Document: NUREG-0800
Document ID: 48fcca4d-4efe-4600-b4ca-9911efb87843
Document Type: srp
Title: and 5.2.1.2.
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070446.pdf
Revision Date: 2023-06
Chapter: 5
Section ID: 5.2.1.1
CFR Part: 
CFR Title: 

Content:
o assure that the reactor coolant boundary and associated auxiliary systems have been designed, fabricated, erected, and tested so as to have an extremely low probability of abnormal leakage, of rapid failure and of gross rupture, during normal operation and anticipated operational occurrences. The primary side of the steam generator is designed and fabricated to comply with ASME Class 1 criteria as required by the staff. (The secondary side pressure boundary parts of the steam generator will *Include material within parentheses as applicable. 5.4.2.1-11 DRAFT Rev. 3 - April 1996 be designed, manufactured, and tested to ASME Class 1 criteria although the staff required classification is ASME Class 2.)* The crevice between the tube sheet and the inserted tube will be minimal because the tube will be expanded to the full depth of insertion of the tube in the tube sheet. The tube expansion and subsequent positive contact pressure between the tube and the tube sheet will preclude a buildup of impurities from forming in the crevice region and reduce the probability of crevice boiling. (The tube support plates will be manufactured from ferritic stainless steel material, which has been shown in laboratory tests to be corrosion resistant to the operating environment.) (The tube support plates will be designed and * manufactured with broached holes rather than drilled holes. The broached hole design promotes high velocity flow along the tube, sweeping impurities away from the support plates locations.) (The tube support structure will be *50 manufactured to the egg crate design. The egg crate design eliminates the narrow annular gap at the tube supports, because the support may contact the tube at only four lines on the tube circumference, and provides almost complete washing of the tube surface with steam generator water.)* If austenitic stainless steel is utilized, the review includes appropriate findings from SRP Section 5.2.3, "Reactor Coolant Pressure Boundary