ML19282D042
| ML19282D042 | |
| Person / Time | |
|---|---|
| Issue date: | 01/10/1978 |
| From: | Novak T Office of Nuclear Reactor Regulation |
| To: | Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML19282D043 | List: |
| References | |
| FOIA-79-98 NUDOCS 7905110055 | |
| Download: ML19282D042 (1) | |
Text
._
[Y
' ' -Background Information to January 10, 1978 _
Note to RSB -- Loop Seals in Pressurizer Surge Line The potential effect of loop seals (i.e., a manometer effect) in a pressurizer surge line en pressurizer level indications was considered by Mr. S. Israel (RSB) back in 1977 as a generic technical matter rather than during the review of any specific plants; however, he did recognize that the locp seal configuration appears to be unique to S&W plant designs.
The nature of the concern for the loop seal deals with behavior as a mancmeter where level changes would be associated with differences y in pressure between the primary system and the pressurizer.
In some transient situations where voids would be formed in the primary system, the pressurizer may not be the hottest point in the system.
This could lead to the manometer effect in the pressurizer.
Since the pressurizer is where the instrumentation is installed to measure system coolant The level, this situaffon could lead to misleading level information.
operator relies,on level indication for the control of makeup flow to the plant system.
Operating experience available at the time that the memorandum '!as prepared did not reveal any situahn for which the operator could not effect safe plant shutdown; consequently, acticns to pursue this natter further at the time were not taken.
This has remained generally true up to The experience of the Tf!I 2 accident, makes it apparent that greater now.
emphasis in the review must be given to this matter.
7905110065 V'