Search Results

Flange manufacturing process, including forging and casting two processes, the two of them in the end what is the difference? Different in craftsmanship Forging flange process: forging is the metal heated to soften the state, through the external force hit, the formation of the required shape. Casting Farah process is: casting is the metal melt after the liquid into the mold in advance to make it cooling forming, casting process industry called Fansha. Product quality is different Forging flange than the cast flange its strength is relatively high, the quality is better, the general low-quality pipe will be used to connect the casting flange, high-quality pipeline forging flange for the connection. Use the different range Forged flange quality is better, the use of high-quality pipeline, can play a sufficient performance, is used in low-quality pipeline is of no use. Casting flange can only be used in 16Kg, normally used in 10Kg or 6Kg of the pipeline. Temperature requirements In addition to pressure requirements, the temperature can not be too high or too low. There is no general specification, but the important pipeline is recommended to use forging flange, such as some high temperature difference or pipe vibration place, casting flange quality may cause broken, crack, leakage and so on. Casting blanks due to the advantages of small margin in some unimportant occasions can also be used. Forged flanges do not have these defects, high-quality pipe installation is very common. Source: China Flange Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Stainless steel elbows buried in the ground can reduce the area, basically from the climate and the season and other external factors, more importantly, can reduce the heat transfer in the heat loss and prevent the pipe and pipe stainless steel elbow heat deformation. In order to reduce the heat loss and prevent the deformation of the stainless steel elbow, pipe buried depth should be 1.2 meters or more. (Calculated from the top of the tube). Alpine areas buried depth should be properly deepened. At the same time, the pipeline should be avoided at the groundwater level below. The groundwater level is higher or difficult for other reasons difficult to dig deep, should try to take waterproof and then take the safety measures after the pipe, the conditions are not available, but also take a shallow digging deep, that is, ditch to dig above the groundwater level Ten centimeters, and then according to the provisions of casing, the formation of embankment. But this will be put into operation after the maintenance of a greater difficulty in order to prevent pipe and stainless steel elbow deformation, to ensure that the casing pressure, shallow digging deep section of the casing thickness should not be less than 1.5 meters. Drawing and analyzing the hydraulic gradient line will help to study the oil pipeline and stainless steel pipe work after a variety of processes and a variety of conditions under the characteristics. For example, the state of the study graph can be said that when the flow rate is working and the viscosity of the liquid becomes large, the pressure at the end point becomes smaller due to the increase in hydraulic gradient. We use the steady-state pressure distribution diagram to study the working conditions of the pump station in detail. When the pump station is operated by the “tank” process, the pressure diagram of each section is independent of the operation of the adjacent stainless steel pipe fittings. The pressure at the starting section is determined by the work of the pumping station, and the pressure at the end point is determined only by the level of the liquid in the tank. However, as we have learned about the pump’s characteristic curve, when the flow increases, the pressure generated by the pump is reduced, so the pressure of the pump will be lower than that of the original working unit, and the stiffness of the stainless steel pipe Will also increase. Pumps and piping characteristics are the methods of combining the characteristic curves, and these methods are used when adjusting. Stainless steel elbow to change the characteristics of the pipeline can be used throttling and reflow method. At the time of throttling, the pressure loss caused by the hydraulic resistance established by the throttling member in the liquid flow limits the pressure behind the throttling member. When changing the hydraulic resistance, the throttle increases the loss and reduces the resistance to reduce the loss. Since the throttle resistance is placed within the pipe and the stainless steel elbow and is always in the liquid flow, there is always a pressure loss, even when there is no need to limit the pressure. Therefore, in the use of throttling adjustment, in order to compensate for the loss of throttle devices, oil always have additional energy consumption, usually these losses are 10-15 kPa. That is, in the rated conditions, stainless steel elbow throttling device energy loss of less than 1%. Source: China Elbows Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

The flange of the casting is the first time in 1809 by the British Irish tjaart (Erchardt) proposed, until the early twentieth Century was gradually being used to promote the flange. In 30s, our country began to make use of the casting and so on flange tube, tube casting such as iron pipe, copper sleeve, cylinder liner, bimetal steel back copper sleeve and so on. In the heat resistant steel roller, some special steel seamless tube blank, paper machine drying drum and other aspects of production, flange casting method is also very effective. At present, the system has a standard flange highly mechanized and automatic casting machine, has built mechanized mass production workshop pipe flange. Almost all the cast alloy can be used for American Standard casting flange, flange castings minimum diameter up to 8 mm, the maximum diameter of up to 3m, casting the maximum length of up to 8m, the flange casting weight range for a few tens of thousands of cattle (oregano against a few kilograms to more than and 10 tons). Because of flange casting, liquid metal is in the case of rotating mold filling and solidification, so it has the characteristics of flange casting: liquid metal free surface can form a cylindrical hollow in the mold, so that they can be cast in the casting hollow without core can greatly simplify the production process of pipe sleeve. Casting, the casting process is greatly simplified, high productivity and low cost; because the standard flange force generated by the rotation of the liquid metal, can improve the ability of filling metal casting flange casting process, so some poor fluidity of alloy and thin-walled castings are available flange casting due to flange force; the role of improving the feeding conditions, gas and nonmetallic inclusions also easily discharged from the liquid metal, so the flange casting organization is compact, the shrinkage hole (porosity), gas The utility model has the advantages of few defects such as holes, inclusions, good mechanical properties, etc. the utility model can eliminate or greatly save the metal consumption of the gating system and the riser, and the metal utilization rate is high. Source: China Flange Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

The manufacturing method of large diameter flange is usually made of steel plate cutting, cold bending or rolling, and then it is machined by large vertical lathe. The standard size of large diameter and the size of the standard are in accordance with the standard specifications. In the process of making large diameter flange, the production equipment of steel plate cutting method is the most simple, the investment is small, and the material utilization ratio is low. It is also very simple for standard size setting. Cold bending method is the first blank forging billet, and then cold bending into the arc section, annealing stress after heat treatment, the whole circle in the vertical to the shape and size of the design process. In fact, the whole process is a cooling and bending process, but in this process need to pay attention to the temperature and the degree of bending. The material utilization ratio of the rolling process is high, and the subsequent machining allowance is smaller than that of the steel plate cutting, but it is restricted by the equipment. At present, the maximum diameter of flange manufactured by this method is only 4m. China Flange Manufacturer wilsonpipeline Pipe Fitting Division Exports Large Diameter Flanges or flow control of oil, gas, water, steam, acid liquid, etc. Source: China Flange Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Flange in the use of industrial structures, mainly to improve the role of the connection, and to keep the seal of the pipeline no leakage, but many of the national standard flange after the use of a period of time will appear their own corrosion aging, which lost the effect of sealing, It is very necessary to do a regular anti-corrosion test on the flange. Here we share the process of measuring the corrosion of the flange. First of all must be sure that the flange to its regular maintenance and testing, after corrosion, usually the performance of the flange wall thinning, the emergence of local pits and pits. For the American standard flange internal corrosion causes and methods need to follow a certain way and principle, can now use at home and abroad more extensive flange corrosion detection method is the leakage flux method and ultrasonic detection method. Ultrasonic ultrasonic wave detection method is the use of ultrasonic pulse reflection principle to measure the thickness of the wall after corrosion. The basic principle of the magnetic flux leakage method is based on the high permeability of the ferromagnetic material, the permeability of the flange corrosion defects is much smaller than the permeability of the flange, Magnetic field lines are mostly distributed through the steel pipe, when the magnetic field lines are evenly distributed; when the flange inside the defect, the magnetic field lines are bent, and a part of the magnetic field leakage out of the steel pipe surface. Detection of the magnetized flange surface to escape the leakage flux, you can determine whether the defect exists. In addition, the probe will detect the ultrasonic pulse to the inner wall of the flange, the probe will first receive the reflection pulse from the inner surface of the pipe wall, and then the ultrasonic probe will receive the reflection pulse from the outer surface of the pipe wall. The pulse and the inner surface reflect the pulse The distance between the rows reflects the thickness of the pipe wall. Elbow in the actual test need to follow the actual situation and instructions, according to the ultrasonic method to detect a good way to test. The use of ultrasonic testing also applies to other metal structural parts thickness measurement and metal properties. China Flange Manufacturer wilsonpipeline Pipe Fitting Division Exports Flanges or flow control of oil, gas, water, steam, acid liquid, etc. Source: China Flange Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Method of calculating the weight of steel pipe The following: (1): cold drawn seamless rectangular steel pipe calculation method: W (kg / m) = side length * 4 * thickness * 0.00785 The following are the same as the “ (2): the density of steel is 1.85kg / dm2, the weight per meter of steel is calculated as: W (kg / m) = 0.02466 * wall thickness * (outer diameter – wall thickness) The following are the same as the “ (3): stainless steel pipe per meter weight calculation formula: W (kg / m) = 0.02491 * wall thickness * (outer diameter – wall thickness) Source: China Steel Pipe Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

A, the related factors should be considered when choosing gasket to know: A. to seal of highly toxic chemicals, chooses gasket safety performance is stronger, so as to guarantee; For transporting flammable liquid pipeline system, the need to pay attention to the gasket on the flange of the highest working pressure and temperature to control within a certain range, try not to exceed this temperature value; B. should plasticity and good, can with the flange sealing surface perfect unifies in together, this is you like to see; C. product processing performance is very good, in the installation and compaction is becomes with ease, do not have any inconvenience factors of resistance; D. non-caking flange sealing surface, remove it really is easy. E. to has a tendency to stress corrosion cracking of some metal flange, guarantee the gasket material won’t pile up too much of a corrosive impurities, such as control the content of chlorine ion gasket in case of our chosen flange produce certain corrosion effect; F. can good compression and rebound resilience is a fundamental guarantee, can adapt to the temperature and pressure fluctuations, it is extremely crucial point; 2, selection or order gasket should master first close technical data should be included, the following contents: A. match the flange sealing surface type and size, as the saying goes “suitable”; that is the reason why B. the size of the flange and gasket nominal diameter range value; C. the flange and gasket nominal pressure to know related information; D. leave medium temperature control is the most key; E. the medium of the keep properties to grasp clearly. China Gasket Manufacturer wilsonpipeline Pipe Fitting Division Exports Gaskets or flow control of oil, gas, water, steam, acid liquid, etc. Source: China Gasket Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

The impurities, salts, gases and microorganisms in the industrial cooling water will cause corrosion to the tube plate and weld. Then the main factors affecting the corrosion of the tube plate: (1) the composition and concentration of the medium: the influence of the concentration is different, for example, in hydrochloric acid, the greater the concentration, the more serious the corrosion. The corrosion of carbon steel and stainless steel in the sulfuric acid with the concentration of about 50% is the most serious, but when the concentration is increased to more than 60%, the corrosion decreases sharply; (2) impurities: harmful impurities, such as chloride, sulfide, cyanide, ammonia, etc., which can cause serious corrosion of the tube plate in some cases; (3) temperature: corrosion is a chemical reaction, the temperature is increased by 10 degrees C, corrosion rate increased by about 1~3 times, but there are exceptions; (4) pH value: the smaller the general pH value, the greater the corrosion of the tube plate; Source: China Tube Plate Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Tubular heat exchanger in production, tube plate and tube welding by manual arc welding, weld shape in the presence of different degrees of defects, such as depression, porosity, slag, weld seam stress distribution is not uniform. This means that we need to do some testing work in the production process. In the detection process of tube plate, the main indexes are holes, diameter tolerances, roughness of hole, burr, slotting position and so on, for the double sheet detection process, pay more attention to the hole, two hole tube plate matching degree is very important. General CNC drilling can be guaranteed. Relative to the thick plate, more than 300mm of the hole, the verticality of the hole is very important, these large diameter thick plate, the need for more sophisticated tools and equipment, special processing center in Longmen will be more and more widely used. Source: China Tube Plate Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

In recent years, duplex stainless steel has not only been widely used in major oil companies, the main pipeline system development, and is the main material for offshore oil production and transportation. Standard duplex stainless steel in the sweet, wet, acid service environment performed well. While ordinary carbon steel due to high internal corrosion rate, although the use of preservatives can be used to prevent external corrosion, but can not effectively prevent internal corrosion. Not only that, at 50 ℃ above the ambient temperature, but also may lead to stress corrosion cracking (SCC), so duplex stainless steel also gradually replaced the 300 series stainless steel. With the increase in the concentration of H2S in the transport of oil and gas, along with the gas temperature, pressure and pipe temperature increases, super duplex stainless steel began to use for piping systems, valves, heat exchangers, pressure vessel oil and gas equipment. When the oil industry gradually turned to high temperature, high pressure engineering, super duplex stainless steel will be more used. The general pipeline treatment system, will use 200 ~ 1 000 t super duplex stainless steel. In addition, the super duplex stainless steel can also be used for low pressure conveying system, submarine conveying pipeline. However, due to the higher price of duplex stainless steel, the promotion of its products affected. The advantages of duplex stainless steel are the following: · Yield strength is greater than the general austenitic stainless steel l times, and a good shape plastic toughness, the same design stress can reduce the wall thickness of 30% to 50%; · Excellent resistance to stress corrosion, in the chloride ion environment, it can solve the salient stainless steel difficult to solve the outstanding problem; The most commonly used 2205 duplex stainless steel corrosion resistance is better than 316L austenitic stainless steel, super duplex stainless steel in acetic acid, formic acid and other media can replace high alloy austenitic stainless steel; · Good resistance to localized corrosion, wear corrosion and corrosion fatigue resistance. Better than the alloy content of austenitic stainless steel; * Linear expansion is low, close to carbon steel, suitable for connection or composite with carbon steel. The typical duplex stainless steel is 2205 (22Cr-5Ni-3Mo) and 2507 (25Cr-7Ni-4Mo) type, the most widely used 2205, the oil and gas industry has been laying the length of oil and gas pipeline has more than 850 km, of which about 400 km belong to offshore oil field, the vast majority of 2205. Ferritic – austenitic duplex stainless steel (DSS) has a high strength and good resistance to chloride localized corrosion and stress corrosion. However, it should be noted that duplex stainless steel in the acidic environment, there are still some restrictions. Because the experimental study shows that it is more sensitive to the SSCC, the actual use should pay attention to the environment pH and stress levels. Source: China Duplex Stainless Steel Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Large diameter flange is a kind of flange, in the machinery industry, chemical industry, wind power industry, sewage treatment industry in the general use and promotion, users get the praise and favor, large diameter flange widely used. Production process is pided into rolling and forging, large can only be rolled. Material for the carbon steel, stainless steel and alloy steel. The inspection of the internal quality of the large-diameter flanges is to check the intrinsic quality of the large-diameter flanges, which is the quality condition that can not be found by the appearance quality check. It contains both internal defects for checking the large-diameter flanges and the mechanical properties of the check- Performance, while the important parts, key parts or large large diameter flanges should also be chemical composition analysis. As the large diameter flange made of parts, the use of the process of its force, the degree of importance, working conditions are different, the materials used and metallurgical processes are different, so different parts according to the above situation and in accordance with the requirements of the department will be large Caliber flange separation category, different departments, different standards for large diameter flange classification is different. Mass inspection of large diameter flanges: For internal defects we will check through the low magnification check, fracture check, high-speed inspection method to test whether the large diameter flange, such as internal cracks, shrinkage, loose, coarse, white, dendritic crystal, streamline does not meet the shape, Flow line disorder, through flow, coarse crystal ring, oxide film, stratification, overheating, burned tissue and other defects. For the mechanical properties is to check the normal temperature tensile strength, plasticity, toughness, hardness, fatigue strength, high temperature instantaneous fracture strength, high temperature lasting strength, sustained plasticity and high temperature creep strength. Large diameter flange is a precision casting method to produce flange, the kind of casting more common sand casting organization is much thinner, improve the quality of many, less prone to tissue loose, stomata, trachoma and other issues. Source: China Flange Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Stainless steel refers to the resistance of air, steam, water and other corrosive medium and weak acid, alkali, salt and other corrosive medium corrosion of steel, also known as stainless acid resistant steel. In practical applications, the corrosion resistance of steel is often referred to as corrosion resistant stainless steel, and the chemical resistance of the medium corrosion of steel called acid resistant steel. Due to the difference in chemical composition of the two, the former is not necessarily resistant to chemical medium corrosion, while the latter are generally non rust. The corrosion resistance of stainless steel depends on the alloy elements contained in the steel. The basic elements of stainless steel, nickel, molybdenum, titanium, niobium, copper, nitrogen, etc., in order to meet the needs of various applications of stainless steel structure and performance requirements. Stainless steel is easy to chloride corrosion, because chromium nickel chloride is collocated elements, elements will be collocated to form stainless steel corrosion exchange assimilation. Stainless steel pipe rust, may have the following reasons: 1, the use of chloride ions in the environment There is a wide range of chloride ions, such as salt / sweat / sea / sea breeze / soil, etc.. Stainless steel pipe in the presence of chloride ion environment, corrosion quickly, even more than ordinary low carbon steel. Therefore, the use of stainless steel pipe has the requirements of the environment, but also the need for regular cleaning, remove dust, clean and dry. This will give him a “improper use” The United States is an example: an enterprise solution with a container containing a chlorine ion of the oak, the container has been used for nearly 100 years, the 90s plan of last century replacement, due to insufficient material using modern oak, leakage due to corrosion of stainless steel container for 16 days after the replacement. 2, no solid solution treatment The alloying elements did not dissolve into the matrix, resulting in low alloy content and poor corrosion resistance. 3, inherent intergranular corrosion This kind of material without titanium and niobium has the tendency of intergranular corrosion. The addition of titanium and niobium can be reduced to intergranular corrosion. From the point of view of metallography, a thin chromium film is formed on the surface of the stainless steel tube containing chromium, which is separated from the oxygen in the steel from corrosion. In order to maintain the corrosion resistance of stainless steel pipe, steel must contain more than 12% chromium. Used for welding occasion, low carbon content makes precipitation near the weld heat affected zone of carbide minimized, and carbide precipitation may lead to intergranular corrosion of stainless steel pipe in some environments (weldingerosion). Source: China Stainless Steel Pipe Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)