Framatome wins US generator services contract

US utility Dominion Energy has awarded Framatome a contract to provide steam generator services for its fleet of six nuclear power reactors. The inspection and maintenance work - scheduled to take place during outage over the next two years - will partly be carried out using robots.

The "multimillion-dollar" contract covers steam generator inspections planned to take place during eight scheduled outages over the next two years at Dominion's Millstone, North Anna and Surry nuclear power plants, Framatome said. Each plant features two operating pressurised water reactors (PWRs).

The Forerunner robot (Image: INETEC)

Steam generators are used in PWR plants to transfer heat from the reactor coolant into water in a secondary circuit to produce the steam used to power the electricity-generating turbines. PWRs may have up to four "loops", each with a steam generator.

Framatome said it will deploy its Trident probe delivery system as part of the steam generator services to Dominion. This can deliver up to three separate probes to inspect an entire steam generator. The company said the technology reduces dose and inspection time while improving safety and human performance, by utilising robots such as its recently launched Forerunner.

Forerunner is a light, mobile robot developed and manufactured by Croatia's INETEC-Institute for Nuclear Technology. Framatome said the robot's size and design minimises installation and inspection times by providing improved access to the steam generator tubes for inspection and repair. Launched last November, Forerunner's spider-like movements in all working positions, on horizontal or vertical tubesheets, easily adapts to different steam generator geometries. It can also calculate the optimal inspection path using an intelligent path algorithm, which can decreased inspection time by 30%-50%. Forerunner can reach more than 200 tubes in a given stance.

Researched and writtenby World Nuclear News