ML18079B097
| ML18079B097 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 10/05/1979 |
| From: | Librizzi F Public Service Enterprise Group |
| To: | Schwencer A Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML18079B098 | List: |
| References | |
| NUDOCS 7910120226 | |
| Download: ML18079B097 (2) | |
Text
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Public Service Electric and Gas Company 80 Park Place Newark, N.J. 07101 Phone 201 /430-7000 October 5, 1979 Director of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, D. C. 20555 Attention:
Mr. A. Schwencer Gentlemen:
Chief Operating Reactors Branch #1 Division of Operating Reactors CHEMICAL AND VOLUME CONTROL SYSTEM (CVCS) PIPE CRACKS DUE TO EXCESSIVE CHARGING PUMP VIBRATIONS NO. 1 UNIT SALEM GENERATING STATION DOCKET NO. 50-272 -
Your Letter dated August 22, 1979 In response to your above mentioned letter, we wish to comment as follows:
To reduce vibrations of piping in the subject line to an accept-able level, the following steps were taken:
- 1.
Two leaf spring dampeners were added to the 4" Safety Injection line.
- 2.
Revised one of the leaf spring vibration eliminators to a friction plate vibration eliminator on the suction line.
- 3.
Added friction plate vibration eliminator on the dis-charge line.
- 4.
Rerouted pump suction line to eliminate gas pockets, increased pipe schedule, added friction plate type vibration eliminators to the 4" suction line and rein-forced the 8 11 A-straps on the 8 11 suction header.
As a result of the above, the pipe vibrations have been reduced to an acceptable level.
Periodic inspections of 4" Safety In-jection branch and 8 11 suction header lines indicate that the system is stable and there are no visual vibrations.
Z-r~ II 7910120~
The Energy People 95-2001 (400M) 9-77
Director of Nuclear Reactor Regulation Mr. The number 13 charging pump suction and discharge valves will be inspected prior to returning the Unit to service to insure that there are no pump/valve problems.
Since piping for Salem #1 and #2 Units is similar, we are also providing a copy of quantitative data at pump discharge and discharge headers from a program initiated through our Energy Laboratory to monitor vibration levels during Hot Functional Testing for #2 Unit Salem.
Franklin Institute Research c~nter, Philadelphia, Pa., has been retained as a consultant to advise and review the test procedure for this program.
The test was conducted in accordance with the attached procedure 11Vibratory Analysis of No. 23 Reciprocating Charging Pump Piping 11 The test results indicate that there is a minimum vibration in the piping system at various pump discharge pressures.
It was also concluded that an increase in piping vibration amplitude occurred when the vibration dampeners were physically removed from the piping system.
The same results were obtained when eliminating vibration dampeners on the suction side.
These data are indicative of the effectiveness of Unit #1 correc-tive action.
The test results are presented in the attached report in Tables 1 and 2.
Should you require additional information in this regard, please do not hesitate to contact us.
Very truly yours, F. ?.~~
General Manager -
Electric Production
Attachment:
Vibration Analysis of No. 23 Reciprocating Charging Pump Piping Salem Generating Station Report prepared by PSE&G Research Corp.