Pipe Fittings Knowledge

Brief introduction about the classification of steel pipe elbows  Brief introduction about the classification of steel pipe elbows  According to the fluid direction of the pipelines, steel elbows can be divided into different degrees, such as 45 degree, 90 degree,180 degree, which are most common degrees. Also there has 60 degree and 120 degree, for some special pipelines. According to the raw material, the steel pipe elbows can be divided as seamless pipe elbow and welded pipe elbow. Here we’d like to share some knowledge about the seamless steel elbow and welded steel elbow.  The difference between seamless elbows and welded elbows Seamless elbows are made of seamless steel pipes through hot pushing, pressing or extrusion processes, and there are no welds on the elbows.In general, welded elbows smaller than DN600 are made of welded steel pipes, are made in the same process as seamless elbows. But there is a welded seam on the elbows. Welding elbows larger than DN600 are made of steel plates, and there will be 2 welds. If you need the seamless elbows when the size is above DN600, please inform in advance, we can also produce them. JS FITTINGS will show you the difference between seamless elbows and welded elbows in raw materials, manufacturing process, performance, appearance, size, application, cost and price. How to make seamless elbow The production of seamless elbows mainly uses hot pushed technology.The hot pushed elbow forming technology is to use special elbow pushing system core machine, mold and heating device, to set on the mould of billet in pushing forward movement, under the impetus of the machine in motion is heated and hole enlargement and forming process.  The hot pushed elbows have a good appearance, uniform wall thickness and continuous operation, they are suitable for the characteristics of mass production. Thus, the hot pushing technology becomes the main forming methods of carbon steel, alloy steel elbows, and also applied in some specifications of the stainless steel elbows. How is Welded elbow made? The raw materials of welded elbows are welded steel pipes and steel plates. Normally, the elbows’ diameter below DN600 are produced by welded steel pipe. The diameter more than DN600 requires steel plates. The first step of producing the welded elbow is bending the steel plates, then welded into circular. Welded steel elbows have the characteristics of high production efficiency, low cost and saving material.

How do the ASME B 16.9  60 inch pipe elbows be made? Methods of produce steel pipe elbows Steel pipe elbow is a kind of pipe fittings used for pipe turning, there are 90 degree elbows, 45 degree elbows and so on. It can be produced according to the engineering needs. Because of the different materials and different pressures, the manufacture process of pipe elbow is also different. So far, steel pipe elbow manufacturers commonly use 4 methods to produce seamless pipe elbows: hot-pushing, stamping,  extrusion and butt Welding. Hot- pushed Pipe Elbows The hot-pushing is a process used to produce seamless pipe elbows, using a elbow-push machine, a core mold and a heating device, the blank sheathed in the mold is pushed to run forward under the elbow-push machine. It’s a process of heating, expanding, diameter, and bending. The deformation characteristics of the hot-pushing elbows are determined according to the law of the metal material remains unchanged before and after plastic deformation. The diameter of the pipe blank is determined when the pipe is adopted. The diameter of the pipe is smaller than the elbow, to thinning out the rest of the body by expanding the diameter. Then the thickness of pipe elbow is uniform. The pipe elbows made by pushing machine have beautiful appearance and uniform wall thickness. The pushing machine is suitable for mass producing. So the main production process of general Carbon steel elbows and alloy steel elbows is hot-pushing which also used in certain specifications of stainless steel elbows forming. Stamped Pipe Elbows The stamping pipe elbow manufacturing process is the earliest application of the mass production of seamless elbow molding process which have been replaced by hot-pushing in common use. However, when the pipe elbow quality is small, some specifications and wall thickness is too thin or too thick , and with other special request, the factory will choose the stamping process. In the forming process, the diameter of blank pipe should be same with the finished pipe elbow, and be stamped into the forming of pipe elbows. Stamping process is divided into cold stamping and hot stamping, we select the manufacturing process according to the material. The stamping process is not as good as hot-pushing, especially the quality and appearance. In the forming process, the elbow outer-arc is in tension. There is no extra material to compensate the outer-arc, so the wall thickness at the outer-arc is about 10% thinner than before. However, due to the characteristics of unit production and low cost, the stamping process is suitable for small batch production of high-pressure thick-wall elbows.

Differences between steel pipe bends and pipe elbows Steel pipe bend is a bending pipe that used to change the pipeline direction. It is similar to pipe elbow, but differently, pipe bend is longer than elbow and usually manufactured for the specific needs.So it depends on different bending radius (R) to distinguish bend and elbow.In case the bending radius is more than 2 times of D (diameter), it is pipe bend.In case bending radius in 1D or 2D, it is an elbow. (short radius elbow and long radius elbow). How does the steel pipe bend make? The pipe bend is bent by a set of bending equipment with two processes: Cold simmering and hot pushing. (Including bending, squeezing, pressing, forging, machining, etc) Differences between Steel Pipe Bend and Elbow Pipe bend and elbow both for change the pipe direction, still there are a lot of differences in the below aspects:Bending RadiusManufacturing ProcessesDifferent costApplication scope Bending Radius of Bend and Elbow As we talked above,Steel pipe bend radius: Above 2 times of D, so there are 2D, 2.5D, 3D, 5D, 6D, 7D or 8D pipe bend.Steel pipe elbow radius: R=1D or R=1.5D or 2D. Below 1.5D is a short radius elbow, and more than 1.5D but not over 2D is a long radius elbow.R is the radius of curvature; D is (elbow or bend) pipe diameter. As the above picture, CLR could be in 1D, 1.5D, 2D, 3D, 5D, etc. Different manufacturing processes Bend: Could be bend directly from a finished pipe with cold bending processes, to different degrees.Elbow: Shall be made according to standard manufacture procedures, with hot finishing or hot bending, to a certain degree, 45°, 90° or 180°. Cost different Professional manufacturer of asphalt machines. Our sales and R&D team have over 10 years’ experience to focus on asphalt distributor, synchronous pavement surface vehicles and other road machinery and equipment.  Different applications scope Bend: Compatible with slower liquid and lower pressure.Elbow: Compatible with high pressure and rapid liquid.Sometimes elbows must be used in narrow sections because the radius of curvature of the elbow is small, generally 2D, but the pipe bend could be up to 40D. We supply steel pipe bend with below ranges: Manufacturing standard: AISI B16.49Material: Carbon steel, Alloy steel, Stainless steelMaterial standards: ASTM A234 WPB, WPC, WP1, WP5, WP9, WP11, WP22, WP91; ASTM A403 304/304L, 316/316L.Outer Diameters: 1/2'' to 48''. DN15 to DN1200Radius range: R=2D, 2.5D, 3D, 5D, 6D, 7DDegree range: 45 degree, 60 degree, 90 degree and customized.Wall thickness: SCH 10, SCH 40, SCH80Coatings: Black paint, galvanized, epoxy coated, 3PE, FBE

Steel Pipe Demisions-SCH 10 Internal and external diameters, areas, weights, volumes and number of threads for schedule 80 steel pipesBased on ASTM A53 - Standard Specification for Pipe, Steel, Black and Hot-Dipped, Zinc-Coated, Welded and Seamless. ASTM A53 pipe  - also referred to as ASME SA53 pipe - is intended for mechanical and pressure applications. Can be used in steam, water, gas and air lines. Suitable for welding and forming like coiling, bending and flanging.· 1 in2 = 645.2 mm2 = 6.452 cm2 = 6.452x10-4 m2· 1 ft (foot) = 0.3048 m Related FAQS Steel Pipe Dimensons - Schedule 40Differences between steel pipe bends and pipe elbowsWhat's the features of seamless carbon steel tee fittings and pipe reducers?Industrial Pipe Fittings Standards

What's the features of  seamless carbon steel tee fittings and pipe reducers? Carbon steel tee fittings are generally used for regulating valve devices and used for draining.Concentric reducers  are beneficial to fluid activities and have less interference to fluid flow regimes during reducing diameters.  Seamless tee for liquid and gas pipe, using concentric reducer to reduce diameter. Because the eccentric reducer is flat on one side, it is convenient for exhausting and draining, which is convenient for operation and maintenance. Therefore, the liquid pipeline of the horizontal device generally uses an eccentric reducer.The reducer is also called the size head. The diameters of the two nozzles are different. They are used to connect pipes or flanges of different diameters for diameter reduction. The nozzle of the concentric reducer, the center of the circle is on the same axis, when the diameter is reduced, and the orientation of the tube is calculated by the axis, the orientation of the tube is constant, and is generally used for gas or straight liquid pipe diameter reduction. The eccentric reducer is internally cut at the ends of the two nozzles and is generally used for horizontal liquid pipes. Butt welding tee is a steel hot press forming or forging forming elbow. Its connection method is to directly weld the tee and the steel pipe. The main production standards of the butt welding tee are generally GB/T12459, GB/T13401. , ASME B16.9, SH3408, SH3409, HG/T21635, HG/T21631, SY/T0510.

Industrial Pipe Fittings Standards The standardization systems are very important, especially when the  consequences of a product failing are dire–like in an engineering project. The standards help us to know what  we’re getting will perform as our expect, and the product won’t let us down.Pipe fitting standards said how fittings were designed, how they were constructed, and how they can be expected to perform. Some of the characteristics that pipe fitting standards cover include: SizePressure-temperature ratingsDesignMaterialsCoatingsMarkingThreadingEnd connectionsDimensions and tolerancesPattern taper Types Of Industrial Pipe Fitting StandardsThere are a number of organizations that specify pipe fitting standards. Some of the most well-known include: ANSI: The American National Standards Institute This private, non-profit organization coordinates the U.S. voluntary standardization and conformity assessment system. ANSI’s ‘schedule numbers’ classify wall thicknesses for different pressures uses. ASME: American Society For Mechanical Engineers ASME is one of the most respected organizations when it comes to developing standards and codes. ASTM International: American Society for Testing And Materials One of the largest voluntary standards development organizations, ASTM develops and publishes voluntary standards on the basis of materials, products, systems and services. Its standards include pipes, tubes and fittings. Welcome to contact us with your BOQ and we can ship globally with short deliver time.

Seamless pipe fittings Characteristics Functions of seamless reducers Carbon steel tees (pipe fittings) are generally used to adjust the valve to facilitate drainage. The concentric reducer facilitates fluid activity and has less interference with fluid flow at the time of variable diameter. The diameter of the two ends of the reducer is different, and it is used to connect steel pipes or flanges of different diameters to reduce the diameter. The two nozzles of the concentric reducer have the center of the circle on the same axis. When the diameter is changed, the orientation of the pipe is unchanged according to the axis. Generally, the orientation of the steel pipe is constant, and it is generally used for gas or straight liquid pipe diameter reduction. The eccentric reducer is internally cut at the ends of the two nozzles and is generally used for horizontal liquid pipes. Standard of Butt welding Tees Butt welding tee is the connections of hot stamping or forging forming of steel plate. The connection method is to directly weld the tee and steel pipe. The main production standards of butt welding tees are generally GB/T12459, GB/T13401, ASME. B16.9, SH3408, SH3409, HG/T21635, HG/T21631, SY/T0510. Related information of seamless Tees Butt welding tees generally have equal-diameter tees, different-diameter tees, etc. The materials are carbon steel, alloy steel and stainless steel. Carbon steel tee When the chromium content of the steel reaches 1.2%, the chromium reacts with the oxygen in the corrosive medium to form a thin oxide film (self-passivation film) on the steel surface. The seamless tee can prevent further corrosion of the steel tube. In addition to chromium, commonly used alloying elements include nickel, molybdenum, titanium, niobium, copper, and nitrogen to meet various applications.

What is the most effective inspection method for seam pipe elbow? X radiation detection There are six main types of defects in the welding process of carbon steel seam pipe elbows: 1 poor fusion: not welded, not fused; 2 crack: hot crack, cold crack; 3 holes: pores, shrinkage holes; 4 inclusions: Slag inclusion, tungsten trapping;5 poor forming: undercut, burn through and welding, etc.; 6 other defects.X Radiation detection mainly detects the first five categories.Radiation detection is one of the important methods of conventional non-destructive testing. It is an important technology to ensure the quality of welding. The test results will be used as an important basis for the analysis and quality assessment of weld defects. The use of computer to analyze and identify the X-ray detection results can greatly improve the work efficiency, effectively overcome the misjudgment or missed judgment caused by the difference in technical quality and experience of the judges and the external conditions in the manual assessment, so that the judgment process is objective. Chemical, scientific and standardized.Radiation detection is only suitable for detecting internal defects in materials or components.

Why does the tee need to do the blasting before painting? Before painting, pipe tees must do the blasting. The blasting process adopt compressed air to form a high speed jet beam, spraying the material on the surface of the tees, make the appearance of tees changes. Due to the impact and cutting from spraying material, the surface of tees will gain some cleanness and different roughness, improving the mechanical properties of tee surface.The quality of blasting will affect the adhesion and appearance of the coating, the moisture resistance and corrosion resistance of the coating. If the blasting not done well, the rust will continue spread under coating, causing the coating falling off. After carefully cleaning the surface, the coating life will be 4-5 times longer than that only simple cleaning.

Production Process of Pipe Tees Tee is one kind of pipe fittings,formed as T-shaped. They are mainly used for change the direction of the flow. Tees are generally installed in the branch of main pipes.Pipe Tees can be used for water pipelines,oil pipelines and various liquid&chemical material pipelines, in the fields of water, oil, natural gas, construction, medicine and other engineering fields.Pipe Tees are produced according to the certain process methods and principles, ensuring good quality in actual use. First, the material was chosen by different tee sizes. Tees are formed by molds.The bottom of the mold is flat and straight, and there is a flange hole on the upper side. The pipe material is placed in the mold with fixed by a hydraulic cylinder, then fill the liquid in the pipe,make the pipe form into a 'T'. Finally, cut the end position to form bevel end.For most tees are used for welding, so the ends are mostly made as bevel end to improve the welding quality. Besides,for export, all the tees must do the surface treatment,including blasting and painting. It would be convenient for long time transportation over seas, avoiding rusting. When packing tees, we generally put smaller tees in larger TEES for saving volume. But for large size, like 24 inch, we will adopt single packing. Meanwhile, marking will be well noted with dimensions, material, heat nos, logos.For over 30 years, JS FITTINGS has been committed to producing high quality steel pipe tees, exporting over 50 countries and get good reputation. And now we still constantly open the international market with the original intention! Always do the best pipe fittings!

How to carry out anti-rust work after production? It has been verified by the research institute that the working life of the anti-corrosion layer depends on the coating type, coating quality and construction conditions. The external surface treatment of the bend affects the life of the anti-corrosion layer by about 50%. Therefore, it should be strictly in accordance with the anti-corrosion layer standard. The requirements for the appearance of curved pipes are explored and summarized from time to time, and the external disposal methods for curved pipes are improved from time to time. Different Rust removal methods 1,  the pipe cleaning Solvents and emulsions are used to clean the surface of the steel to remove oil, grease, dust, smoothing agents and similar organic matter, but it can not remove the rust, scale, flux, etc. of the steel surface, so it can only be used as an adjutant in the production of antisepsis.  2, the tool rust First, use steel wire and other things to polish the steel surface to remove loose or raised scale, rust, welding slag and so on. 3, curved pipe pickling Ordinary chemistry and electrolysis are used for pickling treatment. The anti-corrosion of curved pipe is only chemical pickling, which can remove scale, rust and old coating, and can sometimes be used as re-disposal after blasting and rust removal. Chemical cleaning can certainly bring the appearance to the inevitable cleanliness and roughness, but its anchor pattern is shallow and it is easy to cause pollution. 4, sandblasting and rust removal The jet rust removal is driven by a high-power motor to rotate the jet blades at high speed, so that the abrasives such as steel grit, steel shot, wire segment and minerals can be sprayed on the outer surface of the elbow under the effect of centrifugal force, which can completely eliminate rust, oxide and dirt. And the elbow can achieve the required average roughness under the effect of abrasive impact and friction. In order to achieve the desired descaling effect, the abrasive should be selected according to the hardness of the elbow, the original corrosion level, the required appearance roughness, the type of coating, etc., regarding the single-layer epoxy, two-layer or three-layer polyethylene coating. The inclusion of abrasives with steel grit and steel shots is more likely to reach the illusion of rusting.

why the welding Tees were fracture during working About welding of joints The joint weld seam of the large-diameter butt weld tee is on the intersecting line where the main pipe and the branch pipe intersect, and the shape and position are more complicated than the butt weld seam, and the weld quality is difficult to control during welding. According to statistics, the leakage rate of such welds accounts for 80% of the leakage rate of all process welds. The main defects are not penetration, porosity and slag inclusion. About the bevel ends of tee The weld bevel on the intersecting line is mainly formed by manual gas cutting or plasma cutting. The processing precision is not high, the groove angle is too small, and the welding process parameters are improperly selected, which will result in incomplete penetration. Another main reason for the quality defect of the welded tee is that the process is wrong, the outer groove of the branch pipe is processed into the inner groove, and the branch pipe is directly lapped on the main pipe for welding. Incomplete penetration reduces the strength of the weld. For pipes that transport corrosive media, as the production cycle increases, the heat affected zone of the weld is thinned, resulting in weld leakage. The reason for the generation of pores and slag inclusions is that the oil, rust, moisture and other impurities in the groove and the vicinity before welding are not cleaned, and the skin is not removed during the welding process. In addition, during the welding operation, the welding speed is too fast, and the welding current is too small, which accelerates the cooling speed of the weld. seline" seline"

What's the difference between the butt weld fittings and socket fittings? 1. Connection type： 1）Butt welding connection is to fix all the two parts after spot welding, of course, the welder's requirements are also slightly higher, because the butt welding needs to do 100% RT inspection under strict working conditions, Butt welding connection is common used in chemical oil, electric power, gas and steel industries. 2) Socket welding is to weld the pipe into the valve body for welding, and the shape of the internal thread connection is similar after molding. Generally speaking, carbon steel pipes and stainless steel pipes of 2" or less are used for socket welding. Stainless steel pipes are also used for butt welding below 2", such as flange flange flanges; titanium pipes, duplex steels, nickel bases. Alloys and the like are basically used for butt welding. 2. Difference1) Socket welds form fillet welds, while butt welds form butt welds. It is better to analyze the butt joints from the strength and stress state of the welds than the sockets. Therefore, in the case of high pressure grades and occasions where the use conditions are bad, the form of docking should be adopted.2) Socket welding is generally used for small diameters of DN40 or less, which is economical. Butt welding is generally used for DN40 or above. The form of socket welding is mainly used for small diameter valves and pipe, pipe fittings and pipe welding. Small-diameter pipes generally have a thin wall thickness, are easy to be misaligned and ablated, and are difficult to weld, and are more suitable for socket welding. In addition, the socket of the socket welding has a reinforcing effect, so it is also used under high pressure. However, socket welding also has shortcomings. One is that the stress condition after welding is not good, the welding is not welded, and there are gaps inside the pipe system. Therefore, the pipe system used for crevice corrosion sensitive media and the pipeline system with high cleaning requirements are not suitable. Use socket welding. Furthermore, for ultra-high pressure pipes, even small-diameter pipes have a large wall thickness, and it is possible to avoid socket welding by using butt welding.3) The former must be one big and one small in diameter before it can be inserted into the weld. The latter diameters may be the same or different. 2. The welding groove is different in form. 3 welding process is different. The strength after welding is different.4) Most of the lower pressure grades are smaller socket welds, and the higher pressure grades are often butt welds. Butt welds are 100% tested for flaw detection to ensure no leaks.