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SUMMARY OF QUALIFICATION TEST RESULTS FOR ASCO NS-2 SOLENOID VALVES WITH NICOTEF COATING
Two parallel qualification programs were initiated in late 1989 to qualify the NS-2 line of solenoid valves. The NS-2 series was developed to expand and enhance those areas of performance upon which previous qualification efforts were based. Six of the NS-2 test specimens utilized the Nicotef coating system to reduce friction between the valve seats and discs. The six test specimens are identified in Table 3.1. The qualification test program is documented in ASCO Test Report No. AQR-21691. This summary test report contains excerpts from the full report that are relevant to the performance of the Nicotef coating system used on these six test specimens. In summary, the six valves performed acceptably throughout the entire test program except for a cracked spring in one specimen identified during post-DBE baseline testing. The performance of these six valves provides evidence that the Nicotef coating system is an acceptable design change for similar NP valves.
Three groups (A, B, and C) of eleven ASCO Catalog NS-2 solenoid valves were subjected to a qualification test program in accordance with ASCO qualification specifications. Six of these valves (2 per group) used the Nicotef coating system. The qualification test program consisted of a series of six sequential aging simulation phases; thermal aging, wear aging, pressurization aging, radiation aging, vibration aging and seismic OBE aging. The aging phases were followed by three sequential Design Basis Event (DBE) simulations; radiation, seismic SSE, and environmental DBE. Only the B and C Group valves were exposed to the environmental DBE simulation. In addition, a resonance search was conducted prior to the vibration aging. Baseline testing was performed prior to the start of the aging phases, and was repeated at the conclusion of each aging phase with the exception of pressurization aging. At the conclusion of the post environmental DBE baseline test, the test valves were disassembled and visually inspected for component degradation caused by the various exposure environments.
Testing was conducted during the period from June, 1991, through May, 1996. Thermal aging simulation, wear aging, pressurization aging, baseline testing, vibration aging, seismic OBE aging, seismic DBE, and resonance search testing were all performed at the facilities of Automatic Switch Co., in Florham Park, NJ. Radiation aging simulation and Radiation DBE exposure were conducted at the facilities of Isomedix, Inc., Parsippany, NJ. Environmental DBE simulation was performed at the facilities of Wyle Labs., Norco, CA.