ML20235F949

Ro:On 720404,while Reactor in Shutdown Mode,Damaged Pipe Restraint Reported to Operating Engineer on Tie Between RHR Removal Sys & Fuel Pool Cooling Sys.Caused by Improper Venting W/Resultant Water Hammer.Pipe Hangers Repaired

ML20235F949
Person / Time
Site:	Quad Cities, 05000000
Issue date:	04/11/1972
From:	Palmer F COMMONWEALTH EDISON CO.
To:	Morris P US ATOMIC ENERGY COMMISSION (AEC)
Shared Package
ML20235B311	List: IA-87-111, Submits Rept on Plant,As Discussed in ACRS 150th Meeting on 721012-14.Listed Items Can Be Resolved During Const & Facility Can Be Constructed W/Reasonable Assurance for Operation W/O Undue Risk to Public Safety IR 05000254/1972009 IR 05000358/1972003 IR 05000358/1973001 IR 05000358/1973002 IR 05000358/1973003 IR 05000358/1973005 IR 05000358/1973006 IR 05000358/1973007 IR 05000358/1974001 IR 05000358/1974002 IR 05000358/1974003 IR 05000358/1975004 ML20235B308 ML20235B364 ML20235B401 ML20235B405 ML20235B424 ML20235B456 ML20235B461 ML20235B465 ML20235B477 ML20235B488 ML20235B507 ML20235B552 ML20235B582 ML20235B585 ML20235B588 ML20235B605 ML20235B618 ML20235B623 ML20235B649 ML20235B656 ML20235B662 ML20235B670 ML20235B679 ML20235B683 ML20235B687 ML20235B702 ML20235B708 ML20235B713 ML20235B714 ML20235B718 ML20235B720 ML20235B730 ML20235B734 ML20235B748 ML20235B754 ML20235B762 ML20235B764 ... further results
References
FOIA-87-111 NUDOCS 8709290378
Download: ML20235F949 (2)

Text

_ _ _

i 1

D. 4

,p FAP-7?-84 hoguistory Filo Cy.

.309 454 2241 I h

Commonwealth Edison Company QU A D CITIES N U CL E A R PO WE R S T A TIO N Addrew Reply rou POST OFFICE DOX 216

• CORDOYA, iWNOl3 61242 {

l l A i Ar ril 11, 19'/2 & k

• /IOi a&<' I 4/yg,s

Orig  :

Dr. Peter A. Morris, Director Division of Reactor Licensing U. S. Atomic Energy Commission

( "d i

Washington, D. C. 20545 gs f) i NL % f$ -

Subject:

)

License DPR Quad-Cities Nuclear Power Staticin Unit #1 Section 1.0A4 and Section  !

1 6.682 of the Technical Specification

Dear Dr. Morris:

This is to report a condition relating to the operation of Quad-Cities Nuclear Power Station in which,  ;

during a routine inspection, seismic restraints and i pipe hangers on the residual heat removal system were found to be damaged.

Description -

On Tuesday, April 4,1972, at approximately 10:00 a.m. while the reactor was in the shutdown mode, a damaged pipe restraint was reported to the Unit 1-Operating Engineer. The restraint is located on line 1-1086-6" at 595' elevation, line 1-1096-6" the tie between the residual heat removal system (RHRS) and the fuel pool cooling system. Visual inspection of the RHRS  !

system revealed the following:

1) 1 - Seismic restraint on line 1-1009- damaged.

2) 2 - Spring hanger bottomed on line 1-1009-

3) Grout chipped on seismic restraint on line 1-1009

4) MO-1-1001-23B would not open electrically. 1 l

i

5) 2 - Seismic restraints damaged on line 1-1086

6) 4 - Hangers . damaged on li

\

s i* gg1S net W

I

% a lEn p a-c -q 8709290378 870921 p PDR FOIA

'fi% h

^

I'N MENZB7-111 PDR rJ

1

' s. ~ . ,

Dr. Peter d. Morris April 11, 1972 Cause - The cause of the incident is believed to be improper venting with the resultant water hammer. The l filling and venting procedure requires use of the jockey i pump as a water supply and an operator venting from the systems piping high points until a solid water flow is I

observed. The venting at high points only leaves several ,

possible points for air accumulation as follows:

Upstream from all four discharge check valves; and the tie line to the fuel pool cooling system. When the "A" RHR pump was started on Sunday, April 2,1972 for a modification test a noise was reported by an engineering i assistant in the technical staff working in the area, but no damage was noted at the time. ,

Analysis - Piping specialists from Sargent and Lundy were called to the station to evaluate the damage and to assist in directing the repair. After walking the system and measuring displacements, a computer analysis was performed. The results indicated that no piping or welds were overstressed. Three welds that were in the highest stress area were dye checked with no defects observed.

The damage was caused by water hammer. The system was in an operable condition and could have performed its intended function.

The motor operated valve MO-1-1001-233 containment spray failed to open electrically because of mechanical failure of the motor housing which caused the brake to engage. The valve could be operated manually, Repair and Corrective Action - Seismic restraints and p!pe hangere were repaired under the direction of the General Electric Company following approval procedures. The filling .

and venting procedure was altered so as to use the condensate transfer system as a water supply for filling. The -

condensate transfe~ system provides a larger flow and higher ,

pressure than the jockey system that was used in the old ~

procedure. Following the repair the new filling and venting procedure was used and the system tested with men located

• at all RHRS piping areas. The system was started with no signs of any water hammer. The motor operated valve MO-1001-23B was repaired and tested satisfactorily. -

Very truly yours , ,

COMMONWE ALTH EDISON COMPANY Quad-Cities Nuclea r Power Station W '

F. A. Palmer Superintendent ,

FAP/zm

- _ _ _ - _ __ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ - . _ _ _ - _ _ _ _ _ _ _ _ _ _. __ __. _ _ _ _ _ _ _