In September 2026, the T-ALL Inspection in-line inspection team successfully completed the foam eddy current in-line inspection of a bimetallic clad gas gathering trunk line at an oilfield, completing the pipeline cleaning and inspection tasks as scheduled. Within 72 hours, the team completed four cleaning pig runs, one foam geometry inspection tool run, and one foam eddy current inspection tool run. The final inspection data were complete and valid, with good sensor coverage, marking a further breakthrough for T-ALL Inspection in the field of bimetallic clad pipe in-line inspection technology.

The inspected pipeline is one of the core gathering and transportation pipelines at the oilfield. Since being put into operation, it had never undergone systematic pipeline cleaning. With the continued development of the gas field, the amount of water entering the pipeline has increased significantly, resulting in substantial deviations between actual operating conditions and the original design conditions. The internal corrosion condition, liner integrity, and weld operating condition of the pipeline had remained largely unknown, while the risk of failure had gradually increased with service time. Pipeline safety risks had therefore become increasingly significant. As an important type of pipe used in oil and gas transportation, the long-term condition assessment and defect detection of bimetallic clad pipes have become essential to ensuring safe pipeline operation.

Faced with the inspection challenges associated with bimetallic clad pipes, and with the support of various departments at the oilfield, the company carried out multiple rounds of simulated pulling tests, inspection plan refinement, and detailed discussions of key technical issues to ensure the feasibility of the inspection plan and the reliability of the equipment. The team ultimately completed the inspection of the bimetallic clad pipeline successfully.

During the project, the team faced multiple practical challenges, with the key difficulties concentrated in three areas:

Extremely Tight Operation Window
The available on-site operation time for the project was extremely limited, and the overall schedule was significantly compressed. Pipeline cleaning and inspection operations had to be closely coordinated, placing very high demands on advance preparation, operational planning, and on-site execution efficiency.

Complex and Specialized Pipeline Conditions
The pipeline had not undergone cleaning for many years since commissioning, resulting in significant wax deposition and blockage inside the pipeline. The high resistance encountered by the cleaning pigs presented serious challenges to the passage of the inspection tools and the stability of data acquisition.

Special Structural Characteristics of Bimetallic Clad Pipes
The complex interface between the liner and the base pipe presents significant challenges for inspection. Due to the structural characteristics of the pipeline, previous inspection attempts had been unsuccessful because of issues such as liner bulging and deformation, leaving the inspection challenge unresolved for an extended period.

During project implementation, the team maintained efficient coordination with all parties on site, completing equipment preparation, inspection plan confirmation, and emergency response planning in advance, and systematically carried out the pipeline cleaning and inspection operations. During the operation, the inspection personnel overcame challenging site conditions, including rainfall, falling temperatures, and wax blockage inside the pipeline, and successfully completed all pipeline cleaning and inspection tasks within 72 hours.

The successful completion of this project enabled the effective acquisition of in-line inspection data for a complex bimetallic clad pipe using foam eddy current inspection technology, providing important technical support for subsequent pipeline defect identification, safety assessment, and operation and maintenance. At the same time, the project further demonstrated T-ALL Inspection’s technical capabilities and on-site service expertise in complex oil and gas pipeline inspection. Going forward, the company will carefully analyze and interpret the inspection data to provide more precise technical support for the safety assessment and subsequent operation and maintenance of bimetallic clad pipelines, striving to deliver a satisfactory result for the client.