INTEGRITY MANAGEMENT FOR OLD PIPELINE SYSTEM

Transcription

1 International Gas Union - 23 rd World Gas Conference INTEGRITY MANAGEMENT FOR OLD PIPELINE SYSTEM Company: TRANSPORTADORA DE GAS DEL SUR Department: OPERATIONS Area: PIPELINE INTEGRITY Presenter: Daniel Falabella June Amsterdam

2 AMSTERDAN

3 Natural Gas in Figures Natural Gas is over 48% in the energy matrix 3.2 MM ton/year GLP production More than consumers MMm 3 Proven reserves 136 MMm3/ d production Argentina, a highly developed gas industry More than 1.4 MM CNG converted vehicles 60% of households Pipelines and networks km Delivered gas per year MMm3 Note: MM= 1 Million / Source: ADIGAS 2005

4 Characteristics of TGS system Largest Gas Transportation Company in Argentina Second LPG producer Approximately 60% of the Gas Transportation Market in Argentina (65.4 MM m3/day) 8,000 km of Gas Pipelines 30 Compressor Plants Installed capacity: 580,000 HP 8 Maintenance bases Average age of the Transportation System: 30 years Coating type: Asphalt: Tape: Three Layer Coating: 5,640 km 1,230 km 1,130 km

5 Classification of threats a) Time Dependent 1) External Corrosion 2) Internal Corrosion 3) Stress Corrosion Cracking b) Stable 4) Manufacturing Related Defect 5) Welding / Fabrication related 6) Equipment c) Time independent 7) Third Party / Mechanical Damage 8) Incorrect Operations 9) Weather Related and Outside Force

6 Cause of failure in buried pipelines 17% 7% 15% 11% Third Party Damage In Europe 50% 6 th Report of the European Gas Pipeline Incident Data Group(EGIG) December % 3% 6% TGS System Corrosion 57% 6% Corrosion SCC Third Party Materials Soil Movements

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8 What were our Problems? No Alternative Pipelines Contractual Requirements where Maximun Capacity is needed Very Long Pipeline System Poor Coating Condition Low Level of Cathodic Protection Great Number of Defect

9 In Line Inspection (ILI) in the TGS system (in km) 5,521 6, , /2007

10 Corrosion Defects - In Line Inspection 1994 Repairable Area Non Repairable Area ILI result of a section in our system

11 Works done in the System Pipe Replacement: 330 Km 40 NEUBA II 48 NEUBA I 242 SAN MARTIN NEUBA I Neuba II Sleeves: 935 San Martín 608 Recoating: 351 Km

12 Determination of Corrosion Growth Rates New corrosion sites d new = 10% Growth = 2% Repair Growth = 5% Growth = 1% d new =37% d new =7% Corrosion growth at existing sites New Data Old Data d old = 0% d old = 12% d old = 2% d old = 52% depthnew depth Growth = Time old Time (between Inspections): 5 years

13 Corrosion Growth Rates + Cathodic Potentials REPAIR PLAN 1.10 Critical area Repairable Defects Area Adequate cathodic potentials ERF 1.00 Non Repairable Potential (V) Defects Area Inadequate cathodic potentials Distance (km)

14 CP Units Evolution 263 Equipemets into operation G.del E. TGS Year Pipeline (km) Total CP Units Protected Pipeline (%) Km /CP Units , ,

15 SCC failures in NEUBA I Pipeline

16 Hydraulic Test Hydrostatic Test: 134 km 460 m of pipeline were replaced from service 23 SCC Colonies were detected 3 Cracks failed

17 MFL + TFI Tools Detector piston with cross-section magnetization Detector piston with longitudinal magnetization Magneto-cleaning piston Electronicprofiling piston Cleaning piston a) MFL tool b) TFI tool

18 SCC Susceptibility Model As first task were carried out a soil detail study Detailed (morphological, physical, and chemical) characterization of soils at the areas where SCC events were detected, and recognition of common patterns among the various areas under study. Enlargement: X 600

19 Data Integration Cathodic Protection Internal Inspection ILI Geographic Data (Rivers, soil, etc.) Cadastral Information (Densely Populated) Political Division (Populations, provinces, etc.) GPS data (x,y,z) Plants (compressor station, regulator, etc) Installations (stations, scrapper trap, derivations, etc.) Repairs (recoating, sleeve, increase cover, depth, replacement, etc.) GIS

20 Main Pipeline System Incident Summary 35 TGS beginning Old Trend 30 5 New Trend 25 4 Cumulative Failures Trends Cummulative Failures Failure year TGS Failures

21 Conclusions A 20-year old pipeline system may be reliably and safely operated at its maximum design pressure, provided there is a strategic Integrity Plan and if the required investments are made. To be able to plan the inspection and mitigation procedures, it is essential to identify threats to pipeline integrity. For the purpose of managing the variables that must be considered in order to develop an Integrity Plan efficiently, TGS implemented a thematic management of the information by means of a GIS platform

22 International Gas Union - 23 rd World Gas Conference INTEGRITY MANAGEMENT FOR OLD PIPELINE SYSTEM Company: TRANSPORTADORA DE GAS DEL SUR Department: OPERATIONS Area: PIPELINE INTEGRITY Presenter: Daniel Falabella June Amsterdam