A pipeline operator required maintenance cleaning and corrosion mitigation across multiple transmission pipeline segments of 16-inch and 18-inch diameter.
While previous pigging campaigns had identified significant debris and contamination, the operator lacked clear visibility into the exact nature of the contaminants, their impact on pipeline integrity, and whether cleaning activities had effectively mitigated corrosion risks.
To resolve these operational uncertainties, the client required a comprehensive solution capable of:
• Assessing pipeline corrosion threats.
• Engineering an effective cleaning strategy.
• Executing the cleaning campaign.
• Verifying and documenting cleaning effectiveness.
• Providing technical guidance to support long-term integrity management.
Expro was selected to undertake the scope due to its ability to deliver a fully integrated pipeline health check and engineered cleaning solution combining laboratory analysis, chemical engineering, and field execution. Without this integrated solution, the pipeline would have remained exposed to ongoing corrosion risk and an uncertain integrity condition.
An 18-inch cleaning pig is removed after recovering substantial volumes of sludge and contaminants during Expro’s chemical pipeline cleaning campaign
TAILORED SOLUTION
Expro delivered a fully integrated pipeline integrity solution combining assessment, engineering, execution, and verification.
The programme began with Expro’s Pipeline Health Check, during which representative samples were collected and analysed to identify contaminants and integrity threats present within the system.
Laboratory analysis identified salt-rich iron sulphide and oxide deposits, chlorides, and scale fines, confirming liquid water intrusion and the presence of electrolyte reservoirs capable of driving corrosion.
Using this data, Expro engineered a tailored chemical cleaning programme specifically designed to remove the identified contaminants and address the underlying corrosion drivers.
Expro then executed a combined mechanical and chemical cleaning campaign.
Throughout the operation, samples were collected and analysed after each pig run to monitor contaminant removal, verify treatment effectiveness, and guide operational decisions.
This approach ensured the pipeline was cleaned effectively and efficiently while providing the operator with clear visibility into pipeline condition and integrity status.
Following the completion of the cleaning phase, Expro implemented corrosion inhibitor and biostatic treatments to protect the pipeline from corrosion.
Additionally, technical recommendations were provided to support long-term integrity management.
VALUE TO CLIENT
The project delivered tangible operational and financial value across several key areas:
• Extension of pipeline integrity and restoration of flow assurance: Contaminant levels were successfully reduced, removing corrosion drivers and restoring the internal surface condition of the pipeline.
• Improved cleaning efficiency and reduced campaign duration: The engineered cleaning approach accelerated cleaning performance compared to initial expectations, reducing operational time and associated costs.
• Verification of pipeline condition and cleaning effectiveness: The Pipeline Health Check and monitoring programme provided clear, documented confirmation of cleaning effectiveness and pipeline readiness for inspection.
• Enhanced integrity management capability: The programme provided the operator with an improved understanding of pipeline condition along with recommendations for ongoing monitoring and mitigation. Expro also identified upstream segments as candidates for similar programmes and potential sources of contamination.
• Establishment of long-term integrity monitoring strategy: The operator was advised to implement periodic Pipeline Health Check programmes to proactively manage pipeline integrity and prevent future issues.