Ensuring Reliable Gas Pipelines: Comprehensive Coating Failure Analysis

Project Background 

A prominent National Oil Company in the Middle East oversees extensive gas production fields in the United Arab Emirates. The gas is collected through a network of externally coated and cathodically protected underground flowlines that are located around Sabkha terrain, which is characterised by high salinity and periodic flooding. These conditions can impact pipeline coating failures by accelerating corrosion and compromising the integrity of the protective coatings.

To address observed coating failures within their pipeline system, the client asked Penspen to conduct a detailed Root Cause Analysis (RCA) to investigate and resolve these issues.

Study Objectives

To thoroughly investigate and resolve the coating failures, the study consisted of the following objectives:

• Root Cause Identification: Determine the primary causes of coating failures for 3LPP, 1LFBE, and 2LFBE coatings.
• Laboratory Testing: Conduct essential laboratory tests, including Hot Immersion Test, Differential Scanning Calorimetry (DSC), and Raman Spectroscopy, to confirm the root causes of the failures.
• Environmental Performance: Assess the performance of the coatings under current operating conditions, with particular focus on elevated temperatures and saltwater exposure in the Sabkha area.
• Disbonded Coating Detection: Recommend techniques for identifying locations of disbonded coatings in existing pipelines.
• Solidified Sand Impact: Examine the impact of solidified sand around the pipes on coating performance, particularly concerning temperature insulation.
• Specification Review and Gap Analysis: Review all relevant company specifications related to pipeline coating, cathodic protection, and pipeline construction to provide a gap analysis and recommend necessary revisions to mitigate failure causes.
• Cathodic Protection System Design: Review company specifications and design of the Cathodic Protection (CP) system, conducting a gap analysis to enhance system effectiveness.

Result

Penspen delivered a comprehensive suite of services to address coating failures in our client’s pipeline systems. We accurately identified the root causes of these failures in adherence to industry standard and pinpointed specification gaps contributing to the issues. Our immediate remedial actions addressed coating defects, cathodic protection, inspection programs, and operational considerations.

Our experts also conducted an in-depth analysis of the Sabkha terrain’s impact on pipeline failure and provided guidelines for construction in these areas. New temperature limitations for Glass Transition Temperature (Tg) were established to prevent coating failures during direct burial in Sabkha and recommendations for future coating qualifications were accurately provided to the client.

Value 

Our services to the client have significantly improved pipeline safety by reducing failures and minimising hazardous leaks, enhancing community safety and ensuring continuous energy resource delivery. Penspen’s commitment to delivery technical excellence ensures safe, reliable, and sustainable infrastructure, benefiting both the client and the communities they operate in.