New Wave Media

 

By modifying a Saab Seaeye Falcon ROV, ASI Marine was able to send the vehicle through a pipeline stretching over four kilometers under Gladstone Harbor, Queensland to Curtis Island. 

 

They also sent the same modified Falcon through five kilometers of feeder pipes in Lake Ontario.

 

Under Lake Ontario in Canada, the Falcon worked in the worst freezing conditions on record to run five kilometers down each of three separate 1.6 meter diameter pipes in a unique project to create the world’s largest cooling system.

 

This deep lake cooling system feeds the city of Toronto in summer with cold water to cool the city’s offices – as a sustainable alternative to air-conditioning - then sends the water onwards to top-up Toronto’s municipal water supply.    

 

Bob Clarke, ASI Marine’s senior operations manager, said they achieved this by modifying the power supply to the system so that the Falcon could operate over five kilometers of tether.

 

This was particularly important for the Australian project, as their client wanted just a single point of access to inspect the 4.3 kilometer pipeline. 

 

The inspection on the Santos Gladstone LNG Project was conducted with the Falcon to confirm the condition of the pipeline that was pushed through the utility tunnel. 

 

The utility tunnel had been bored to minimize environmental impact at the site and to provide a protected conduit through which to pass the pipeline and other utilities. 

 

This was the last segment of the pipeline that delivers liquefied natural gas (LNG) to the Santos LNG plant on Curtis Island. The ROV inspection was conducted to ensure the pipe’s integrity during and after the push.

 

The Falcon was fitted out with video plus profiling sonar with a BlueView imaging sonar and Mesotech scanning sonar as additional navigation aids.

 

Clarke said they chose the Falcon for its “moderate size, good thrust-to-weight ratio and telemetry capacity”. It is also capable of unlimited inspection durations, he added. 

 

The Falcon’s intelligent architecture means each device on the vehicle can have its own microprocessor for individual control and systems can be easily changed or added.

 

Although small enough to be easily manhandled, its intelligent control, combined with five-strong thruster power and precise maneuverability, allows it to operate sensors, tooling and complex systems typically found on much larger ROVs, its developer said.

 

As a module-focused concept, the Falcon generates automatic diagnostics on power-up to ensure each device is fully interfaced and working correctly.