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VideoRay's representative in China is Beijing Ocean

Seeker, and they have developed a reputation for excel- lence in underwater inspections in challenging conditions, particularly with hydroelectric power stations. The com- pany received a call from a diving company working on the Manwan station a few days before the Chinese New

Year.The Manwan station is located on the Lancang river, 510 km from Kunming, the capital of Yunnan province.

This is the first such plant on the Lancang; construction occurred between 1986 and 1995. It has a capacity of 1.25 gigawatts, and produces 7.8 billion KWH per year.

The challenge was to determine how badly the trash racks were blocked. If too much material is caught in the racks, the result is lower water flow and reduced power production. There are five arc gates, and each has three bar-type trash racks. The deepest part of the inspection was at 60 meters. The inspection was begun at 2:00AM, and needed to be finished by daybreak. To do this inspec- tion with divers was extremely difficult due to the condi- tions - particularly the bitterly cold water. The diving company was hopeful that the VideoRay could do the job more rapidly, and produce good video of the conditions at the trash racks.

The VideoRay was launched from a moveable raft, and dove down to the trash racks rapidly. Video and stills were captured on

Beijing Ocean Seekers' mp4 digital capture technology, which clearly showed that the intakes were badly blocked by branches and garbage. The divers were amazed at the speed with which the VideoRay could swim around the trash racks and complete the inspection - just 20 minutes per gate. The entire inspection was completed by 4:30 a.m. Weighing eight pounds and starting at $5995,

VideoRays can be equipped with sonar, positioning sys- tems or other accessories, and are used for underwater sur- veys, offshore inspections, search and recovery, homeland defense, science, fish farming and a range of applications in underwater environments.

For more information, visit

VideoRay Performs in China

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