Argon shall conform to the rules of national specifications and argon with purity of % shall be selected. If the content of impurities is too high, the maintenance effect of argon will be weakened and the weld quality will be indirectly affected.Good ductility, used for forming products. It can also be machined to harden rapidly. Good weldability. Wear resistance and fatigue strength are better than stainless steel.Portland,The existence of medium temperature brittle zone requires strict heat treatment and welding process system to avoid the appearance of harmful phase and damage the performance.Some reasons for product composition ratio: in order to reduce the production cost,Portland2507 stainless steel strip, reduce the proportion content of some important elements such as chromium and nickel, 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.Pozuelo de Alarcon,The numbering rules adopt element symbols; Pinyin, open hearth steel: p; Boiling steel: F; Killed steel: B; Class a steel: a; T: special GCr: ball.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.Stainless steel has two classifications: one is divided into chromium stainless steel and chromium nickel stainless steel according to the characteristics of alloy elements; The other is divided into m stainless steel f stainless steel, a stainless steel and A-F duplex stainless steel according to the microstructure of steel in normalized state.

Section shape stainless steel pipe can be divided into round pipe and special-shaped pipe according to the section shape. Special shaped tubes include rectangular tubes, rhombic tubes, elliptical tubes, hexagonal tubes, octagonal tubes and various cross-section asymmetric tubes. Special shaped pipe is widely used in various structural parts tools and mechanical parts. Compared with circular pipe, special-shaped pipe generally has large moment of inertia and section modulus, and has large bending and torsion resistance, which can greatly reduce the structural weight and save steel.Martensitic precipitation hardening stainless steel.Deformation strengthening of austenitic stainless steel stainless steel has good cold deformation performance. It can be cold drawn into very thin steel wire and cold rolled into very thin steel strip or steel pipe. After a large amount of deformation, the strength of the steel is greatly improved, especially when rolling in the subzero temperature zone. The tensile strength can reach more than MPa. This is because in addition to the cold hardening effect, there are also superimposed Deformation induced M transition.Quality improvement, Cr Ni 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.When installing and welding the fixed port of stainless steel pipe, it is difficult to vent on the inner side, and some sides are easy to be blocked. In this case, water-soluble paper + blocking plate can be used for blocking. That is, the easy to vent and good side can be blocked with blocking plate the difficult to vent and bad blocking plate side can be blocked with water-soluble paper, and the weld on the outer side can be blocked with adhesive tape (see Table ) .Ferritic stainless steel the Cr content of ferritic stainless steel is generally % ~ %, and the carbon content is less than .%. Other alloying elements are sometimes added. The metallographic structure is mainly ferrite, and there is no & alpha during heating and cooling=& amp; amp; gt;& gamma; The transformation cannot be strengthened by heat treatment. Strong oxidation resistance. At the same time, it also has good hot workability and certain cold workability. Ferritic stainless steel is mainly used to make components with high corrosion resistance and low strength requirements. It is widely used in manufacturing equipment such as production, nitrogen fertilizer and chemical pipelines.

Refining and transportation industries are in great demand. Secondly, geological drilling, chemical industry, construction industry, machinery industry, boiler, medical equipment, furniture and bicycle manufacturing also need a large number of various steel pipes. With the development of new technologies such as atomic energy,PortlandStainless steel column pipe, rocket, missile and aerospace industry, stainless steel pipe plays an increasingly important role in national defense industry,. Raw material problem of stainless steel pipe. If the hardness is too low, it is not easy to polish (BQ is not good). If the hardness is too low, orange peel is easy to appear on the surface during deep drawing, which affects BQ performance. BQ with high hardness is relatively good.According to different metallographic structure of stainless steel, it is divided into semi Ferritic and semi martensitic stainless steel pipe, martensitic stainless steel pipe, austenitic ferritic stainless steel pipe, etc.This material without titanium and niobium has an inherent tendency of intergranular corrosion. Intergranular corrosion can be reduced by adding titanium and niobium and stabilizing treatment. It is a kind of high alloy steel that can corrode in air or chemical corrosive medium. Stainless steel has beautiful surface and good corrosion resistance. It does not have to undergo surface treatment such as color plating to play a role of rust freePortland,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.The product quality advantages of continuous casting billet of stainless steel pipe fittings are mainly reflected in that the non grinding rate of the outer surface of the billet except the head and tail section has reached more than %, and the total surface grinding yield has reached %. In order to achieve this goal, it is necessary to refine the molten steel, achieve low oxygen and sulfur content, do a good job in the metallurgy of the ladle and tundish, accurately determine the molten steel temperature, Further reduce the inclusion content.Rheological and thermal changes in the quenching process of decorative stainless steel pipe the cooling characteristics of submerged quenching of stainless steel plate are numerically simulated by using the Euler multi fluid model in AVL fire software, and the numerical results are compared with the experimental results. In the research, the quenching medium is water. The mass, momentum and energy equations of gas-liquid two-phase of quenching medium and the quenching heat conduction equation of stainless steel workpiece are solved by numerical simulation. Based on the principle of equal heat flux between quenching medium and workpiece, the temperature field of quenching medium and workpiece is solved by coupling. The comparison between the numerical simulation and experimental results of decorative stainless steel pipe shows that the numerical simulation results of workpiece temperature are in good agreement with the experimental data. The model can reliably simulate the quenching process of workpiece, and can be extended to the multiphase flow simulation in complex system to guide the actual production. The single pass thermal simulation compression experiment of Cr super martensitic stainless steel was carried out by Gleeble thermal simulation tester to study the thermal deformation behavior at ~ ℃ and strain rate of . ~ s-,Portland63 stainless steel pipe, and the microstructure evolution law of grains under different conditions was analyzed; Based on Sellars hyperbolic sinusoidal model, the flow stress constitutive equation of Cr super martensitic stainless steel was constructed. The results show that the peak stress decreases with the increase of deformation temperature and the decrease of strain rate; With the increase of deformation temperature, the grain grows and coarsens gradually. With the increase of strain rate, the dynamic recrystallized grains are obviously refined. The thermal deformation activation energy Q = . JMOL of decorative stainless steel pipe is calculated, and the expression of Zener Hollomon parameter is obtained. Different feedstocks were prepared by mixing crmnmon nickel free austenitic stainless steel powder prepared by aerosol and wax based binder. The effects of binder ratio and powder loading on the rheological properties of feed were studied by rh high pressure capillary rheometer. Non Newtonian index n, viscous flow activation energy E and comprehensive rheological factor alpha are calculated by second order model regression analysis; STV. The results show that the prepared feeds are pseudoplastic fluid. The binder system was composed of % microcrystalline wax (MW), % high density polyethylene (HDPE), % ethylene vinyl acetate copolymer (EVA) and % stearic acid (SA). The powder loading was vol%. The feed had good comprehensive rheological properties. In order to study the cementitious properties of stainless steel AOD slag, stainless steel AOD slag was used to replace some cement, and its effects on the working properties and mechanical properties of cement mortar were studied. The results show that using stainless steel AOD slag to replace cement from ~ %, with the increase of the content of stainless steel AOD slag, the water consumption of standard consistency of cement first decreases and then increases. When the content is %, the strength of cement mortar decreases in turn, indicating that the cementitious activity of stainless steel AOD slag is small.