ERW Steel Pipe

　　GB/T8162-1999 ( seamless steel pipe for structure). Mainly used for general structural and mechanical structures. Its representative material (brand): carbon steel 20, 45 steel; alloy steel Q345, 20Cr, 40Cr, 20CrMo, 30-35CrMo, 42CrMo and so on. 　　GB/T8163-1999 (seamless steel pipe for conveying fluid). Mainly used for conveying fluid pipelines on engineering and large equipment. The representative material (brand) is 20, Q345, etc. 　　GB3087-1999 (seamless steel pipe for low and medium pressure boilers). It is mainly used for pipes for conveying low and medium pressure fluids in industrial boilers and domestic boilers. The representative material is steel No. 10 and No. 20. 　　GB5310-1995 (seamless steel tubes for high pressure boilers). It is mainly used for high temperature and high pressure conveying fluid gathering boxes and pipelines on power stations and nuclear power plant boilers. Representative materials are 20G, 12Cr1MoVG, 15CrMoG, etc. 　　GB5312-1999 (carbon steel an...

　　 Galvanized steel pipes are generally coated with a layer of zinc outside the low carbon steel, and the galvanized layer is generally 20 um thick. Zinc has a melting point of 419 ° C and a boiling point of about 908 ° C. In welding, zinc melts into a liquid that floats on the surface of the bath or at the root of the weld. Zinc has a large solid solubility in iron, zinc liquid will deeply etch the weld metal along the grain boundary, and low melting point zinc forms "liquid metal embrittlement". At the same time, zinc and iron can form intermetallic brittle compounds. These brittle phases reduce the plasticity of the weld metal and cause cracks under tensile stress. If weld fillet welds, especially fillet welds of T-joints, are most susceptible to penetration cracks. When the galvanized steel is welded, the zinc layer on the surface and the edge of the groove is oxidized, melted and evaporated under the action of arc heat to volatilize white soot and steam, which easily ca...

　　The drill pipe connection thread is the weakest part of the drill string. In order to overcome this weakness, it is often necessary to thicken the end pipe wall of the drill pipe outward or inward to become an outer thickened or internally thickened drill pipe. The conventional drill pipe is made of alloy seamless steel pipe with different compositions. The existing alloy components are Mn, MnSi, MnB, MnMo, MnMoVB, etc., and the harmful components such as phosphorus and sulfur are not limited to more than 0.04%, according to GB3423-82. It is stipulated that the higher the steel grade of the drill pipe, the greater the yield strength. However, in the process of thickening, the drill pipe will cause thermal damage, so the thick drill pipe must be normalized, quenched and tempered at high temperature. 　　The active drill pipe (also called the upper drill pipe) is located at the uppermost part of the drill pipe column, and is clamped by the chuck of the drill vertical shaft or the power...

　　There are two classification methods for stainless steel pipe: one is classified into chromium stainless steel and chrome-nickel stainless steel according to the characteristics of alloying elements; the other is classified into M stainless steel, F stainless steel, and A stainless steel according to the state of steel in the normalized state. , A-F duplex stainless steel. 　　 1.ferritic stainless steel 　　The content of Cr in ferritic stainless steel is generally 13% to 30% and the carbon content is less than 0.25%. Sometimes other alloying elements are added. The metallographic structure is mainly ferrite, and there is no α<=> γ transformation during heating and cooling, and it cannot be strengthened by heat treatment. Strong anti-oxidation. At the same time, it also has good hot workability and certain cold workability. Ferritic stainless steel is mainly used to make components that require high corrosion resistance and low strength requirements. It is widely used in the m...

　　To control the welding quality of galvanized steel pipe , The factor of one person is the control focus. Therefore, before the welding, the skilled welder with the welder's certificate should be selected to carry out the necessary technical training. It is not allowed to be replaced at will, to ensure that the pipe welder is relatively stable. 　　Welder: The welder must ensure reliable performance and meet the needs of the process; the welder must have a qualified current and voltmeter to ensure the correct implementation of the welding process. The welding cable should not be too long, and the welding parameters should be adjusted when it is long. 　　Welding environment control: Ensure that the temperature, humidity and wind speed during welding are in accordance with the process requirements.

　　 Stainless steel pipe grade grouping 　　200 series - chromium-nickel-manganese austenitic stainless steel 　　300 series - chrome-nickel austenitic stainless steel 　　Model 301 - good ductility for molding products. It can also be hardened by mechanical processing. Good weldability. Wear resistance and fatigue strength are better than 304 stainless steel. 　　Model 302 - Corrosion resistance is the same as 304, because the carbon content is relatively high and the strength is better. 　　Model 303—It is easier to cut than 304 by adding a small amount of sulfur and phosphorus. 　　Model 304 - universal model; ie 18/8 stainless steel. The GB grade is 0Cr18Ni9. 　　Model 309 - has better temperature resistance than 304. 　　Model 316—After 304, the second most widely used steel grade is used primarily in the food industry and surgical equipment, adding molybdenum to give it a special structure that resists corrosion. It is also used as "ship steel" because it has better res...

　　In recent years, the offshore deep-water wharf project has also been constructed on a large scale in the coastal areas of China. As a pile foundation for the main bearing capacity of deep-water wharfs, spiral-welded large-diameter steel pipe piles are commonly used. In addition, repairing bridges, road repairs, high-rise buildings, etc. Piling pipes are required. The diameter of the pile pipe is getting larger and larger, and the pile pipe has the largest diameter pile pipe which has been produced to 3620mm and is widely used in coastal areas, rivers and lakes. 　　Standard: ASTM A252 　　Outer diameter: 219-3620mm. 　　Wall thickness: 6-25mm. 　　Length: 8.0---12m 　　Appearance quality: 　　There shall be no defects such as cracks, arc breaks, craters and pores on the surface of the welded steel pipe. The welds with the above defects may be repaired and the defects may be repaired or repaired. Steel pipe is allowed to be welded on the steel pipe. The steel pipe is allowed to be jo...

　　The materials used for anti-corrosion processing of spiral steel pipes play a decisive role in the quality of anti-corrosion steel pipes. When anti-corrosion processing is carried out, the original materials must be strictly tested, and the anti-corrosion materials for different anti-corrosion processing requirements are different. 　　1. Epoxy coal tar pitch anticorrosion is mainly applied to asphalt anticorrosive paint and polypropylene non woven fabric. 　　2. The original materials used for 3PE anti-corrosion steel pipes are polyethylene and polypropylene. 　　3. Cold wrap belt refers to the adhesive tape used for anti-corrosion wrapping. The cold wrap tape generally includes polyethylene anti-corrosion tape, polypropylene reinforced fiber anti-corrosion tape, aluminum foil anti-UV anti-corrosion tape, polyethylene 660 (modified asphalt) tape. , double-sided adhesive anti-corrosion inner belt and epoxy coal asphalt anti-corrosion tape. The implementation standards are SY/T 0414-9...

　　Classified by Production Methods 　　1. Seamless Steel Pipe - hot rolled seamless steel pipe, cold rolled seamless steel pipe, cold drawn seamless steel pipe 　　2. Welded Steel Pipe - longitudinal welded pipe, spiral welded pipe, electric resistance welded pipe 　　Classified by Cross-sectional Shape 　　1. Simple section steel pipe - round carbon steel pipe, square carbon steel pipe, rectangular carbon steel pipe, oval carbon steel pipe ect. 　　2. Complex section steel pipe - hexagonal carbon steel pipe with unequal edge, five plum shaped carbon steel pipe, double convex carbon stee pipe, double concave carbon steel pipe ect. 　　Classified by Wall Thickness 　　1. Thin walled carbon steel pipe 　　2. Thick walled carbon steel pipe 　　Classified by the Application 　　Carbon steel pipe can be used for thermal equipment, machinery industrial pipe, oil line pipe, geological drilling steel pipe, container steel pipe, chemical industry steel pipe, and other special purpose steel pipe...

　　Do you know what the mechanical properties of spiral steel pipe are? Let me introduce it to you. 　　First, the tensile strength (σb): the maximum force (Fb) of the sample during the stretching process, divided by the original cross-sectional area (So) of the sample (σ), called Tensile strength (σb) in N/mm2 (MPa). It shows the maximum ability of metal materials to resist damage under tensile forces. Where: Fb--the maximum force to be taken when the sample is broken, N (Newton), So--the original cross-sectional area of the sample, mm2. 　　Second, the spiral steel pipe yield point (σs): metal material with a yielding phenomenon, the force of the sample does not increase (maintained constant) during the stretching process, the stress can continue to stretch, called the yield point. If the force attack declines, the upper and lower yield points should be distinguished. The unit of the yield point is N/mm2 (MPa). Upper yield point (σsu): The maximum stress before the initial drop of th...

　　There are three main reasons for the oxidation of stainless steel tube : 　　1, Production process reasons: This is one of the causes of oxidation of steel products. From the perspective of production process and product characteristics, forming a thin oxide film on the surface of the product is the basic process to avoid oxidation and steel products. Different from one of the main features of other steel products, but when the production process is insufficient or inadvertent, the oxygen film in the air directly undergoes redox reaction with some elements in the product, resulting in incomplete or discontinuous oxide film. The product exhibits oxidation. 　　2, the proportion of product ingredients: some manufacturers in order to reduce production costs, thereby reducing the proportion of some important elements such as chromium, nickel, and other content such as carbon, such as not strictly according to product model, product characteristics In order to produce the proportion of pr...

　　Spiral steel pipes are widely used in life, but few people know what the main types of spiral steel pipe production lines are. 　 　1. single chain cooling bed 　　Single-chain cold beds use climbing structures. The cooling bed consists of a forward transport chain and fixed rails and has a transmission system. The steel pipe is placed between the two grips of the forward transport chain, and the fixed rail bears the weight of the steel pipe body. The single-chain cold bed uses the thrust of the forward transport chain finger and the friction of the fixed guide rail to make the steel pipe rotate, and at the same time, relying on the self-weight and lifting angle of the steel pipe, the steel pipe always abuts on the finger of the forward transport chain. Realize the smooth rotation of the steel pipe. 　　 2. double chain cooling bed 　　The double-chain cold bed consists of a forward transport chain and a reverse transport chain. Each of the positive and negative chains has a transmis...

　　As we all know, often drop large iron and steel industry, the price is extremely unstable, so what is the cause of this phenomenon? Shinestar Steel Research Institute found through research, technology and the characteristics of the iron and steel industry, the cost structure resulted in the imbalance between supply and demand environment quantity adjustment special difficulties. 　　Specifically, the characteristics of modern steel production technology determines that the industry has a strong scale effect.This means that the iron and steel enterprises need to spend a huge amount of money to buy equipment and equipment to build production systems, resulting in a higher proportion of fixed capital amortization of depreciation in the total cost.Shinestar Steel Group attaches great importance to R & D investment, its R & D production of carbon steel pipe , welded steel pipe, line pipe, galvanized pipe and other excellent products, the market was highly recognized. 　　Under no...

　　Through research this year Q345B erw pipe industry downstream of more than 20 industries consumption, can be found, infrastructure construction and the automotive industry is the main incremental source of steel consumption this year, the real estate industry, the hot situation mainly from the sales rise, rather than the construction area and A significant increase in investment. Overall, as of October, the cumulative consumption of steel during the year and the same period last year. However, in December 2015, the domestic major research institutions for this year's Q345B erw pipe industry demand forecast is basically a slap, which is due to the data show that from January to November, fixed assets investment and steel demand growth is weak As expected. As a result, "to the stock of the road is still difficult and long" "economic restructuring period, the slow growth of investment" for the 2016 Q345B erw pipe industry's basic forecast. In view of this, t...

　　 ERW steel pipe outer coating of the basic functions,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 sterss and abrasion strength and structure and so on. 　　The basic principles of the outer coating selected city gas pipeline: 　　a,good insulation properties and mechaniacal properties; 　　b,good resistance to cathodic disbanding performance; 　　c,good resistance to water,gas permeability; 　　d,good chemical resistance properties of soaking and aging; 　　e,low tempercature and high temperature performance; 　　f,easy mending and mending; 　　g,the price is reasonable.