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Chloride ions exist in the service environment. Chloride ions exist widely, such as salt, sweat, sea water, soil,Castries2520 stainless steel pipe, floating rust of iron foam and so on. Stainless steel corrodes rapidly in the presence of chloride ions, even more than ordinary low carbon steel. Therefore, there are requirements for the service environment of stainless steel, and it is necessary to remove dust frequently and keep it clean and dry. (in this way, we can give him a & ldquo; improper use & rdquo;) there is an example in the United States: an enterprise uses an oak container to contain a solution containing chloride ions. The container has been used for nearly years. The ninetieth generation of the last century plans to replace it. Because the oak material is not modern enough, the container leaks due to corrosion days after it is replaced with stainless steel.Model & mdash; Cheap model (British and American), usually used as automobile exhaust pipe, is ferritic stainless steel (chromium steel).Castries,Han Jianbiao, an analyst at Zoomlion steel, pointed out that since, China's steel pipe exports have been only or tons per month, of which seamless pipe exports are only about tons per month.Design and research of high precision stainless steel pipe stainless steel pipe has many advantages,CastriesDN80 stainless steel pipe, such as high strength, good corrosion resistance, strong impact resistance and so on, which makes it widely used in various fields of life. With the continuous improvement of automation, people have higher and higher requirements for the cutting quality of stainless steel pipe. At present, there are still many deficiencies in pipe cutting in China, which seriously restricts China's industrial development. Therefore, recently, the research on pipe cutting machine with high precision, high automation, high cutting quality and high cutting efficiency has become the research focus and difficulty of relevant disciplines, and it is also the inevitable trend of the further development of China's industry. Firstly, the intermittent cutting method of planetary bisymmetric eccentric installation can reduce the cutting deformation of stainless steel pipe and improve the cutting accuracy; Secondly, the tool of the intermittent stainless steel pipe cutting machine is eccentrically installed on the planetary gear to complete the rotation at the same time of revolution. Therefore, only one main motor can drive two tools to rotate. The mechanical structure reduces the use of the motor, improves the use efficiency of the motor and reduces the manufacturing cost of the equipment; Then, the main components of the intermittent pipe cutter are analyzed by using SolidWorks D solid software and ANSYS finite element analysis software. ANSYS software verifies the rationality of the structure and improves the service life of the pipe cutter. At present, there are still many deficiencies in pipe cutting in China, which seriously restricts China's industrial development. Therefore, recently, the research on pipe cutting machine with high precision, high automation, high cutting quality and high cutting efficiency has become the research focus and difficulty of relevant disciplines, and it is also the inevitable trend of the further development of China's industry. Firstly, the overall cutting scheme of the intermittent stainless steel pipe cutter is determined and the cutting force in the cutting process is calculated. Secondly, and the structure is designed. Then, the finite element analysis is carried out for the important parts of the intermittent stainless steel pipe cutter, the combination of theoretical analysis and computer simulation is used to verify the feasibility of the design, complete the tasks of scheme determination, theoretical analysis and structural design, and verify the rationality of the structure. This paper aims to design a pipe cutting machine with high automation, compact structure and high cutting precision, so as to improve the cutting quality of stainless steel pipe and bring more economic and social benefits to the enterprise. This paper comprehensively analyzes the research on stainless steel pipe cutting machines at home and abroad, draws lessons from the advanced structural design of relevant foreign pipe cutting machines, and makes a comparative analysis and Research on the characteristics of easy deformation and difficult cutting of stainless steel pipes. Taking the stainless steel pipe with diameter of mm ~ mm and wall thickness of mm ~ mm as the design object, and based on the structure of the existing planetary pipe cutting machine, A planetary double symmetrical eccentric installation intermittent cutting is proposed. The cutting can not only realize its own main motion and feed motion, but also reduce the deformation of stainless steel pipe in the cutting process. Professional L stainless steel pipe, s stainless steel pipe and L stainless steel pipe have large quantity, excellent quality and low price, fire resistance, water resistance high temperature resistance, strong and durable, safe and reliable, and improve the quality of cutting surface.Kanchanaburi,Austenitic stainless steel has good resistance to uniform corrosion, but there are still the following problems in local corrosion resistance: intergranular corrosion of austenitic stainless steel. Austenitic stainless steel will have intergranular corrosion when it is kept warm at ~ ℃ or cooled slowly. The higher the carbon content, the greater the tendency of intergranular corrosion. In addition, intergranular corrosion also occurs in the heat affected zone of the weldment. This is due to the precipitation of Cr rich CrC on the grain boundary. The chromium poor area is formed in the surrounding matrix, which is caused by corrosion of the primary cell. This intergranular corrosion phenomenon also exists in the ferritic stainless steel mentioned above.The best way to improve the quality of stainless steel pipe fittings is to change the process from ingot to billet. Due to the improvement of continuous casting process, it is widely used in the national economy. Because the steel pipe has a hollow section, it is suitable for gas and solid transmission pipelines; at the same time compared with the round steel of the same weight, the steel pipe has large section coefficient and high flexural and torsional strength, so it has also become an important material in various machinery and building structures. Stainless steel is used Under the condition of equal weight, the structure and components formed by pipe have a larger section modulus than solid parts. Therefore, stainless steel pipe itself is an economic section steel that saves metal. It is an important part of steel, especially in oil drilling, production and metallurgy

Adjust the ratio of austenite forming elements to ferrite forming elements in the steel to make it have austenite + ferrite dual phase structure, in which ferrite accounts for % - %. This dual phase structure is not easy to produce intergranular corrosion.In order to obtain seamless pipes with smaller size and better quality, cold rolling, cold drawing or a combination of both must be used. Cold rolling is usually carried out on a two high mill. The steel pipe is rolled in an annular pass composed of variable section circular groove and fixed conical plug. Cold drawing is usually carried out on a single chain or double chain cold drawing machine of . ~ t.Hardness test: annealed stainless steel pipes with inner diameter of more than mm and wall thickness of less than mm can be tested by w-b Vickers hardness tester, which is very fast and simple, and is suitable for rapid and nondestructive qualification test of stainless steel pipes. For stainless steel pipes with inner diameter of more than mm and wall thickness of more than mm, Rockwell hardness tester shall be used to test HRC hardness. Stainless steel pipes For stainless steel pipes with inner diameter greater than mm and wall thickness less than mm, the special Rockwell hardness tester for pipes shall be used to test hrt hardness. When the inner diameter of stainless steel pipes is greater than mm, the Rockwell or surface Rockwell hardness tester can also be used to test the hardness of pipes.Development Curriculum,The intergranular corrosion of austenitic stainless steel can be prevented by adding Ti, Nb and other elements that can form stable carbides (tic or NBC) and avoiding the precipitation of crc on the grain boundary.Some reasons for product composition ratio: in order to reduce the production cost, reduce the proportion content of some important elements such as chromium and nickel,Castries302 stainless steel strip, and increase the content of other elements such as carbon. This production phenomenon that the composition ratio is not strictly in accordance with the product model and product characteristics not only greatly reduces the product quality, for example, when the chromium content of stainless steel pipe is insufficient, it not only affects the production The corrosion resistance and formability of products have potential product quality and safety hazards when they are used in chemical equipment and production industries. At the same time, they also affect the appearance and oxidation resistance of products.Model & mdash; Add a small amount of sulfur and phosphorus to make it easier to cut.

When hoisting stainless steel pipes, public slings, such as hoisting belt and public collet number, shall be used. It is strictly prohibited to use steel wire rope to avoid scratching the surface; and when hoisting and placing, it shall prevent scratching caused by impact and collision. If there are surface scratches, electric arc traces and surface purification in the process of transportation, storage and processing, it must be completely cleaned, polished with an angle grinder, and then polished Polishing with optical sheet or metallographic sandpaper.OK or not?,There are mechanical chemical and electrochemical methods to remove the scale of stainless steel pipe. Due to the complexity of the composition of the scale of stainless steel pipe, it is not easy to remove the scale on the surface and make the surface highly clear and flat. Generally, the removal of the scale of stainless steel pipe should be carried out in two steps, the first step is pretreatment and the second step is ash removal.The surface of the steel strip in the state of supply shall be rough or bright.Stainless steel pipes can be divided into CR series ( Series), Cr Mn Ni series ( Series) and precipitation hardening series ( Series). Series & mdash; Cr Ni Mn austenitic stainless steel series & mdash; Cr Ni austenitic stainless steel.Castries,Various welding methods of combined welding stainless steel welded pipe have their own advantages and disadvantages. Combined welding methods include argon arc welding plus plasma welding, high-frequency welding plus plasma weldingTherefore, there are requirements for the service environment of stainless steel, and it is necessary to remove dust frequently and keep it clean and dry.The scale pretreatment of stainless steel pipe makes the scale loose, and then acid pickling is carried out for easy removal. The pretreatment can be divided into the following: alkaline salt melting treatment method. The alkaline melt contains % hydroxide and % salt. The proportion of the two in the molten salt shall be strict, so that the molten salt has strong oxidizing power, low melting point and small viscosity. Only the sodium halo shall be analyzed in the production process and the content shall not be less than % (wt) It is treated in a salt bath furnace at ~ ℃ for minutes for ferritic stainless steel and minutes for austenitic stainless steel. Similarly, iron oxides and spinels can also be oxidized by salt to become loose ferric oxide, which is easy to be removed during acid pickling. Due to the action of high temperature, some of the formed oxides peel off and sink to the furnace bottom in the form of sediment. Alkaline salt melting pretreatment Process flow: steam degreasing → preheating ( ~ ℃, time ~ min) ↠ molten salt treatment & rarr; water quenching & rarr; hot water washing. Molten salt treatment is not suitable for assemblies with weld gap or crimping. When the parts are taken out of the molten salt furnace, a stream of alkali and salt mist will be splashed during water quenching, so deep well anti splash water quenching tank shall be used during water quenching. During water quenching, firstly lift the parts basket into the tank, stop above the horizontal plane, close the tank cover, Professional L stainless steel pipe, s stainless steel pipe and L stainless steel pipe are stable safe, reliable and maintenance free. The technical level has reached the domestic level and the international advanced level of similar products until submerged.