Performance of a Low-Drag Seal Assembly for Pipeline Pigging and a Novel Corrosion Pit Cleaning Brush

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1 Fiberbuilt Manufacturing: Dan Fletcher, Ph.D., P.Eng. Michael Hooper, Vincent Foong, MIET, MCMI, FIDIAG.E Performance of a Low-Drag Seal Assembly for Pipeline Pigging

2 Introduction Low-Drag Seal Assembly Results of Testing Improved Pig Seal Performance Alternative to Urethane Extremely Flexible and Low-Drag Adaptable for Aggressive Environments Corrosion Pit Cleaning Brush Results of Testing Specifically Address Corrosion Pits Innovative Brush Design Improved Cleaning Performance Improved Mitigation Program

3 Low-Drag Seal Assembly Compressed Outside Pipeline Brushes = Support Diaphragm = Sealing Sliding on brushes Extreme Flexibility Handles upsets in pipe ID Reduced Drag Custom Diaphragm Material

4 Low-Drag Seal Assembly New Seals reduce Differential Pressure (DP) Pigging effects on upstream production can be reduced Alternative to Urethane Modular and easily adapted for aggressive environments Aromatics, Bitumen, H 2 S, CO 2, H 2, High Temperatures Wide Dual Diameter Capability 3-6 Dual Diameter available

5 Eliminate Surging Improve ILI Inspections Constant speed Eliminate speed excursions Insensitive to ID changes Improve Batching and Dewatering Reduced bypass due to consistent seal/wall contact Better Batch Inhibitor Coverage Consistent seal contact Less drag on wall = less wiping

6 Dry Pull Testing Pulled through various pipe transitions Line pipe wall thickness changes Pipe schedule changes Welds and dent features Electric winch and Data Acquisition Plotted drag values Compared to a 3-cup Urethane pig

7 Dry Pull Testing SCH 40 SCH inch OD 5 mm w.t. 3-Cup Pig 4.5 inch OD 5.9 mm w.t. 3-Cup Pig Weld Dent Fiberbuilt Seals Fiberbuilt Seals

8 Internal Pitting Corrosion Internal Corrosion cause of 51% [1] of upstream multiphase pipeline failures Corrosion Pitting is a major concern Under Deposit Corrosion (UDC) Microbe Induced Corrosion (MIC) Improving pig performance can improve entire mitigation program effectiveness [1] Alberta Energy Regulator (AER), Report 2013-B: Pipeline Performance in Alberta, , August 2013, Available December 2016 at:

9 Mitigating Pit Corrosion Pigging Programs Disrupt deposits Remove Deposits from pit Expose bare metal Pigging Improvements Clean to depths of pits Improve surfactant use Help get corrosion inhibitors to pit bottom

10 Previous Study [2] AITF PICOM Joint Industry Project Phase 1 Completed December 2014 Evaluation of Pig Design for Deposit Removal from Corrosion Pits Test Method and Apparatus 4 Inch Flow Loop (Water), simulated sludge Measure the sludge removed from pits Depth and Volume recorded [2] W. Mosher et. al., Method of Evaluating Cleaning Pig Design for the Removal of Deposits from Corrosion Pits, NACE NAWC February 2015

11 Background Study Results [3] Evaluation of commercially available pigs Brushes are essential to effective pit cleaning Brushes don t reach out to nominal size Best Cleaning Depth = 25% of Pit Diameter Multiple runs = no added cleaning benefit [3] W. Mosher, Evaluation of Pig Design for Deposit Removal from Corrosion Pits Phase 1: Crude Oil Systems and Water Systems, Alberta Innovates Technology Futures (InnoTech Alberta), December 2014

12 An Improved Pit Cleaning Pig Clear need to improve pit cleaning brushes Improve effective reach into pits Make multiple runs more effective Improve pigs and pigging programs Increase pig performance Develop pig that allows for multiple runs Pigging in aggressive applications

13 An Improved Pit Cleaning Pig Improved brush geometry Radial and Raked Brushes Increase brush oversize Brush spacing resists pack-off Performance tested in the 4 AITF Flow Loop

14 Cleaning Performance Deeper Cleaning Cleaning improves when the pig is run multiple times Pit Sizes: mm in 3/16 5/16 3/8 1/2" 3/4" in

15 Depth as a % of Pit Diameter Cleaning Depth > 38% of pit dia. 50% - 70% improvement over the best performing pigs from the previous study [3] More runs = better cleaning

16 Volume of Sludge Removed Large volume removed from pits More runs = larger volume removed

17 Clean 19mm (3/4 inch) Pit Concentric rings in false-color image indicate a smooth conical surface: the drill point at the bottom of the coupon

18 Conclusions Low-Drag Seal Assembly Alternative to Urethane Adaptable for aggressive environments Flexible and Low-Drag Insensitive to wall thickness changes Eliminates surging and speed excursions Potential to improve ILI runs Potential to improve batching Improves corrosion inhibitor application Wide multi-diameter capability Corrosion Pit Cleaning Brush Specifically address corrosion pits Novel design and construction Improved cleaning performance More runs = better pit cleaning