New Toshiba robot for No.2 containment vessel

April 25, 2015

New robot tested for probing damaged reactor

http://www3.nhk.or.jp/nhkworld/english/news/nuclear.html

Apr. 25, 2015 - Updated 06:15 UTC+2

Engineers have tested a new robot designed to probe a damaged reactor at the Fukushima Daiichi nuclear plant.

Plant operator Tokyo Electric Power Company plans to use the device to view inside the containment vessel of the No. 2 reactor.

The robot is shaped like a scorpion and is equipped with front and rear cameras. Once inside the containment vessel, it is designed to raise its rear camera and capture images of its surroundings.

Engineers tested the robot on Friday at a factory in Yokohama City. The machine was inserted into a simulated section of the No. 2 reactor through a pipe 10 centimeters in diameter. It moved slowly on a rail-like structure to the center of a location under the reactor.

Tokyo Electric Power Company plans to implement the device at the No. 2 reactor as early as this summer.

TEPCO officials say radiation levels inside the No. 2 containment vessel reach 70 sieverts, which is higher than in the No. 1 unit.

They say they will implement the probe carefully by measuring radiation levels as they go. They say the new device can withstand radiation exposure of up to 1,000 sieverts.

Kazuo Sudo of the robot's maker Toshiba says the challenge is difficult as the situation inside the reactor is not known. He said engineers fear narrow parts of the rail and obstacles may hamper the robot's movement.

Sudo said that if the probe can find the location and condition of the molten fuel, it should help engineers figure out how to remove it.

A version of the robot sent into the No. 1 reactor was not able to see the condition of melted nuclear fuel, as it was unable to reach far enough under the reactor.