There are various connection modes of stainless steel pipes. The common types of pipe fittings are compression type, compression type, union type,IlopangoStainless steel pipe drilling, push type, push thread type socket welding type, union flange connection, welding type and derivative series connection mode combining welding with traditional connection. These connection modes have different application ranges according to their principles, but most of them are easy to install, firm and reliable. The sealing ring or gasket materials used for connection are mostly silicone rubber,Ilopango304 stainless steel wire, nitrile rubber and EPDM that meet the requirements of national standards. L stainless steel pipe, s stainless steel pipe, L stainless steel pipe and other brand products are provided for a long time. The designated products are complete and the quality is guaranteed, which eliminates the need for useProper heat treatment process can prevent intergranular corrosion and obtain excellent corrosion resistance.Ilopango,The steel strip can be delivered without heat treatment under the condition that all properties meet the standard requirements. Ordinary drawing grade steel strip is allowed to be delivered without heat treatment.The corrosion resistance is the same, and the strength is better because the carbon content is relatively high.Levin,Stainless steel pipe packing bag is nothing more than the function of protecting the surface of stainless steel pipe, including the chemical fertilizer industry, has a great demand for stainless steel pipes. Stainless steel pipes are mainly used in this industry, including, , l, etc., material transmission pipes heat exchanger pipes, etc.Corrosion resistance of decorative stainless steel pipe the price of different series of stainless steel materials varies greatly. The corrosion resistance of more economical materials can not meet the higher application requirements, and the improvement of corrosion resistance of stainless steel materials by simple chemical passivation is limited. On the other hand, the traditional passivation treatment containing chromium salt has been gradually eliminated, and the passivation treatment of stainless steel has turned to the direction of environmental friendliness. Recently, citric acid passivation and silicon treatment on stainless steel surface have become a new research direction. The former has environmental protection characteristics because its passivation solution component does not contain chromium salt. The latter has found that silicon coupling agent is chemically adsorbed on the metal surface to form a protective silicon film with cross-linked network structure. The length of discoloration time of samples after different surface treatments was compared by blue dot method, the corrosion rate of samples after different surface treatments was distinguished by brine immersion test, and the salt spray resistance of samples after different surface treatments was distinguished by neutral salt spray test, The differences of pitting corrosion resistance and resistance to corrosive medium of samples after different surface treatment were compared by electrochemical test. The film thickness of silicon film was indirectly characterized by film weight test, and scanning electron microscope, energy spectrometer, X-ray diffraction X-ray photoelectron spectroscopy and total reflection Fourier transform infrared spectroscopy characterized the surface films of different surface treated samples, and analyzed the structural composition and corrosion resistance mechanism of different films. Professional stainless steel plate, stainless steel coil, stainless steel belt, stainless steel pipe, high price, service, on-site settlement, honest management! At present there are few studies on the combination of citric acid passivation and silicon treatment of stainless steel. Therefore, silicon treatment and the combination of citric acid passivation and acid silicon system treatment this paper studies the difference of corrosion resistance of martensitic stainless steel Cr chemical passivation, and discusses the corrosion resistance mechanism of different films on its surface, which can provide reference for the new direction of stainless steel surface treatment, It has certain practical guiding significance. The corrosion resistance and mechanism of chemical passivation, silicon treatment and composite treatment of martensitic stainless steel were studied in this paper. The comprehensive comparison of the research results shows that the corrosion resistance of stainless steel treated with different surface treatments is different. The corrosion resistance of the sample treated with silicon alone is better than that treated with traditional dichromate passivation. The corrosion resistance of the composite treated sample treated with citric acid passivation and acid silicon system is further enhanced than that treated with acid silicon system alone. The composite treatment of citric acid passivation and acid silicon system treatment has excellent corrosion resistance and environmental protection characteristics, and is expected to replace the traditional dichromate passivation treatment. According to the film weight test results, the surface silicon film weight of the composite treated sample after citric acid passivation and acid silicon system treatment is lower than that of the sample after acid silicon system treatment alone, indicating that the excellent corrosion resistance of the composite film not only depends on the surface silicon film, but also benefits from its double-layer film structure.

When using this process, the following key points should be paid attention to: during the welding process, the correct included angle between the welding handle, welding wire and weldment should be maintained. The ideal caster angle of the welding handle nozzle is & deg; & mdash; & deg;, and the included angle between the welding wire and the weldment surface is & deg; & mdash; & deg;; correct the molten pool temperature, change the included angle between the welding handle and weldment, change the welding speed, etc. to change the molten pool temperature, so as to ensure Beautiful weld formation (uniform width, no concave, convex and other defects) During operation, the current shall be slightly larger than that of solid core welding wire, and the welding handle shall be slightly adjusted to accelerate the separation of molten iron and molten flux coating, so as to facilitate the observation of molten pool and penetration; when filling the welding wire, it shall be sent to places of molten pool and pressed inward slightly to ensure penetration and prevent concave; during welding, and the welding wire shall always be ensured Under the protection of argon to prevent the end of the welding wire from being oxidized and affect the welding quality; pay attention to the welding quality of the arc and arc stop, and the spot weld shall be polished to & deg; the slope shall be gentle, and pay attention to the defects such as arc pit and shrinkage hole during arc stop.In addition, when selecting the reasonable thickness of the steel plate, its service time, quality and stiffness should be considered, and the strength requirements of the plate under pressure should be considered; Thermal conductivity; Distribution of pressure and format specification of pressing plate.Stress corrosion cracking (SCC) refers to the cracking caused by the combined action of stress corrosion stress (mainly tensile stress) and corrosion of austenitic stainless steel Austenitic stainless steel is prone to stress corrosion in corrosive media containing chloride ions. When the Ni content reaches % - %, it is a long-term enterprise engaged in stainless steel plate, stainless steel coil, stainless steel belt and stainless steel pipe. Welcome to consult. The stress corrosion tendency of austenitic stainless steel is very large. Continue to increase the Ni content to ~ %, and the stress corrosion tendency gradually decreases until it disappears.Project scope,At low temperature, ferritic stainless steel pipe has low-temperature brittleness like carbon steel, ferritic or martensitic stainless steel produces low-temperature brittleness, while austenitic stainless steel or nickel base alloy does not show low-temperature brittleness. Sus (Cr) and SUS (cr) of ferritic stainless steel pipe It shows that the impact value decreases sharply at low temperature. Therefore, it is necessary to pay special attention when using at low temperature. As a way to improve the impact toughness of ferritic series stainless steel, high purification process can be considered. With the help of C and N level, the embrittlement temperature is in the range of - ℃ to - ℃Austenitic stainless steel. It contains more than % chromium, about % nickel and a small amount of molybdenum, titanium, nitrogen and other elements. Good comprehensive performance and resistance to corrosion of various media.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 surface Rockwell hardness tester shall be used to test HRT or hrn hardness. For stainless steel pipes with inner diameter less than mm and greater 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.

Application fields: chemical industry, construction industry.Packaging strategy,Austenitic stainless steel is generally used for manufacturing and manufacturing chemical equipment components, low-temperature equipment components in refrigeration industry and can be used as stainless steel spring and clock spring after deformation strengthening.Stainless steel pipes are divided into hot rolled, hot drawn and cold drawn (rolled) stainless steel pipes according to the connection and rolling process. According to the difference of stainless steel microstructure, martensitic stainless steel pipes, austenitic stainless steel pipes, austenitic ferritic stainless steel pipes, etc.Assembly: the sealing ring shall be correctly installed in the U-groove of the pipe fitting, put the pipe into the socket of the pipe fitting and wait for crimping.Ilopango,Stress corrosion cracking (SCC) refers to the cracking caused by the combined action of stress corrosion stress (mainly tensile stress) and corrosion of austenitic stainless steel Austenitic stainless steel is prone to stress corrosion in corrosive media containing chloride ions. When the Ni content reaches % - %, it is a long-term enterprise engaged in stainless steel plate,Ilopango22 stainless steel, stainless steel coil, stainless steel belt and stainless steel pipe. Welcome to consult. The stress corrosion tendency of austenitic stainless steel is very large. Continue to increase the Ni content to ~ %, Rockwell and Vickers hardness indexes.