Search Results

304 stainless steel pipe is produced according to the United States ASTM standard stainless steel brand. 304 stainless steel pipe is equivalent to China’s 0Cr19Ni9 (0Cr18Ni9) stainless steel pipe. 304 stainless steel pipe classification there are many, the first is seamless pipe and straight seam welded steel pipe, the most basic classification is 304 stainless steel pipe and industrial fluid delivery with 304 stainless steel pipe. It is a versatile stainless steel pipe that is widely used to produce equipment and machines that require good overall performance (corrosion resistance and formability). For example: food production equipment, the former chemical equipment, nuclear energy and so on. Grade specifications for 304 grade stainless steel Grade UNS No Old British Euronorm Swedish SS Japanese JIS BS En No Name 304 S30400 304S31 58E 1.4301 X5CrNi18-10 2332 SUS 304 Typical Chemical Composition % (max values, unless noted) Weight % C Mn P S Si Cr Ni 304 .08 2.00 .045 .030 1.00 18.0-20.0 8.0-11.0 Typical Mechanical Properties Grade Tensile Ultimate/Min Yield/Min Elongation/Min KSI MPA KSI MPA % 304 75 515 30 205 35 Physical properties of 304 grade stainless steel in the annealed condition Grade Density (kg/m3) Elastic Modulus (GPa) Mean Coefficient of Thermal Expansion (μm/m/°C) Thermal Conductivity (W/m.K) Specific Heat 0-100°C (J/kg.K) Electrical Resistivity (nΩ.m) 0-100°C 0-315°C 0-538°C at 100°C at 500°C 304/L/H 8000 193 17.2 17.8 18.4 16.2 21.5 500 720 304 stainless steel pipe anti-intergranular corrosion performance is good, with excellent corrosion resistance and cold processing, stamping performance, can be used as a heat-resistant stainless steel. At the same time, the steel at -180 ℃under the conditions of its mechanical properties are still good. In the solid solution state of steel plasticity, toughness, cold workability in the oxidizing acid and atmospheric, water and other medium corrosion resistance, therefore, it is the most widely used steel. 304 stainless steel pipe tolerances: NPS Designator Permissible Variations in Outside Diameter​ Over In. Under In. 1/8 to 1-1/2, incl 1/64 (0.015) 1/32 (0.031) Over 1-1/2 to 4, incl 1/32 (0.031) 1/32 (0.031) Over 4 to 8, incl 1/16 (0.062) 1/32 (0.031) Over 8 to 18, incl 3/23 (0.093) 1/32 (0.031) ​ Minimum Wall Thickness on Inspection: tn * 0.875 = tm Where: tn = nominal wall thickness, in. [mm], and tm= minimum wall thicknesses, in. [mm] The wall thickness is inch-pound units is rounded to three decimal places in accordance with the rounding method of Practice E29. The wall thickness in SI units is rounded to one decimal place in accordance with the rounding method of Practice E29. · This table is a master table covering wall thicknesses available in the purchase of different classifications of pipe, but it is not meant to imply that all the walls listed herein are necessarily obtainable for the applicable product specification. Nominal Thickness Minimum Thickness on Inspection Nominal Thickness Minimum Thickness on Inspection Nominal Thickness Minimum Thickness on Inspection in. mm in mm in mm in mm in mm in mm 0.068 1.7 0.060 1.5 0.294 7.5 0.257 6.5 0.750 19.0 0.658 16.6 0.068 2.2 0.077 2.0 0.300 7.6 0.262 6.7 0.812 20.6 0.710 18.0 0.091 2.3 0.080 2.0 0.307 7.8 0.269 6.8 0.843 21.4 0.736 18.7 0.095 2.4 0.083 2.1 0.308 7.8 0.270 6.9 0.854 21.7 0.756 19.2 0.113 2.9 0.099 2.5 0.312 7.9 0.273 6.9 0.875 22.2 0.766 19.5 0.119 3.0 0.104 2.6 0.318 8.1 0.278 7.1 0.906 23.0 0.783 20.1 304 stainless steel pipe’s theory weight calculation formula: (diameter – wall thickness) × wall thickness × 0.02491 = weight per meter (kg) Corrosion Resistance Excellent in a wide range of atmospheric environments and many corrosive media. Subject to pitting and crevice corrosion in warm chloride environments, and to stress corrosion cracking above about 60°C. Considered resistant to potable water with up to about 200mg/L chlorides at ambient temperatures, reducing to about 150mg/L at 60°C. Heat Resistance Good oxidation resistance in intermittent service to 870°C and in continuous service to 925°C. Continuous use of 304 in the 425-860°C range is not recommended if subsequent aqueous corrosion resistance is important. Grade 304L is more resistant to carbide precipitation and can be heated into the above temperature range. Grade 304H has higher strength at elevated temperatures so is often used for structural and pressure-containing applications at temperatures above about 500°C and up to about 800°C. 304H will become sensitised in the temperature range of 425-860°C; this is not a problem for high temperature applications, but will result in reduced aqueous corrosion resistance. Heat Treatment Solution Treatment (Annealing) – Heat to 1010-1120°C and cool rapidly. These grades cannot be hardened by thermal treatment. Welding Excellent weldability by all standard fusion methods, both with and without filler metals. AS 1554.6 pre-qualifies welding of 304 with Grade 308 and 304L with 308L rods or electrodes (and with their high silicon equivalents). Heavy welded sections in Grade 304 may require post-weld annealing for maximum corrosion resistance. This is not required for Grade 304L. Grade 321 may also be used as an alternative to 304 if heavy section welding is required and post-weld heat treatment is not possible. Machining A “Ugima” improved machinability version of grade 304 is available in bar products. “Ugima” machines significantly better than standard 304 or 304L, giving higher machining rates and lower tool wear in many operations. Dual Certification It is common for 304 and 304L to be stocked in “Dual Certified” form, particularly in plate and pipe. These items have chemical and mechanical properties complying with both 304 and 304L specifications. Such dual certified product does not meet 304H specifications and may be unacceptable for high temperature applications. Applications Typical applications include: · Food processing equipment, particularly in beer brewing, milk processing & wine making. · Kitchen benches, sinks, troughs, equipment and appliances · Architectural panelling, railings & trim · Chemical containers, including for transport · Heat Exchangers · Woven or welded screens for mining, quarrying & water filtration · Threaded fasteners · Springs Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)​

Stainless steel butt weld elbow is seam pipe fittings, it is generally used in relatively large diameter stainless steel elbow, and wall thickness is thin. Stainless steel butt weld elbow has certain corrosion resistant, heat resistant, wear-resisting performance, it is widely used in different fields and industries, usually used in power plant, chemical, oil and other equipment. Stainless steel butt weld elbow, the process is the same as the tube of stainless steel plate by stamping die stamping into half a piece of ring elbow, then two and a half block shape bend to group of butt welding forming, production and processing according to the process. Stainless steel butt weld elbow in the welding process, after heating, can release carbide, release the carbide will affect the performance of the stainless steel elbow, reduce corrosion resistance and mechanical properties, and sclerosing after welding is bigger, easy to crack, so need to pay attention to matters in the process of welding and method, ensure the good use value and performance. If using the same type of chromium stainless steel elbow electrode welding, must be above 300 ° C, preheating and slow cooling off around 700 ° C, after welding if cannot undertake the weldment heat treatment after welding, should choose the chromium nickel stainless steel elbow. Different kinds of electrode in use have different performance and characteristics, in use according to the needs of the corresponding selection, ensure the quality of the welding of stainless steel elbow. Steel plate made of stainless steel elbow in the welding process using dc power; When used at the same time should be kept dry, lest cause weld stainless steel elbow increased carbon content and affect the welding quality. In order to improve corrosion resistant stainless steel elbow and weldability, select elements increases the stability of the (Ti, Mo) such as steel, chromium than the weldability of the stainless steel plate is better. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

How does chloride corrode stainless steel In the chloride medium, the stainless steel pipe is often subject to local corrosion is mainly point corrosion and corrosion corrosion two. Corrosion mechanism of stainless steel The reason for corrosion resistance of stainless steel pipe is because there is a layer of passivation film on the surface. When this passivation film is destroyed and lacks the conditions or capabilities of the passivation, the stainless steel pipe is corroded. If the corrosion area is concentrated at a specific point and a corrosive pits are developed into the depths, Tube other surface is still passive, this corrosion phenomenon is the point of corrosion. Stainless steel forms point corrosion conditions Only in a specific corrosive medium, the stainless steel pipe will form a point of corrosion. When the halogen ions and oxidants (such as dissolved oxygen) are present in the medium, point corrosion is liable to occur. Most of the corrosion of the stainless steel pipe equipment caused by chloride and chloride ions, especially hypochlorite (present in the bleach), the more corrosive. Other halogen ions, bromide will also cause point corrosion, and fluoride and iodide solution, the occurrence of point corrosion of stainless steel tube tend to be smaller. If the chloride solution contains copper, iron and mercury and other metal ions, the corrosion is particularly serious, the risk of corrosion at the point of occurrence of equipment will be greater. Corrosion characteristics of stainless steel Stainless steel pipe corrosion occurs when its shape features are the following: 1, most of the stainless steel tube surface almost no corrosion, and some even bright as new, only local corrosive holes. 0Cr18Ni9Ti stainless steel in 10% FeCl3.6H2O solution, room temperature soaking 2.5h after the appearance of the point of corrosion (A) the original appearance (dents) after soaking (b) (a) After the dents are broken on the top of the wheel, the surface of the wheel of the air compressor made of 1Cr13 martensitic stainless steel The appearance 2, stainless steel pipe looks like no pitting and like to hit the dents, and the dents are metallic luster, but if the broken dents, the following is a serious pitting pits. The pitting appearance of duplex stainless steel in 10% FeCl3.6H2O aqueous solution at room temperature for 47h 3, the point of corrosion is not only small size, but also by the corrosion products covered, similar to pollutants. After wiping the contaminants, the pits will be exposed. 1Cr18Ni9Ti stainless steel made of pyrithione autoclave liner in the use of pitting pits 4, sometimes stainless steel pipe and part of the environment after the combination of reaction, the point of corrosion will be pagoda-like morphology. 1Cr18Ni12Mo2Ti stainless steel in 10% FeCl3.6H2O solution, 50 ℃, soak for 48h after the appearance of the surface morphology of corrosion.

Stainless steel is one of the most important inventions in the 20th century, during the past hundred years of development and research has formed a series of more than 300 brand of steel grade. Visible, as an important material of stainless steel becomes more and more important for people, it is installed in engineering materials plays a role can not be ignored. Stainless steel elbow, of course, as a kind of pipe installation accessories products, plays an important role. As we all know, stainless steel elbow is different from carbon steel elbow is the main material of different. The chemical composition of the stainless steel elbow will keep the bend surface for a long time without rust. Then what metal elements can make the stainless steel elbow so good with carbon steel elbow it? We all know that the industrial grade stainless steel elbow is austenitic stainless steel. Austenitic stainless steel is greater than 18%, and chromium containing 8% nickel, of course, which also contains a small amount of copper, titanium, nitrogen and other elements. This kind of steel contains a large amount of nickel and chromium to make steel at room temperature in a state of austenite. Visible, chromium and nickel in stainless steel play an important role. Now we talk about the role of chromium in the stainless steel elbow: stainless steel elements is decided only one is Cr, so far, no chromium stainless steel, add chromium in stainless steel, the contradiction of internal corrosion resistance, resistance to damage the direction of development. The addition of chromium content in the steel reached more than 10 in order to form chromium passivation protective membrane stability, protection of steel against atmospheric corrosion, corrosion resistance of stainless steel increased with increasing chromium content. Then we talk about the role of nickel in stainless steel elbow: nickel is an excellent corrosion resistant material, which is an important alloying element in alloy steel. Nickel in stainless steel to join, the crystal structure changes from cubic face centered cubic structure, the steel is easy to form a single organization (austenite) steel, has not formed the micro battery capacity, so as to avoid being the main reasons for the corrosion of steel. In stainless steel, if the nickel can reach 24%, the microstructure of pure austenite can be obtained, and the corrosion resistance of the steel in some medium can be significantly changed by 27%. However, nickel and chromium exist in stainless steel, nickel can play a lot of valuable role in stainless steel. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

The processing of the elbow is easy to produce the following quality defects, especially in the bending of the elbow. (1) thinning of wall thickness, wrinkling, such as the outside of the bending deformation zone will produce thin wall thickness. The maximum deformation of the parts in the maximum deformation, when the thin excessive lead to rupture of the pipe. From the point of view of deformation mechanics, the ring is a problem which is too large. If the inside of the bending deformation zone will produce wall thickness increase. If the degree of deformation is too large, the inner wall of the tube will be unstable and thick, severe wrinkling. Therefore, the instability is not only under the effect of tensile stress will appear, under the effect of stress, the same instability problem. Such defects occur in the wall thickness of the tube bending. (2) section shape distortion in the elbow bending process, if you do not take the necessary measures (such as in the tube filler or placed mandrel support), elbow cross section after bending in the absence of internal support can easily become oval. Therefore, it is very important to prevent the production of the above defects in order to select reasonable technological process and take necessary technological measures. Production practice shows that the elimination or reduction of quality defects, in order to meet the requirements of the use of pipe fittings, is the key process of processing. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

317LMN and 317L are austenitic stainless steel containing molybdenum. Compared with ordinary chrome-nickel austenitic stainless steel (such as 304 stainless steel), its resistance to chemical erosion better, high temperature environment, the fracture stress intensity stronger, better ductility. The combination of molybdenum and nitrogen improves the pitting resistance and resistance to pitting of stainless steels, especially in high temperature environments containing acidic compounds, chlorides and sulfides. Nitrogen while improving the strength of stainless steel. Chemical Composition The chemical composition of grade 317L stainless steel is outlined in the following table. Element Content (%) Iron, Fe Balance Chromium, Cr 18-20 Nickel, Ni 11-15 Molybdenum, Mo 3-4 Manganese, Mn 2 Silicon, Si 1 Phosphorous, P 0.045 Carbon, C 0.03 Sulfur, S 0.03 Corrosion resistance of stainless steel 317L and 317LMN stainless steel withstand the atmosphere and mild corrosive ability, in addition to strong oxidizing acid (such as nitric acid). 317LMN and 317L stainless steel anti-sulfuric acid solution corrosion better. Its corrosion resistance increases with the increase of molybdenum content of stainless steel. These stainless steels can withstand up to 5% sulfuric acid at temperatures up to 120 ° F (49 ° C). At temperatures below 100 ° F (38 ° C), these stainless steels have excellent corrosion resistance and are resistant to higher concentrations of solution corrosion. However, application testing should take into account specific operating factors that may affect corrosion behavior. These stainless steels are more resistant to the formation of concentrated gases than conventional stainless steel 316 during the process of concentration of sulfur-containing gases. The concentration of acid has a significant effect on the corrosion rate in such an environment and should be carefully determined according to the specific application test. The following table shows the corrosion resistance of annealed 317LMN and 317L samples in a variety of solutions, all of which are related to the processing industry and ASTM testing. This table lists the relevant data for stainless steel 316L and stainless steel AL276 for comparison. Corrosion Resistance in Boiling Solutions and ASTM Tests Test Solution Corrosion Rate in Mils per Year (mm/y)  for Cited Alloys Alloy 316L Alloy 317L Alloy 317LMN Alloy 276 20% Acetic Acid 0.12 (<0.01) 0.48 (0.01) 0.12 (<0.01) 0.48 (0.01) 45% Formic Acid 23.41 (0.60) 18.37 (0.47) 11.76 (0.30) 2.76 (0.07) 10% Oxalic Acid 48.03 (1.23) 44.90 (1.14) 35.76 (0.91) 11.24 (0.28) 20% Phosphoric Acid 0.06 (0.02) 0.72 (0.02) 0.24 (<0.01) 0.36 (0.01) 10% Sulfuric Acid 635.7 (16.15) 298.28 (7.58) 157.80 (4.01) 13.93 (0.35) 10% Sodium Bisulfate 71.57 (1.82) 55.76 (1.42) 15.60 (0.40) 2.64 (0.07) 50% Sodium Hydroxide 77.69 (1.92) 32.78 (0.83) 85.68 (2.18) 17.77 (0.45) ASTM A262 Practice B (FeSO4H2SO4) 26.04 (0.66) 20.76 (0.53) 17.28 (0.44) 264.5 (6.72) ASTM A262 Practice C (65% HNO3) 22.31 (0.56) 19.68 (0.50) 16.32 (0.42) 908.0 (23.06) ASTM A262 Practice E (Cu•CUSO4•H2SO4) Pass Pass Pass Pass The low carbon (less than 0.03%) of these alloys effectively prevents sensitization to intergranular corrosion during thermal processes such as welding or forging. The higher chromium contents of 317LMN and Alloy 317L stainless steels also provide superior resistance to intergranular attack. It should be noted that prolonged exposure in the range 800 to 1400°F (427-816°C) can be detrimental to intergranular corrosion resistance and may also cause embrittlement due to precipitation of sigma phase. The higher nitrogen content of the 317LMN alloy retards the precipitation of sigma phase as well as carbides. Pitting Resistance Equivalents Alloy PRE Alloy 316 25 Alloy 317L 30 Alloy 317LMN 38 Alloy 625 52 Alloy C276 69 High molybdenum and nitrogen contents can significantly improve pitting resistance as illustrated in the preceding table of Pitting Resistance Equivalents (PRE). The PRE is based on the results of corrosion tests in which it was found that nitrogen was 30 times more effective than chromium and approximately 9 times more effective than molybdenum in enhancing chloride pitting resistance. The temperature of the onset of crevice corrosion as determined in a modified AST G-48B test is a useful means of ranking the relative resistance of stainless and nickel-base alloys. The Critical Crevice Corrosion Temperatures table that follows demonstrates that crevice corrosion resistance for austenitic stainless steel tubing increases with the alloy’s molybdenum and nitrogen content. Crevice Corrosion in a Simulated  FGD System Environment Alloy Weight Loss (g/cm2)  for Tests* at Cited Temperatures 24°C (75°F) 50°C (122°F) 70°C (158°F) Alloy 317L 0.0007 0.0377 0.0500 Alloy 317LMN 0.0000 0.0129 0.0462 Alloy 625 0.0000 0.0000 0.0149 Alloy C276 0.0000 0.0001 0.0004 *72-hour exposure based on ASTM G-48B procedure using the following solution:  7 vol.%H2SO4, 3 vol%HCI, 1 wt% CuCl2, 1 wt%FeCl3 Mechanical Properties The mechanical properties of grade 317L stainless steel are displayed in the following table. Properties Metric Imperial Tensile strength 595 MPa 86300 psi Yield strength 260 MPa 37700 psi Modulus of elasticity 200 GPa 29000 ksi Poisson’s ratio 0.27-0.30 0.27-0.30 Elongation at break (in 50 mm) 55% 55% Hardness, Rockwell B 85 85 Antioxidant properties Chromium-nickel-molybdenum steel has excellent oxidation resistance, and in the ordinary atmosphere, the temperature is not higher than 1600-1650 ° F (871-899 ° C), the scale generation rate is low. Stainless steel processing performance 317LMN stainless steel and 317L stainless steel physical and mechanical properties and conventional austenitic stainless steel similar, therefore, can be processed 304 stainless steel and 316 stainless steel method for its processing. Manufacturing Process Conventional hot working processes can be performed. The material should be heated to 1149-1260°C (2100-2300°F); however, it should not be heated below 927°C (1700°F). To optimize corrosion resistance, a post-work annealing is recommended.Machining stainless steel grade 317L requires low speeds and constant feeds to reduce its tendency to work harden. This steel is tougher than grade 304 stainless steel with a long stringy chip; however, using chip breakers is recommended. Welding can be performed using most of the conventional fusion and resistance methods. Oxyacetylene welding should be avoided. AWS E/ER 317L filler metal is recommended. Shearing, stamping, heading and drawing are possible with grade 317L stainless steel, and post-work annealing is recommended to eliminate internal stresses. Annealing is performed at 1010-1121°C (1850-2050°F), which should be followed by rapid cooling. Grade 317L stainless steel does not respond to heat treatment. Applications Grade 317L stainless steel is widely used in the following applications: · Condensers in fossil · Pulp and paper manufacturing · Nuclear fueled power generation stations · Chemical and petrochemical process equipment. Source: wilsonpipeline Pipe Industry (www.wilsonpipeline.com)

Large flange in use process due to the large flange connection when improperly or use time is too long, leak, appear this kind of circumstance the user need not worry. First look at the leak site, minimal in leak position due to the large flange clearance can’t be eliminated by injecting sealant clearance leakage. The construction method of sealing according to leak the field survey, for the realization of the limited block, by using fixed fixture tolerance leak to form a sealed chamber, injecting sealants, to eliminate leakage. Side of the clamp are made of, fixture first to satisfy large flange leak inclusive and build body large flange and pipe between the large flange connection sub large flange seal chamber as the first point. To prevent from pressure-out potential leak valve body and the large flange clearance appears to leak, the fixture and the large flange anastomotic set to the outer ring cavity injection glue. Because of the large diameter flange in the process of injection agent fixture is easy to trail large flange lateral displacement, the limit of the tooth contact card is adopted tightening measures. When operating sealant after curing, after effect observation, local injection pressure, prevent stress relaxation, closed agent injection hole again. The large flange to note: Large flange in the production and use of technical requirements and technical parameters, according to certain ways and methods of production and processing: hebei large flange 1. The large flange should be along the direction of steel rolling cut into strips, the bending welded into a circular ring, and to form the surface of the steel ring cylinder. When in the production of large flange shall not adopt steel machined directly into a large neck flange, adoption of a certain craft production and processing. 2. The production of large flange plate should be via ultrasonic testing, with no defects, guarantee the good quality and performance problems, according to certain quality requirements of the production and inspection, ensure the quality of the production and use of the steel plate no problem. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Eccentric reducer in the actual production add different elements of different functions and intensity, using certain production standard and the way to add, in which the use of a certain performance. Eccentric reducer characterized by carbon intensity is significantly higher than the same amount of carbon steel, has good toughness and plasticity, good weldability and corrosion resistance, etc. In order to improve and enhance the performance of the steel on the basis of the carbon steel to join other alloying elements, such as silicon, manganese, chromium, nickel, tungsten, vanadium, titanium, etc., this kind of steel is alloy steel. Eccentric reducer according to difference of alloy elements, have different properties, such as high wear resistance, corrosion resistance, good low temperature resistance, good special features such as high magnetic. The center of the eccentric reducer as the main body section, straight pipe ends for eccentric, main body between a straight pipe section and eccentric reducing transition section, eccentric reducer the bottom line is straight line remains unchanged; Eccentric reducer of preparation methods are classified using multiple sets of mould, eccentric reducing in the metal tube directly, first set aside the main section in the middle of the metal one, again according to the request of tapered Angle, using multiple sets of hierarchical mold molding, step by step to suppress and into. Using this invention method processing eccentric reducer, the whole root eccentric size head without weld; Eccentric reducer as a dedicated pipe, used in corrosive strong liquid, can prolong the service life of the eccentric reducer, especially used for downhole eccentric water distributor’s shell, because there is no seam, not in the joint corrosion cracking; Flexible production technology, processing any straight pipe diameter, eccentric any longer eccentric reducer. The size of the eccentric reducer pipe of different connections, is suitable for different industries are different. In electric power, mining, metallurgical and other industries, the material of the conveyor, output, are using at close range, high pressure conveying pipeline under considerable pressure, and sustained serious wear and tear, single material pipeline is very difficult to meet the requirements of this condition, especially the elbow, concentric reducer, such as stamping elbow pipe fittings, by considering its use of security, and service life, focus on improving pipe lined with toughness, impact resistance, and abrasion resistance. At the same time also want to consider the integrated intensity of the pipe and elbow problems. Eccentric reducer before bonding, use dry cloth to bell mouth and socket lateral wipe the handle, when the surface with oil pollution must be with acetone to wipe clean, have the following points to note: 1, control diameter: DIN, 3 a/IDF standards, ISO standards; 2, the international industry standard: DIN, ISO, SMS, 3 a, IDF, etc; 3, the product material: 304, 316, 316 l stainless steel; Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

On both ends of the reducer is also called the reducer, pipe diameter, used to connect different diameter tubes or variable diameter flange. Concentric reducer at both ends of the tube, circle, on the same axis diameter changes, in terms of axis of pipe position, the position of the pipe is changeless, commonly used in gas or liquid vertical pipe diameter changes. Price according to the diameter and the material is not different, has the certain calculation formula of the specifications of the reducer with the diameter of the big times the diameter of the small mouth, such as a diameter of 400 and 200, respectively, with 400 * 200, said the wall thickness also affects the price of their products. Products are pided into concentric reducer and eccentric reducer, used for different diameter of pipe connection, in the transition between the main and branch pipe bend them is required. Concentric reducer is big is small sip concentric circle, in the straight pipe connection, can’t change the direction of the pipeline, two circle is not concentric reducer, eccentric reducerprocessing technology is relatively concentric reducer some hard, so the price is in the process of production. Carbon steel material, the material such as stainless steel, carbon steel reducer usage of the biggest, the general said carbon steel products cheaper price, accessories production use, because of the carbon steel as the raw material price is not expensive, so the production cost and product price is very cheap, the price of the bend is not fixed, calculated according to the size of the diameter, the bigger the diameter of the product price is more expensive, so at the time of purchase products to clear the required diameter and material of the wall thickness, in order to get the most reasonable reducer quotation. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Stamping elbow has certain corrosion (oxidizing acid, organic acids, cavitation), heat-resisting and wear-resisting performance. Usually used in power plant, chemical, oil and other equipment. Stamping elbow poor weldability, welding, heat treatment conditions should be paid attention to and choose suitable welding electrode. The corrosion resistance of the stamping elbow depends on the alloy element content in the steel. Chromium stainless steel stamping elbow is get the corrosion resistance of the basic elements, while about 1.2% chromium content in steel, chromium and oxygen in erosion media effect, in the steel surface to form a thin layer of oxide film (since the passivation film), but to prevent further erosion of steel substrate. Elbow pipes with different production technology and processes, according to certain conditions is needed in processing production and processing, the different nature of the elbow pipe fittings some matters need attention in the process. For alloy elbow, if do alloy long radius elbow, must first to the selected of the specifications of the steel tube, pipe material, selection of quality steel pipe production. Alloy elbow has certain hole enlargement ratio, through theoretical calculation, the general hole enlargement rate is between 33% and 35%, push back. Short radius of 219 mm hole enlargement rate was 50%. Choose good raw materials, according to the alloy elbow materials specifications, then consider the radius of curvature, for example, the 90 ° elbow, through its curvature can calculate how much material can work out the 90 ° elbow. Through the theoretical calculation can be calculated, then based on the length scale. The final push materials for thermal system. Because of some elbow after improper handling, will be distorted, this is not allowed. Stamping elbow won’t produce corrosion, pitting, corrosion or wear and tear. Stainless steel is used in metal materials in one of the highest material strength. Because stainless steel has good corrosion resistance, so it can make structure parts permanently maintain the integrity of engineering design. Chromium stainless steel stamping elbow also has high mechanical strength and extensibility, easy processing and manufacturing of parts, can be satisfied with the architect and structural design staff needs. All metal and atmospheric oxygen in the reaction, formed in the surface oxide film. Unfortunately, in the ordinary carbon steel oxidation of iron oxide is formed on the inheritance, kept expanding rust, ultimate forming holes. Can use paint or resistant to oxidation of the metal (for example, zinc, chromium and nickel) on plating to ensure that the surface of carbon steel, but, as we know, the protection is only a thin film. In addition, after have a haircut is usually large front end diameter, through plastic mould for plastic. The whole model is actually a press, want to have a set of mould, two and a half arc, the upper one. After the plastic outer diameter to reach the size of the finished product. Wall thickness in the wall thickness of incoming material control. Elbow and pipe wall thickness tolerance is the same, are the plus or minus 12.5%. Commonly used alloying elements except chromium and nickel, molybdenum, titanium, niobium, copper, nitrogen, etc, in order to content with various USES of stainless steel stamping elbow organization, and functional requirements. Stamping elbow making matters needing attention when using electrode should be kept dry, titanium calcium type should be 1 hour after 150 ℃ drying, low hydrogen type should be 1 hour after the 200-250 ℃ drying (not sticky oil and other dirt, lest cause weld increased carbon content and influence the welding quality and mechanical properties. Sclerosing after welding is bigger, easy to crack. If using the same type of electrode welding, must be above 300 ℃ preheat and 700 ℃ or so slow cooling after welding. If it’s unable to weld heat treatment after welding, should choose chromium nickel stainless steel electrode. In order to improve the stamping elbow corrosion resistance stability element Ti, Nb and Mo, weldability is better, using the same type of chromium stainless steel electrode, should be above 200 ℃ preheat and around 800 ℃ tempering treatment after welding. If cannot undertake the weldment heat treatment, should choose chromium nickel stainless steel electrode. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Stainless steel has been successfully and widely used in a variety of marine environments, because in order to stainless steel in the seawater environment long-term corrosion resistance, the need for a very complex stainless steel processing technology. Austenitic stainless steels, martensitic stainless steels have long been used in the manufacture of navigational power units on superheater pipes and turbine blades. In addition, these stainless steels are also used to make large-capacity chemical containers on ocean-going vessels, and the use of these devices is sometimes different from the conditions used by the land chemical plant. Many grades of stainless steel can be used very well in marine environments, but different grades are sensitive to stress corrosion cracking. Martensitic stainless steel on behalf of 410 and ferrite stainless steel on behalf of 430, if in the marine environment, a few months time will rust. However, such uniform rust can be removed by mechanical grinding. The more popular stainless steel is austenitic stainless steel because the steel is more resistant to corrosion. But the time is too long, the same will be black. Also can be polished to remove these blacks. And the steel stainless steel in the water generally do not occur evenly rust, so do not worry too much. Stainless steel leaves The use of stainless steel in marine environment The stainless steel components in the propeller The marine vessel’s propeller can be made of cast stainless steel CF-8 (similar to 304 stainless steel). When the vessel stops sailing, from the propeller spindle through the bearing to the hull, constitute a conductive metal circuit. Cast stainless steel, similar to the chemical composition of 410 stainless steel, is also often selected as a propeller, and is also widely used in icebreakers. With the development of stainless steel technology, also has a compound austenitic – ferritic stainless steel 20Cr-8Ni-3.5Mo to cast large-scale propeller on the ocean wheel (weight 3000kg). Often in the port operations of the vessel, the propeller is vulnerable to the impact of debris on the sea and accelerated damage. So the austenitic stainless steel as raw material made of the propeller can be straightened or welded way to repair, so the material is to consider this aspect. Stainless steel components in the pump When the centrifugal pump operating environment is the ocean, such as the pump has a stainless steel components, equipment, the reliability will be significantly increased. Seawater CF-8M cast stainless steel impeller (similar to 316 stainless steel) and 316 stainless steel as the spindle, the reliability is very good. If the pump does not work, it is likely to be crevice corrosion and point corrosion. So you can use a more lively and rusty cast iron to make a considerable wall thickness of the pump, so cast iron in the downtime will have a cathodic protection of the pump. When the pump work, the cast iron box under the protection of the cathode will be able to make the next rust steel, but the flow of water to be cathodic protection. In addition to long-term work of the pump is best for seawater and fresh water, the use of different equipment. Bulk containers Stainless steel is also often made of bulk containers, such as liquefied natural gas (LNG), chemicals, beverages and so on. Generally use 304L stainless steel to make the shipment of LNG containers loaded, the purpose is not to corrosion but to pay attention to the low temperature of the stainless steel mechanical properties. The containers of marine chemicals generally take into account the corrosion resistance of stainless steel, which is contrary to the storage and transportation of terrestrial chemicals. If the vessel is an ordinary non-scheduled freighter, the container carrying the chemical can also carry other items such as acetic acid, bad pulp or xylene. Usually 316L stainless steel as raw material to make the valve, cargo pump, tube, heating coil and the container itself. The container can be made of stainless steel or made of carbon steel in a 0.06-0.08in (1.5-2.0mm) stainless steel plate. However, before use, be sure to carefully check the container stainless steel plate is defective and thorough cleaning and passivation treatment. Stainless steel components in heat exchangers Austenitic stainless steel pipes are now widely used in forced water circulation systems for coolers and power plant steam condensers, which are not suitable for use with copper alloy because of their high levels of contamination. 316 stainless steel is more appropriate to use. In the coastal and harbor areas, a large number of foreign agglomerates and sludge into the condenser pipe, very prone to serious obstacles, then we must take measures to exclude. A reasonable measure is to use a rubber ball to circulate through the pipe, because the rubber ball can produce squeeze to clean up the pipe wall. When the flow rate of seawater is about 1m / s, it can effectively prevent the inhalation of marine organic debris, so that the condenser pipe can not produce point corrosion. Unlike other alloys, the condenser duct made of stainless steel is not limited by the maximum flow rate but is related to the economic effect of the entire pump unit. O-ring Series-type electrical connectors and associated O-ring positioning devices are usually made of 304 or 316 stainless steel, especially marine and military engineering. This effect is very good. O-shaped seal can be through the hull, aluminum frame to be some factors to obtain cathodic protection. But once there is no cathodic protection, the O-ring is so bad (or even weeks) that it will lose its function because of crevice corrosion. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Stainless steel lap joint stub end is a tensile or compression edge production, method of making forming vertical edge height of the. Mainly pided into convex curve lap joint stub end and concave curve lap joint stub end. The stress and deformation properties of convex curve lap joint stub end is similar to the shallow drawing, the deformation degree is denoted by Kfb=r/R0; the degree of lap joint stub end coefficient Kfb=r0/ deformation concave curve lap joint stub end (r0+b) to said, when the center of the curve angle smaller than 180 DEG, Kfb=Kfk α/180°. Stainless steel lap joint stub end is generally pided into stretch lap joint stub end and compression lap joint stub end deformation zone, the elongation of the lap joint stub end is blank, stress to pull in cutting under the action of the tangential deformation, ultimate deformation degree under the deformation zone cracking limit. While the compression lap joint stub end radius is in addition to near the region near the vertical side of the root of metal deformation completely, the other part of the blank deformation zone is tangential compressive deformation of tangential compressive stress under the action. Stainless steel lap joint stub end due to the long time work, there will be fatigue and wear, because of these problems, so the material should be stainless steel lap joint stub end has high bending strength and contact fatigue strength, the core is to have good strength and toughness. If the work is stable, there is no strong impact of the gear, the use of 40Cr, 40MnB, such as low carbon steel or medium carbon low alloy and other materials. If the work condition is not good, we will load the quality of material properties and heat treatment of stainless steel lap joint stub end has required that we must choose some alloy steel as raw material, so as to ensure the normal operation of equipment. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)