Media Center
Clevis Bolt Replacement

Solutions for All of Your Internals Needs

CRGT Replacement & Shuffles

If inspections indicate unacceptable wear on the Control Rod Guide Tubes (CRGT), Framatome has the ability to perform removal operations and install new CRGTs in the upper internals. CRGTs may also be swapped with spare locations.

Internals Bolting Replacement – Baffle Bolts

We performed the first U.S. nuclear plant Baffle Bolt NDE inspection under new Materials Reliability Program (MRP-227) guidelines for Pressurized Water Reactor Internals Inspection and Evaluation. Our team completed the record exam of 1,088 bolts 17 hours ahead of schedule. Plus, the project was completed under the exposure estimate with zero foreign material exclusion (FME) incidents. Worldwide, Framatome has removed or replaced more than 8,700 core barrel and baffle-to-former bolts to date. Additionally, we can perform inspection in parallel with bolt replacement activities, further minimizing outage time.

Internals Bolting Replacement – Clevis Bolts

Framatome performed an unprecedented replacement of clevis bolts located on the lower radial support system of the reactor vessel at a U.S. plant. To complete the underwater bolt replacement, Our engineers designed a unique tooling system to perform work remotely from refuel floor platforms. Lessons learned from this project will improve the efficiency of future bolt and reactor vessel internals replacements.

The project won the Framatome (formerly AREVA NP) Vendor Award for NEI’s Top Industry Practice Awards.

Clevis Bolt Replacement

  • Proven production rates based on experience
  • All tooling and processes are based on existing bolt replacement equipment that has been used on over 8,700 previous applications
  • EDM process is used for all machining operations to avoid FME concerns
  • Improved bolt design for lower stress concentrations
  • Crimp cup locking mechanism – No welding required for installation

Highlights of the AREVA Repair Process

• Thermal Sleeve Removal (If Applicable)

• Roll Nozzle in Repair Region

• Machine Weld Prep & PT Weld Area

• Perform Ambient Temperature Temper Bead Structural Weld

• Prepare Welded Surface For NDE

• Perform Post-Repair UT & PT

• Remediate Rolled and Repaired Areas

• Install Replacement Thermal Sleeve (If Required)

Join the Conversation
@AREVAus AREVAinc on Facebook AREVAinc on YouTube AREVA on LinkedIn
Contact Us

Lisa Hawkins
Business Development Manager, CR&R
Tel: 434.832.2858