Discover how ASI Group Latam, together with ASI Group, overcame exceptional challenges at the Cheves Hydroelectric Plant (Peru) through the integration of innovative solutions and international collaboration, establishing themselves as leaders in underwater operations using ROVs (Remotely Operated Vehicles).
Bob Clarke, Vice President of Research and Development (R&D) at ASI Group, knew that the leakage in one of the tunnels at the Cheves Hydroelectric Plant, located in the province of Oyón, Peru, would be a significant challenge.
However, the combination of advanced technology, innovation, and dedication led the team to successfully overcome the challenge, setting a new standard for underwater operations at ASI Group Latam.
In this interview, we discuss the complexities, achievements, and lessons learned following the success of this operation.
Can you tell us about the project at Cheves Hydroelectric Plant? What was it about, what were the goals, and what did the work involve?
The project began with an inspection of the intake tunnel and the penstock of the plant (10 km in length). However, a 1.5 cm crack in the body of a relief valve located in the machine room (at the end of the tunnel), with water pressure of 60 bar (600 m of water column), caused a shift in the project scope.
Since there was no upstream valve to stop the flow and repair the crack, the technical teams at ASI Group Latam and ASI Group had to design a comprehensive solution to dismantle the damaged valve and inspect the pipe.
This situation required an integrated approach involving innovative proposals and collaboration with external companies in two major stages.
The first stage involved addressing the constant water flow caused by the valve crack. A custom-made sealing ring was designed by PLIDCO in the USA and installed around the valve body. Torque was applied, and the interior space was filled with high-density grease to provide a temporary solution. Simulations were conducted to assess the flow within the pipe, as the lack of an upstream valve posed a risk for inspection. To overcome this limitation, a blind flange was installed using a hot tapping procedure, which involves drilling into the pipe and introducing a line stop to block the flow. This strategy allowed the successful installation of the blind flange, creating the conditions needed for the second stage.
The second stage was conducted with the support of the Mohican ROV from Canada and a team of Chilean, Canadian, Colombian, and Peruvian personnel. The ROV completed two navigations inside the tunnel. The first navigation, using acoustic sensors (2D sonar, 3D profiler sonar, and scanner), captured images and data to determine the tunnel’s structural condition, completed successfully in 18 hours. The second navigation involved installing a 10” plug in the cooling pipe branch where the cracked valve was located, enabling the dismantling of the valve and installation of a new blind flange. This plug had to be installed 10 km from the tunnel entrance and transported by the ROV using an articulated arm, achieving success as planned.
Innovative Solutions in Underwater Operations
During the Cheves project, did ASI Group Latam face any particular challenges? If so, how did the team overcome these obstacles and find effective solutions?
The main challenge was integrating the expertise of five companies from five different countries, led by ASI Group Latam. A rigorous planning process ensured the project objectives were met on time.
Another significant challenge was inserting the plug in the pipe branch, as the ROV’s configuration limited lateral movements. With skilled pilots and a well-planned approach, the task was completed successfully.
Milestones and Achievements at Cheves
Was there a specific milestone in this project that you consider particularly significant or innovative for ASI Group Latam?
The installation of the plug stands out as a rare and challenging achievement. The cooling pipe’s location 10 km away required exceptional planning and execution, setting a benchmark for future projects.
A Look Toward the Future of Underwater Operations
Considering the experience and results at Cheves, what is your vision for similar future projects, and what lessons will be applied in future ASI Group Latam work?
At ASI Group Latam, in collaboration with ASI Group, we continuously seek innovative, comprehensive solutions to meet our clients’ needs, demonstrating our capabilities to go beyond traditional solutions.
