Civilian workers reportedly tried to cut corners by sticking some bolts back on to vital cooling pipes, but the hasty mend was discovered when one fell off
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Civilians said to be carrying out work on HMS Vanguard – repairs that started in 2015 – reportedly glued some bolts back, that held insulation in place, on to essential cooling pipes, that had been sheared off through over-tightening.
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Alarmed Ben Wallace was reported to be angry at the news, demanding a meeting and “assurances about future work”, while a Navy source was reported to have said: “It’s a disgrace. You can’t cut corners with nuclear."
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The bungled repair was reportedly only discovered when one bolt fell off during checks aboard the 16,000-ton ballistic missile-armed vessel, which was first launched in 1992.

HMS Vanguard was undergoing a dry dock refurbishment and refuel at HMNB Devonport, Plymouth, which was £300million over budget.

https://www.mirror.co.uk/news/uk-news/shoddy-super-glue-repairs-trident-29091480