the iron carbon alloy steel, carbon content over 2% is called iron. Steel is because there are both toughness and elasticity and rigidity, are widely used. Life encounters is steel, but with different people call. For stainless steel flange, regardless of the magnets on it or not, as long as meet the quality standards, are all stainless steel flange. Therefore, from the perspective of metallurgy, there is no stainless iron. Corrosion resistant stainless steel flange are the main elements of chrome. Chromium content in more than 10.5% of the steel is not easy to rust. Smelting with different alloy elements, but also have the magnets and the distinction that are not on. Stainless steel is generally points according to the organization structure, can be pided into austenite, ferrite and martensite several categories. If into the molten steel in the different proportion of chrome nickel, etc., austenitic steel is tempered magnets are not on the stainless steel; If join into the molten steel chrome and small amounts of nickel and nickel (or without), tempered steel is magnets out of stainless steel, also called ferritic stainless steel; Martensite stainless steel flange of main alloying elements is chromium, iron and carbon. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Stainless steel pipe under normal circumstances is not easy to rust, but after exposure to chlorine and other harsh environments, or passivation layer surface is mechanically or chemically damaged, it is easy to rust than usual, so you see rusting stainless steel not surprising. Life is done with stainless steel passivation oxide, chromium oxide film thickness ratio of the surface of the fresh surface naturally formed film thickness, and are much more dense. All metal and atmospheric oxygen will be our perception of the reaction, the surface oxide film. Unfortunately, the iron oxide in the form of plain carbon steel proceed oxidation, corrosion continues to expand, eventually forming holes. You can use paint or oxidation-resistant metal (for example, zinc, nickel and chromium) plating to protect the steel surface, but, as people know, this protection is only a film. If the protective layer is damaged, the following steel began to rust Chromium is the corrosion resistance of stainless steel to obtain the basic elements, when the steel contains chromium content reaches about 12% chromium and corrosive media in the role of oxygen in the steel surface to form a layer thin oxide film (from the passive film), can prevent further corrosion of the steel substrate. In addition to chromium, the commonly used alloying elements nickel, molybdenum, titanium, niobium, copper, nitrogen, etc., in order to meet the various uses of stainless steel organization and performance requirements. Chemical composition Increases the corrosion resistance of stainless steel with the carbon content decreases, and therefore, most of the low carbon volume stainless steel, some steel wC even lower than 0.03% (e.g. 00Cr12). Stainless steel is the main alloying elements Cr, only when the Cr content reaches a certain value, only the corrosion resistance of steel. Therefore, stainless steel is generally wCr were more than 13%. Stainless steel further contains Ni, Ti, Mn, N, Nb and other elements. Species Stainless steel pipe is usually pided into: martensitic steels, ferritic steels, austenitic steel. In addition, the composition can be pided into: chromium stainless steel, stainless steel and chrome-nickel-chromium manganese nitrogen stainless steel. 1, ferritic stainless steel: chromium 12% to 30%. Its corrosion resistance, toughness and weldability with the increase of chromium content increased resistance to chloride stress corrosion better than other types of stainless steel. Fall into this category are Crl7, Cr17Mo2Ti, Cr25, Cr25Mo3Ti, Cr28 like. Ferritic stainless steel due to high chromium content, corrosion resistance and oxidation resistance are better, but the mechanical properties and process performance is poor, and more for large discontinuity as acid structure and antioxidant steel. Such steel resistant to corrosive atmosphere, nitric acid and saline solution, and has good high temperature oxidation resistance, thermal expansion coefficient, etc., for the nitric acid plant equipment and food, can also produce parts at high temperatures, such as gas turbine parts, etc. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Steel pipe surface treatment is a key factors to determine pipeline life, it is the ability to securely and steel pipe coating combined premise verified by research institutions, in addition to the life of the coating depends on the type of coating, coating quality and construction environment and other factors, steel pipe coating surface treatment on the life of about 50%, therefore, it should be strictly in accordance with the specification for the steel surface coating requirements, and continuously explore and summarize the continuous improvement of steel surface treatment method. Then the roughness on the coating produced a fundamental impact, that is, the size of adhesion, adhesion great use of time will naturally increase, life expectancy will increase, on the contrary, it will lead to the coating off easily reach the exposed steel antiseptic effect. Roughness is too small and would constitute an impact resistant coating adhesion strength decreases. Theoretical proof, the choice of which can get rid of almost all the rust grade oxide scale, rust and other contaminants, anchor pattern depth reached 40 ~ 100μm, Satisfied with the pipe coating adhesion begged, and spray (throwing) shot except rust process can lower operating costs and the rest from the mass arrival can * almost white level (Sa2.5) Skills condition. The use of a solvent, emulsion clean steel surface, in order to arrive remove oil, grease, dust, lubricants and similar organic matter, but it can not remove the steel surface rust, oxide, flux, etc., so as the anti-corrosion coating to help the wrist only. Typically, the diameter of Shot 0.8 ~ 1.3mm, grit particle size of 0.4 ~ 1.0mm, during which the major component is 0.5 ~ 1.0mm. For a metal anti-corrosion coating paint system performance reflected a suitable surface treatment is essential. Typically the metal surface will be accompanied by dust, grease, scale, rust layer, pollutants, salt or loose old paint. Oxide which is more common but the most easily overlooked part. High temperatures in the steel oxide generated during forging forming a dense oxide layer, usually attached to relatively strong, but more brittle than the steel itself, and the cathode itself, will accelerate the corrosion of metals. Anticorrosion pipe coating layer in addition to the life of the coating depends on type of coating quality and construction environment and other factors, the steel surface treatment on the coating life of about 50%, the coating solvent-free, no leaking substances, and thus will not contaminate the transmission medium, thus ensuring fluid purity and hygiene.

Straight seam welded pipe refers to the production of raw materials for steel in the weld seam welded straight on the device and parallel to the straight seam of the steel pipe. The main raw material is low carbon steel hot rolled coil, hot rolled, in petroleum, metallurgy, construction, mining, port, machinery and other industries widely used in oil and natural gas, low-pressure water gas transportation, mining fluid, conveyor roller, automotive transmission and so on.  Straight seam welded pipe production process is relatively simple, the main production process is high-frequency straight seam welded steel pipe and submerged arc welding straight seam steel pipe. Longitudinal is hot rolled coil through the molding machine, the deformation of the coil sleek cylindrical shape, the use of high frequency current skin effect and proximity effect or solder layer under the burning arc welding, the tube edge heating and melting, and the effect of the pressing force of a fused, the final cooling molding. Which uses high-frequency currents melting tube edge is called ERW (ERW), is called by arc melting LSAW pipe (LSAW).  Straight seam steel pipe is mainly used in water engineering, petrochemical industry, chemical industry, power industry, agricultural irrigation, urban construction. For the transport of liquids: water supply and drainage. For gas transportation: gas, steam, liquefied petroleum gas. For structural purposes: as piling pipe for bridges; docks, roads, buildings and other structures pipe.

Spiral pipe is a new, high-density polyethylene and modified carbon as the main raw material, and then through extrusion and rotational molding process technology to produce special pipe, which is CPVC, PVC pipes and cement pipes PVA ideal substitute with has high toughness, high strength, high insulation resistance, voltage resistance strong, light weight, long life and so on merit, and in the interior has a traction wire, to facilitate the introduction of cable and cable installation. For performance of spiral pipe, can be summarized as follows: With a spiral process characteristics, material saving light, suitable for transportation and construction. Tube Bending wider scope, can be bent, can avoid obstacles and therefore adapt to different terrain. Pipe shape using unsuccessful, thus enhancing the ring stiffness, effectively assume the external load, so the voltage capability is good. Spiral tensile strength, high tensile strength, and long tubes, buried after the overall performance is better, can withstand earthquakes and ground sinking. With good corrosion resistance, can be resistant to most chemical media, no electrochemical corrosion. Because of the characteristics of single-walled threaded pipe, the friction coefficient is small, the contact area is small, so that the traction is also greatly reduced. Wear rub wires, cables easy. The main raw materials used in a high-density polyethylene, so good insulation, to avoid eddy current transmission. With the safe operation of a wide temperature range of -30 ~ 90 ℃ in normal use. Therefore, a wide temperature range. Cables for floating spiral-shaped, surrounded by heat, cooling effect. Meanwhile, carbon spiral pipe with anti-ultraviolet radiation, anti-termite effect. The application range of the spiral pipe: mainly used for cable, communication cable, power cable protection, which can be used for cable crossing through the traffic to the cable across the river, bridge and other special conditions. Cable trench in the wet effect more prominent use.

304 stainless steel pipe is a more common type of stainless steel materials, many of the processing plant, 304 stainless steel pipe may occur in the process of machining line crack, scarring, surface defects such as inclusions, and scarring, these defects is roughly due to slab outer arc Angle of subcutaneous appeared transverse crack, there are tiny impurities mixed with in the crystallizer, finishing clean up without oxidation residue on the surface of the stainless steel pipe, as well as in the rolling process due to slab edges to the stainless steel pipe surface caused by the cartwheel. These defects not only lower the quality of the surface of the stainless steel pipe, also had an impact to the ascension of the quality of the product, so do a good job in prevention and treatment of 304 stainless steel pipe surface defects is very important. 304 stainless steel pipe billet surface deep scratches because the roll fan-shaped section of the local rotation, in order to prevent this happening, to timely maintenance in the fan section, it is strictly prohibited equipment over age. If the crystallizer with tiny impurities mixed with can cause the change of water quality, so to regularly check for water samples of mold. Reduce the weakening of stainless steel plate edge crack width to the extent and inhomogeneous deformation of wide plate rolling edge, reduce the amount of bandwidth when rolling steel plate is the best method, that is to say as far as possible with the wide end face slab width of steel plate production. Prevent 304 stainless steel pipe in the process of bending of the slab corner into the brittleness temperature zone, so for different width of face slab corner for dynamic temperature control, control and implementation of bending section with water area. Reduce the uneven deformation of rolled piece in will reduce the rolled piece on the difference of deformation resistance below, optimize the billet reheating process, reduce the slab surface temperature difference. Prevent the depth of the local burn mark and clear clean after finishing the secondary defects such as slab surface oxidation slag, through improve the slab sizing ability of 304 stainless steel pipe. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Hydrogen sulfide corrosion resistant pipeline steel mainly used to manufacture and transport sour gas pipeline. With the improvement of the delivery pressure and reduce the gas from the viewpoint of the cost of desulfurization, sometimes without desulfurization of the gas pipeline circumstances, so that such pipelines have to use the pipeline corrosion resistance to hydrogen sulfide. Hydrogen sulfide corrosion resistant steel for oil pipeline  and gas pipeline is the most difficult to produce a type of steel, because of its purity of molten steel, billet segregation controls and controlled rolling and cooling requirements of high traditional metallurgical processes can not meet the requirements . Usually in the acid gas environment, pipeline failure reasons are two: one is the sulfide stress corrosion cracking, referred to SSC. The defect is in the high strength steel surface and the internal stress and hydrogen sulfide corrosion under the action of the medium together with the stress direction perpendicular wall cracks. In the pipeline in service process, the high-grade steel pipeline prone to SSC. Another one is hydrogen induced cracking, referred to HIC. The cracks due to the high concentration of hydrogen sulfide gas environment into the steel corrosion inside the hydrogen produced in the vicinity of inclusions and segregation resulting enrichment of the surface parallel to the wall cracking. HIC occurs mainly in low-, medium-strength steel planted.

Stainless steel flange in industrial application are actually exist several or even dozens of elements at the same time, when several elements coexist in stainless steel flange this unity, their impact is much more complicated than single exists, because in this case not only to consider the elements themselves, and pay attention to the mutual influence between them, so the organization of the stainless steel flange is determined by the influence of various elements combined. 1, chromium in stainless steel flange Decided to stainless steel flange sex there is only one element of the genus, and this is the chromium, each kind of stainless steel flange contain a certain amount of chromium. To date, there has been no do not contain chromium stainless steel flange. Chromium is a stainless steel flange performance of the main elements of decision, the fundamental reason is that after adding chromium alloy elements into the steel, its internal contradiction movement to the aspects of development in the resistance to corrosion damage. 2, carbon duality in the stainless steel flange Carbon steel is used in industry, one of the main elements of the performance of the steel and organization to a large extent depends on the form of carbon content in steel and its distribution, the influence of the carbon is particularly significant in the stainless steel flange. Carbon in the stainless steel flange on the influence of the organization is mainly manifested in two aspects, on the one hand, carbon austenitic elements are stable, and the role of a large (about 30 times of nickel), on the other hand, due to the affinity of carbon and chromium is very large, complex carbide form – with chromium series. So, from both a strength and corrosion performance of candle, the role of carbon in stainless steel flange is contradictory. Understanding the influence of the rule, we can from the use of different requirements, choose different carbon content of stainless steel flange. In terms of the five steel grade because the carbon content, strength and corrosion resistance are also differentiated, cr13 0 ~ 2 crl3 steel has good corrosion resistance strength less than 3 crl3 and 4 cr13 steel, used in the manufacture of structural parts, after two steel grade due to high carbon and high strength can be obtained much used in the manufacture of spring, knives and other required high strength and abrasion resistance parts. And as 18-8 cr-ni in order to overcome the intergranular corrosion of the stainless steel flange, the carbon content of steel can be below 0.03%, or join a greater affinity than chromium and carbon element (titanium or niobium), make it not chromium carbide formation, such as high hardness and wear resistance becomes main requirements, we can increase the carbon content of steel properly increase the chromium content at the same time, both to meet the requirements of the hardness and wear resistance, and both – corrosion function, industry is used as the bearing, measuring tool and cutting tool has a stainless steel flange 9 cr18 and 9 cr17movco steel, carbon content is up to 0.85 ~ 0.95%, because of their chromium content is correspondingly improved, so still meet the requirements of the corrosion resistance. 3, the role of nickel in stainless steel flange after cooperate with chromium to play out Nickel is excellent corrosion resistant materials, as well as the importance of alloy steel alloying elements. Nickel is the formation of austenite in the steel element, but the low-carbon nickel steel to obtain pure austenitic organization, nickel content reaches 24%; And only make 27% nickel steel in some medium corrosion resistance change significantly. So the nickel can’t constitute stainless steel flange. But the nickel and chromium is present in the stainless steel flange at the same time, the nickel stainless steel flange has many valuable properties. 4, manganese and nitrogen can substitute for nickel chromium nickel stainless steel flange Cr-ni austenitic steel advantage although a lot of, but in recent decades because of nickel-base heat resistant alloy and nickel of less than 20% of the heat intensity development and application of steel, and the growing development of chemical industry of growing demand for stainless steel flange, and nickel deposits are less and concentrated distribution in minority areas, therefore appeared worldwide nickel in terms of supply and demand contradiction. In stainless steel flange and so many other alloys, such as large castings and forgings with steel, tool steel, refractory steel, etc.), especially the relative lack of resources of the country of nickel, nickel widely carried out section and other elements for scientific research and production practice of nickel in this aspect research and application more on manganese and nitrogen instead of nickel in the stainless steel flange and heat resistant steel. 5 add titanium, stainless steel flange or niobium is to prevent intergranular corrosion. 6, molybdenum and copper can improve the corrosion resistance of stainless steel flange. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Welded pipe has welded joints rigid, multi-layer welding, welding metal bulky, so welded joints in high-stress state, such as the weld metal has a higher yield point, it is difficult to relaxation through its plastic deformation of welded joints of high stress , then weld cracking in the heat affected zone is easy white zone or zones produce martensite formed HAZ cold cracking. Preventing cold cracking high-pressure pipe is welded most effective way to conduct additional documents overall 550 ~ 700 ℃ preheating, followed by use of heterogeneous weld welding material. Brittle fracture is caused by a variety of reasons. If precipitates on the grain boundaries, regardless of the intensity ratio of the matrix strength strong or weak, are all causes cracks; grain boundary segregation of inclusions also cause fracture; addition, even in far less than the yield limit of the alternating loads can also cause fatigue fracture phenomena. Generally, hydraulic (pneumatic) parts in the design using the mechanical properties are assumed material is uniform, continuous, isotropic, According to this method of design that is safe, sometimes accidents fracture accidents. It is shown that in the high-strength metal material that occur in low-stress of brittle fracture, the material is far from homogeneous tissue, isotropic. Tissues have cracks, there will be inclusions, porosity and other defects, which are a material can be seen in the micro-cracks. Further, brittle fracture is also the use of temperature and component. The study found that people when the temperature drops below a certain temperature, the material will be brittle transition state, the impact absorbed energy decreased, a phenomenon known as cold brittleness, so the design should be based on the operating temperature member Select a suitably cold brittle transition temperature of the material. Cold Drawn Seamless Steel Tube deformation is too small to reach the surface finish and dimensional accuracy requirements, but also unable to reach members of the strength index; deformation is too large, high-pressure pipe plasticity, toughness decreases too much, but the grain is pulled excessively elongate, forming a fibrous tissue, a significant anisotropy metals. Cold drawn seamless steel produced in the axial direction, parallel to the elongate direction of the grain, the intensity increased; pressure tube radially, perpendicular to the elongated direction of the grain, but lower strength, and maximum stress of the hydraulic cylinder is present in the radial direction of seamless, so much distortion on the performance of fully drawn tubes unfavorable. For steel and fibrous tissue appears dislocations, vacancies and other crystal defects are generally taken annealing or normalizing heat treatment methods to eliminate them. The purpose is to refine the grain annealing to remove tissue defects, reduce hardness, improved ductility.