Galvanized steel pipe is one kind of coating steel pipe.Galvanized square tube in two ways: hot-dipped galvanized square pipe and galvanized square tube into two categories. Galvanized square pipe with wet, dry, lead, zinc, oxidation reduction method. Different methods of hot dip galvanized steel pipe main difference in the acid leaching after cleaning, the method used to improve the surface activation of galvanized pipe quality. Are mainly the production of dry and oxidation-reduction method, which is characterized in Table. Electro-galvanized zinc layer of the surface is very smooth and dense, homogeneous; has good mechanical properties and corrosion resistance; hot dip galvanized zinc consumption lower than 60% to 75%. Galvanized of the technical complexity, but the single-sided coating, inside and outside surface of the coating thickness of the different double-sided coating, and thin-walled tube galvanized h ave to be using this method.
Pls contact Hunan great steel pipe co.,ltd if you would like to know more about coating carbon steel pipe
2016年10月31日星期一
DSAW Steel Pipe
DSAW pipe (Double Submerged Arc Welded) - When it comes DSAW steel pipe and tube distributors, you will find many companies will be able to buy and sell various wall thicknesses and grades. DSAW to some pipe buyers also stands for a “Straight Seam” pipe product, with the weld being visible on the outside as well as the inside.
Most DSAW pipe manufacturing companies and distributors carry in stock and have product available to them through mill contacts DSAW carbon steel pipe in sizes ranging from 18.00” O.D through to 60.00” O.D in New, Surplus, Mill Reject and Used Steel Pipe Products.
DSAW is available in different grades depending on your application, such as, many ASTM grades and API grades. Our lengths can range from cut to length in 2 ft pieces up to 60 ft lengths. There is the availability of longer lengths in some states but not all due to transportation. End conditions are beveled, straight cut or saw cut, and torch cut. Various paint and protective coatings are available such as, Fusion Bond Epoxy, Coal Tar Epoxy, Zinc, Organic and many more.
Much like other pipe manufactured processes, the manufacturing of Double Submerged Arc Welded Pipe involves first forming steel plates into cylindrical shapes. Then the edges of the rolled plate are formed so that V-shaped grooves are formed on the interior and exterior surfaces at the location of the seam. The pipe seam would then be welded by a single pass of an arc welder on the interior and exterior surfaces. The weldied arc is submerged under flux. What can be known as an advantage for this process is that welds would penetrate 100% of the pipe wall and produce a very strong bond of the pipe.
DSAW pipe is used in many applications such as Pipe Piling, Fabrication, Utility & Oil, Sign Poles, Offshore Drilling and Production, Road Casing, Road Boring, Culverts and many more construction uses.
All Steel Pipe offers you the opportunity to find a list of manufacturers and distributors to meet your DSAW pipe and tubing productneeds. Please Note: This information may not be 100% accurate, and is used for informational purposes only. Please consult your DSAW welded steel pipe supplier before starting your project.
2016年10月28日星期五
Classification of Welded Steel Pipe
Classification of welded steel pipe
According to weld shape, welded steel pipe can be divided into LSAW steel pipe and spiral welded pipe. Among them, the straight welded pipe: the production process is simple, high efficiency, low cost, rapid development. Spiral welded pipe: Longitudinal strength is generally higher than that, can narrow the billet production of large diameter pipe, you can also use the same width of the billet production of different pipe diameters. However, with the same length of straight pipe seam, compared weld length of 30 to 100%, and lower production rate. Therefore, most of the use of smaller diameter straight seam welding pipe, large diameter spiral welded pipe are mostly used.
According to weld shape, welded steel pipe can be divided into LSAW steel pipe and spiral welded pipe. Among them, the straight welded pipe: the production process is simple, high efficiency, low cost, rapid development. Spiral welded pipe: Longitudinal strength is generally higher than that, can narrow the billet production of large diameter pipe, you can also use the same width of the billet production of different pipe diameters. However, with the same length of straight pipe seam, compared weld length of 30 to 100%, and lower production rate. Therefore, most of the use of smaller diameter straight seam welding pipe, large diameter spiral welded pipe are mostly used.
By the application,welded steel pipe can be divided into general-use pipe, galvanized pipe, oxygen pipe, wire pipe, metric pipe, roller pipe, deep well pump tube, automotive tube, transformer tube, welding thin-walled tube , welding shaped tube and spiral welded steel pipe.
Single Radius Forming Process of Welded Steel Pipe
Single Radius Forming Process of welded steel pipe
This is a kind of common forming process, our country most small and medium-sized tube pass using the process of the unit. As shown in figure 4, each of groove for deformation are composed of a radius, from 6 ~ 7 horizontal roll forming process with the appropriate auxiliary deformation vertical roll in, some is flat vertical and white, some three flat roller is arranged in the last, the second three vertical roll, have distinguishing feature each, this technology has the advantage of roll processing is convenient, coarse forming part of the roll have certain common sex; Defect is inadequate deformation of steel strip edges, formed just after the end, into a welded pipe welding/peach shape 0, can guarantee welding quality of steel pipe. Steel strip after 2 ~ 3 layers forming the pass system, into the empty curved edge of the stage, as shown in figure 5, the curvature of edge is hard to change, even if again after a few mouths groove processing could not make edge to achieve the requirement of the squeezing roller. Although this forming process, the common rough shaping pass to a certain extent, but when changing the thickness of the steel tube, is not conducive to the edge shape. Coarse molding groove roller as consisting of a concentric circular arc, and the difference is steel pipe wall thickness, when changing the thickness of the steel tube is not concentric circles, thickness increases, the roller is raised, the middle section changes with different on both sides, on both sides of the roll gap increase is small, excessive pressure of edge, edge wave may be produced and affect the welding quality. When thinner welded pipe production, top roller pressure, on both sides of the roll gap reduction is also small, edge is not fully processed, have just end, also affect the welding quality. And rough forming roll the roller due to roll speed difference, slitting steel strip edge edge factors such as easy to wear and also can produce enough just side affect welding quality.
In the production of large diameter welded pipe, the thick forming roll diameter difference between middle and edge is big, roll the speed difference of the conference on steel pipe surface scratch, affect the quality of welded pipe's surface.
Factors Affecting the Quality of Welded Steel Pipe
Many factors affecting the quality of welded steel pipe, basically has the following several aspects:
(1) tube billet quality, chemical composition, mechanical properties, size deviation is the internal factors affecting the quality, appearance, etc.
(2) the welding process parameters: only by high frequency welding method, welding power, welding speed, temperature, the frequency of high frequency, extrusion pressure, impedance matching, the control of the triangle, etc all can affect the quality of welding.
The purpose of Pipeline Internal Coating
The purpose of Pipeline steel pipe internal coating are two
1:it is resistant to corrosion of oil and gas,
2 it is to improve the efficiency of the flow.
Because of the large steel pipe inner surface roughness, coating can decrease the flow resistance of medium to reduce power consumption, reduce transportation costs and can increase pressure pump station spacing, to save the engineering investment. Water pipe inside coating in addition to improving the efficiency of the flow, when the tap water, do not lower the quality of drinking water, not dissolved zinc impurities such as water pollution. General large diameter wall with mortar, small diameter tube plastic coated after galvanizing. Steel pipe pile pipe is not inside coating, coating outside to improve the corrosion resistance. Oil well pipe internal coating to increase resistance to oil, gas, corrosive, outside also to corrosion resistant coating. There are natural resin coated material, the type of solvent synthetic resin coating, synthetic resin, inorganic matter (cement slurry) and metals (zinc, aluminum plating, Galfan galvanized aluminum alloy), etc.Coating steel pipe is your choice.
1:it is resistant to corrosion of oil and gas,
2 it is to improve the efficiency of the flow.
Because of the large steel pipe inner surface roughness, coating can decrease the flow resistance of medium to reduce power consumption, reduce transportation costs and can increase pressure pump station spacing, to save the engineering investment. Water pipe inside coating in addition to improving the efficiency of the flow, when the tap water, do not lower the quality of drinking water, not dissolved zinc impurities such as water pollution. General large diameter wall with mortar, small diameter tube plastic coated after galvanizing. Steel pipe pile pipe is not inside coating, coating outside to improve the corrosion resistance. Oil well pipe internal coating to increase resistance to oil, gas, corrosive, outside also to corrosion resistant coating. There are natural resin coated material, the type of solvent synthetic resin coating, synthetic resin, inorganic matter (cement slurry) and metals (zinc, aluminum plating, Galfan galvanized aluminum alloy), etc.Coating steel pipe is your choice.
The Performance Requirements of Coating Steel Pipe
The performance requirements
Due to coating steel pipe production in the factory after going through delivery, transport, storage, and then laid in the soil or the bottom of the sea, so in addition to the corrosion protective performance, also requires a variety of physical strength.
(1) impact resistance, abrasion resistance, in order to prevent the coating from trauma caused by defect will focus from corrosion.
(2) pressure hardness. Coating film is being buried in soil, the soil pressure of compression, so the pressure hardness of paint film is very important.
(3) the insulation resistance. Resistance high can decrease the plating cost of corrosion.
(4) the cathodic disbonding resistance. If connect coating paint film defects will be centered on paint film defects of stripping phenomenon, which is referred to as a phenomenon of cathodic disbonding, its reason is due to low pipeline insulation resistance.
(5) viscosity. In various environment long time keep the viscosity of paint film.
The safety of the (6) in a different environment. In 70 ~ 80 ℃ or close to the high temperature of 100 ℃ to - 40 ~ 50 ℃ cryogenic wide temperature environment of the durability of the proposed requirements.
(7), tensile strength, elongation, resistance of paint film, at the scene of the laying of the welding parts repair, paint film itself damage is easy to repair.
The Purpose of Coating and Coating Steel Pipe
In order to prevent the corrosion and improve transportation efficiency and ensure drinking water quality, in recent years, the international steel pipe coating technology progress quickly. Steel pipe coating inside coating and two kinds of outer wall coating. According to the purpose and use environment choose coating material. Large diameter steel pipe coating material recommended wall with solvent (mainly) epoxy resin and synthetic resin mortar lining. The former is used for line pipe, water pipe, which is mainly used for water pipe. The outer wall coating is mainly asphalt coating, polyethylene coating, epoxy resin coating, etc. (for line pipe), and zinc rich paint or tar epoxide is used in the pipe pile. Recently in the sea to lay a pipe pile started using polyethylene coating steel pipe, this is because the PE coating on corrosion resistance and anti Marine biological adhesion performance is good, and can reduce the production cost.
Pipeline steel pipe internal coating are two: the purpose of it is resistant to corrosion of oil and gas, 2 it is to improve the efficiency of the flow. Because of the large steel pipe inner surface roughness, coating can decrease the flow resistance of medium to reduce power consumption, reduce transportation costs and can increase pressure pump station spacing, to save the engineering investment.
Water pipe inside coating in addition to improving the efficiency of the flow, when the tap water, do not lower the quality of drinking water, not dissolved zinc impurities such as water pollution. General large diameter wall with mortar, small diameter tube plastic coated after galvanizing.
Steel pipe pile pipe is not inside coating, coating outside to improve the corrosion resistance.
Oil well pipe internal coating to increase resistance to oil, gas, corrosive, outside also to corrosion resistant coating.
There are natural resin coated material, the type of solvent synthetic resin coating, synthetic resin, inorganic matter (cement slurry) and metals (zinc, aluminum plating, Galfan galvanized aluminum alloy), etc.
Hunan Great Steel Pipe Co.,ltd would like to supply many kinds of coating steel pipe with high quality.
2016年10月25日星期二
A comparison of various coating steel pipe production process
A comparison of various coating steel pipe production process,
process1: as the curtain coating method, coating sagging. And due to the unreasonable roller table and the chain design, coating exist more than two longitudinal and annular bruises. This process is to be eliminated. It is the only saving grace is the heating drying after coating. -
process 2: coating sag, perfect spiral scratches and the quality defects of the white. Especially severe is spiral raw coating thickness is only about one 5 of the specified thickness, and the look and feel is very poor. At the same time, the process of electrostatic spark a fire hazard, in recent years there have been several fire accidents, pose a threat to safety production. Without drying process is the process of important defects. Because of this process there are many difficult to overcome and restraining each other, the contradiction between the increasingly archaic, already can not adapt to the requirements of modern factory automatic coating, will gradually withdraw from steel pipe coating.
- process 3: is a kind of advanced technology, but not very mature technology. In between the two rollers between transient complete coating and curing, its advantages are obvious. But there are difficult to overcome weaknesses, such as: pretreatment on the surface of the steel tube is very strict, not taken, adhesion obviously decreased; UV coating and expensive equipment, high technology management requirements; Process of brittle coating, such as knock against, local fall off easily, and difficult to fill. Because there are so many problems that constrained in the promotion of the process. Four: - process is a kind of relatively advanced technology developed in recent years and the work of relatively mature art. It overcome other coating process is severely sag, bruises, efflorescence, fragile and other ills. Its produce coating adhesion, flexibility, rust prevention effect is good, very few sagging, beautiful and full. The process has simple operation, complete equipments, low technical management requirements and the characteristics of safety. Due to technical perfect called "steel pipe heating airless spraying technology".
We always do coating on the carbon steel pipe to protect.
Description ofanticorrosion coating steel pipe production line
Description ofanticorrosion coating steel pipe production line:
Outside the line pipe coating production line (range 219 ~ 1422 mm), line pipe coating production line (range 508 ~ 1422 mm), steel pipe coating capacity of 370000 t (ERW welded pipe, 70000 t, 300000 t) UOE welded pipe, line pipe internal and external coating area of about 5.2 million square meters/year.
Product specifications:
A coating line pipe (ERW welded steel pipe, UOE welded steel pipe)
S ERW welded steel pipe
S diameter: 219.1 ~ 610 mm s wall thickness: 4.0 ~ 19.1 mm s length: 8 ~ 18.3 m
S UOE welded steel pipe
S diameter: 508 ~ 1422 mm s wall thickness: 6.4 ~ 40 mm s length: 8 ~ 18.3 m
B in the coating line pipe (UOE welded steel pipe)
S diameter: 508 ~ 1422 mm s wall thickness: 6.4 ~ 40 mm s length: 8 ~ 18.3 m
Products:
S a: types of coated steel pipe, ERW welded steel pipe, UOE welded steel pipe
S b: coated steel pipe steel grade: A, b, X42 - X80
S c: types of coating: coating line pipe: three layer of polyethylene (PE), 5% 90% of three layers of polypropylene (pp) 3, 5% single fusion bonded epoxy (FBE) powder and double fusion bonded epoxy (FBE) powder. Internal coating line pipe: drag reduction, 80% and 20% anti-corrosion type.
Major equipment:
S a outer coating line pipe: steel tube feeding platform, steel pipe roller conveyer, steel tube surface engineering, transverse conveying test bench, the surface chemical cleaning device, induction heating device, shot blasting machine, shot blasting machine in cyclone and dust collecting device, purging device, roller coating line, dust removal system, PE/PP extrusion machine, extrusion machine adjustment platform, suction device, drying and coating area concentrated feeder system, water cooling section, the pipe cleaning, painting funnelled detection, etc.
S b internal coating steel pipe: steel tube feeding platform, outer coating funnelled test device, steel pipe roller conveyer, scarfing thermal device on the inner surface, within the shot blasting machine, shot blasting machine purging device in cyclone filter device, and within the rotating device, the spraying device, spray suction device, transverse conveying test bench, table dry room, curing oven, spray printing device, etc.
Carbon steel pipe
Carbon steel pipe or solid steel ingot is made of the capillary tube through the hole, then through the hot-rolled, cold rolled or cold call is made. Seamless carbon steel pipe in China's steel industry has an important position.
Seamless carbon steel pipe material is a round tube, pipe cutting machine embryos to go through cutting about 1 m of length blank, and sent by conveyor belt furnace heating. Billet is fed into the heating furnace, the temperature is about 1200 degrees Celsius. Fuel is hydrogen or acetylene. Furnace temperature control is the key issue. Round tube came out to punch through the machine through air pressure. Generally more common punch is tapered roll perforation machine, the punch high production efficiency, product quality, large diameter hole expansion, can wear a variety of steel. Perforation, round tube has been on three-roll cross rolling, rolling or extrusion. Squeezed off the tube after sizing. Sizing by high-speed rotary cone drill holes into the billet to form a tube. Pipe diameter by the sizing mill to determine the length of the drill diameter. After the pipe through the sizing into the cooling tower, cooling by water spray, steel after cooling, should be straightening. After the steel belt sent by straightening metal testing machine (or pressure test) for internal testing. If the pipe internal cracks, bubbles and other problems will be detected. After the pipe but also through strict quality control manual selection. Steel quality, the use of spray paint numbers, specifications, production lot number. By a crane into the warehouse.
If you would like to know more about seamless steel pipe and welded steel pipe（both are carbon steel pipe),pls contact hunan great steel pipe co.,ltd
Seamless carbon steel pipe material is a round tube, pipe cutting machine embryos to go through cutting about 1 m of length blank, and sent by conveyor belt furnace heating. Billet is fed into the heating furnace, the temperature is about 1200 degrees Celsius. Fuel is hydrogen or acetylene. Furnace temperature control is the key issue. Round tube came out to punch through the machine through air pressure. Generally more common punch is tapered roll perforation machine, the punch high production efficiency, product quality, large diameter hole expansion, can wear a variety of steel. Perforation, round tube has been on three-roll cross rolling, rolling or extrusion. Squeezed off the tube after sizing. Sizing by high-speed rotary cone drill holes into the billet to form a tube. Pipe diameter by the sizing mill to determine the length of the drill diameter. After the pipe through the sizing into the cooling tower, cooling by water spray, steel after cooling, should be straightening. After the steel belt sent by straightening metal testing machine (or pressure test) for internal testing. If the pipe internal cracks, bubbles and other problems will be detected. After the pipe but also through strict quality control manual selection. Steel quality, the use of spray paint numbers, specifications, production lot number. By a crane into the warehouse.
If you would like to know more about seamless steel pipe and welded steel pipe（both are carbon steel pipe),pls contact hunan great steel pipe co.,ltd
What is welded steel pipe
Welded steel pipe is one pipe the surface has the steel pipe joint,which is use the steel belt or steel plate material through the bending deformation into round ,square ect then welded into shape .
Welded steel pipe products are widely used in boilers, automobiles, ship building lightweight structural steel of the doors and windows, furniture, agricultural machinery, scaffolding, wire conduit, top shelves, containers, etc.. which can meet customer requirements, the special specifications welded pipe can be processed according to user requirements. Welded pipes for conveying water, sewage, gas, air, heating, steam and other low-pressure fluid and other uses.
According to different welding methods can be divided into electric arc welding tube, the high frequency or low frequency electric resistance welded pipe and gas welding tube, furnace welding pipe , bondi pipe, etc.
Electric Resistance Welded steel tube used in oil drilling and machinery manufacturing, etc.
Furnace tube welding pipe can be used for water gas pipe, etc .
LSAW steel pipe used for high pressure straight oil and gas transportation etc.
Spiral welded pipe used for the oil and gas transmission, and pipe pile etc.
Welded steel pipe dimensions:
Outer Diameter: 6mm-4064mm
Wall Thickness: 0.3mm-50mm
Length: 6mtr-18mtr
2016年10月24日星期一
Urban water supply with epoxy anti-corrosion coating steel pipe
Urban water supply with epoxy anti-corrosion coating steel pipe
Epoxy coal tar anti-corrosion paint (pole) and deep processing, the characteristics of epoxy coal tar anti-corrosion paint component and its role in the formulation: coal tar: guess and coal tar epoxy coal asphalt with goal is to guard against bituminous paint crack, to strengthen the resilience and adhesion when using coal tar heating stewing to repel water and impurities, heating temperature of 150 ℃ ~ 160 ℃. : epoxy resin is one of the important film-forming material, epoxy coal tar has a strong cohesive force, small contraction rate, good stability, high strength, good toughness, chemical good solid performance advantages. Coal tar, water proof, resistant to moisture, mildew, nitric oxide, carbon dioxide, chlorine, hydrochloric acid and other dilute acid, dilute alkali have certainly withstand the role. Asphalt containing aromatic compounds, the more it and epoxy wet the better solubility. Packing: also called extender pigment, increasing the film thickness, low capital and improve the coatings and film performance is used as packing material with talcum powder, zinc chrome yellow, mica, iron oxide red, etc. Cooked tung oil, make coating light resistance, alkali resistance, oil resistance, resistance to voltage, resistance to water. Internationally widely thought, coal tar epoxy paint is underground actinium layout the most ambitious anticorrosion coating, sea connotation construction in all kinds of key project is inseparable from the epoxy coal tar anti-corrosion paint. Coal tar epoxy paint anticorrosion strong level have s valued in the contemporary chemical set equipment deployment of epoxy resin market prospect.
Hunan Great Steel Pipe Co.,ltd could supply many kinds of coating of carbon steel pipe.
Epoxy coating steel pipe
The internal and external coating epoxy resin coating steel pipe is after many years of research, experiment, the latest development of a new type of tubing. Steel pipe for the base tube, using the modified epoxy resin powder on the internal and external wall coating of pipe. The plastic coated layer and steel strong bonding force, strong corrosion resistance, drag reduction, anticorrosive, compressive strength, the action such as antibacterial, good chemical stability and water resistance. It is generally not the restriction of the transmission medium, and no \"run, run, drip, crack\" the trouble back at home. It is widely used in municipal water supply, fire fighting, oil, gas, chemical industry, the pollution, mining, agricultural irrigation in the fields of fluid conveying, to replace high energy consumption, easy to rust, scale, life is short, heavy traditional tubing pipes, steel pipe, etc
Internal and external coating of epoxy resin composite pipe production process
Inside and outside the base carbon steel pipe coating epoxy resin first (galvanization steel tube) as the image preprocessing to grind the advantages: steel pipe automatic spraying uniform base material internal and external wall coating, good flowing property. CJ/T120-2008 standard and GB/T5135.20-2010 standard - will grind the good steel tube into the electric heating oven preheated, when the temperature reaches 230 ° ~ 250 ° (general preheating around one and a half hours) - the preheated pipe coating, coating, in the cases of solidifying (when the temperature reaches 200 degrees 15 minutes) - finished products. After spraying heating equipment preheat to 180 degrees to solidification of spray is good base material, advantage: when spraying epoxy resin powder is still not fully clinkering in base material of inside and outside wall, after 30 minutes of preheating curing, the curing agent of epoxy resin cured, makes the internal and external wall coating adhesion is stronger.
Construction of internal and external coating epoxy resin composite steel pipe surface pretreatment of the requirements of the quantitative indicators, the oil industry are relatively specific, such as:
Preheat tube before 1, shot blasting derusting, expelling dampness, preheating temperature of 40 ℃ ~ 60 ℃;
2, derusting should reach GB/T8923 rusting grade steel surface before painting and descaling grade Sa2.5 level, in the steel pipe surface anchor pattern depth of 40 microns to 100 microns.
3, mild steel pipe surface residual rust dust should be removed;
Be conducted within 4 h after 4, surface pretreatment coating;
...... And so on.
Once belong to take cover engineering, surface pretreatment coating coverage, whether the rust removal, it is hard to check whether clean thoroughly, and surface pretreatment is also costs money, so some enterprises to downplay the surface pretreatment, to save money, but in the end, the effect will be reflected in a product, pretreatment on the surface, the coating is solid, surface pretreatment of coating will fall off.
Our company supply carbon steel pipe with kinds of coating.
2016年10月21日星期五
Pickling Technics for Carbon steel pipe
Carbon steel pipe pickling method currently are used in the construction and management of two trough pickling pickling inner loop.
(1) trough pickling. The installed piping removed after decomposition into pickling bath soak treatment after passing their secondary installation. This method is suitable for larger diameter tube short, straight, easy to disassemble, piping and a small amount of on-site piping system hydraulics hydraulic piping construction of small amounts of occasions, such as pumping stations, valve stations inside, can be used trough pickling method.
(2) pipe loop pickling. In the installed hydraulic components in the hydraulic lines disconnected or removed with a hose, receivership, rinse cover joints, constitute rinse loop. Acid pump acid into the circulating loop pickling. The pickling method is more advanced construction technology in recent years, with the pickling speed, good effect, the process is simple, easy to operate, reducing pollution on the human body and the environment, reduce labor intensity and shorten the pipeline installation period, resolve long lines and complex piping pickling difficult problem, and to avoid secondary pollution problems trough pickling easy assembly occurs, has been widely used in the construction of large hydraulic system piping.
Pickling formula and process piping will cause unreasonable tube wall can not be completely ex oxide, wall over corrosion, corrosion coating steel pipe wall and the tube again residual chemical reactions sediment and other phenomena.
(1) trough pickling. The installed piping removed after decomposition into pickling bath soak treatment after passing their secondary installation. This method is suitable for larger diameter tube short, straight, easy to disassemble, piping and a small amount of on-site piping system hydraulics hydraulic piping construction of small amounts of occasions, such as pumping stations, valve stations inside, can be used trough pickling method.
(2) pipe loop pickling. In the installed hydraulic components in the hydraulic lines disconnected or removed with a hose, receivership, rinse cover joints, constitute rinse loop. Acid pump acid into the circulating loop pickling. The pickling method is more advanced construction technology in recent years, with the pickling speed, good effect, the process is simple, easy to operate, reducing pollution on the human body and the environment, reduce labor intensity and shorten the pipeline installation period, resolve long lines and complex piping pickling difficult problem, and to avoid secondary pollution problems trough pickling easy assembly occurs, has been widely used in the construction of large hydraulic system piping.
Pickling formula and process piping will cause unreasonable tube wall can not be completely ex oxide, wall over corrosion, corrosion coating steel pipe wall and the tube again residual chemical reactions sediment and other phenomena.
Processing performance of Carbon Steel
Processing performance
Most carbon steel smelting furnace use oxygen converter peace, high-quality carbon steel use electric arc furnace production also. Depending on the degree of deoxygenation steelmaking process, carbon steel can be divided killed steel rimmed steel and semi-killed steel ranged between. Affecting the performance of steel smelting method is mainly by the purity of the steel works. People by vacuum treatment, and blowing refining technology, higher purity are obtained steel, thereby significantly improving the quality of the carbon steel pipe. Plastic processing technology of carbon steel is usually hot and cold. After thermal processing, steel ingot in the small bubbles, osteoporosis and other defects are welded together to make steel dense tissue. Meanwhile, thermal processing can destroy cast structure, grain refinement. So wrought steel than cast has better mechanical properties. The cold steel, cold plastic deformation with increased strength and increased hardness, lower ductility and toughness. To improve the yield, widely used in continuous casting process of mild steel pipe.
Most carbon steel smelting furnace use oxygen converter peace, high-quality carbon steel use electric arc furnace production also. Depending on the degree of deoxygenation steelmaking process, carbon steel can be divided killed steel rimmed steel and semi-killed steel ranged between. Affecting the performance of steel smelting method is mainly by the purity of the steel works. People by vacuum treatment, and blowing refining technology, higher purity are obtained steel, thereby significantly improving the quality of the carbon steel pipe. Plastic processing technology of carbon steel is usually hot and cold. After thermal processing, steel ingot in the small bubbles, osteoporosis and other defects are welded together to make steel dense tissue. Meanwhile, thermal processing can destroy cast structure, grain refinement. So wrought steel than cast has better mechanical properties. The cold steel, cold plastic deformation with increased strength and increased hardness, lower ductility and toughness. To improve the yield, widely used in continuous casting process of mild steel pipe.
Chemical composition of Carbon Steel
Chemical composition
Chemical composition performance depends largely on carbon steel and carbon steel microstructure. In the annealed or hot-rolled state, with increasing carbon content of the steel increases strength and hardness, ductility and toughness and fall. Weldability and cold-formed deteriorated. Therefore, structural steel pipe, often limit the carbon content. Carbon steel elements and the residual impurity elements such as manganese, silicon, nickel, phosphorus, sulfur, oxygen, nitrogen, carbon steel also affects performance. Sometimes these effects reinforce each other, and sometimes against each other. For example: ① sulfur, oxygen, nitrogen can increase the hot brittleness of steel, and can reduce the amount of manganese or partially offset the thermal brittleness. ② residual elements manganese, nickel and outside to reduce the impact toughness of steel, an increase of cold brittleness. ③ lower intensity except sulfur and oxygen, the other impurity elements are to increase the strength of steel in different degrees. ④ almost all of impurity elements can reduce the ductility and weldability. Hydrogen in the steel can cause many serious defects, such as white spots, dots segregation, hydrogen embrittlement, cracks and other surface bubbling and weld heat-affected zone. To ensure the quality of steel, the steel must be reduced as much as possible the content of hydrogen (see stress corrosion cracking and hydrogen embrittlement). Deoxy into the residual elements such as aluminum, can reduce the aging tendency of low-carbon steel, grain refinement can also improve the steel toughness at low temperatures, but not too much margin. Residual elements in the charge brought in such as nickel, chromium, molybdenum, copper, etc., while high levels can improve the steel hardenability, but requires a high plasticity of special steel, such as deep drawing steel, it is unfavorable.
Hunan Great Steel Pipe Co.,ltd would like to introduce more knowledge of carbon steel pipe for you.
Chemical composition performance depends largely on carbon steel and carbon steel microstructure. In the annealed or hot-rolled state, with increasing carbon content of the steel increases strength and hardness, ductility and toughness and fall. Weldability and cold-formed deteriorated. Therefore, structural steel pipe, often limit the carbon content. Carbon steel elements and the residual impurity elements such as manganese, silicon, nickel, phosphorus, sulfur, oxygen, nitrogen, carbon steel also affects performance. Sometimes these effects reinforce each other, and sometimes against each other. For example: ① sulfur, oxygen, nitrogen can increase the hot brittleness of steel, and can reduce the amount of manganese or partially offset the thermal brittleness. ② residual elements manganese, nickel and outside to reduce the impact toughness of steel, an increase of cold brittleness. ③ lower intensity except sulfur and oxygen, the other impurity elements are to increase the strength of steel in different degrees. ④ almost all of impurity elements can reduce the ductility and weldability. Hydrogen in the steel can cause many serious defects, such as white spots, dots segregation, hydrogen embrittlement, cracks and other surface bubbling and weld heat-affected zone. To ensure the quality of steel, the steel must be reduced as much as possible the content of hydrogen (see stress corrosion cracking and hydrogen embrittlement). Deoxy into the residual elements such as aluminum, can reduce the aging tendency of low-carbon steel, grain refinement can also improve the steel toughness at low temperatures, but not too much margin. Residual elements in the charge brought in such as nickel, chromium, molybdenum, copper, etc., while high levels can improve the steel hardenability, but requires a high plasticity of special steel, such as deep drawing steel, it is unfavorable.
Hunan Great Steel Pipe Co.,ltd would like to introduce more knowledge of carbon steel pipe for you.
2016年10月20日星期四
Piling spiral weld steel pipe
Piling spiral welded steel pipe is hot rolled steel coil tube billet, often spiral shape, made of double-sided submerged arc welding or high frequency welding, used in civil construction, port, bridge pile foundation with steel pipe. Main reference standard of SY/T5040-2008 (with spiral weld steel pipe pile). Main specifications of pipe diameter range: diameter 325 mm to 2400 mm, wall thickness range from 8 to 60 mm length 6 to 12 m.
Introduction to the
Piling with spiral steel pipes in strip steel coil plate for raw materials, often warm extrusion molding, with automatic double wire welding double-sided submerged arc welding technology with spiral seam pipe.
(1) the raw material is steel strip coil, wire, flux. Have to pass strict physical and chemical inspection before investment.
(2) the strip head to tail docking, use single or double wire submerged arc welding, after rolled mild steel pipe adopts automatic submerged arc welding repair welding.
(3) before shaping, strip after flattening, cutting edge, edge planing, transmission and cleaning the surface to the flanging process.
(4) on both sides of the electric contact pressure gauge control conveyor under the pressure of oil cylinder pressure, ensure the smooth delivery of strip steel.
(5) the use of external control or internal control roll forming.
(6) the weld gap control device to ensure that meet the requirements of welding seam clearance, pipe diameter, and quantity of the wrong side of weld gap are tightly controlled.
(7) welding and welding are used within the United States Lincoln welding machine for single or double wire submerged arc welding, to obtain the stable welding quality.
(8) after welding the weld passes the online continuous ultrasonic automatic meter check, ensure the spiral weld nondestructive testing coverage of 100%. If there are defects, automatic alarm and spray tags, production workers to adjust process parameters, in a timely manner to eliminate defects.
(9) by air plasma cutting machine to cut the steel tube into single.
After cut into single pole (10), the head of every batch of steel pipe should be strictly check system, check the weld mechanical properties, chemical composition, amalgamation, steel tube surface quality and the nondestructive flaw detection, ensure that qualified pipe process, can be formally put into production.
(11) have continuous acoustic detection of weld mark parts, after manual ultrasonic and X-ray check, if there are defects, after repair, again through the nondestructive inspection, until defects have been eliminated.
(12) strip steel butt weld and fellowship with spiral weld d joint in the carbon steel pipe, all pass X-ray films and television inspection.
(13) each steel pipe after hydrostatic pressure test, radial sealing for the pressure. Test pressure and time are controlled strictly by steel pipe hydraulic microcomputer testing device. The parameters automatically printed out.
(14) pipe end machining, make the end verticality, slope Angle and the blunt edge to get accurate control.
This pipe is one kind of structural steel pipe.
The general difference between Cold drawn precision steel tube and ordinary seamless steel tube
The general difference between Cold drawn precision steel tube and ordinary seamless steel tube:
1, the main characteristics typically seamless steel pipe is a welding seam, can withstand greater pressure. Products can be very rough as-cast or cold dial.
2, cold drawn precision carbon steel pipe is the product appeared in recent years, mainly is the inner hole, the size of the outer wall with strict tolerance and roughness.
The characteristics of precision steel tube cold drawing (rolling) : 1. The smaller diameter. 2. High precision can be born small batch 3. Cold drawing (rolling) finished products of high precision, good surface quality. 4. The steel pipe transverse area is more complex. 5. Steel pipe is superior performance, compared to metal.
Seamless steel pipe and welded steel pipe is main product of Hunan great steel pipe co.,ltd.
Cold drawn precision seamless steel pipe
Cold drawn precision seamless steel pipe is used in the mechanical structure, the size of the hydraulic equipment of high precision and good surface finish of precision cold drawn seamless tube. Choose precision seamless pipe manufacturing mechanical structure or hydraulic equipment, etc., can greatly save the machining time, improve material utilization, at the same time to improve the quality of the product.
This is one kind of carbon steel pipe.
This is one kind of carbon steel pipe.
High quality carbon steel pipe
High quality carbon steel pipe, is a kind of carbon steel pipe, in addition to contain carbon (C) elements in steel and for DNA containing a certain amount of silicon (Si) (generally no more than 0.40%), manganese (Mn), high (generally no more than 0.80%, to 1.20%) alloy elements, excluding other alloying elements (except for residual element). This kind of steel to ensure that the chemical composition and mechanical properties at the same time. Its sulfur (S), phosphorus (P) content of impurity elements in general control under 0.035%.
Such steel production is bigger, USES broad, rolling (forging) more commonly made into round, square, flat profiles, such as plate and seamless steel tube. Mainly used in the manufacture of general structure and the mechanical structure parts, components and building structure and pipe conveying fluid. According to the requirement, sometimes need to heat treatment (normalizing or conditioning) after use.
We also call it "mild steel pipe".
Such steel production is bigger, USES broad, rolling (forging) more commonly made into round, square, flat profiles, such as plate and seamless steel tube. Mainly used in the manufacture of general structure and the mechanical structure parts, components and building structure and pipe conveying fluid. According to the requirement, sometimes need to heat treatment (normalizing or conditioning) after use.
We also call it "mild steel pipe".
2016年10月19日星期三
Hardness of carbon steel pipe
The hardness of carbon steel pipe commonly used Brinell, Rockwell, Vickers hardness of three kinds of indicators to measure.
In the steel standard, it is the most widely Brinell hardness, often expressed in the indentation hardness of the material in diameter, both intuitive and convenient. However, for a hard steel or steel thin NA.
Rockwell hardness
Rockwell hardness test tube with Brinell hardness test, as are the indentation test methods. The difference is that it is a measure of the indentation depth. Steel Rockwell hardness test is a very wide application, wherein after the Brinell hardness HB HRC use in steel standard. Rockwell applicable to the determination by the extremely soft to extremely hard metal materials, which make up not Brinell method, compared with Brinell method is simple and can be read directly from the dial hardness machine hardness value. However, because of its small indentation, the Brinell hardness values better method is accurate.
Vickers hardness
The mild steel pipe is also a Vickers hardness test indentation test method for the determination of a thin metal material and a surface layer hardness. It has a Brinell, Rockwell main advantages law, and to overcome their basic shortcomings, but not as convenient method Rockwell, Vickers method is rarely used in the steel standard.
Welded steel pipe
Welded steel pipe refers to welded steel strip or plate by means of bent round, square and other shapes and then welded into the surface of the steel pipe seam.
Welded steel blanks is used in steel sheet or strip, according to the different welding processes, it can be divided into the furnace pipe, welded (ERW) pipes and automatic arc welded pipe. Because of the different forms of welded pipe, which is divided into two and spiral welded pipe. Its shape is divided into round ends welded and shaped (square, flat, etc.) pipe.
Welded steel pipe, welded steel common market in general are: double submerged arc welded pipe(DSAW), high-frequency welded pipe (ERW), spiral submerged arc welded pipe(SSAW). Double submerged arc welded pipe is made using the molding machine has a tube opening, re-use double-sided submerged arc welding. Pipe is the use of high-frequency skin effect of high frequency current production of steel. The use of a narrow spiral submerged arc welded pipe is made of steel pipe-shaped roll, and use submerged arc welding, spiral weld, the weld compared Longitudinal length, compared with Longitudinal, it can use a specification made with a variety of large-diameter steel pipe.
If you would like to know more about welded steel pipe,pls visit:hunan great steel pipe co.,ltd
Welded steel blanks is used in steel sheet or strip, according to the different welding processes, it can be divided into the furnace pipe, welded (ERW) pipes and automatic arc welded pipe. Because of the different forms of welded pipe, which is divided into two and spiral welded pipe. Its shape is divided into round ends welded and shaped (square, flat, etc.) pipe.
Welded steel pipe, welded steel common market in general are: double submerged arc welded pipe(DSAW), high-frequency welded pipe (ERW), spiral submerged arc welded pipe(SSAW). Double submerged arc welded pipe is made using the molding machine has a tube opening, re-use double-sided submerged arc welding. Pipe is the use of high-frequency skin effect of high frequency current production of steel. The use of a narrow spiral submerged arc welded pipe is made of steel pipe-shaped roll, and use submerged arc welding, spiral weld, the weld compared Longitudinal length, compared with Longitudinal, it can use a specification made with a variety of large-diameter steel pipe.
If you would like to know more about welded steel pipe,pls visit:hunan great steel pipe co.,ltd
2016年10月18日星期二
ASTM A179 Steel Pipe
ASTM A179 low pressure boiler seamless steel tube production process is: the clarinet, alkaline cleaning, washing, pickling, rinse, leaching agent, drying, hot dip galvanized - - within the outer wind - air cooling, water cooling, passivation, water rinse, inspection, weighing, warehousing. Specific as follows: 1, plating pretreatment process
Alkaline cleaning, acid pickling, rinsing, 5 leaching agent, drying process.
1) part of steel tube surface is smeary, require alkaline cleaning.
2) use hydrochloric acid pickling to remove the oxide coating on the surface of the steel pipe.
3) is adhered on the surface of the steel tube to remove the residual acid and ferric salt, 2 times rinse should be carried out for steel pipe.
4) flux function from the steel surface to remove all the impurities, ensure steel tube in contact with the liquid zinc clean, good coating.
5) to prevent carbon steel pipe immersed in zinc pot blasting phenomenon occurs, for drying tube coated with solvent, drying temperature in 120-200 ℃, time of no less than 150 s.
2, hot dip galvanizing process
1) the temperature of molten zinc in zinc pot strict control in 450 + 5 ℃.
2) the drying processing of steel pipe chain by root removed by drying furnace, furnace roller, and then transported to the galvanizing furnace, rolling into the galvanized machine from three leaching zinc in a spiral.
3) three spiral phase is different, make the mild steel pipe on the spiral into a tilt state, with the screw rotation, steel tube side move down a slope Angle formation, and then into the liquid zinc, and continue to move down.
4) steel pipe automatic drop on the slippery course of zinc pot, the dial to the outside by ejecting agency, again by machine liquid zinc is put forward.
5) steel pipe up to the magnetic force grinding roller surface, absorb and move to drag out on the table.
3, post-treatment of plating process
Plating post-processing procedure including:, drag out, inside outside wind, water, inspection, passivation and print.
1) steel pipe through the outer ring, there is a row of holes on it, by compressed air, the steel tube excess liquid zinc away, bright and clean appearance.
2) under the satisfy the production rhythm, reduce the drag out speed, can control the amount of zinc, reduce the consumption of zinc.
3) blow can remove steel pipe inner surface excess liquid zinc, obtain the inner surface is bright and clean, be removed the zinc liquid zinc dust formation, be recycled.
4) water tank temperature control at 80 ℃, cooling water pump to the cooling tower for recycled after cooling.
5) water back out of the water tank, on 4 shelves, after the inspection will finish tube into the waste basket, the finished tube into the output table.
In 6) transport after passivation liquid spray ring finished pipe, the pipe surface passivation, after blowing outside ring, use compressed air to blow out redundant passivation solution.
7) delivery after laying in steam heating pipe line of drying stages, after dried, for printing packaging.
If you would like to know more about A179 steel pipe, pls visit:hunan great steel pipe co.,ltd
Kinds of Coating Steel Pipe
In order to protect the surface of steel pipe from moist and rust,to let the steel pipe keep the character still ,now many customer would like to purchase the steel pipe with coating.
The common coating is black coating, this is the cheapest,but the effect is not so satisfactory. so now many different better coating appeared as below:
3PE,FBE,Epoxy Coated,Powder Coating,Polyethylene Coating,Oil paing,Antirust varnish,Polymer concret pipes, Cement Mortar Lined Steel Pipe and Ceramic Lined Pipe.
If you would like to learn more about coating steel pipe and get quoation,pls contact:hunan great steel pipe co.,ltd
The common coating is black coating, this is the cheapest,but the effect is not so satisfactory. so now many different better coating appeared as below:
3PE,FBE,Epoxy Coated,Powder Coating,Polyethylene Coating,Oil paing,Antirust varnish,Polymer concret pipes, Cement Mortar Lined Steel Pipe and Ceramic Lined Pipe.
If you would like to learn more about coating steel pipe and get quoation,pls contact:hunan great steel pipe co.,ltd
Ceramic-lined Carbon Steel Pipe
Ceramic pipe with conventional steel, wear-resistant alloy steel pipe, cast stone and plastic pipe, steel pipe and other rubber has the essential difference. Ceramic pipe is steel outer and inner corundum. Corundum layer Vickers hardness 1100-1500 (Rockwell hardness of 90-98), the equivalent of tungsten-cobalt hard gold. High wear resistance than carbon steel pipe more than 20 times, it is much more superior than the usual bonding together corundum wheel performance. Now it is still a variety of corundum grinding wheel grinder cut hardened steel main wheel. Ceramic pipe corundum corundum wheel wear layer can be put away. Wear resistant ceramic pipe corundum layer may be formed mainly by a few millimeters thick, a Mohs hardness of 9, second only to diamond and silicon carbide, all oxides, which is the highest hardness. ¯ pipe and the component is only about 20% alumina, most of SiO2, SiO2 Mohs hardness of 7. Rare high chromium wear-resistant alloy tube or a Vickers hardness of about 400 (Rockwell hardness of about 50); lack of corundum hardness third. So wear-resistant alloy steel pipe, cast pipe wear both by composition and organization, but also by the thickness of the ceramic pipe abrasion resistance compared to them, has been a qualitative leap.
Ceramic-lined carbon steel pipe is the use of SHS - centrifugal method of manufacturing the ceramic pipe corundum melting point 2045 ℃, corundum layer and the steel layer structure due to process special reasons, the stress field is also special. Ceramic layer at room temperature compressive stress, steel layer subjected to tensile stress, the two opposites, into a balanced whole. Only the temperature rises above 400 ℃, since the thermal expansion coefficient between the two, the new stress field generated by the thermal expansion of the ceramic pipe and the stress field in the presence of the original offset each other, so that both the ceramic layer and the steel layer is free equilibrium. When the temperature rises to 900 ℃ to ceramic-lined steel pipe into the water Ling, repeated immersion times, the composite layer does not crack or crack, showing the common ceramic unparalleled thermal shock resistance. This performance would be useful in engineering construction, because of its outer layer of steel, coupled with the inner temperature is not cracked in the construction of the flanges, the purge port, explosion doors can be welded directly to the welding method can also be used connection, than wear and cast stone pipe, wear resistant steel pipe, rare earth abrasion steel, bi-metal composite pipe, steel pipe, steel rubber pipe in construction can not easily welded or soldered better. Ceramic-lined coating steel pipe good resistance to mechanical shock resistance, while during transportation, installation and beat two weight bracket bent, not broken off the composite layer.
Ceramic-lined carbon steel pipe is the use of SHS - centrifugal method of manufacturing the ceramic pipe corundum melting point 2045 ℃, corundum layer and the steel layer structure due to process special reasons, the stress field is also special. Ceramic layer at room temperature compressive stress, steel layer subjected to tensile stress, the two opposites, into a balanced whole. Only the temperature rises above 400 ℃, since the thermal expansion coefficient between the two, the new stress field generated by the thermal expansion of the ceramic pipe and the stress field in the presence of the original offset each other, so that both the ceramic layer and the steel layer is free equilibrium. When the temperature rises to 900 ℃ to ceramic-lined steel pipe into the water Ling, repeated immersion times, the composite layer does not crack or crack, showing the common ceramic unparalleled thermal shock resistance. This performance would be useful in engineering construction, because of its outer layer of steel, coupled with the inner temperature is not cracked in the construction of the flanges, the purge port, explosion doors can be welded directly to the welding method can also be used connection, than wear and cast stone pipe, wear resistant steel pipe, rare earth abrasion steel, bi-metal composite pipe, steel pipe, steel rubber pipe in construction can not easily welded or soldered better. Ceramic-lined coating steel pipe good resistance to mechanical shock resistance, while during transportation, installation and beat two weight bracket bent, not broken off the composite layer.
2016年10月17日星期一
Carbon steel pipe classification
Carbon steel pipe is a hollow steel bar, a large number of pipes for transporting fluids such as oil, natural gas, water, gas, steam, etc. In addition, engaged in bending, torsional strength, lighter, so it widely used in the manufacture of mechanical parts and engineering structures. Also used in producing a variety of conventional weapons, the barrel, shells and so on.
Carbon steel pipe classification: carbon steel pipe can be divided into seamless steel pipe and welded steel pipe points two categories. By the cross-sectional shape can be divided into the tube and shaped tubes, round steel is widely used, but there are some square, rectangular, semi-circular, hexagonal, equilateral triangle, octagon shaped steel tubing. For steel to withstand fluid pressure hydraulic test should be carried out to test its ability to withstand and quality, does not leak under pressure requirements, wet or expansion of qualified, some steel but also according to the requirements of the standard or demand side, curling trials, flaring test, flattening test.
Seamless steel pipe is ingot made of perforated or solid through the capillary tube, and then hot rolled, cold-rolled or cold call is made. Seamless steel pipe with a diameter* thickness specifications expressed in millimeters. Seamless steel pipe is divide into hot and cold seamless steel categories. Hot-rolled seamless steel pipes of general, low, medium pressure boiler pipe, high pressure boiler pipe, steel pipe, stainless steel pipe, oil cracking pipe, steel pipes and other steel and other geological. Cold-rolled subject to sub- general seamless steel pipe, low pressure boiler pipe, high pressure boiler pipe, steel pipe, stainless steel pipe, oil cracking pipe, the other steel, but also thin-walled carbon steel, alloy steel thin-walled, walled stainless steel, special steel pipe.
Welded steel pipe with plate or strip is bent after forming, then made by welding. Press the seam into the form of Longitudinal and spiral welded pipe. Divided into general -use pipe, galvanized pipe, blowing pipe, wire casing, metric pipe, roller pipe, deep well pump tube, automotive tube, structural steel pipe, welded tube, welding shaped tube and spiral welded pipe.
Carbon steel pipe classification: carbon steel pipe can be divided into seamless steel pipe and welded steel pipe points two categories. By the cross-sectional shape can be divided into the tube and shaped tubes, round steel is widely used, but there are some square, rectangular, semi-circular, hexagonal, equilateral triangle, octagon shaped steel tubing. For steel to withstand fluid pressure hydraulic test should be carried out to test its ability to withstand and quality, does not leak under pressure requirements, wet or expansion of qualified, some steel but also according to the requirements of the standard or demand side, curling trials, flaring test, flattening test.
Seamless steel pipe is ingot made of perforated or solid through the capillary tube, and then hot rolled, cold-rolled or cold call is made. Seamless steel pipe with a diameter* thickness specifications expressed in millimeters. Seamless steel pipe is divide into hot and cold seamless steel categories. Hot-rolled seamless steel pipes of general, low, medium pressure boiler pipe, high pressure boiler pipe, steel pipe, stainless steel pipe, oil cracking pipe, steel pipes and other steel and other geological. Cold-rolled subject to sub- general seamless steel pipe, low pressure boiler pipe, high pressure boiler pipe, steel pipe, stainless steel pipe, oil cracking pipe, the other steel, but also thin-walled carbon steel, alloy steel thin-walled, walled stainless steel, special steel pipe.
Welded steel pipe with plate or strip is bent after forming, then made by welding. Press the seam into the form of Longitudinal and spiral welded pipe. Divided into general -use pipe, galvanized pipe, blowing pipe, wire casing, metric pipe, roller pipe, deep well pump tube, automotive tube, structural steel pipe, welded tube, welding shaped tube and spiral welded pipe.
Low Carbon Mild steel pipe
Low carbon content of mild steel pipe is very low hardness and poor machinability, normalizing process may improve machinability. Mild steel pipe tends to have a greater timeliness, both quench aging tendencies, as well as a tendency to strain aging. When the rapid cooling from a hightemperature steel, ferritic scraping carbon, nitrogen saturation, it can also slow the formation of iron carbonitride was at room temperature, and thus the strength and hardness of steel, the lower the ductility and toughness, a phenomenon called quench aging. Even without quenching and low carbon air cooling will produce aging. Produce large amounts of low-carbon steel by deformation dislocations ferrite from carbon, nitrogen atom elastic dislocation interactions, carbon, nitrogen atom reign gathered around the wrong line. Such a combination of carbon and nitrogen atoms and the dislocation line is called the Coriolis-year-old air mass (Ke lop air mass). It will increase the strength and hardness of steel while reducing ductility and toughness, a phenomenon known as strain aging. Than quench aging of mild steel pipe during deformation plasticity and toughness greater dangers in the tensile curve has obvious upper and lower yield point. Since the yield on the yield point elongation occurs until the end, appear deformed due to uneven surface with folds formed on the surface of the sample, called Luders band. So many stampings are often scrapped. There are two methods of its prevention. A high pre-deformation method, the pre-deformed steel stamping place after a period of time will produce Luders band, so the pre-deformed steel stamping is placed before the time not too long. Another steel, aluminum or titanium is added to the formation of a stable compound with the nitrogen to prevent the formation of air masses caused by the Coriolis deformation of aging.
Carbon steel pipe is competitive in your purchasing structural steel pipe.
Carbon steel pipe is competitive in your purchasing structural steel pipe.
2016年10月16日星期日
Internal Coating steel Pipe
Using epoxy powder coating is for 30 years of history in a foreign country due to the wide range of sources of raw materials, production methods are simple, cheap, good performance, which do not pollute the environment and long service life, so far it is a good anti-corrosion coatings. Petroleum Institute of Construction Technology in China for the oil field pipeline corrosion problems and successfully develop the anti-corrosion coating of epoxy powder to fill the blank of the domestic pipeline anti-corrosion powder coating. the paint coating has excellent chemical resistance, good mechanical properties, high electrical insulation properties and good toughness. Corrosion tests predict coating life, the conditions intact Chu apply the paint to do the inner coating of oil, gas and water pipes, the life expectancy of up to l5 years; do sewage and mixed water injection pipeline within the coating, life up to 5 to 7 years. The construction method using the pipeline industry, the most widely used static thermal spraying method. According to the data reported, due to the transmission medium, the thickness of the coating of epoxy coating requirements are also different. Domestic oil, gas, water and sewage, etc. containing certain corrosive media, anti-corrosion pipe is the best thick coating. Electrostatic heat till coated thick coating, spraying a coating thickness of up to 250 ~ 350/an maximum thickness of up to 500, ~ 'n. Electrostatic Powder the moraine coated is a surface treatment of the solid powder, it has a simple, easy to operate equipment, process, free from the workpiece size limit.
Inner surface heat-resistant paints and coatings
The technology is the surface heat-resistant paint coating that mixed epoxy resin main agent and epoxy resin curing agent in the steel pipe (each about 5.5m), natural drying a certain period of time, more than 6O ℃ warm water or 60 ℃ or more hot air into the tube, forced drying, more than three hours to complete the steel pipe coating. The technology is mainly applied to water pipelines and transmission and hot water pipeinternal coated first surface treatment on the pipe wall, and then use the compressor by the pressure of air or nitrogen, Pressure between the resistance and the two applicator thermal coating in the pipe wall to form a uniform coating. Coating must 6O ° C more than warm water or 60 "C, hot air above the mandatory drying and natural drying is heat resistant to dissolution performance decreased significantly.
Internal coating steel pipe is different of outer coating,if you would like to learn more about it,pls contact us.
Inner surface heat-resistant paints and coatings
The technology is the surface heat-resistant paint coating that mixed epoxy resin main agent and epoxy resin curing agent in the steel pipe (each about 5.5m), natural drying a certain period of time, more than 6O ℃ warm water or 60 ℃ or more hot air into the tube, forced drying, more than three hours to complete the steel pipe coating. The technology is mainly applied to water pipelines and transmission and hot water pipeinternal coated first surface treatment on the pipe wall, and then use the compressor by the pressure of air or nitrogen, Pressure between the resistance and the two applicator thermal coating in the pipe wall to form a uniform coating. Coating must 6O ° C more than warm water or 60 "C, hot air above the mandatory drying and natural drying is heat resistant to dissolution performance decreased significantly.
Internal coating steel pipe is different of outer coating,if you would like to learn more about it,pls contact us.
Coating problem of ERW steel pipe
(1) Source of evaluation of external coating
Literature states: "steel surface condition is called environment that can coating and soil pipe insulation four weeks, four weeks the tube surface soil conditions are different and therefore the corrosion protection layer of the pipe is an important barrier to prevent soil erosion. " This is the basic starting point of the evaluation outer coating performance. Joe Leighton British company discussed from two different perspectives pipe coating system: European perspective is to make it able to withstand moisture, prevent corrosion, it is the "barrier" point of view. From this point of view it had a "PE" protective layer method. The North American point of view is to make it possible to oxidation resistance, chemical resistance and resistance to negative release properties to prevent corrosion, which is the "glue" point of view. From this point of view, resulting in a "FBE" law protective layer.
Another current trend is to the two foreign viewpoints known as "barrier" and "bond" combined, the development of a new point of view, the forthcoming European "PE" barrier protection layer method and North America "FBE" protection layer method to combine the development of an integrated-type "3PE" law protective layer. The new ideas, new technology, new methods in our country has begun to promote the application.
(2) the basic functions of the outer coating of steel
There are two aspects:
First, make the ERW steel pipe surface from electrochemical corrosion, bacterial corrosion protection of soil basic physical media,
Second, resist the soil medium move creep stress, basic mechanical protection method static stress and abrasion strength and structure and so on.
If you have other problem of coating steel pipe ,pls contact hunan great steel pipe co.,ltd.
Literature states: "steel surface condition is called environment that can coating and soil pipe insulation four weeks, four weeks the tube surface soil conditions are different and therefore the corrosion protection layer of the pipe is an important barrier to prevent soil erosion. " This is the basic starting point of the evaluation outer coating performance. Joe Leighton British company discussed from two different perspectives pipe coating system: European perspective is to make it able to withstand moisture, prevent corrosion, it is the "barrier" point of view. From this point of view it had a "PE" protective layer method. The North American point of view is to make it possible to oxidation resistance, chemical resistance and resistance to negative release properties to prevent corrosion, which is the "glue" point of view. From this point of view, resulting in a "FBE" law protective layer.
Another current trend is to the two foreign viewpoints known as "barrier" and "bond" combined, the development of a new point of view, the forthcoming European "PE" barrier protection layer method and North America "FBE" protection layer method to combine the development of an integrated-type "3PE" law protective layer. The new ideas, new technology, new methods in our country has begun to promote the application.
(2) the basic functions of the outer coating of steel
There are two aspects:
First, make the ERW steel pipe surface from electrochemical corrosion, bacterial corrosion protection of soil basic physical media,
Second, resist the soil medium move creep stress, basic mechanical protection method static stress and abrasion strength and structure and so on.
If you have other problem of coating steel pipe ,pls contact hunan great steel pipe co.,ltd.
2016年10月14日星期五
Expoxy coating
Epoxy resin coatings
Epoxy coating adhesion of metal, concrete, wood, glass and so on all have good adhesion; Alkali resistance, oil and water, good electrical insulation performance. But the aging resistance poor. Epoxy anti-corrosion coatings usually consists of two components epoxy resin and curing agent. The performance of the curing agent also affect the properties of paint film. Common curing agent are: (1) fatty amine and its modification. Characterized by room temperature curing, unmodified aliphatic amine bigger toxicity. (2) and their modified aromatic amine. Is characterized by slow, often under heat curing, the more toxic. (3) polyamide resin. Is characterized by good weatherability, less toxicity, good flexibility, corrosion resistance is a bit poor. (4) phenolic resin, urea formaldehyde resin and other resin. The resin and epoxy resin and got behind in membrane after high temperature baking paint film has outstanding corrosion resistance, and good mechanical properties and decorative.
Epoxy ester resin coating based on epoxy ester resin as film forming matter of a single component coating system. Epoxy ester resin composed of epoxy resin and vegetable oil fatty acid ester. The coating cost is lower, compared with common epoxy coating alkali resistance is poor. Commonly used for various metal outdoor equipment anticorrosion paint primer and chemical plant.
Epoxy coating steel pipe is one of our mainly coating steel pipe,welcome to send contact: hunan great steel pipe co.,ltd for more . .
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