Nuclear energy operator Exelon Nuclear has installed GEH’s Marathon Ultra CRBs at its Peach Bottom atomic power plant in Pennsylvania. The power station has a generation capacity of approximately 2,200MW of electricity.
Marathon Ultra is the latest addition to GEH’s portfolio of Marathon CRBs. CRBs are long, cruciform metal-tube components that contain neutron-absorbing material and are positioned adjacent to nuclear fuel assemblies within the reactor core. Operators remotely adjust the position of these control rod blades to manage core reactivity levels.
Kevin Lagasse, senior vice president of nuclear services at GEH, said: “We are pleased to work closely with Exelon to demonstrate how our advanced technologies and services can be deployed to help energy companies around the world achieve greater operational and cost efficiencies with their nuclear power plants.”
Exelon Nuclear installed two Marathon Ultra medium duty control rods as ‘lead use’ assemblies in reactor unit 3 at the Peach Bottom plant during a recent regular refueling and maintenance outage. A lead use assembly is inserted in a reactor core to verify the control rod’s performance.
GE said that the new Marathon Ultra offers additional value because of its simplified neutron-absorber tubing design. It also offers reliability by incorporating a larger gap between the boron carbide (B4C) capsule and the neutron absorber tube, providing extra space to counter any capsule swelling, minimizing potential strains on the absorber tubing.
The Marathon Ultra design also incorporates a low-cobalt and radiation-resistant stainless steel absorber tube. These design features help Marathon Ultra achieve its full engineered lifetime without mechanical limitation.
GEH designs and builds its CRB product line at its headquarters site in Wilmington, North Carolina. Recently, the company submitted a licensing topical report to the US Nuclear Regulatory Commission for the next offering in the Marathon Ultra product line, the Marathon Ultra HD (high duty), which is expected to offer a longer lifetime for higher-duty applications.
