ML20054G879

Responds to IE Bulletin 81-01,Revision 1, Surveillance of Mechanical Snubbers. Mechanical Snubber 23 in Dresden Reactor Cleanup Sys Found Inoperable & Replaced.Quad Cities Snubbers Will Be Tested Per New Tech Spec Requirements

ML20054G879
Person / Time
Site:	Dresden, Quad Cities, 05000000
Issue date:	06/15/1982
From:	Swartz E COMMONWEALTH EDISON CO.
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
REF-SSINS-6820 4204N, IEB-81-01, IEB-81-1, NUDOCS 8206220377
Download: ML20054G879 (4)

Text

i .

C N Commonwealth Edison

) One First Nitiord PPz2, Cgo, minois O Addrzss Riply 12 Past Offica Box 767 Chicago, Illinois 60690 Jun e 15, 1982 Mr. James G. Keppler, Regional Administrator Directorate of Inspection and i Enforcement - Region III U.S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, IL 60137

Subject:

Dresden Station Units 2 and 3 Quad Cities Station Units 1 and 2 Final Response to I.E.Bulletin 81-01, Rev.1, Surveillance o f Mechanical Snubbers NRC Docket Nos. 50-237/249 and 50-254/265 References (a): J. G. Keppler letter to Cordell Reed dated March 4, 1981.

(b): T. J. Rausch letter to J. G. Keppler dated March 27, 1981.

(c): E. D. Swartz letter to J. G. Kepple r dated June 9, 1981.

! (d): E. D. Swartz letter to J. G. Keppler j dated January 14, 1982.

(e): J. D. Hegner letter to L. DelGeo rg e dated April 28, 1982.

Dear Mr. Keppler:

Reference (b) provided the Commonwealth Edison Company schedule for testing and inspection of mechanical snubbers installed on safety-related systems at our Dresden and Quad Cities Stations in accordance with Reference (a) requirements. Acco rdingly , References (c) and (d) provided the results of the inspections performed for '

our Dresden Station Unit 2 and Quad Cities Station Unit 2, i respectively. The attachment to this letter provides our final j

response for Dresden Station Unit 3.

! Reference (e) amended the Dresden and Quad Cities Stations Technical Specifications ( Amendments 70, 62, 76 and 70 to OPR-19, 25, 29, and 30, respectively) to indicate visual inspection and functional test requirements for safety-related mechanical snub-Ders. As a result, the Senior Resident NRC Inspector at our Quad Cities Station was consulted with as to whether or not compliance with Bulletin 81-01 requirements for our Quad Cities Station Unit 1 l would still be requireu iei vic. or these recently issued Technical Specification Amendments. The Senior Resident Inspector informed us that no further action is necessary on Bulletin 81-01. This was 8206220377 820615 JUN 17 N y 7 /!

, PDR ADOCK 05000237

• PDR -jhijnf7 l _ _ _ - _

I

! 3. G. Keppler June 15, 1982 based upon his conversations with Mr. I. T. Yin o f your office on May 12, 1982. Therefore, contrary to our commitments made in Re ference (b), the Quad Cities Station Unit 1 safety-related mechanical snubbers will nut be tested per I.E.Bulletin 81-01 requirements during the upcoming Fall,1982 refueling outage, but rather testing and inspections will be performed in accordance with the new Technical Specification requirements.

Based upon the above and the attachment to this letter, we believe the Bulletin 81-01 submittal requirements are now complete for our Dresden and Quad Cities Stations.

To the best of my knowledge and belief, the statements con-tained herein and in the attachment are true and correct. In some respects these statements are not based upon my personal knowledge but upon information furnished by other Commonwealth Edison employees. Such information has been reviewed in accordance with Company practice and I believe it to be reliable.

Please address any questions that you or your staf f may have concerning this matter to this office.

Very truly yo s

f. -.

7 - --

E. Douglas Swart Nuclea r Licensing Adminis trato r 1m cc: Director of NRC O f fice o f Inspection and Enf.

Washington, D.C. 20555 Region III Inspector - Dresden Region III Inspector - Quad Cities Roby B. Bevan - ORB-2 Jo seph D. Hegner - ORB 2 SUBSCRIBED AND SWORN to before me this /63m6 day l of [1v-w p , , 1982. '

Notary Public 4204N

s ATTACHMENT COMMONWEALTH EDISON COMPANY Dresden Station Unit 3 - Response to I.E.Bulletin 81-01, Revision 1, Item #4.

Dresden Station has performed the visual examination and functional testing of the installed safety related mechanical snub-bers on Unit 3 during the recent refueling outage. No abnormalities were discovered during these visual examinations.

The visual examination was conducted in the following man-ner. The inspection consisted of a check on the cold piston setting (indicating abnormal pipe movement), an investigation for possible visible damage of the snubbers and its attachments indicating an inoperable snubber, and an inspection of the structural attachments and piping for visual damage due to snubber failure.

The functional test consisted of a verification of freedom of movement by taking the snubbers and applying sufficient force to fully stroke the snubbers in both compression and tension modes.

The snubbers were not allowed to bottom out, thus preventing possible damage to the internals and ensuring that snubber integrity was maintained during the test.

There was one mechanical snubber #23, in the reactor clean-up system, that was found to be questionable during its functional testing. The questionable snubber was sent to Wyle Lab for full load testing. As a result of full load testing, the snubber was found inoperable and DVR 12-3-82-18 /R082-16 wa s written. Consultation with the vendor has revealed that the snubber probably failed due to overloading from a one time shock load. The snubber has been replaced with a new hydraulic snubber (HSSA-10) .

The Station is evaluating possible design changes to mitigate the chance of future failures.

The results of the visual inspection and functional testing indicate that all the mechanical snubbers were operational except snubber #23.

The attached table lists the number o f snubbers inspected, their manufacturer, model number, and size as required by Item Ab.

4204N

DJS LTR: 82-603 ATTTCtDSIT l

Manufacturer Model No. Size Nu:nber Status at Time of Functional Test Pacific Scientific Co. PSA-10 15 Kips 10 Unit 3: Have been installed inside drywll Pacific Scientific Co. PSA-10 15 Kips 4 Unit 3: Ranoved fran drywell per IEB 79-14 Pacific Scientific Co. PSA-35 50 Kips 16 Unit 3: Have been installed inside dr}wll l

l Pacific Scientific Co. PSA-35 50 Kips 2 Unit 3: Removed fran drywell per IEB 79-14 Pacific Scientific Co. PSA-10 15 Kips 11 Unit 3: Prior to installation in dr3wll for SRV modification Pacific Scientific Co. PSA-35 50 Kips 1 Unit 3: Prior to installation in drlwll for IEB 79-14 Pacific Scientific Co. PSA-10 15 Kips 2 Unit 3: Prior to installation in drymll for IEB 79-14 Pacific Scientific Co. PSA-h 0.35 Kips 6 Unit 3: Prior to installation for SDV nodification Pacific Scientific Co. PSA-5 0.65 Kips 1 Unit 3: Prior to installation for SDV modification Pacific Scientific Co. PSA-1 1.5 Kips 7 Unit 3: Prior to installation for SDV modification Pacific Scientific Co. PSA-10 15 Kips 2 Unit 3: Prior to installation for SDV modification

_ _ _ _ _ _ _ -