您好,欢迎光临KCM Special Steel Co.,Ltd!
NEWS
CONTACT
Contacts: Bob Lee
Skype: bobo.lee2
Mobile No.&Whatsapp: +86-13758498349
address: Haining RD Yongzhong Street Longwan Area Wenzhou City Zhejiang Pr,China.
mailbox: bobo_lee2@hotmail.com,kcmsteel31803@gmail.com

NEWS

Current Position:Home > Industry news > Brief introduct

Brief introduction to the main points of the cold working process of duplex stainless steel tube

Release Date:2016-10-26

Core tip: for steel pipe, which is mainly used for stress corrosion, it is required to have solid solution and pickling state to avoid the mill. When the surface of the steel pipe is distributed with small cracks, folding and other defects need to be polished, the steel pipe after the grinding need to re - solid solution and pickling treatment to re - delivery. The tangential stress in the residual stress generated by the grinding is the principal stress of the SCC failure.

1, the yield strength of duplex stainless steel is twice higher than that of austenitic stainless steel, which should be smaller than the latter, the speed and feed amount must be chosen in the cold rolling. Cold drawn steel tube reduction rate should not be too large.

2, intermediate and finished steel softening heat treatment using continuous roller hearth type heating furnace (water cooling device with exit), prohibited the use of electric contact heating, which is not easy to control the temperature and the heating rate is very fast, easy temperature, ferrite phase number exceed the standard, especially in the rolling of thin walled tube, not once good control, easy to produce bamboo like uneven wall thickness, while the wall thickness is not mean little (less than 0.1mm). In electric contact heating, thin wall parts rapid warming, cause local overheating, the amount of ferrite increases greatly, and even the emergence of single-phase coarse grain ferrite, reduced corrosion resistance, then pickling, this part will produce local pickling, make steel scrap.

3, the solid solution treatment is very important, not only to eliminate the residual stress of the finished pipe cold processing, but also to ensure the proper proportion of the two phases as well as the surface quality of the finished product. Heat treatment need to pay attention to the uniformity of the material temperature and enough time to avoid the solid solution does not fully make the surface of the steel pipe residual stress is too high, resulting in some of the media lead to stress corrosion.

4, for the main resistance to stress corrosion of the steel pipe, the need for solid solution pickling state delivery, to avoid the grinding state of delivery. When the surface of the steel pipe is distributed with small cracks, folding and other defects need to be polished, the steel pipe after the grinding need to re - solid solution and pickling treatment to re - delivery. The tangential stress in the residual stress generated by the grinding is the principal stress of the SCC failure.


  • QQ咨询
  • 电话咨询