Inclination Profile OVERVIEW 100
1000
Elevation
80
500
Inclination (degrees)
-500
40
Moving South
Inclination -1000
20 -1500
Elevation (feet)
0
60
0 -2000 -20
-2500
Moving North -40 0
5
10
15
20
25
?
-3000
Distance (miles) Inclination Crossover 1 Producer 2
Critical Angle (S->N) degrees Crossover 2 Producer 3
Critical Angle (N->S) degrees Producer 1 Elevation
Direct Assessment External Corrosion • Internal Corrosion • Stress Corrosion Cracking DNV provides expertise in all areas and stages of direct assessment (DA). Leaders in DA
Expertise Where You Need It
DNV played leading roles in the development of DA processes. We provide renowned experts in all areas of DA including External Corrosion (EC), Internal Corrosion (IC) and Stress Corrosion Cracking (SCC). No other organization can credibly claim a proficiency in all three areas of DA.
DNV assists you in all stages of DA program implementation. We conduct the following services in accordance with NACE and ASME standards: • Pre-Assessment to determine which segments should be assessed, establish the feasibility of performing DA and collect data pertaining to the segment being assessed. • Indirect Inspections, which includes flow modeling to identify locations of potential liquid accumulation (IC), above ground surveys (EC) and SCC prioritization. • Indirect Inspection Surveys, which includes pipe location and depth surveys, electromagnetic surveys, direct current voltage gradient surveys, close-interval surveys and GPS stationing. • Direct Examination, which includes pipe and coating assessment, soil resistivity measurements, corrosion mapping and corrosion product and soil analysis. • Post Assessment, which includes remaining life calculations, defining of reassessment intervals and assessing the overall effectiveness of the DA process. • Summary Report that thoroughly documents and explains findings and recommendations.
Our expert staff led the development of DA in following areas: •
Led Interstate Natural Gas Association of America’s (INGAA) projects to develop ECDA and ICDA
•
Supported the Northeast Gas Association (NGA) in its industry-leading ECDA validation effort
•
Implemented the concepts previously developed by the Canadian Energy Pipeline Association (CEPA) into an SCCDA process for all pipelines
•
Chaired on the National Association of Corrosion Engineers (NACE) task groups to develop ECDA, ICDA and SCCDA standards
DNV Columbus 5777 Frantz Road Dublin, OH 43017 USA 614.761.1214 dnvcolumbus@dnv.com www.dnvcolumbus.com
DNV Houston 1400 Ravello Katy, TX 77449 USA 832.541.1084 Chris.Pollard@dnv.com
DNV Calgary 2340 Pegasus Way, NE, Suite 123 Calgary, AB T2E8M5 Canada 403.250.9041 dnvcalgary@dnv.com www.dnvcalgary.com