Fracture control plan

[09091960]

If one have to carryout fracture controll plan for 40 years old gas pipe line what methods use to address the issues related to interaction with weld heat effected zones, considerations for corroded pipe etc. For a newly fabricated pipes sample testing is a possibility where as old corroded pipes should have some procedures to incorperate these issues to the plan.Appreciate your feed back on this subject.

 

[BigInch]

Integrity monitoring plans usually don't get involved with sorting out the specifics of heat affected zones, but rather are determined based on the overall smart pig data reports showing general defect type, location, size, depth and remaining wall thickness, no matter what the initial cause of the defect might have been. All pipelines, old or new, should incorporate a GIS data base, including attributes for pipe, fittings, valves, pipe diameter, material, weld type and location when known, initial wall thickness, defect type and location, etc. and/or to leave spaces to hold such attribute data when it is to be determined at some time in the future.

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"The problem isn't finding the solution, its trying to get to the real question." BigInch

http://virtualpipeline.spaces.live.com/

 

[stanweld]

In addition to comments by Big Inch, you need to know the grade of pipe and the applied hoop stress as a percent of the SMYS. If you have access to MTRs look at the hoop stress versus the actual yield strength of the material. You also need to know the geology in which the pipeline traverses; landslides, earthquakes, fault crossings, railroad crossings, river crossings, road crossings and traffic volume, locations of potential frost heave, power lines. Is this gas cooled after compression or does it cool naturally (areas of potential stress corrsion cracking easpecially in alkaline soils)? You need to review the cathodic protection data over the years.

 

[BigInch]

Yes. The GIS data base would typically include all features that might impact the pipeline in one way or another, nearby houses, farm buildings, drainage features, water table, water wells, culverts, edges of pavements, drain tiles, as well as auxiliary equipment such as marker posts, test posts, ground beds, fencing, property lines, land ownership data, land use information, access routes, pretty much everything of interest really. Now that I have more time to think about it, ERSI has a few pages about pipeline GIS working with Arcinfo. Start with this one,

http://www.esri.com/library/brochures/pdfs/gis-for-petroleum.pdf

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"The problem isn't finding the solution, its trying to get to the real question." BigInch

http://virtualpipeline.spaces.live.com/

 

[SJones]

http://www.google.co.uk/search?hl=e...1&aql=&oq=pipeline+defect+assessment&gs_rfai=

Steve Jones
Materials & Corrosion Engineer

http://www.oilandgaspeople.com/cv/11499664

http://www.linkedin.com/pub/8/83b/b04

 

[09091960]

Many thanks for BigInch,Stanweld & Sjones for your inputs