Document: NUREG-0800
Document ID: 1dbfaffa-d13d-47e0-9536-f667eb85f6b8
Document Type: srp
Title: CONDENSATE AND FEEDWATER SYSTEM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052350091.pdf
Revision Date: 2023-06
Chapter: 10
Section ID: 10.4.7
CFR Part: 
CFR Title: 

Content:
or the Westinghouse and Combustion Engineeering PWR designs which use top-feed steam generators. BRANCH TECHNICAL POSITION In CP and OL application reviews, the staff requires the applicant to provide the following design capability and verification: Top-Feed Steam Generator Designs To eliminate or reduce possible water hammer in the feedwater system: a. Prevent or delay water draining from the feedring following a drop in steam generator water level by means such as top discharge J-Tubes and limitng feedring seal assembly leakage. b. Minimize the volume of feedwater piping external to the steam generator which could pocket steam using the shortest possible (less than seven feet) horizontal run of inlet piping to the steam generator feedring. c. Perform tests acceptable to NRC to verify that unacceptable feedwater hammer will not occur using the plant operating procedures for normal and emergency restoration of steam generator water level following loss of normal feedwater and possible draining of the feedring. Provide the procedures for these tests for approval before conducting the tests and submit the results from such tests. d. Implement pipe refill flow limits where practical. Preheat Steam Generator Designs 1. Minimize the horizontal lengths of feedwater piping between the steam generator and the vertical run of piping by providing downward turning elbows immediately upstream of the main and auxiliary feedwater nozzles. 2. Provide a check valve upstream of the auxiliary feedwater connection to the top feedwater line. 3. Maintain the top feedwater line full at all times. 10.4.7-9 Rev. 3 - April 1984 4. Perform tests acceptable to NRC to verify that unacceptable feedwater hammer will not occur using plant operating procedures for normal and emergency restoration of steam generator water level following loss of normal feedwater. Also perform a water hammer test at *% of power by using feedwater through the auxiliary feedwater (top) nozzle at the lowest feedwater