ML18082A228
| ML18082A228 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 04/15/1980 |
| From: | Mittl R Public Service Enterprise Group |
| To: | Parr O Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8004250393 | |
| Download: ML18082A228 (2) | |
Text
OPS~G Public Service Electric and Gas Company 80 Park Place Newark, N.J. 07101 April 15, 1980 Director of Nuclear Reactor Regulation
- u. s. Nuclear Regulatory Commission Washington, D.C.
20555 Attention:
Mr. Olan D. Parr, Chief Gentlemen:
Light Water Reactors Branch 3 Division of Project Management STEAM GENERATORS NO. 2 UNIT SALEM NUCLEAR GENERATING STATION DOCKET NO. 50-311 Phone 201/430-7000 We are in receipt of your letter dated March 27, 1980, requesting that (1) inspection ports be installed in the Salem 2 steam generators prior to start up after the first refueling and (2) the Row 1 tubes in the steam generators be plugged prior to the start of operation.
These requirements have been discussed with members of your staff.
The following information is provided in support of our position that these modifications are not necessary for S,alem 2.
Plugging the first row of tubes would remove the capability for early detection of the onset of denting.
It has been determined that tubes without flow do not dent as rapidly as tubes with flow due to the lack of temperature differential in a non-flowing tube.
Differences in the severity of denting in tubes with flow versus tubes with no flow have been made from an analysis of existing operating plants, as well as through research work done by the steam generator Owners Group.
Inspection of Salem 2 tubes through the existing hand hole can be performed and has been demonstrated at Salem for visual inspections.
Inspection above the upper support plate is not limited to the first row of tubes.
A true representation of the steam generator condition would not be available if the tubes were plugged.
Eddy current probes are now available which can negotiate the small radius curvature of the Row 1 tubes with reasonable accuracy such that problem areas can be easily identified.
A baseline inspection is currently being performed with a new probe designed for close bends.
The Energy People 95-0942
Mr. Olan 4/15/80 Removal of tube sections for analysis through the inspection port would be limited to the Row 1 tubes.
Removing tubes that were plugged would not provide representative material subjected to service conditions.
The Salem plant is equipped with full flow condensate polishing demineralizers and a feedwater bypass to the condenser to provide feedwater chemistry control which will decrease the potential for corrosion and contaminants, as well as subsequent tube or support plate damage.
Rigorous procedures for controlling air inleakage (reducing oxygen) and circulating water inleakage (reducing contaminants) to the condensate system reduces the potential for corrosion and contaminants and subsequent denting or damage to tubes and/or support plates.
Participation in the Steam Generator Owners Group has provided PSE&G with a better understanding of the cracking, corrosion and denting mechanisms and methods for mitigating problems with steam generators.
These methods include
- blowdown control, sludge lancing, periodic soaking and closer control of oxygen and contaminant ingress to the steam generators.
Based on the above, PSE&G believes it to be unnecessary to plug the Row 1 tubes in the Salem 2 steam generators at this time.
Additionally, the installation of inspection ports is also believed to be unnecessary, since the inspection capabilities at Salem, both visual and with internal probes, have been sufficiently developed to obtain valid information regarding the condition of the steam generators.
The continuing efforts of the Steam Generator Owners Group are expected to provide additional information, as well as improved inspection equipment and procedures, to further reduce the incidence of the failures in steam generators.
Should you have any questions, do not hesitate to contact us.
Very truly yours, Rfitiiil-R. L. Mittl General Manager -
Licensing and Environment Engineering and Construction