Wolf Creek Evaluations & Plant Upgrades

Wolf Creek Evaluations & Plant Upgrades

Location: Burlington, Kan.

Client: Wolf Creek Nuclear Operating Corp.

Completion Date: 2009-present

Since 2009, Burns & McDonnell has provided evaluation and engineering support services at Wolf Creek.

During Wolf Creek’s Refueling Outage 17, Burns & McDonnell personnel evaluated the high-profile and high-risk pressurizer auxiliary spray line, which had the potential to extend the outage due to condition concerns. In examining the line for chloride stress corrosion cracking, Burns & McDonnell determined that the required inspections could be completed during the next refueling outage rather than extending the current outage. The Nuclear Regulatory Commission reviewed the disposition and was satisfied that the engineering rigor was good and had no further comment or involvement.

During the same refueling outage, Burns & McDonnell also conducted the auxiliary feedwater pipe stress analysis, a critical path. The overstressed conditions were evaluated and the most efficient path was determined to minimize the outage impact. New pipe supports were added to alleviate the overstressed condition, an effort praised in the industrial maintenance and plant operation (IMPO) audit.

Turbine Rotor Replacement Project

Burns & McDonnell is providing engineering support for turbine rotor replacement. This includes the preparation of design change packages (DCP), succinctly articulating an evaluation of downstream system effects and feedback from calculation reviews. DCPs also are being developed in relation to evaluations of turbine support, cooling water and steam cycle subsystems.

The company's role also includes structural evaluations of the turbine generator foundation pedestal to ensure that the foundation meets the strict performance criteria established by the manufacturer of the replacement turbine rotor. Additionally, Burns & McDonnell is coordinating with the equipment manufacturer to evaluate existing plant structures for heavy equipment travel paths and lay-down space. Finally, Burns & McDonnell is engineering an innovative temporary equipment storage system that will maximize floor space and facilitate logistic operations during the turbine rotor replacement.

Burns & McDonnell has reviewed various causes for the essential service water (ESW) exposed piping wall thinning mechanisms. This includes a thorough review of the plant water hammer events during the Engineered Safety Features Actuation System (ESFAS) testing. The company has also proposed technical solutions to avoid water hammer events during outage testing or during loss of off-site power (LOOP)/loss of coolant accident (LOCA) events.