ML18219C195

Response to IE Circular No. 76-05. Re Action to Be Taken by Licensee for Items 1-3, Provide Information for Unit 1 & Request 60 Day Extension for Unit 2

ML18219C195
Person / Time
Site:	Cook
Issue date:	01/10/1977
From:	Dolan J American Electric Power Service Corp
To:	James Keppler NRC/RGN-III
References
INE-76-005
Download: ML18219C195 (13)

Text

1 1 AMERICAN ELECTRIC PC)WER Servi ce Corporation 2 Broaduay, Peto York, E. K I0004 (2I2) 422 4800 JOIIIIE.DOI hII Senior Esccnticc I tcc Prccidcnt Erginccring & eorurnction January 10, 1977 Donald C. Cook Nuclear Plant Unit Nos. 1 & 2 Docket No. 50-315 and No. 50-316 DPR No. 58 and CPPR No. 61 Nr. J. G. Keppler, Regional Director U'.S. Nuclear Regulatory Commission Office of Xnspection and Enforcement Region XXX 799 Roosevelt Road.

Glen Ellyn, Xllinois 60137

Dear 1:

r. Keppler

This letter is in response to your letter of October 8, 1976, whicn was received on October 10, 1976, and which transmitted XE Circular No. 76-05 "Hydraulic Shock and Sway Suppressoxs-Yiaintenance of Bleed and Loc'k-up Velocities on XTT Grinnell's Model Nos. Pig. 200 and Pig. 201, Catalog PH-74-R."

We hereby request a 60 day extension of time to respond to items 1, 2 and 3 for Unit No. 2 in the "Action to be taken by Licensee",,section of your letter. This additional time is required due to a delay in obtaining all the necessary information for Unit No. 2 snubbexs from XTT Grinnell.

The numbered paragraphs below axe in response to items 1, 2 and 3 for Unit No. 1 in" the "Action to be taken by Licensee" section .of your letter.

Our ovation's 200th Year g 9 76 Our CotrtIIttnJt's 70th, Year J,gf) 17 1977

4 1

Mx. J. G. Keppler January 10, 1977

'ITEN 1 a.

Only three snubbers axe curxently installed on safety-xelated systems in Unit, No. 1 having contxol valve serial numbers in the B-0001 through B-2000 range:

Snubber Control Valve Mark Number Serial Number Pi in S stem 1-GCCW-S-278 B-0021-Al-D71C Component Cooling tlatex 2-GMS-S-986 B-102 1-A3-D7 1C Main Steam 2-GMS-S-957 B-0646-A2-D7 lC Residual Heat Removal ITEM 1 b.

M-rk No. 1-GCCW-S-278: This defective snubber was zemoved from its installed position in the component, cooling water (CCN) system after having been discovered while performing a Technical Specification Surveillance Requirement. 4.7.8.1.3 inspection. At that time a request was made of ITT Gzinnell fox the original test date and test results, however, this information was not reason, when the snubber was given to ITT Grinnell available'ox'his in April, 1976 it was given an "as xeceived" test.

test was carried out on April 23, 1976 at ITT Gxinnell's This Narren, Ohio plant.

The xesults were: Locking Uelocity 2.6 in./min. tension 5.4 in./min. compression Bleed Velocity 1.4 in./min. tension

2. 1 in./min. compression The snubber was rebuilt the same day, then recalibrated and tested to the requirements of the AEPSC Specification DCC PM 402 QCN, Revision 2, Addendum C.

The results were: Locking Velocity 8.6 in./min. tension 8.6 in./min. compression Bleed Velocity 4. 0 in./min. tension 4.0 in./min. compression

4 Mr. J. G. Keppl r Januaxy 10, 1977 This snubber was re-installed in the CCN System on May 1,,1976 and there has been no problems encountered with the snubber since its xe-installation.

Mark Mo. 2-GMS-S-986: On May 28, 1976 during a routine operator inspection tour of the containment (which takes place during every shutdown) a snubber on the Main Steam System was founQ to be lea'king hydraulic fluid past its piston seal. Nhile this snubber was being removed from the system, snubber 986 (a new un-installed snubber originally purchased for Unit No. 2) was hand carried by aiz to XTT Grinnell. Xt was then recalibxateQ and tested to the required specifications.

The results were: Locking Velocity 8.0 in/min. tension 8.0 in./min. compression Bleed Velocity 4. 0 in./min. tension 4.0 in./min. compression Snubber 986 was returned to the plant and installeQ on the Main Steam System of Unit Ho. 1 on the same day. Since that time, there have been no problems associateQ with this snubber.

Mar'k No. 2-GNS-S-957: During a routine opezator inspection tour of the Residual Heat Removal (RHR) pump room outside of containment, in June, 1976, a snubber on the EMIR System was found to be leaking oil past a tom piston seal. On June 26, 1976, snubber 957 (a new un-installed snubber also purchaseQ for Unit. No. 2) was hand carried by aix to XTT Gzinnell's plant. Xt also was recalibrated and testeQ to the required specifications.

The results were: Locking Velocity 8.2 in./min. tension 8.0 in./min. compression H

Bleed Velocity 4.0 in./min. tension 4.0 in./min. compxession Snubber 957 was returneQ to the plant and installed on the RHR System of Unit No. 1 the same day. There has been no problem encountered with this snubber since its installation.

Hr . Z. G. Keppler january 10, 1977 There has been no regular or preventive maintenance of any kind performed on all of the above snubbers prior to or since they were recalibrated and tested by XTT Grinnell.

XTEM 1 c.

The current lock-up and bleed rates for the Unit No. 1 snubbers are defined in the AEPSC Specification DCC PM 402 QCN, Revision 2, Addendum C as follows:

"Para ra h 4.2.2 The lock-up velocity and bleed rate of the snubber unit shall be determined.

The piston lock-up velocity for all sizes shall be 8.0 in./min., + 2.0 in./min.

The bleed rate under rated load for all sizes, except 5" x 5" size, shall be 4.0 in./min., + 1.0 in./min. For the size 5" x 5" snubber, the bleed rate under

'rated load shall" be 2.5 in./min., + 1.0 in./min."

The American Electric Power Service Corporation specified the rates in the original construction/purchase specification.

The rates the snubbers were required to meet in the original specification DCC PM 402 QCN, Revision 1, dated ll/29/72 were as follows:

"para ra h 3.4.2 The snubber piston during operation. shall be free to move unrestricted in either direction, with the valves remaining fully open, for all fluid flow up to 0.25gpm.

Mhen the flow exceeds 0.25gpm and the valves close, the maximum piston rod dis-placement shall not, exceed 0.25 inches, in going from zero to full load. "

XTEM 1 d.

Xt is our intent. to rely primarily on recalibration of the snubbers with special test equipment recently purchased for the Donald C. Cook Nuclear Plant from ITT Grinnell for that specific purpose. Recalibration will be to 0'e require--

ments of the revision of specification DCC PM 402 QCN, in effect at the time of calibration. The current issue of this

Mr. J. G. Eeppler January 10, 1977 specification does not permit a bleed rate of less than 2.0 in./min., except for the size 5" x 5" snubber for which ITT Grinnell recommended the specification of 1.5 in./min. as the lower bound under rated load.

ITEN 2 Documentation defining the lock-up and bleed velocities for the three Unit Mo. 1 snubbers is available in the Donald C. Cook Quality Assurance "Master File",

the official repository for all QA/QC documentation.

XTHM 3 A plant maintenance procedure has not been written at this time. A number has been assigned (12 MHP 5021.001.028) in order to allow the proceduxe to be written foll'owing the January 1977 re ueling shutdown. The current.

guidelines utilized for repair and testing of snubbexs incorporate the provisions of various proceQuzes supplied .

by ITT Grinnell which include:

a. PIID 5434-1, a detailed procedure concerning the operation of the snubber test equipment, and the testing of snubbexs. This procedure has been reviewed anQ approved for use by AHPSC.

b. Tear-down and rebuild procedures for the replacement of seals in the cylinder assemblies of various manufacturers utilized by ITT Gxinnell in the snubbexs supplied for Unit Ho. l.

c. Replacement Instructions for Control Valve seals in the Control Valve Assembly.

will be used until a final plant procedure

'hese is written and approved.

Our course of action in the event that a snubber is found to be defective is dependent upon the nature of the Qefect. Ne have, in stock, certified ethylene propylene control valve thxead seals and seal kits for cylinders of various sizes and manufacture. Such seals can be replaceQ

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Mz. Z; G. Keppler January 10, 1977 C~

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through use of a Procedure Temporary Sheet and the appropriate XTT 'Grinnell teardown/rebuild. procedure. The snubber is then tested to the lock-up and bleed requirements of specification DCC PM 402 QCN, Revision 2, Addendum C. This testing is accomplished through the use of the special test equipment supplied by XTT Grinnell for the purpose of recalibration to meet the required specifications.

The Surveillance Test Procedure for the inspection of safety-related XTT Grinnell snubbezs, 12 MHP 4030.STP.004, in April 1976 had a paragraph in Step 7.2.2 which permitted

,tightening of control valve seal nuts to stop minor leakage.

The procedure stated that the valve screws must be maintained at their original settings. The result of Grinnell's "as-received." testing of Unit 1 snubbezs during the April/May, 1976 rebuild program indicated that extreme care would be necessary if ~an tightening of the valve seal nuts was attempted. Accordingly, a Temporary Change Sheet No. 1 was issued at that time to specification 12 MHP 4030.STP.004.

The Temporary Sheet stated:

"Do not tighten or otherwise move control valve seal nuts or adjustment screws as presently permitted in the third paragraph of Step 7.2.2."

The current specification 12 MHP 4030.STP.004, Revision 4 dated 1/3/77 has eliminated the provision for tightening the seal nuts.

At the present time, we do not have parts for the repair of locking and bleed valves. Ne have recently requested from XTT Grinnell a listing of control valve parts so that these items can also be stoc'ked. Xf' defective control valve assembly is encountered, we will either replace the entire snubbez with a spare unit, return the snubbez to ITT Gzinnell for repair, or purchase a replacement control valve assembly.

m Very truly your s,

p. /

ohn E. Dolan JED -mam Senior Executive Vice President Engineering and Construction cc: see next page

tI Mr. J. G. Keppler January l0, 1977 cc: Dr E. Volgenau, Director XGE, U.S.N.R.C.

G. Charnofi R. C. Callen P. N. Ste3cetee R. Nalsh R. J. Vollen R. W. Jurgensen Bridgman R. S. Hunter

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