July-August 2019 NPJ

48 NuclearPlantJournal.com Nuclear Plant Journal, July-August 2019 Upgrade of... ( Continued from page 47) Reactor Safety The Surry V-Wrap™ CFRP System solution aligns with nuclear industry initiatives for improving Reactor Safety by increasing CW and SW system reliability and lowering the risk of unplanned outages. The use of a CFRP system strengthening process requires an understanding of the key engineering attributes (e.g., physical, chemical, and environmental) which influence a high- quality installation. Dominion Energy developed a technical specification and implemented the Dominion Energy Quality Assurance Program (QAP). This specification was performance based, considered best practices, required early engagement of qualified contractors, and included results from a bench-marking review of similar solutions implemented in nuclear, fossil, commercial, municipal, and industrial facilities. The V-Wrap™ CFRP System was selected as the preferred solution and is comprised of high-strength carbon fiber and glass fiber fabrics, which are fully saturated in a two-part, Volatile Organic Compound (VOC) free, 100% solids epoxy matrix. As described below, four areas were interwoven by the Project Team in this FOAK project to define the performance criteria for the CFRP System solution to improve Reactor Safety: 1. Design Engineering (SGH): Even if the host steel pipes continued to degrade, the V-Wrap™CFRP system was designed to have the necessary strength, reliability, and durability, to address the design basis loading conditions over a service life of 50 years, continuing to fulfill its intended design functions. Based on the design basis, the V-Wrap™ CFRP system is designed as a standalone system capable of resisting all design loads without relying on any strength contribution from the host steel pipe, except for load transfer and water tightness at the terminal ends of the repair. The design is performed by calculating the strains and stresses in CFRP under the specified design loads using closed-form solutions for flexible pipe and by checking the relevant limit states (i.e., failure modes) of the CFRP repair system. 2. Materials (Structural Technologies): Strict manufacturing controls and special process verifications were required by the Dominion Energy specification. V-Wrap™ CFRP System materials were commercially dedicated using a Commercial Grade Dedication (CGD) process under the controls of a 10CFR50, Appendix B Quality Assurance Program (QAP). Structural Technologies’FOAKCGD process identified critical characteristics, acceptance methods, acceptance criteria, and Sampling Plans. Sampling Plans were developed in accordance with EPRI Document No. TR-017218-R1. January 1999, “Guideline for Sampling in the Commercial-Grade Item Acceptance Process”. Upon receipt of V-Wrap™ CFRP System materials from the raw material manufacturers, critical characteristics were verified by inspection and/or testing. Once complied, Structural Technologies Subject Matter Experts (SMEs) evaluated inspection and testing results to validate that all critical characteristics and acceptance criteria had been met. Upon sign-off of inspection and testing results by the SMEs, a Certificate of Compliance (CoC) was issued to Dominion ENERGY. 3. Installation (Structural): The V-Wrap™ CFRP System laminates are bonded both longitudinally and circumferentially to the interior surface of the CS pipe surface, forming a structural lining within the pipe. Special details were developed by the Design Engineers (SGH) for terminations, outlets, Inspection Team.