Specification of stainless steel square pipeAnalysis on the influence of international trade

announcer:hp717HP127443542 release time:2022-03-25 09:44:45

The requirements for weldability and weldability vary from product to product. A tableware usually does not need welding performance, and even includes some pot enterprises. However, most products require good welding performance of raw materials, such as class II tableware thermos cup, steel pipe, water heater, water dispenser, etc.

Corrosion resistance most stainless steel products require good corrosion resistance. Stainless steel pipe is similar to class I and II tableware, kitchen, water heater, water dispenser, etc. Some foreign businessmen also test the corrosion resistance of products: use NaCl aqueous solution to warm to boiling. After a period of time, the solution is to drain, wash and dry, and determine the weight loss to determine the degree of corrosion.

.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 87% hydroxide and 13% salt. The proportion of the two in the molten salt shall be strict, 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 8% (wt) It is treated in a salt bath furnace at 450 ~ 470 ℃ for 5 minutes for ferritic stainless steel and 30 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 (150 ~ 250 ℃, time 20 ~ 30min) ↠ 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, and then lower the parts basket into the water, Professional L stainless steel pipe,Thin wall seamless stainless steel pipe, s stainless steel pipe and 904L 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.

The surface quality, appearance and dimensional accuracy of cold rolled steel strip are better than those of hot rolled plate.

.Low temperature processing --- martensitic stainless steel is quenched from austenitizing temperature and then cooled to very low temperature to promote the quenching of martensite. It is suitable for stainless steel which is easy to produce retained austenite.

[hot rolled strip / sheet] has the advantages of low hardness, easy processing and good ductility.

Manufacturing process hot rolling (seamless steel pipe): round tube blank → Heating → Perforation & rarr; Three roll cross rolling, continuous rolling or → Off pipe & rarr; Sizing (or reducing) → Cooling → Straightening & rarr; Hydrostatic test (or flaw detection) → Mark & rarr; The raw material for warehousing and rolling seamless pipe is round pipe blank. The round pipe blank shall be cut and processed by cutting machine, and the blank with a growth of about 1m shall be brought to the furnace for heating. The billet is sent to the furnace for heating at a temperature of about 1200 degrees Celsius. The fuel is hydrogen or acetylene. The temperature in the furnace is the key problem. After the round tube billet is discharged from the furnace, it should be pierced through the pressure piercer. Generally, the more common piercer is the cone roll piercer. This piercer has high production efficiency and good product quality. It is specialized in stainless steel plate, stainless steel belt and stainless steel pipe, with high pressure resistance grade, good waterproof performance, fire and high temperature resistance, strong overload capacity, corrosion resistance, radiation protection, long service life, large perforation diameter expansion, and can wear a variety of steel grades. After perforation, the round tube blank is successively rolled by three roll cross rolling, continuous rolling or rolling. Take off the pipe after sizing. The conical drill bit of the sizing machine rotates into the steel embryo at high speed to form a steel pipe. The inner diameter of the steel pipe is determined by the outer diameter length of the sizing machine bit. After sizing, the steel pipe enters the cooling tower for water spray cooling. After cooling, the steel pipe will be straightened. After straightening, the steel pipe is sent to the metal flaw detector (or hydrostatic test) for internal flaw detection. If there are cracks, bubbles and other problems inside the steel pipe, they will be detected. Steel pipes should be strictly selected manually after quality inspection. After the steel pipe is inspected, the number, production batch number, etc. shall be sprayed with paint. And hoisted into the warehouse by crane.

Specification of stainless steel square pipeAnalysis on the influence of international trade

The specification and appearance quality shall comply with the provisions of gb14975-2002 stainless steel seamless steel pipe. The steel pipe is usually 5 ~ 10m long (indefinite length) hot rolled steel pipe, and the hot-rolled steel pipe is equal to or greater than 1m. The wall thickness of cold drawn (rolled) steel pipe is 0.5 ~ 0mm, 0 ~ 7m; the wall thickness is greater than 0mm, 5 ~ 8m.

Austenitic stainless steel austenitic stainless steel is developed to overcome the lack of corrosion resistance and brittleness of martensitic stainless steel. The basic composition is crl8% and Ni8%, which is referred to as 18-8 steel for short. Its characteristic is that the carbon content is less than 0.1%, and the single-phase austenite structure is obtained by the combination of Cr and Ni.

Usage: it is widely used in automobile industry, aviation industry and other departments.

ranking.The selection of stainless steel plate shall consider the operating conditions, such as manual operation or automatic operation, such as hardness and the quality requirements for materials, gloss, etc. Economic accounting should also be considered. Each time the steel plate is newly polished, it is required to produce a number of decorative plates with slow quality.

Stainless steel pipe national standard thickness in the stainless steel pipe industry, the steel that meets the national standard is generally called & ldquo; National Standard & rdquo; Inferior steel that does not meet national standards is called & ldquo; Winning the bid& ldquo; Non standard & rdquo; In practical application, the quality of national standard and non-standard is similar, but a thickness of non-standard is actually only 0.8mm or other thickness less than 1mm. Non-standard is basically equivalent to winning the bid. Standard index size (323mm) label number standard implementation standard gbt14976-2012 non-standard specific thickness ratio outer diameter steel pipes are produced according to the standard. 2 non-standard belongs to customized difference. Wood office says ha ha customized on demand. 3 thickness area: the difference between standard, thickened, stainless steel American Standard and national standard mainly lies in C content and P content; The C content and P content of Chinese standards are lower than those of American Standard ASTM A312@_@ The two important elements of material are chromium and nickel 15 9 large plants and 18 8 large plants of national standard and 18 8 small plants of American Standard 132@_ @ The national standard contains more than 17 chromium and the American Standard contains more than 18 chromium@_@ Stainless steel pipe is an American Standard, not in the national standard. The corresponding national standard is 06cr19ni10.

Physical properties the total heat transfer coefficient of metal depends not only on the thermal conductivity of metal, but also on other factors. In most cases the heat dissipation coefficient of film, rust scale and the surface condition of metal. Stainless steel can keep the surface clean, so its heat transfer is better than other metals with higher thermal conductivity. Liaocheng Suntory stainless steel provides the technical standard of stainless steel plate Stainless steel plate high-strength stainless steel plate with excellent corrosion resistance, bending workability, toughness of welding parts and stamping workability of welding parts. Specifically, Si, Mn, P, s, Al and Ni with an appropriate content of less than 0.02% of C,F53 stainless steel plate, less than 0.02% of N, more than 11% of Cr and less than 17% shall meet 12 & le; Cr Mo 5Si & le; 11 & le; Ni 30 (c n) 0.5 (Mn Cu) & le; Cr 0.5 (Ni Cu) 3Mo & Ge; 0, 0.006 & le; C, n & le; 0.030 stainless steel plate is heated to 850 ~ 1250 ℃, and then cooled at a cooling rate of more than 1 ℃ / S. in this way, it can become a high-strength stainless steel plate with martensite content of more than 12%, high strength of more than 730mpa, corrosion resistance and bending processability, and excellent toughness of welding heat affected zone. It can be significantly improved by reusing Mo, B, good wear resistance and poor corrosion resistance.

where.Low temperature processing --- martensitic stainless steel is quenched from austenitizing temperature and then cooled to very low temperature to promote the quenching of martensite. It is suitable for stainless steel which is easy to produce retained austenite.

Stainless steel pipe, which was consumed and used at the end of the 1990s, is a rebirth group emerging in today's pipe range. It has been widely used in the construction of water supply and direct drinking water pipelines. Stainless steel pipe is durable and has been recognized by the engineering community, and relevant parties are starting from reducing wall thickness and money, so as to facilitate further implementation. In order to promote stainless steel pipe, since the 1990s, China has started to reduce wall thickness and cost; High diameter to wall ratio and high precision & rdquo; The technical effect of stainless steel pipe makes the stainless steel pipe lose its application and expand quickly. There are various connection modes of stainless steel pipes. The rare types of pipe fittings include contraction type, compression type, union type, push type, push thread type, socket welding type, but most of them are convenient welding type and derivative series connection mode combining welding with traditional connection. These connection methods have different application ranges according to their principles firm and reliable. The sealing ring or gasket materials used for connection are mostly silicone rubber, nitrile rubber and EPDM that meet the requirements of national specifications, which eliminates the worries of users. In the construction of water supply pipe system, due to the glorious history of galvanized steel pipe, all kinds of new plastic pipes and composite pipes have been lost and developed rapidly, but they are far from fully meeting the needs of water supply pipe system and the national requirements for drinking water and related water quality. In direct drinking water, stainless steel pipe system is undoubtedly one of the best. At present, hotels and public places at the international level have been equipped or are equipped with direct drinking water pipelines. In many cases,Combined stainless steel plate water tank, stainless steel pipe has more advantages, especially the stainless steel pipe with wall thickness of only 0.6 ~ 2mm has the characteristics of safety, reliability, sanitation, environmental protection, economy and applicability in high-quality drinking water system, hot water system and water supply system that puts safety and sanitation first. It has been proved by engineering theories at home and abroad that it is not only one of the new, energy-saving and environmental protection pipes with good comprehensive function of water supply, but also a very competitive water supply pipe, which will play an unparalleled role in improving water quality and improving people's living standard.

  — General model; 188 stainless steel. The GB brand is 0Cr18Ni9.

.Steel strip, thin strip, roll strip, calendering strip and other strips can be cut with a thickness of 0.03 to 0mm (Note: stainless steel calendering strips of various thickness and width can be produced according to the needs of customers)

Organic substances (such as melons and vegetables, noodle soup, phlegm, etc.) adhered to the surface of stainless steel constitute organic acids in the presence of water and oxygen. For a long time, the corrosion of organic acids on the metal surface.

  ·Cargo box of ship or truck & middot; Food processing equipment standard ASTM / ASME......... A240 UNS S3 / s31803euronorm......... 4462 x2crnimon 23afnor.................. Z3 CrNi 205 azdin.............................. W. NR 4462 corrosion resistance uniform corrosion due to chromium content (22%)