Working with TXU, the plant's owner, a Bechtel team replaced four steam generators and a reactor head during a planned outage that lasted just 55 days-- eight days less than the previous record for steam generator replacement (SGR).
Located about 60 miles southwest of Dallas, Comanche Peak features two units, each capable of generating approximately 1200 megawatts of electricity. The project involved replacing the steam generators in Unit 1, each of which was about 70 feet long and 15 feet in diameter and weighed around 400 tons.
To remove and replace the steam generators, crews had to cut an opening high in the wall of the containment structure enclosing the steam supply system and erect an outside lift system capable of handling the components. It was the tallest system of its kind ever used on an SGR job. In addition, the crane inside the structure could not lift either the old or new generators, so a new lift system was implemented inside the containment structure as well.
The four new high-efficiency steam generators were built in Spain. They traveled by ocean to Houston and continued to Comanche Peak via special train. The new reactor head, also fabricated in Spain, was outfitted with new control rod drives in Pennsylvania and transported by barge to Houston, then trucked to the site.
Over the past two decades, Bechtel has performed the majority of SGR projects in the United States, replacing aging components at more than 30 plants, including Arizona's Palo Verde Nuclear Generating Station, the largest commercial nuclear power plant in the country.
Media Relations Manager