At Entergy River Bend Station (a 978 MWe BWR located near Baton Rouge, Louisiana) snubber examination and testing have become unwanted expenses with the potential to lengthen planned outages and increase ALARA concerns. This paper presents a new concept for snubber replacement which can be used to expand the “Snubber to Strut” methodology. The E-BAR is a passive gapped support fabricated to be a “drop-in” replacement for snubbers. During normal plant operation the E-BAR functions like a box support, and during dynamic loading the E-BAR limits pipe motion and functions as a seismic restraint. Combining the guidance of WRC-300 [1] (snubber to strut criteria) and the industry practice of installing box supports with 1/16″ gaps between the pipe face and steel frame, generic criteria were developed to facilitate drop in snubber replacements. Replacements based on these criteria do not require re-analysis of the piping system. At the River Bend Station 102 snubbers were identified with thermal movements between 1/16″ and 3/8″. Sixty four snubbers (> 60%) met the generic criteria and were shown to be located at appropriate locations for snubber replacement. Development and explanation of the generic criteria and their applications are discussed here-in.

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