The last of eight replacement steam generators has been lifted into place at Bruce unit 6, marking an important milestone in the ongoing Major Component Replacement (MCR) project which will add 30-35 years to the Candu unit's operational life.

Bruce 6's final steam generator is lifted into place 6 (Image: Bruce Power)

Unit 6 contains eight steam generators, each weighing some 320,000 pounds (145 tonnes). The steam generators were lifted through the powerhouse roof enclosure using Mammoet's PTC-35 crane, one of the largest in the world, and set into place with only millimetres of tolerance. Before the first lift, a 3D layout was prepared of the steam generators by laser topography to verify dimensions.

The new steam generators were fabricated at BWXT in Cambridge, Ontario and shipped to the Bruce site late last year. This 'Made in Ontario' nuclear injects billions into Ontario's economy and creates and sustains 22,000 high-skilled jobs annually, said Bruce Power Executive Vice President, Projects & Engineering Eric Chassard.

"These new steam generators will be in service for many decades providing clean, reliable power to Ontario homes and businesses," he said. "This is a culmination of many years of hard work and collaboration between Bruce Power and our partners like SGRT, BWXT, Mammoet, Nuvia and the Building Trades Unions."

The vendor responsible for replacing the Unit 6 steam generators is the Steam Generator Replacement Team (SGRT), a 50:50 joint venture between Aecon and SGT (a partnership between Framatome and United Engineers & Constructors). The consortium has also been awarded a contract for the same scope on Bruce units 3 and 4 which are yet to undergo MCR.

The MCR project is part of Bruce's Life-Extension Program, a long-term investment programme to update all eight Bruce reactors and secure the site's operation until 2064. Bruce 6 is the first of six units to undergo MCR, which includes the replacement of key reactor components such as steam generators, pressure tubes, calandria tubes and feeder tubes. The MCR of Bruce 6 began in January 2020, and is expected to be finished in 2024. Refurbishment of the final reactor, unit 8, is scheduled to be completed in July 2033. Units 1 and 2 have already been refurbished.

Researched and written by World Nuclear News