NACE ECDA Meetingevents.nace.org/conferences/ecda2009/images_presentations/SNanney… · NACE ECDA Standard - Late 2002 ... 192.925 –Refers to NACE RP 0502 for ECDA. Casings and

NACE ECDA SeminarJ. W Marriott Hotel

Steve Nanney

Project Manager

PHMSA – Engineering and

Emergency Support Section

January 26, 2009

Presentation Outline

Recent Accident and Incident Statistics

Gas and Liquid IM Programs Progress

Casings and Assessments

Recent Accident and Incident Statistics

Recent Incident Statistics

43 42 40 38

0

20

40

60

80

100

Source: DOT/PHMSA Incident Data as of Jan. 5, 2009

Pipeline Incidents Involving Death or Major Injury

1986 - 2008 (projected)

Statistical trend line on incidents

PerformanceTargets


0

20

40

60

80

100

120

140

2002 2003 2004 2005 2006 2007 2008

Pipeline Incidents w/Corrosion as the Primary Cause (2002-2008)

Gas Distribution (2%)

Gas Transmission (25%)

Hazardous Liquid (73%)

Source: DOT/PHMSA Incident Data as of Jan. 5, 2009


2008 Gas Transmission Incident Data

Material /Const

16%

External

Corrosion

10%

Internal

Corrosion

3%

Outside Force

(TPD)

17%Unknown or

Other

15%

Natural Forces

14%

Equipment or

Operations

20%

Other O/S Force-

Car

5%


2008 Hazardous Liquid Incident Data

Corrosion

20%

Equipment

31%

Outside Force

(TPD)

6%

Incorrect

operations

9%

Material/Const

17%

Naural Forces

5%

Outside Forces

2%

Other

10%

Gas and Liquid IM Programs Progress

Integrity Management Programs

History of the Gas Pipeline Integrity

Industry - Regulator Technical Committee - 1999

ASME B31.8S Standard - Late 2001

NACE ECDA Standard - Late 2002

192 Subpart O - Effective 12/17/2004

NACE SCCDA Standard - Late 2004

NACE ICDA Standard - 2007

Highest 50% of Gas Pipelines Assessed by 12/17/2007

All Gas Pipelines to be Assessed by 12/17/2012


Where we are today

End of 2008, >98% of gas transmission operators

inspected by state or federal pipeline safety officials

July 2008, operators assessed >75% of HCAs (reporting deadline March 2009)

All Gas HCA mileage inspected by 12/17/12

Large Liquid Operator HCA mileage inspected by

3/31/2008

Small Liquid Operator HCA mileage inspected by

2/17/2009


Gas Transmission

PARAMETER 12/31/2007 6/30/2008 TOTALS as of 7/1/2008

Total HCA Miles 19,300 19,300 19,300

HCA Miles Inspected 15,057 1,766 16,823

Immediate Repairs Completed 777 256 1,033

Scheduled Repairs Completed 1,752 438 2,190

Total Miles Inspected 291,900 292,600

Total Miles Inspected 96,981 25,947 122,928

Liquid Transmission

PARAMETER 12/31/2007 TOTALS as of 1/1/2008

Total HCA Miles 72,626 72,626

HCA Miles Inspected 72,000 72,000

Immediate Repairs Completed 5,943 5,943

60-Day Repairs Completed 3,951 3,951

180-Day Repairs Completed 16,027 16,027

Total Miles Inspected 461,237 461,237 May have multiple inspections


Integrity Threats to Cased Line Pipe

External Corrosion

Failed end-seals traps moisture inside casings

Coating damage leads to corrosion

poor construction techniques

lack of centralizers

Direct “hard” contacts and electrolytic shorts (coupling) of

cathodic protection system leads to corrosion

Atmospheric Corrosion



Internal Corrosion

Casing generally a low point

under highways or rail crossings

could accumulate liquids

SCC

Same as other line pipe



Seam issues the same

Girth weld issues the same

Construction issues may be increased due to alignment

issues



How large a problem are cased crossings?

Per AGA and INGAA, ~10,000 cased crossings in HCAs

on gas transmission pipelines

At 100‟ per crossing, < 200 miles of ~19,000 miles of

HCA or ~1%

Over entire gas transmission pipeline system:

Expected mileage of cased crossings is 1 to 2%

But number of incidents are unknown

(PHMSA has not tracked this metric)


PHMSA Letter of October 25, 2007 (to AGA)

Recognized acceptable to classify casings as low risk pipe for assessments

Clarified HCA mileage could be reported as complete without casings

Highlighted development efforts for GWUT

Highlighted efforts to assist operators with „Other Technology‟ notifications

Recognized NACE clarification of ECDA application with properly supported engineering and implementation plans per 192.925(b)(1)(ii)


PHMSA Letter of April, 2008 (to AGA)

Agreed - nothing explicit in rule requiring use of Guided

Wave as an indirect inspection tool for assessing

casings

Highlighted rule did not allow risk assessment in lieu of

assessing pipe in an HCA

Highlighted PHMSA efforts for developing guided wave

technology

Suggested workshop for stakeholders as starting point

for determining a solution


Where are we now?

In July 2008 PHMSA held workshop for stakeholders

PHMSA reached out to Industry and Industry

Associations for specific proposals

PHMSA met with AGA to form Joint Technical

Committee (NAPSR, Operators, Service Providers, PHMSA)


Where are we now?

Committee to meet in February

PHMSA supplied AGA with several Key Documents:

Spreadsheet showing reduced assessments (increased time between assessments)

Method to put casings into regions

Thoughts on how filled casing may be considered not to

have external corrosion threat (but still could have internal and SCC threats)

Guidance on how to maximize time between assessments

of casings


Regulations Governing Casings

192.467 – Electrical Isolation

Under IM Rule, assessment limited to casings in an HCA

192.901 – Limits to Gas Transmission

192.919(b) – Align Assessment Methods with threats to

be assessed

192.921 – Requires one of four Assessment Methods

(PT, ILI, DA, Other Technology)

192.925 – Refers to NACE RP 0502 for ECDA


How does NACE RP 0502 handle casings?

Casing are listed in both Table 1 and Table 2

Casings in a separate region from uncased line pipe

Casing indirect inspection tools may need special engineering considerations

Other methods may be used for casing crossings as per section 3.3.2

Indirect inspection tools not listed in Appendix A must

have a procedure, be validated, be appropriate and

effective per 192.925(b)(1)(ii) and section 3.4.3.1 of

NACE RP0502


How does NACE RP 0502 Handle Casings?

Two Complementary Tools

Strengths of one must complement weaknesses of other

(Section 3.4.1.2)

Tools must be selected to reliably detect corrosion

activity and/or coating holidays (Section 3.4.1.1)

Must obtain readings along the entire length of pipe

(Sections 1.2.2.2; 4.2.1.1; 4.1.2 and 4.2.2)

Must align, compare, and classify indications from two

tools (Sections 4.1.2.2; 4.3.2)


PHMSA proposed guidance regarding casings

Proposed ideas

Where assessments have been completed and monitoring

of casings has been performed, reevaluate the need to re-

assess at 7-year interim period

Suggested a methodology to combine similar casings into

regions using NACE RP 0502 as basis

Suggested a methodology to remove threat of external

corrosion from properly filled casings


What are other areas that could be reviewed?

How to assess casing regions so each individual casing

may not have to be excavated and examined

The effect of filling casings on assessments and

corrosion risks

How to eliminate cased crossings from future pipelines

New R & D initiatives to find a technological solution


Performing ECDA over paved surfaces

NACE RP 0502 Tables 1 and 2 state requirements for

using indirect inspection tools over paved surfaces

Per Table 1, these locations may be a separate region

Per Table 2, special engineering considerations (such as

drilling bore holes in pavement) may be necessary to

obtain accurate readings


Performing ECDA Over Paved Surfaces

What are some methods of performing an accurate

ECDA assessment?

Where new pavement or areas without cracks, drill

pavement until soil is reached

Where acceptable readings can be obtained through

pavement, use of special tools may be needed (This is typically in moist or humid environments.)

PHMSA Workshops

PHMSA Planned Workshops for 2009

Internal Corrosion Workshop

March 26, 2009 in Atlanta in conjunction with NACE 2009

Construction Workshop

April 23, 2009 in Dallas – Ft. Worth

Anomaly Repair Workshop – 2nd Installment

Planned during the summer of 2009

Casing Assessment Technical Committee

Ongoing discussion via Joint Technical Committee

(NAPSR, AGA, INGAA, PHMSA), February 2009

Questions

Thank You