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Full Length
Research Paper
Characterization of X-120M
pipeline steel
Jai Dev Chandel, Nand Lal Singh
M S University of Baroda, Vadodara, India
*Corresponding author email:
jaidev.chandel@jindalsaw.com
Received 13 August, 2011; Accepted 08 December, 2011
The metallurgical science
has been used to develop new weldable high strength steel
plates having strength and toughness of API-5L, X-120M for
manufacturing line pipes for transportation of petroleum
products. A pan cake type microstructure design has been
used to ensure the strength level of X-120M and ductile
fracture behavior at temperature down to -20 ºC. Ultra
refined, lean micro-alloyed chemistry design and plate
rolling through TMCP (thermomechanical control processing)
in combination with AC (accelerated cooling) steel has been
produced of lower transformation microstructure in the steel
plates. The steel chemistry and TMCP and AC plate rolling
designed in such a way that the plate should be of lower
bainite and lower martensite to achieve the strength level
of X-120M line pipe. The provision was made in the chemistry
so to have minimum effect of welding heat input on the base
metal or so called heat affected zone (HAZ) in the submerged
arc welding of long seam weld of line pipe.
Keywords:
TMCP, AC, HAZ, pan cake Microstructure, line pipe, API-5L,
HSLA, lower transformation product.
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