Georgia Power announced that the top heads are now placed on both units 3 and 4 at the Vogtle expansion project. 

The final major lifts inside the containment vessels are completed, the utility reported. The Unit 4 top head was placed last Friday.  The milestone comes approximately a year after the Unit 3 containment vessel top was lifted into place.

The containment vessel is a high-integrity steel structure that houses critical plant components. The top head is 130 feet in diameter, 37 feet tall, and weighs nearly 1.5 million pounds, more than two fully-loaded jumbo jets. It’s comprised of 58 large plates, welded together, each more than an inch and a half thick.

“Placement of the Unit 4 top head is a culmination of the hard work and dedication of the Vogtle 3 & 4 team as we continue on the path to operation,” said Vogtle 3 & 4 Construction Executive Vice President Glen Chick.

Prior to lifting the containment vessel top head, workers successfully completed the placement of the 300-ton polar crane inside the Unit 4 containment vessel. Once the unit is in operation, the polar crane will be used during refueling outages to disassemble the reactor vessel and remove the reactor vessel’s integrated head package, which weighs approximately 475,000 pounds and contains more than three miles of specialty electrical cables.

The crane has been turned over to the project’s Initial Test Program, and the team will run the crane through various tests over the course of the next month to help ensure design requirements have been met and that all crane functions are operational. After testing, the crane will be used to assist in construction activities to place components inside the reactor vessel.

Significant progress continues to be made at the construction site, with the project now approximately 84% complete.