Document: NUREG-0800
Document ID: c372af3e-1f44-4817-b7ae-01b1c087f547
Document Type: srp
Title: STEAM GENERATOR BLOWDOWN SYSTEM (PWR)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052350093.pdf
Revision Date: 2023-06
Chapter: 10
Section ID: 10.4.8
CFR Part: 
CFR Title: 

Content:
ined. The steam generator tubes are part of the reactor coolant pressure boundary, and these tubes could be degraded by adverse chemistry conditions on the secondary site. The SGBS primary function is to remove steam generator secondary side impurities and thus assist in maintaining acceptable secondary side water chemistry in the steam generators. Specific Criteria necessary to meet the relevant requirements of GDC 1, 2, and 14 are as follows: 1. The SGBS is sized to accommodate the design blowdown flow needed to maintain secondary coolant chemistry for normal operation, including anticipated. operational occurrences. 10.4.8-2 Rev. 2 - July 1981 2. Equipment capacities are based on design blowdown flow rates and are such that temperature limits for heat-sensitive processes are not exceeded. 3. Instrumentation and automatic controls ensure operation within design parameters. 4. The design of the SGBS is seismic Category I and Quality Group B, from its connection to the steam generator inside primary containment up to and including the first isolation valve outside containment. The design of the SGBS downstream of the outer containment isolation valves is in accord with the.provisions of Regulatory Guide 1.143, Position C.1.1. III. REVIEW PROCEDURES The reviewer selects and emphasizes material from this SRP section as may be appropriate for a particular case. 1. a. CMEB considers the pressure, temperature,-flow rate, secondary coolant chemistry, main condenser water inleakage, and primary-to-secondary leak- age to determine whether the SGBS design has included the effects of normal operation and anticipated operational occurrences (e.g., main condenser inleakage or primary-to-secondary leakage). UMEB determines that the design parameters are reasonable. If the proposed system includes processes which are heat-sensitive (e.g., demineralization or reverse osmosis), CMEB verifies that the design includes instrumentation and controls to protect the temper-