40-inch Natural Gas Pipeline Repair

Carbon Fiber Repair of 40-inch Natural Gas Pipeline

Background:

A 48-inch diameter natural gas pipeline, owned and operated by BOTAS, required reinforcement following a routine inspection. This pipeline, which had been operational for 20 years, displayed signs of wall thinning and degradation despite the use of cathodic protection. Maintaining uninterrupted service was critical during the repair, as the Maximum Allowable Operating Pressure (MAOP) of 75 bar (1,087 psi) needed to be sustained.

Problem:

Long-term exposure to operational pressures had led to pipe wall thinning, creating the need for an immediate and effective reinforcement solution. BOTAS required a repair method that would not only restore the pipeline's structural integrity but also maintain its operational safety and compliance with industry standards. Specifically, the carbon fiber repair solution needed to meet:

• ASTM G14 Impact Testing** – to simulate and withstand field damage.
• ASTM G62 Holiday Detection** – to confirm penetration resilience post-impact.
• ASTM G8 Cathodic Disbondment Testing** – to ensure compatibility with the existing cathodic protection system.

‍Solution:

HJ3’s CarbonSeal™ Repair System was selected as the optimal solution for its ability to meet all regulatory and operational requirements. Installation involved a certified installer who prepared the pipe by first setting up a trench box for safe access. They then removed the existing protective jacket to expose the steel surface in need of repair. After an abrasive blast to ensure optimal adhesion, the CarbonSeal™ system was applied and cured while the pipeline remained active.

CarbonSeal™ successfully strengthened the pipe to restore it to its original MAOP in accordance with ASME PCC-2 and ISO 24817 standards. This provided BOTAS with a cost-effective, durable, and compliant solution, designed for a 20-year lifespan.

Results:

• Restoration of Integrity: The pipeline was restored to safely operate at its original pressure level.
• 20-Year Repair Life: CarbonSeal™ ensures extended service life, mitigating future risks of wall loss.
• Continuous Service: The repair was completed without disrupting gas supply, preserving operational continuity.

HJ3’s CarbonSeal™ proved to be a robust solution, offering BOTAS both immediate reinforcement and long-term reliability to keep their pipeline safe and efficient.

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