nuclear-news

The second cutting of the contaminated pipe was interrupted because the device was stuck again

June 11, 2022
On June 10, TEPCO resumed removal work of pipes contaminated with highly radioactive materials between Units 1 and 2 at the Fukushima Daiichi Nuclear Power Plant (Okuma and Futaba, Fukushima Prefecture) for the first time in 18 days and began cutting a second pipe, but the work was interrupted by a problem. The chain-shaped cutting tool became stuck in the pipe. TEPCO was forced to review its construction methods.
　According to TEPCO, around 3:00 p.m., a large crane began cutting a 7-meter-long pipe (approximately 30 cm in diameter), and an hour later, when 90% of one side had been cut, the cutting tool became lodged in the pipe. At around 7:50 p.m., the cutting device was forcibly lifted up by a crane and removed.
　A similar problem at the end of March occurred when 90% of one side of the pipe was cut. When work resumed two months later after considering measures to prevent the pipe from biting, the piping had been cut spontaneously, so the prepared measures could not be tested on site.
　The piping, 135 meters long in total, was used for venting the steam containing high concentrations of radioactive materials that had accumulated inside the reactor to prevent the containment vessel from rupturing at the time of the accident in March 2011. Since it will be an obstacle to future construction work, it will be removed in 26 sections.
　The work began at the end of February, but after a series of troubles, the first pipe (approximately 12 meters long) was successfully cut on May 23. The cut surface of this pipe was found to have a radiation dose of 3 sievert per hour, which is high enough to kill a person if exposed to radiation for several hours, and the work procedure was reviewed. （The work procedure had to be reviewed.)
https://www.tokyo-np.co.jp/article/182880?rct=national&fbclid=IwAR3CC_FMnl5E_ZOsrclfdytCnDchF9ufc95QXfwiw5HaLqzns4ev20UBtPI

June 13, 2022 - Posted by dunrenard | Fuk 2022 | Contaminated pipes, Fukushima Daiichi, Removal work