Document: NUREG-0800
Document ID: 217aa53e-c4ac-4a8f-b1b6-968ad75d68ab
Document Type: srp
Title: INSERVICE TESTING OF PUMPS AND VALVES
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070368.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.9.6
CFR Part: 
CFR Title: 

Content:
d considering such parameters as differential pressure, fluid flow, undervoltage, temperature, seismic effects, dynamic effects, and appropriate combinations. The design torque and thrust requirements should be determined allowing sufficient margin to account for diagnostic equipment inaccuracies. (d) At the point of control switch trip, any loss in actuator torque and/or stem thrust that is related to increasing differential pressure and flow conditions (referred to as "load-sensitive MOV behavior") should be identified. The control switch trip setpoints should include margins for load-sensitive MOV behavior, control switch repeatability, diagnostic equipment error, and degradation of the assembly and its components. (e) The total thrust and torque that is delivered by the MOV under static and dynamic conditions, including allowances for diagnostic equipment inaccuracies and control switch repeatability, should be compared to the allowable structural and undervoltage motor capability limits for the individual parts of the MOV. (f) Remote position indication testing should be conducted, if applicable, to verify that proper disk position is indicated in the control room. (2) In addition to the inservice testing described in subsection II.2.b, periodic inservice testing of MOVs should be conducted to permit an assessment of continuing operability under design basis conditions. (a) Periodic testing should be conducted that objectively demonstrates continuing MOV capability to open and/or close under design- basis conditions, as established in subsection II.2.c(1). A risk-based approach may be used to prioritize valve test activities, such as frequency of individual valve tests and selection of valves to be tested. The valve test program should ensure that safety-related MOVs will remain operable until the next scheduled test. The importance of the valve should be considered in determining an appropriate mix of exercising and diagnostic 3.9.6-7 DRAFT Rev. 3 - April 1996