Installation of Limit Stop Devices for Snubber Elimination

摘要

Beaver Valley Unit 1 recently conducted a snubber elimination project where Limit Stop devices were used to replace snubbers. The limit stop (gapped) devices, developed by R.L. Cloud Associates (RLCA) and fabricated by Grinnell, were installed during the 1996 refueling ouage. The effort undertaken to qualify the limit stop installation first involved a review of the one-for-one rplacement criteria without ranalysis as posed in RLCA's Topical Report entitled, "A Methodology, Verification and Applications of Computer Program GAPPIPE," (RLCA, 1994). Following this review, an analytical effort was conducted using the GAPPIPE computer program (RLCA, 1995). This paper presents the results of that analytical effort. Duquesne Light Company and Stone & Webster Engineering Corporation were able to successfully replace or eliminate all of 53 targeted snubbers.