Successfully tackling a multidiameter inline inspection through a wye bend

?l 342 Growth Avenue provides reliable in-line inspection solutions to multiple operators within the region, with focus on collaboration and seamless adaptability to overcome technical challenges in multiple scopes of the pigging industry. The company continues to push for excellence within the technology and service sector with thorough research and development to complete project requirements.

The existing partnership between Growth Avenue and Pipesurvey International has brought success in a recent 365-kilometer subsea pipeline in-line inspection (ILI) operation for Trans-Thai Malaysia (Malaysia) EVA offshore pipeline. The inspected pipeline spans 365km from TTMM Muda Riser Platform (MRP) to Terengganu Onshore Gas Terminal (TGAST) and includes a 30-degree 24 inch wye-piece at 63km downstream with a 24”/28” expander at 75km.

Multi-diameter pigging tools were designed specifically for this line in order to inspect through the wye section and its diameter change in the pipeline, as well as the respective 3D bends within the line. Since the inspection team had previously inspected a 24” x 32” line, a similar multidiameter cup design was used to accommodate for the 24”/28” expander. The main challenge for this in-line inspection was designing the tools to successfully run them through the wye section, maintaining pass-ability by ensuring the tool keeps sealing in the wye in order to prevent the tool from stalling through the expansion while also accommodating for the other 3D bends. A dual module design was used in order to provide sufficient thrust to pass through the wye, where sealing was maintained at the back module when the front module exited the wye section to allow more thrust from the product flow. Figure 1.0 illustrates the two-module MFL tool at the wye section of the pipeline, with the back module maintaining flow sealing as the front module exits the wye section and figure 1.1 shows the front module creating a flow seal as the back module is about to exit the wye section. This is possible through the designed length of the tools.

The technology used in this operation is highly versatile, allowing for flexible modifications for different lines.Our multidiameter pigging technology is adaptable to run in all flow mediums and can be used in other pipeline sizes-- with a proven track record of up to 34” NPS. Sensor pads for data capture are able to retract and expand mechanically to provide precise readings throughout the inspection during pipeline diameter transitions. All aspects of the pipeline were taken into consideration during the design phase to ensure maximum quality in in-line inspection as we carry this mindset every project we dive into.

Figure 1.0 multi-diameter MFL

Figure 1.1 multi-diameter MFL