{"id":800645,"date":"2026-10-12T23:02:11","date_gmt":"2026-10-12T23:02:11","guid":{"rendered":"https:\/\/www.newsbeep.com\/uk\/800645\/"},"modified":"2026-10-12T23:02:11","modified_gmt":"2026-10-12T23:02:11","slug":"a-1455-pound-slab-of-steel-more-than-7-8-inches-thick-was-cut-out-of-a-retired-french-reactors-pressure-tank-by-a-laser-on-a-remote-controlled-arm-in-a-few-hours-after-18-months-of-planning","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/uk\/800645\/","title":{"rendered":"A 1,455-pound slab of steel more than 7.8 inches thick was cut out of a retired French reactor\u2019s pressure tank by a laser on a remote-controlled arm in a few hours, after 18 months of planning, so engineers can see what four decades of heat did to its hottest weld"},"content":{"rendered":"<p>KeysQuestions4Vehicle1<\/p>\n<p>France just used a remote-controlled laser to carve a 1,455-pound chunk out of a retired nuclear reactor&#8217;s pressurizer \u2014 and the reason why reveals a high-stakes gamble playing out across the entire Western nuclear fleet.<\/p>\n<p>The cut targeted the single hottest weld on the tank, the spot that spent four decades under the most punishment, and what engineers find inside that steel could rewrite the timeline for dozens of reactors still running today.<\/p>\n<p>If those reactors get cleared to run past 60 years, it changes the entire energy equation \u2014 power prices, grid stability, and the nuclear renaissance everyone keeps talking about all hinge on answers hiding in that 7.8-inch slab.<\/p>\n<p>Ask The Box \u2192<\/p>\n<p>Considering the Accord?<\/p>\n<p>Accord vs rival?Best trimReal MPG<\/p>\n<p>AI-generated summary from reviews, comparisons and articles by AutoNotion<\/p>\n<p>I spent part of my weekend reading a nuclear plant\u2019s newsletter, which probably tells you all you need to know about my weekends.<\/p>\n<p>That they\u2019re awesome.<\/p>\n<p>But enough about me. The plant is Fessenheim, a retired one in eastern France, right by the German border. Its <a href=\"https:\/\/www.edf.fr\/sites\/groupe\/files\/2026-09\/Fessenheim-essentiel-1217-septembre-2026.pdf\" target=\"_blank\" rel=\"noopener nofollow\">September issue<\/a> reads a lot like a small-town paper, with a photo exhibit, a new communications chief, and an old fire pump the plant donated to a nearby village\u2019s fire station.<\/p>\n<p>Then you get to page 2. That\u2019s where EDF, the state-owned French utility that runs the plant, mentions that it recently had a piece of steel weighing about 1,455 pounds cut out of the pressurizer on one of the plant\u2019s two reactors. EDF wants to know what more than four decades on the job did to it.<\/p>\n<p>So why take a laser to a nuclear plant that\u2019s already shut down?<\/p>\n<p>Because it\u2019s shut down. EDF is studying whether its other reactors can keep running for more than 60 years, and you can\u2019t exactly carve a chunk out of a pressurizer that\u2019s still under pressure. The newsletter makes the same point a little more politely, explaining that a closed plant lets EDF analyze materials it can\u2019t access in a running one.<\/p>\n<p>So what\u2019s a pressurizer?<\/p>\n<p>Fessenheim\u2019s two reactors are 900-megawatt pressurized water reactors, the same basic type as most reactors operating in the US. The water that cools a reactor like that gets hundreds of degrees hotter than a pot of boiling water, and the only reason it doesn\u2019t turn to steam is pressure, lots of it. Your car\u2019s radiator cap pulls the same trick on a much smaller scale, since pressurized coolant can reach higher temperatures before it boils.<\/p>\n<p>The pressurizer\u2019s job is to keep that pressure where it should be. It uses electric heaters to raise the pressure and water sprays to lower it, and it\u2019s a separate tank from the reactor vessel, the big steel pot that holds the fuel. So nobody was cutting into the reactor itself. We\u2019ve covered the inside of one of these before, when a Swedish plant had to <a href=\"https:\/\/www.autonocion.com\/us\/93-ton-pressurizer-one-16-inch-hatch\/\" rel=\"nofollow noopener\" target=\"_blank\">fix 30 melted heaters through a single 16-inch hatch<\/a>.<\/p>\n<p>      Autonoci\u00f3n Newsletter<\/p>\n<p class=\"mn-nl__legal\">No spam. Unsubscribe anytime. <a href=\"https:\/\/www.autonocion.com\/us\/privacy-policy\/\" target=\"_blank\" rel=\"nofollow noopener\">Privacy policy (opens in new window)<\/a><\/p>\n<p>EDF\u2019s sample came from the bottom section of the pressurizer\u2019s shell, at a circular weld that runs hotter than anywhere else on the tank, according to <a href=\"https:\/\/www.onet.fr\/blog\/premiere-mondiale-onet-technologies-realise-un-prelevement-par-decoupe-laser-sur-un-pressuriseur-a-fessenheim\/\" target=\"_blank\" rel=\"noopener nofollow\">Onet Technologies<\/a>, the French contractor that did the cutting. Fessenheim\u2019s second reactor ran for more than four decades before it shut down for good in 2020. So that weld\u2019s had a long, hot career, and starting with the hardest-working part of the tank makes pretty good sense to me.<\/p>\n<p>Onet says the piece is made of steel and stainless steel, and it\u2019s a big one. It\u2019s just under 4 feet long and just under 2 feet wide, and it\u2019s more than 7.8 inches thick. Big pressure tanks like this are usually thick steel with a stainless lining on the inside, where the water touches, which would explain the mix. EDF calls the job a first for its nuclear fleet.<\/p>\n<p>So how do you cut steel that thick by remote control?<\/p>\n<p>The setup paired a high-power laser with a cutting head built for nuclear work, and the head rode on a robotic arm that operators ran remotely. A laser cutter basically melts a narrow line through the metal while a gas jet blows the molten material out of the way. The cut itself took a few hours, according to Onet. But, brace yourself\u2026 The prep took almost 18 months.<\/p>\n<p>That probably sounds lopsided, but I\u2019d argue it\u2019s the right way around. You only get one shot at a sample like this, and Onet says the cutting and extraction both took place in a particularly cramped space.<\/p>\n<p>The job wasn\u2019t only cutting, either. Onet\u2019s team also had to take the cover off the pressurizer\u2019s manway, a hatch big enough for a person to climb through, and then put it back on, as any decent mechanic would. Once the sample was cut free, it was pulled out, decontaminated, and packed up for shipping.<\/p>\n<p>Onet hasn\u2019t said how powerful its laser is, only that it\u2019s high-power. Neither company has said what day the cut happened, and EDF\u2019s September newsletter only calls it recent.<\/p>\n<p>The sample<\/p>\n<p>1,455 lb<\/p>\n<p>Steel and stainless steel, cut from the pressurizer of Fessenheim\u2019s second reactor.<\/p>\n<p>Size<\/p>\n<p>4 x 2 ft<\/p>\n<p>Just under 4 feet long and just under 2 feet wide, taken at the tank\u2019s hottest weld.<\/p>\n<p>Thickness<\/p>\n<p>7.8+ in<\/p>\n<p>Cut through in a few hours by a laser on a remote-controlled arm.<\/p>\n<p>Prep time<\/p>\n<p>18 months<\/p>\n<p>Almost a year and a half of planning and proving out the method before the cut.<\/p>\n<p>ACTIVE<\/p>\n<p>Sampling at Fessenheim<\/p>\n<p>Until 2034<\/p>\n<p>About 20 kinds of equipment and materials, from cable to concrete cores, scheduled around the teardown.<\/p>\n<p style=\"font-size: 12px; color: #94a3b8;\">Figures: EDF, Onet Technologies.<\/p>\n<p>EDF is sampling about 20 kinds of material at Fessenheim<\/p>\n<p>EDF runs all of this through a project it calls Dur\u00e9e de Fonctionnement, which translates to something like operating life, and it launched the project to address the technical side of running its plants for more than 60 years. Fessenheim\u2019s role is basically an organ donor.<\/p>\n<p>The pressurizer piece is one item on a long list. Anne-Fran\u00e7oise Cotte, one of the people running the project, told the newsletter that EDF is sampling about 20 types of equipment and materials at Fessenheim. That covers electrical connectors, several-yard-long cables, fire dampers (the flaps that seal off air ducts in a fire), cores drilled out of the concrete, and chunks of the casings from the big pumps that push water through the reactor. It even covers sand. EDF didn\u2019t say what it\u2019s hoping to learn from the sand, and frankly, I\u2019m curious.<\/p>\n<p>Once the samples are out, they go to a lab. EDF says it regularly passes the results on to the ASNR, France\u2019s nuclear safety regulator, and works them into its studies. It also fits the sampling in around the teardown so it slows the dismantling as little as possible. EDF hasn\u2019t said which lab is getting the pressurizer piece or when the results will be ready.<\/p>\n<p>And Fessenheim is definitely coming apart. On May 1, the French government signed the plant\u2019s dismantling decree, and crews have begun cutting away the piping and flooring installed around the steam generators in a reactor building. EDF says Fessenheim is the first plant built on the same reactor technology as the rest of France\u2019s working fleet to be taken apart. I\u2019d guess that\u2019s a big part of why its metal is so useful to EDF.<\/p>\n<p>Some American reactors are cleared to run for 80 years<\/p>\n<p>If you\u2019re reading this in the US, you\u2019ve got a stake in what that lab finds.<\/p>\n<p>The NRC has been approving licenses that let some American reactors run for 80 years, and Florida\u2019s St. Lucie plant <a href=\"https:\/\/www.autonocion.com\/us\/two-reactors-sea-turtles-canal-19987-times\/\" rel=\"nofollow noopener\" target=\"_blank\">got its pair in April<\/a>. Nobody\u2019s run a big commercial reactor that long yet, so metal that\u2019s actually aged on the job is pretty valuable evidence.<\/p>\n<p>Results from Fessenheim have already reached US regulators. At a technical meeting between the NRC and the US nuclear industry last year, <a href=\"https:\/\/www.nrc.gov\/docs\/ML2516\/ML25163A019.pdf\" target=\"_blank\" rel=\"noopener nofollow\">a presentation on cracking in reactor piping<\/a> passed along EDF\u2019s results from Fessenheim\u2019s other reactor. EDF had cut open eight welds in the pipe linking the reactor\u2019s pressurizer to the rest of its cooling loop, and found no cracks in any of them. My guess is American plant owners will want a look at the new pressurizer results too.<\/p>\n<p>The pressurizer piece won\u2019t be the last thing to leave Fessenheim in a shipping box. EDF says it\u2019ll keep pulling samples out of the plant until 2034.<\/p>\n","protected":false},"excerpt":{"rendered":"KeysQuestions4Vehicle1 France just used a remote-controlled laser to carve a 1,455-pound chunk out of a retired nuclear reactor&#8217;s&hellip;\n","protected":false},"author":2,"featured_media":800646,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[84,59,56,54,55],"class_list":["post-800645","post","type-post","status-publish","format-standard","has-post-thumbnail","category-business","tag-business","tag-gb","tag-uk","tag-united-kingdom","tag-unitedkingdom"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/800645","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/comments?post=800645"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/800645\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media\/800646"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media?parent=800645"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/categories?post=800645"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/tags?post=800645"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}