Sulphide stress corrosion cracking of multiple welding repairs of girth welds in line pipe

2009 ◽  
Vol 44 (4) ◽  
pp. 289-296 ◽  
Author(s):  
O. E. Vega ◽  
A. Villagómez ◽  
J. M. Hallen ◽  
A. Contreras
Author(s):  
Toby Fore ◽  
Stefan Klein ◽  
Chris Yoxall ◽  
Stan Cone

Managing the threat of Stress Corrosion Cracking (SCC) in natural gas pipelines continues to be an area of focus for many operating companies with potentially susceptible pipelines. This paper describes the validation process of the high-resolution Electro-Magnetic Acoustical Transducer (EMAT) In-Line Inspection (ILI) technology for detection of SCC prior to scheduled pressure tests of inspected line pipe valve sections. The validation of the EMAT technology covered the application of high-resolution EMAT ILI and determining the Probability Of Detection (POD) and Identification (POI). The ILI verification process is in accordance to a API 1163 Level 3 validation. It is described in detail for 30″ and 36″ pipeline segments. Both segments are known to have an SCC history. Correlation of EMAT ILI calls to manual non-destructive measurements and destructively tested SCC samples lead to a comprehensive understanding of the capabilities of the EMAT technology and the associated process for managing the SCC threat. Based on the data gathered, the dimensional tool tolerances in terms of length and depth are derived.


Author(s):  
James E. Marr ◽  
Neil Bates ◽  
David Portelance ◽  
Scott Farthing

Since the early 20th century, researchers and engineers have been using soils information to address corrosion issues on buried metallic materials. While this area of research was quite active from the 1920’s to the 1950’s, soils related corrosion pipeline research was declining until the mid eighties. For the non-soil scientist this area is complex and disruptive since there is usually no easy equation or consistent answer from buried point to buried point. Historically, the pipeline industry has developed coating systems that effectively place a barrier between the soil environment and the pipe surface. Over time, these coatings can deteriorate to such a level that the environment can either migrate through the coating or come in direct contact with the pipe surface. The second level of protection used in the defense of the pipe from the environment is the cathodic protection (CP) system. These systems can also deteriorate, but they can be monitored through measurement techniques at a given interval. The CP system can provide an adequate level of protection, thus minimizing potential pipeline integrity threats such as external corrosion and stress corrosion cracking. This paper will present a historical overview of the use of soils and soil survey information and will provide an overview our experiences related to the use of data effecting external corrosion and stress corrosion cracking of line pipe steels.


CORROSION ◽  
1995 ◽  
Vol 51 (2) ◽  
pp. 91-96 ◽  
Author(s):  
A. K. Pilkey ◽  
S. B. Lambert ◽  
A. Plumtree

Sign in / Sign up

Export Citation Format

Share Document