Development Trend of Sour Resistant Linepipe Steel and its Sour Characteristics in Welded Joints

Kim, Young-Hune; Song, Woo-Hyun; Koh, Seong-Ung

doi:2014.32.5.450

JWJ > Volume 32(5); 2014 > Article

Special Issue

Journal of Welding and Joining 2014 October;32(5) :450-455.
Published online October 30, 2014.

doi:https://doi.org/10.5781/JWJ.2014.32.5.21

Development Trend of Sour Resistant Linepipe Steel and its Sour Characteristics in Welded Joints

Young-Hune Kim^*, Woo-Hyun Song^*, Seong-Ung Koh^**

^*Welding and Joining Research Group, POSCO Steel Solution Center, Pohang 790-704, Korea
^**POSCOA Project Team, POSCO Technical Research Laboratories, Pohang 790-704, Korea

Correspondence: Young-Hune Kim Email: gogman@posco.com
Published online October 30, 2014

ABSTRACT

Oil and gas fields were left unexploited which deemed too deep and sour. New developing markets are emerging in this part and pipe manufacturers need demanding requirements in the combination of sour service requirements with heavier wall thickness required to cope with increasing water depths. Whilst, the strength and fracture toughness needed to meet the strict requirements In order to deliver the optimum sour properties in the final pipe, attention needs to be paid to each stage throughout the process from steel making. The main key during steel making is strengthening, securing mechanical properties and suppression of center segregation by adding proper chemical elements and controlling water cooling and plate rolling. Additionally in welding, it is required to prevent HAZ softening by high heat input during welding of heavy thick pipes and hydrogen assisted cracking in high strength steels with hard phases. In this paper, we introduce markets of sour resistant linepipe steels and in response to this, have a look in the development trend of sour resistant linepipe steels and its sour characteristics in welded joints.

Keywords: Sour | Welded joints | Pipeline | API