NACE International East Asia Pacific Rim Area Conference & Expo 2014 September 2 – 4, 2014 Nusa Dua Convention Center Nusa Dua, Bali, Indonesia Evaluation on the Cathodic Protection Inspection Methods for Underground Pipeline Paper No : P - 14 Ari Kurniawan – PT. KPM Oil and Gas – Aditya F. Arif– PT. Rekayasa Industri– Saturday, May 11, NACE EAP Conference & Expo

Outline  Background  Methods  Results and Discussion  Summary  References 5/11/ NACE EAP Conference & Expo2

Background  Cathodic Protection (CP) combined with coating are still the best method to prevent external corrosion  CP requires routine inspection as specify in Standard and Code  Some pipe owner does not perform inspection due to lack of knowledge or budget  Case Study for 16 inch aged gas pipeline 5/11/ NACE EAP Conference & Expo3

Background – Case Study  Pipeline  Length : 9 km  OD/WT: NPS 16 inch/9.53 mm  CP System: SACP every m  Coating: Coaltar Enamel  Age: > 10 years  Condition: Pararel with 2 foreign pipeline with ICCP  Current Inspection : p/s potential measurement only – pipeline was protected  Improvement method : CIPS, PCM, DCVG, ACVG 5/11/ NACE EAP Conference & Expo4

Background – Case Study P/S Potential Measurement last 3 month 5/11/ NACE EAP Conference & Expo5 TP No Chainage (m) Potensial Measurement vs CSE ( -mV) Remark Month 1Month 2Month Unprotected Protected Protected Protected Protected Protected Protected Protected Protected Protected Protected Protected Protected Less Protected Protected Protected Protected Less Protected Protected Less Protected Unprotected Protected Protected Protected Protected Less Protected

Methods  Close Interval Potential Survey (CIPS)  Pipeline Current Mapper (PCM)  Direct Current Voltage Gradient (DCVG)  BellHole/Direct Examination 5/11/ NACE EAP Conference & Expo6

Picture source : Peabody’s Control of Pipeline Corrosion, Methods CIPS (Close Interval Potential Survey )

P/s Potensial (-mV) mV Chainage (m) TP 1TP mV mV Methods CIPS (Close Interval Potential Survey )

 Continous potential measurement method  Measurement interval 1-3 meter  Use trailing wire and data logger  To check CP Protection level along pipeline Methods CIPS (Close Interval Potential Survey ) Picture source : CP2 – Cathodic Protection Technician Course Manual

 Measure Current Attenuation along pipeline  Indicate Pipe anomaly (Coating defect, metal contact, etc) Picture source : Pipeline Current Mapper User Guide by Radiodetection Methods PCM (Pipeline Current Mapper)

Normal Current DistributionAnomaly Current Distribution Picture source : Pipeline Current Mapper User Guide Methods PCM (Pipeline Current Mapper)

 Indicate Coating defect/anomaly by measure DC Voltage Gradient  Perform along pipeline  Not Indicate CP Protection Level  Could calculate qualitative Coating Defect (%IR) Picture source : Personal file Methods DCVG (Direct Current Voltage Gradient)

No % IRClassification 10-15%No repair required %Recommended to repair %Worthed to repair %Immediate repair 13 Picture source : Method Statement of DCVG by DCVG Technology Ltd Classification of Coating Defect Based on % IR Methods DCVG (Direct Current Voltage Gradient)

Methods ACVG (Alternate Current Voltage Gradient)  Indicate Coating defect/anomaly by measure AC Voltage Gradient  Performed along pipeline  Does not Indicate CP Protection Level  Could be used in concrete and asphalt Picture source : Pipeline Current Mapper User Guide

Methods ACVG (Alternate Current Voltage Gradient)

 Carried out at indicated location  Perform  visual observation  Potential measurement  Wall thickness measurement  CD repair Picture source : Personal file Methods Bellhole – Direct Examination

Results and Discussion Cathodic Protection Level 5/11/ NACE EAP Conference & Expo17 CIPS survey result at segment chainage 0 – 4500, first segment

Results and Discussion Cathodic Protection Level 5/11/ NACE EAP Conference & Expo18 CIPS survey result at segment chainage , second segment

Results and Discussion Cathodic Protection Level 5/11/ NACE EAP Conference & Expo19 CIPS survey result at segment chainage Current Pick Up Current Discharge

Results and Discussion Cathodic Protection Level 5/11/ NACE EAP Conference & Expo20  Protection level achieved only at test point  Indication of stray current at chainge and  Stray current come from other CP System (ICCP)

Results and Discussion Coating Integrity Survey 5/11/ NACE EAP Conference & Expo21 Result of PCM, ACVG and DCVG surveys segment KM , first segment

Results and Discussion Coating Integrity Survey 5/11/ NACE EAP Conference & Expo22 Result of PCM, ACVG and DCVG surveys segment KM , second segment

Results and Discussion Coating Integrity Survey 5/11/ NACE EAP Conference & Expo23 Result of PCM, ACVG and DCVG surveys segment KM , first segment CD No Chainage (m) Indirect Inspection Result Digging Validation Result PCM DCVG (%IR) ACVG (dB) CIPS Coating Condition Pipe Condition P/S Potensial (-mV) 1381Yes1934UYesCD FoundGC UYesCD FoundPT Yes--U Good ,93-PYesCD FoundGC P No U No Yes-30UYesCD FoundGC U No U No Yes-37UYesCD FoundGC ,39-U No Yes8,2840UYesCD FoundGC ,81-UYesCD FoundGC Yes1526UYesCD FoundPT642 Note U : Unprotected, P : Protected, GC : General Corrosion, PT : Pitting

Results and Discussion Coating Integrity Survey 5/11/ NACE EAP Conference & Expo24 CD found at chainage 4031CD found at chainage 8075

Results and Discussion Coating Integrity Survey 5/11/ NACE EAP Conference & Expo25 Pitting found at chainage 559

Summary  P/s potential measurement at certain sampling points is only able to give a figure on the CP level at the sampling points and hence inadequate for aged pipeline with possible interference with other CP system.  Combination of CIPS, PCM, DCVG and ACVG is an effective method to determine coating integrity and CP effectiveness.  It is highly recommended to apply a combination of CIPS, PCM, DCVG and ACVG surveys in a mandatory basis instead of supplementary. 5/11/ NACE EAP Conference & Expo26

References  A.W. Peabody, Ronald. L. Bianchetti, Peabody’s Control of Pipeline Corrosion, 2 nd ed. (Houston, TX: NACE, 2001)  W.Von. Beckmann, et al, Handbook of Cathodic Corrosion Protection Theory and Practies of Electrochemical Protection Processess, 3 rd ed. (Houston, TX: Gulf Professional Publishing, 1997)  NACE SP , “Control of External Corrosion on Underground or Submerged Metallic Piping System” (Houston, TX: NACE)  NACE International, CP2 – Cathodic Protection Technician Course Manual, (Houston, TX: NACE, 2008) : p 6:24  P. Nicholson, “External Corrosion Direct Assessment”, NACE CORCON INDIA 2004, (New Delhi, India: NACE India Section- Corrosion Society of India, December )  NACE SP , “External Corrosion Direct Assessment” ” (Houston, TX: NACE) 5/11/ NACE EAP Conference & Expo27

THANK YOU Acknowledgments PT. KPM Oil and Gas Board of Director 5/11/ NACE EAP Conference & Expo28