Blog
We look forward to working with you,mutual benefit and win-win,create brilliant!
Let's help you
MoreLatest News
What problems should be paid attention to when the welded pipe unit produces oil casing?
Release time:
2018-12-06 11:46
The control methods of weld groove corrosion include: the use of thermal tension diameter reduction can reduce the sensitivity of groove corrosion; Reducing the S content in steel and controlling the precipitation of inclusions such as MnS and FeS along the weld area can also reduce the sensitivity of weld groove corrosion. In addition, reasonable addition of alloying elements can refine the grain size of the welding base metal and improve the groove corrosion in the weld area.
1. Groove corrosion of weld
The control methods of weld groove corrosion include: the use of thermal tension diameter reduction can reduce the sensitivity of groove corrosion; Reducing the S content in steel and controlling the precipitation of inclusions such as MnS and FeS along the weld area can also reduce the sensitivity of weld groove corrosion. In addition, reasonable addition of alloying elements can refine the grain size of the welding base metal and improve the groove corrosion in the weld area.
2. Gray spot of weld
Gray spot is a plane defect at the weld fusion line, and the fracture is generally gray flat spot, usually round, oval or long strip.
The gray spot has a great influence on the chemical composition, microstructure and stress distribution of the weld zone, and seriously affects the mechanical properties of the oil casing. The main factors of weld ash are the chemical composition of the welding base metal, welding temperature, welding speed, extrusion amount, opening angle, and the edge shape and surface quality of the strip before welding.
Strict control of strip steel edge quality and welding process is the main way to solve the weld gray spot, through the weld heat treatment and thermal tension reduction before the whole pipe body heating can reduce the welding oil casing weld gray spot trend.
3. Toughness
The welded pipe unit produces oil casing, because the weld toughness is affected by the toughness of the base metal, the chemical composition of the base metal and the welding process. When the content of C, S, P and Cr elements in the raw material strip steel decreases, the weld toughness can be improved. When the width of bright line, the included angle of streamline and the content of non-metallic inclusions in the welding process are controlled, the weld toughness can also be obviously improved. In addition, the welded pipe can improve the strength and toughness of the weld of the welded oil casing and other areas of the pipe body through controlled cooling after reducing by thermal tension.
Latest News
Contact Us
Tel :+86-514-87736047
Phone :+86-15062802588
E-mail : market@nanyangmill.com
Address : Yangshou industry park,Hanjiang District, Yangzhou City, Jiangsu Province, China
Business License
This website already supports IPV4 / IPV6 bidirectional access