ML18047A498
| ML18047A498 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 08/02/1982 |
| From: | Johnson B CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | Crutchfield D Office of Nuclear Reactor Regulation |
| References | |
| REF-SSINS-6820 IEB-82-02, IEB-82-2, NUDOCS 8208050257 | |
| Download: ML18047A498 (4) | |
Text
- consumers Power cmnpa~y General Offices: 1945 West Parnell Road, Jackson, Ml 49201 * (517) 788-1636 August 2, 1982 Dennis M Crutchfield, Chief Operating Reactor Branch No 5 Nuclear Reactor Regulation US Nuclear Regulatory Commission Washington, DC 20555 DOCKET 50-255 - LICENSE DPR-20 PALISADES PLANT - RESPONSE TO IE BULLETIN NO. 82-02 ACTION ITEM 3:
DEGRADATION OF THREADED FASTENERS IN THE REACTOR COOLANT PRESSURE BOUNDARY OF PWR PLANTS The NRC discussed the degradation of threaded fasteners in the Reactor Coolant Pressure Boundary (RCPB) of Pressurized Water Reactor plants in IE Bulletin No. 82-02, dated June 2, 1982.
Consumers Power Company is providing a response for the Palisades Plant to Action Item 3 of the Bulletin by this submittal.
Action Item No 3a:
Identify those bolted closures of the RCPB that have experienced leakage, particularly those locations where leakage occurred during the most recent plant operating cycle. Describe the inspections made and corrective measures taken to eliminate the problem. If the leakage was attributed to gasket failure or its design, so indicate.
Response
In December 1981, while in cold shutdown with Primary Coolant System (PCS) pressure at 150 psig, the 'B' Steam Generator cold leg primary manway was found to be leaking.
The leakage was stopped by retorquing the manway studs and nuts and a procedure revision was issued to require a Quality Control sign-off for final torque completion.
In response to IE Notice 82-06, an inspection of steam generator manway studs was performed in A
April 1982.
A Non-destructive Testing visual (VT-1) examination and
()()/
magnetic particle (MT) examination were performed on all steam generator manway studs.
The VT-1 inspection revealed signs of minor corrosion on 7 of the 20 studs on the 'B' Steam Generator cold leg manway and one each on the 'A' Steam Generator hot and cold leg manways.
One of the corroded studs was removed and a liquid penetration (PT) inspection performed with no indication of defects observed.
An engineering analysis was performed to verify that the existing bolt area met the requirements of the ASME design code.
DMCrutchfield, Chief Palisades Plant
- Response to IEB 82-0 2, Action Item 3 August 2, 1982 Control Rod Drive Mechanisms (CRDM)
During the past operating cycle, several instances of CRDM leakage occurred.
The instances are summarized in the table below:
METHOD OF DATE CRDM No.
DETECTION ACTION TAKEN 11-7-79 12,24,30 a
1 2-12-80 2,9,17,25, a
2 26,31,33, 40,41 5-12-80 6,17,26, a
2 31,43 7-3-80 22 b
1 8-27-80 7
b 1
9-29-80 15,22,23,24 a
1 2-4-81 16 b
1 5-29-81 6
b 1
10-15-81 5,17,18, a
1 23,32 have a - Gasket leakage detected during inspection of CRDMs.
b - Stud corrosion detected during seal replacement.
1 -
CRDM autoclave gasket and studs replaced.
2 - Retorqued CRDM autoclave nuts and studs.
The design of the CRDM closure does not allow for drainage of any gasket leakage.
As a result, even minimal leakage tends to accumulate and boric acid corrosion of the studs may occur.
To alleviate this problem, the original carbon steel studs are being replaced with stainless steel as each CRDM requires maintenance.
Maintenance procedures for the threaded fasteners of the CRDMs have been implemented which address the concerns of Action Item 1 of IE Bulletin 82-02.
Also, as these threaded fasteners are opened for inspection or maintenance they are removed, cleaned, and inspected as required by Action Item 2.
As these inspections are completed, a written report will be submitted to the NRC within 60 days following the completion of the outage during which they are performed as required by Action Item 4.
2
DMCrutchfield, Chief Palisades Plant Response to IEB 82-02, Action Item 3 August 2, 1982 Action Item No 3b:
Identify those closures and connections, if any, where fastener* lubricants and injection sealant materials have been or are being used and report on plant experience with their application, particularly any instances of sec of fasteners.
Include types and composition of materials used.
Response
Palisades has not used any inje~tion sealants or had any instances of SCC in PCS boundary closures.
The following lubricants are routinely used on the PCS fasteners:
3 Neolube Conforms to Military Specification MIL-L-24131B Brian D Johnson Never-Seize Pure Nickel Dow Corning DC-41 Certified Less Than 15ppm halogens, sulfer, lead, mercury and heavy metals.
Senior Licensing Engineer CC Administrator, Region III, USNRC NRC Resident Inspector - Palisades
CONSUMERS POWER COMP ANY Palisades Plant Docket 50-255 License DPR-20 RESPONSE TO IE BULLETIN NO. 82 ACTION ITEM 3 At the re~uest of the Commission and pursuant to the Atomic Energy Act of 1954 and the Energy Reorganization Act of 1974, as amended, and the Commission's Rules and Regulations thereunder, Consumers Power Company submits our response to Action Item 3 of IE Bulletin 82-02, dated June 2, 1982.
CONSUMERS POWER COMPANY R B DeWitt, Vice President Nuclear Operations Sworn and subscribed to before me this 2nd day of August 1982.
- ~~~
Helen I Dempski, Notary Public Jackson County, Michigan My commission expires December 14, 1983.