Menu
Search
Filters
Close
Menu

Improved Girth Welding On Seamless Linepipe For High H2S Partial Pressure Condition

Picture for Improved Girth Welding On Seamless Linepipe For High H2S Partial Pressure Condition
Available for download

NACE MR0175 / ISO 15156 document part 2 provides material requirements for selecting cast irons and low-alloy steels for sour environments.1 Figure 1 is reproduced from this standard and describes different regions of environmental severity for Sulfide Stress Cracking (SSC): service in region 0 being the least susceptible to cracking, even for very sensitive materials, and region 3 being the worst.

Product Number: 51322-17710-SG
Author: Florian Thebault, Antoine Remy, Laurent Faivre, Sébastien Leconte
Publication Date: 2022
Industries: Coatings and Linings , Coatings
$0.00
$20.00
$20.00

O&G industry is more and more cautious about the risk of Sulfide Stress Cracking when low alloyed steels are in contact with aqueous environments saturated by high partial pressures of H2S. According to NACE MR0175 / ISO 15156 part 2, material tested in NACE TM0177 Solution A saturated by 1 bar H2S above 80% Actual Yield Strength is qualified for all regions of NACE environmental severity diagram. Basically, this lab test condition is considered severe enough for widening the admissible field exposure conditions up to 10 bar H2S partial pressure. However, recent works highlighted the existence of a threshold partial pressure of H2S below 10 bar for TMCP seam welded pipes. In the present work, similar situation has been observed for girth welds on X65 seamless pipes: acceptable welds based on hardness
data passed at 1 bar H2S NACE Solution A but failed in a fit-for-purpose condition of 6.8 bar H2S. Improved welding procedure has been defined for reaching the appropriate SSC resistance at this H2S partial pressure. It is recommended to evaluate the SSC resistance of girth welds at the field H2S partial pressure when superior to 1 bar.

O&G industry is more and more cautious about the risk of Sulfide Stress Cracking when low alloyed steels are in contact with aqueous environments saturated by high partial pressures of H2S. According to NACE MR0175 / ISO 15156 part 2, material tested in NACE TM0177 Solution A saturated by 1 bar H2S above 80% Actual Yield Strength is qualified for all regions of NACE environmental severity diagram. Basically, this lab test condition is considered severe enough for widening the admissible field exposure conditions up to 10 bar H2S partial pressure. However, recent works highlighted the existence of a threshold partial pressure of H2S below 10 bar for TMCP seam welded pipes. In the present work, similar situation has been observed for girth welds on X65 seamless pipes: acceptable welds based on hardness
data passed at 1 bar H2S NACE Solution A but failed in a fit-for-purpose condition of 6.8 bar H2S. Improved welding procedure has been defined for reaching the appropriate SSC resistance at this H2S partial pressure. It is recommended to evaluate the SSC resistance of girth welds at the field H2S partial pressure when superior to 1 bar.

Product tags
Also Purchased
Impact Of Material Properties Of Thick-Wall X65 TMCP Plate Steel For Sour Service
Available for download

Impact Of Material Properties Of Thick-Wall X65 TMCP Plate Steel For Sour Service

Product Number: 51322-17917-SG
Author: Thomas Haase, Christoph Bosch, Matthias Frommert, Markus Schürmann, Alexander Voelling, Sven Casper
Publication Date: 2022
$20.00

Low-alloy steel of API(1) 5L grade X65 is commonly used as line pipe material for sour service applications, where, due to stringent operation limits, resistivity to Hydrogen Induced Cracking (HIC), Sulfide Stress Cracking (SSC) and Stress-Oriented Hydrogen Induced Cracking (SOHIC) is required and tested before and after plate into pipe forming. Within recent years more challenging requirements have been introduced, including more severe corrosion test conditions, increased mechanical properties and extended limitations regarding hardness, to enable application to increasingly severe sour service conditions. For steel plants and plate manufacturers this entails the necessity to further improve the quality of their products together with separate improvements and modifications on the production plants and processes that have been implemented anyway.
Picture for Improved Cathodic Protection Current Distribution for Above Ground Storage Tank Bottoms Due to Low Resistivity Vapor Corrosion Inhibitor Use
Available for download

Improved Cathodic Protection Current Distribution for Above Ground Storage Tank Bottoms Due to Low Resistivity Vapor Corrosion Inhibitor Use

Product Number: 51322-17666-SG
Author: Sujay Math
Publication Date: 2022
$20.00

In this paper, the CP current distribution with changing resistivities and the area of influence required to meet effective CP criteria, is studied. The results indicate that the tank pad electrolyte resistivity plays a significant role in achieving uniform CP current distribution. The paper also explores the use of Vapor Corrosion Inhibitor (VCI) and its effect on electrolyte resistivity and the resulting CP current distribution.
Implication of Fractographic Analysis of the Crack in an Above Ground Pipeline – Potential Role of Hydrogen
Available for download

Implication Of Fractographic Analysis Of The In-Service Leak In An Above Ground Pipeline — Potential Role Of Hydrogen

Product Number: 51322-18022-SG
Author: Noelle Easter C. Co, Ming Gao, Ravi M. Krishnamurthy, Satya Kompally, Thomas Coates
Publication Date: 2022
$20.00

Fracture surface morphology is useful in determining the mechanisms involved in cracking. Features in the fracture surface of steel like micro-void coalescence or dimples are often related to ductile crack mode, while features like cleavage, and rock-candy showing grain boundary cracking are commonly related to brittle crack mode. Some fracture surface may have a predominant feature, while others may have presence of mixed features. Types of stress corrosion cracking (SCC) are commonly identified by the features present in the fracture surface. Features showing transgranular quasi-cleavage cracking are often related to near-neutral pH SCC, while features that show rock-candy intergranular cracking are often related to high-pH SCC [1].
Categories
Industry
Recently viewed
Popular tags
View all

Association for Materials Protection and Performance

© AMPP All Rights Reserved.
Membership Terms of Content Use
Contact Customer Support