ML031530174

Engineering Change Screen

ML031530174
Person / Time
Site:	Davis Besse
Issue date:	05/29/2003
From:	First Energy Services
To:	Office of Nuclear Reactor Regulation
References
FOIA/PA-2003-0224
Download: ML031530174 (1)

Text

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I Page)'ofk ',6 NOP-CC-2003-04 Rev. 01 ENGINEERING CHANGE SCREEN CR-f 0 C) 8v 0 v2 l DS l PY 0 SAFETY-RELATED l 0 AUGMENTED 0 NON-SAFETY  :

ActivIty: Enlarge the outside chamfer on the faces of Reactor Coolant Engineering Change Request No.:

Pump P36-1 and P36-2 covers to provide for proper fit with the Pump 02-0805-00 Casing.

1. State the design function(s) of the structure. system or component.

Reactor Coolant System - The Reactor Coolant System performs the folloYing functions which are important to safe plant operation:

a. Transfers heat from the reactor core to the Steam Generator.

- The RCS transfers heat from the core to the Steam Generator during steady state operation and for any design transient without exceeding core thermal limits.

- The RCS removes decay heat from the core via redundant components and features using controls from inside or outside the control room.

- The RCS is designed to be capable of natural circulation cooldown from normal operating temperature and pressure to conditions that permit operation of the Decay Heat Rernoval System.

b. Forrns'a barrier against the release of reactor coolant and radioactive material to the environs.

c. Transfers heatfrom the reactorcore to containmentduring a lossofSteamGeneratorCooling with high RCS pressure uilizing MUIHPI Core Cooling. MU/HPI Core Cooling is not an original design capability but a post operational modification.

The function of the Reactor Coolant Pumps (RCPs) s to circulate water to and from each SG. The pumps provide the required forced cooling flow through the core for adequate heat removal during core power operation.

The ECR initiator states that while disassembled for maintenance, RCPs P36-1 and P36-2 were discovered to have a C. proviously undocumented recessed machine surface on the pump cases. This condition precluded proper case to cover fit-up and is the likely cause for gasket leakage at these joints. Therefore, this ECR is to ensure proper fit-up between the RCP cover and casing.

FlowServe, the pump manufacture. provided documentaion concurring with the fact that this condition may have been fixm original machining operations. FlowServe further states that enlarging the chamfer on the outside diameter of the cover face to 0.10' x 450 will ensure proper fit-up of this joint without compromise to any design attribute of the RCP's.

Additionally. this cleaning operation does not affect the pressure integrity function of the cover.

2. Slate the bounding technical requirements of the structure, system or component.

Thie bounding technical requirements of this Reactor Coolant Pump cover-to-casing joint is to provide a proper alignment and fit-up of these items to assure proper gasket compression.

3. Identify source documents for the above.

A) Design Drawinqs Vendor Drawing M-508-74. Reactor Coolant Pump Outline Drawing 81, System Des cription SD-039A Reactor Coolant System.

JUSTIFY INO" ANSiERS BELOW IF LOGIC IS NOT OBVIOUS.

SCREENING QUESTIONS YES NO C 1. VIould any interfacing organizations idenUfy a design function change? Basis for answer. O 0 This ECR ensures coverto-casing fit-up and does not represent a design functional change.

2. Vould the change impact any bounding tochnical requirements? 0 0 This ECR provides for proper fit-up of the cover-to-casing and therefore assures proper gasket cDmpression.

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