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D. Radiation Aging Simulation:

This testing simulates the effect of radiation on non-metallic parts of a valve. Since no change has been made to the elastomers in this valve, this portion of the qualification still applies. Elimination of the run-in oil and use of water as an o-ring assembly aid do not adversely affect valve response to this simulation. The Nicotef coating is a proprietary blend of nickel and Teflon. The nickel is unaffected by radiation. Teflon is a fluropolymer and is susceptible to radiation degradation; however, this degradation does not adversely affect the Teflon's ability to reduce sliding friction between the stem/disc and seat or the ability of the Nicotef to bond to the base materials. This conclusion is based on the qualification test results discussed in Appendix A for valves with the Nicotef coating after radiation aging simulation.

E. Vibration Testing Simulation:

This testing simulates the effect that system induced vibrations would have on a valve throughout the valves service life. Elimination of the run-in oil and use of water as an o-ring assembly aid do not adversely affect valve response to this simulation. The Nicotef coating does not adversely affect the ability of the valve to sustain system-induced vibration. This conclusion is supported by the supplemental wear aging testing discussed above which demonstrates that the Nicotef does not cause binding, failure to shift, unacceptable wear, or unacceptable seat leakage. These conclusions are also supported by the NS testing discussed in Appendix A

F. Seismic Aging Simulation:

This testing is designed to simulate the effect of minor earthquakes during normal plant operations. Elimination of the run-in oil and use of water as an o-ring assembly aid do not adversely affect valve response to this simulation. The Nicotef coating does not adversely affect the ability of the valve to function during the seismic simulation. This conclusion is supported by the supplemental wear aging testing discussed above which demonstrates that the Nicotef does not cause binding, failure to shift, unacceptable wear, or unacceptable seat leakage. These conclusions are also supported by the NS testing discussed in Appendix A

G. Resonance Testing:

This testing is designed to locate the material resonance point of the valve. Since this modification has not called for the introduction of any significant design changes the natural resonance points from previous testing are considered to be valid.

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