When selecting stainless steel water supply pipe carefully observe whether the surface of the pipe is shiny， damaged and crushed， and pay attention to whether the incision is neat. If these phenomena occur， stainless steel pipe has a strong ability of atmospheric oxidation and is not easy to rust under normal circumstances， & ldquo; Stainless steel pipe & rdquo; Hence the name of. But what I want to tell you today is rust
d， showing a sharp drop in impact value. Therefore，stainless steel sheet it is necessary to pay special attention when using at low temperature. As a to improve the impact toughness of ferritic stainless steel，304 stainless steel seamless pipeStrengthen process and promote production high purification process can be considered. With the help of C and N level， it is possible to use it in freezing related engineering when the embrittlement temperature is improved in the range of - ℃ to - ℃. Recently， Nb LC) and susl have been applied to the shell of refrigeration appliances. Ferritic stainless steel has a body centered cubic structure. When the material properties become weaker， sharp cracks will expand rapidly and cause brittle failure. Austenitic stainless steel will not produce brittle failure because it has a face centered cubic structure. Austria has invested stainless steel SUSL (cr-ni-lc) and SUSL (cr-ni-mo-lc) show that they still have superior impact characteristics at low temperature. However， pay attention to the precipitation of ferrite or martensite due to processing， and the tendency of embrittlement caused by carbide or & sigma; equal heterogeneous precipitation due to sensitization.
cold rolled oriented silicon steel strip (sheet) represents: times of DQ + iron loss value (at the frequency of Hz， the magnetic induction peak with sinusoidal waveform is the unit weight iron loss value of T) + times of thickness value. Sometimes G is added after the iron loss value to indicate high magnetic induction. For example， dq represents cold-rolled oriented silicon steel strip (sheet) with iron loss value of and thickness of .mm. Now the new model is q.
ANevilleThe steady creep rate is usually used to evaluate the long-time creep performance of materials. For the application of long-life materials， the steady-state creep rate of stainless steel pipe under high temperature and stress is the key index of the material，stainless steel sheet and can be extrapolated. The following are the test results of stainless steel pipe under different test conditions. The results show that the steady-state creep rate of stainless steel pipe sample is in the order of magnitude after creep at ℃ (mpa ℃ (mpa) for h; when the temperature condition increases to ℃ (the stress decreases to MPa)， the creep performance of stainless steel pipe sample is good， and the steady-state creep rate is in the order of magnitude; when the temperature further increases to ℃ (the temperature creep rate of mpa stainless steel pipe sample increased to ℃ (mpa steady-state creep rate reaches the maximum value under several test conditions， and creep fracture occurs. See for the change of steady-state creep rate of stainless steel pipe sample under several conditions. When the temperature increases， the material maintains a low level of creep rate. Under ℃ MPa， s creep deformation rate does not increase， which shows that it is not very sensitive to the temperature and stress Compared with other common nuclear power structural materials it can be seen that the creep performance of several materials is better than that of ordinary materials under all test conditions. After hours of test， the total strain does not exceed .%. The curve is relatively stable with small fluctuation， indicating that the test data is stable and reliable. Stainless steel pipes have excellent corrosion resistance It is widely used in petrochemical industry， pipeline transportation and other working conditions with strong corrosive media. The main reason for the corrosion resistance of stainless steel pipes is the addition of a large number of elements CrNi，stainless steel sheet and Cr is the main element determining the corrosion resistance of stainless steel pipes. The electrode potential of stainless steel pipes increases with the increase of Cr content. However， stainless steel pipes In the subsequent heat treatment process，304 stainless steel seamless pipeStrengthen process and promote production Cr element will precipitate into the matrix in the form of carbide. On the one hand， the hardness of Cr carbide is larger than that of the matrix， and the service wear process can improve the wear resistance of stainless steel pipe. On the other hand， the precipitation of Cr containing carbide will lead to Cr Element dilution zone in some parts of the matrix， increase the number of batteries of the material， and make the electrode potential of stainless steel pipe Therefore in order to obtain good corrosion and wear resistance， the combination of mechanical properties and corrosion resistance of stainless steel pipe materials needs to be considered. At present， some scholars change the corrosion resistance of stainless steel pipes through heat treatment，tisco stainless steel sheet,taigang stainless steel sheet,stainless steel sheet,stainless steel coil,stainless steel strip,stainless steel tube-TISCO Stainless Steel Co.,Ltd and study the effects of austenitizing temperature and time， tempering temperature and time on stainless steel It is found that the austenitizing temperature can change the mechanical properties， but has little effect on the corrosion properties， while the tempering temperature has a great effect on the corrosion resistance of the material through the influence on the second phase. The corrosion wear resistance can be improved through appropriate austenitizing temperature and return fire temperature. Some scholars use surface treatment to improve the corrosion resistance of the material It is concluded that low-temperature nitriding forms a diffusion layer on the surface of the material， improves the wear resistance of the material， acts with Cr and chemically stable phase -fen to improve the corrosion resistance of the material.
OjThe corrosion resistance of duplex stainless steel， which is widely used in many media， is better than that of ordinary l austenitic stainless steel， while super duplex stainless steel has very high corrosion resistance. In some media such as acetic acid and formic acid， and the domestic steel inventory continued the growth trend at the end of the previous year. On March ， it reached a historical high of . million tons an increase of . million tons over the previous high， including . million tons of construction steel inventory， accounting for % of the total inventory. After that， with the increase of seasonal consumption， the inventory gradually fell back to . million tons on July . The oversupply in the market also pushed up the inventory of steel mills. In mid March， the steel inventory of key enterprises reached a historical record， reaching . million tons， and decreased to . million tons in late June， still an increase of % over the beginning. It specializes in selling stainless steel plate， stainless steel coil， stainless steel belt， stainless steel pipe and other products with complete types， selling well at home and abroad， and has a long service life! Products lead the industry in wire products. Welcome to inquire. An increase of % over the same period in .
There are ba face， b face， (white skin)， D face， (frosted)， HL (wire drawing)， K face and other surfaces with good quality and brightness.
qStainless steel and alloy tool steel (C content is expressed in thousandths)， such as thousandth of CrNi (i.e. .% C) stainless C & le; .%， such as CRNI ultra low carbon C & le; .%， such as crnimo.
XClassification and grading of standards - classification: national standard GB industry standard Yb local standard enterprise standard Q / cb- classification: product standard packaging standard basic standard - standard level (divided into three levels): y level: international advanced level I level: international general level H level: domestic advanced level - national standard stainless steel bar (level I) gb- stainless welding disc Park (level H)
VQuality documentsDuring butt backing， in order to prevent the back of the underlying weld bead from being oxidized， the back also needs to be protected by gas.
wRSeamless steel pipe belongs to the category with relatively high added value among steel pipe products， and the products involved in this case belong to the medium and high-end products of stainless steel pipe. According to incomplete statistics， in ， China exported about tons of stainless steel pipes to the EU， accounting for about % of the total exports of stainless steel pipes that year.
The rolling of cold drawn (rolled) seamless steel pipe is more complex than that of hot rolled (extruded seamless steel pipe). The first three steps of their production process are basically the same. The difference starts from the fourth step. After the round tube blank is emptied， it needs to be started and annealed. After annealing， pickling shall be carried out with special acid. After pickling， apply oil. Then it is followed by multi pass cold drawing (cold rolling) and special heat treatment. After heat treatment， it will be straightened.
Origin: domestic and imported (Sweden， Japan， Finland， South Korea， South Africa and Taiwan); classified according to the thickness of thin plate (.mm-mm)， medium plate (mm-mm)， thick plate (mm-mm) and extra thick plate according to the production heat
Excellent serviceuThe design shall be carried out according to the factors such as trench soil， groundwater， grooved section and load conditions. It is required to be firm and reliable， prevent collapse and support， and shall not hinder pipe laying and pipe stabilization.
OModel & mdash; Cheap model (British and American)， usually used as automobile exhaust pipe， is ferritic stainless steel (chromium steel).
Check whether the sealing ring of pipe fittings is complete and clean and whether the placement position is correct. If there is dirt， it must be cleaned up. If the sealing ring is damaged， weak corrosion resistance， % Cr， then slightly tighten the piece， and then rotate it for two circles until it is cut off. It must not be enough to allow personal strength to be in place at one time to lock the piece to cut off the pipe， otherwise the pipe end will be cut off， and the pipe fittings or rubber rings cannot be inserted; After the pipe above DN is cut， the internal and external burrs must be removed with a hand grinder， and an appropriate outer slope opening shall be opened at the same time to avoid damaging the sealing ring.
D-outer diameter (mm) as stainless steel pipe for reprocessing device， in order to reduce carbon content by vigorously welding chromium carbon compounds at affected parts， or silicon and phosphorus content in Nb steel. In addition， in order to improve the corrosion resistance of ULC steel， the steel industry with phosphorus content below .% is manufactured. Through repeated % boiling corrosion tests for times， it is concluded that if the corrosion degree of solid solution treated material is less than .mm/a， ℃ & times; The sensitized material for h has excellent corrosivity when the corrosion degree is less than .mm/a.