NTS Huntsville Assists in Successful Snubber Replacement at Farley Plant

On Tuesday, October 28th, 2014 NTS Huntsville assisted in the successful replacement of two snubbers at the Joseph M. Farley Nuclear Plant in Alabama. The outage on Unit 2 for refueling and maintenance began on October 15th and began generating electricity on November 19th.During the replacement a team of two individuals (Bryan Baugher, NTS and Wes Williams, WPS) worked in a basket suspended 130 feet in the air to reach the snubbers. Because of the risk involved, a rescue team and quality control were also on hand to monitor the job.

Photo from Thomas Sexton, Joseph M. Farley Nuclear Plant

A snubber is a device which performs much like your vehicle’s shock absorber and comes in many sizes and types, such as mechanical or hydraulic. The purpose of a snubber within the nuclear power plant is to help protect support structures and piping from the rigors of vibration and heat induced expansion and contraction during operation, and most importantly seismic events. The American Society for Mechanical Engineers along with the US Nuclear Regulatory Commission mandate codes and technical specifications for periodic testing of in-plant safety equipment. During the spring and fall, when power demand is low, most plants undergo refueling outages. During this time, such as the case with the Farley plant, upgrades, testing and maintenance are performed. The Regulatory Commission codes require “sample’ testing or replacement of a percentage of snubbers during these outages. Testing and refurbishment can be performed at NTS Huntsville, but most snubber activities are performed on-site at the nuclear power plant. NTS personnel are dispatched to plant sites around the country for weeks at a time, many working up to 12 hours a day, six days a week. They maintain a fleet of testing and repair trailers, which contain all the equipment to test and perform repairs for most any type of snubber. Thanks to a professional, experienced and dedicated staff, nuclear plants such as Farley know the Safety Relief Valve and Snubber testing services provided by the NTS Nuclear Division are a major component in maintaining critical outage schedules.