Frequently Asked Questions

 

What type of engineering services do you offer?

I offer engineering and diagnostic support for nuclear power stations. Among other services, I provide motor-operated valve (MOV) diagnostics and support, VIPER diagnostics, IN 92-18 MOV design calculations, 24-month fuel preventive maintenance reviews, and license extension activities with respect to environmental qualifications.

Normally, I function in a staff-augmentation role where all work is performed under the client’s Quality Assurance program and reviewed by station personnel. Turnkey projects are possible, though I prefer a staff-augmentation role. I am available to work on-site or remotely from the Sealy Engineering offices.

What is your engineering background? What are your qualifications?

I have been working in the nuclear power industry since 1978, when I started as a Draftsman with Duke Power. I worked on staff at Duke for more than 20 years, where I served as a Quality Assurance Technician, Designer, Mechanical Technician, Associate Engineer, and Lead Engineer. In 1998, I left Duke to found Sealy Engineering, where for more than 10 years I have been providing engineering diagnostics and support services.

I have a bachelor’s in Mechanical Engineering from Clemson University, and I am a licensed Professional Engineer in North and South Carolina. Each year, I undergo all the training requirements in order to maintain my PE license and to ensure I am up to speed on the latest regulations set forth by the Nuclear Regulatory Commission.

When are you available?

The bulk of my work each year is comprised of outage support for Duke Energy’s three Carolina nuclear stations—Catawba, McGuire, and Oconee. This work is scheduled in the fourth quarter of the previous year, so if you have a major project in mind, it’s best to contact me six months to a year in advance.

What are your rates?

In general, I charge an hourly rate, plus a daily per-diem when travel is involved. On rare occasions, a rate per-project can be arranged. If you have a project in mind, please contact me for my current rates.

What is involved with MOV setup calculations?

The MOV setup calculations incorporate the valve and actuator design and system conditions to evaluate the ability to perform its safety functions. A setup window is the typical result for MOV setup calculations, and consists of:

  • The minimum closing thrust required to assure operability during design basis events;

  • The maximum allowable thrust (or torque) to assure the actuator doesn’t stall prematurely during undervoltage conditions;

  • The maximum allowable thrust (and/or torque) with inertia to assure that no structural limits are exceeded; and

  • The maximum available thrust (and/or torque) available to open the valve.

  • The maximum design margin is also determined with the setup calculations.

    What is typically performed during diagnostic test analysis?

    The MOV control switches are set with the aid of diagnostic equipment. The analysis evaluates the valve and actuator performance with respect to the setup calculations to assure the valve will perform its safety function. To be conservative, calculation assumptions such as packing loads, degradation, instrument error, and torque switch repeatability are verified. If the valve will not perform its safety function, the calculation is updated with the field information, and the actual setup is verified to be within the adjusted setup window. Degradation such as stem nut wear and the coefficient of friction is also evaluated. Finally, the setup margin is calculated and the test frequency, as required by GL 96-04, is determined.

    What is involved with an IN 92-18 MOV evaluation?

    NRC Information Notice 92-18 requires MOVs to be evaluated for the “Potential for Loss of Remote Shutdown Capability During a Control Room Fire.” In such an event, the MOV may travel open (or closed), bypassing all the control switches. The evaluation consists of testing the actuator capability at a stall condition and comparing it to the structural limits of the various components in the actuator and valve. In many cases, pressure boundary integrity is sufficient, but if the valve must be repositioned after the fire, alternatives must be determined—for example, manual operation, actuator replacement, or component redesign.