Category:NRC Information Notice[Table view]The following query condition could not be considered due to this wiki's restrictions on query size or depth: <code> [[:Beaver Valley]] OR [[:Millstone]] OR [[:Hatch]] OR [[:Monticello]] OR [[:Calvert Cliffs]] OR [[:Dresden]] OR [[:Davis Besse]] OR [[:Peach Bottom]] OR [[:Browns Ferry]] OR [[:Salem]] OR [[:Oconee]] OR [[:Mcguire]] OR [[:Nine Mile Point]] OR [[:Palisades]] OR [[:Palo Verde]] OR [[:Perry]] OR [[:Indian Point]] OR [[:Fermi]] OR [[:Kewaunee]] OR [[:Catawba]] OR [[:Harris]] OR [[:Wolf Creek]] OR [[:Saint Lucie]] OR [[:Point Beach]] OR [[:Oyster Creek]] OR [[:Watts Bar]] OR [[:Hope Creek]] OR [[:Grand Gulf]] OR [[:Cooper]] OR [[:Sequoyah]] OR [[:Byron]] OR [[:Pilgrim]] OR [[:Arkansas Nuclear]] OR [[:Braidwood]] OR [[:Susquehanna]] OR [[:Summer]] OR [[:Prairie Island]] OR [[:Columbia]] OR [[:Seabrook]] OR [[:Brunswick]] OR [[:Surry]] OR [[:Limerick]] OR [[:North Anna]] OR [[:Turkey Point]] OR [[:River Bend]] OR [[:Vermont Yankee]] OR [[:Crystal River]] OR [[:Haddam Neck]] OR [[:Ginna]] OR [[:Diablo Canyon]] OR [[:Callaway]] OR [[:Vogtle]] OR [[:Waterford]] OR [[:Duane Arnold]] OR [[:Farley]] OR [[:Robinson]] OR [[:Clinton]] OR [[:South Texas]] OR [[:San Onofre]] OR [[:Cook]] OR [[:Comanche Peak]] OR [[:Yankee Rowe]] OR [[:Maine Yankee]] OR [[:Quad Cities]] OR [[:Humboldt Bay]] OR [[:La Crosse]] OR [[:Big Rock Point]] OR [[:Rancho Seco]] OR [[:Zion]] OR [[:Midland]] OR [[:Bellefonte]] OR [[:Fort Calhoun]] OR [[:FitzPatrick]] OR [[:McGuire]] OR [[:LaSalle]] OR [[:Fort Saint Vrain]] OR [[:Shoreham]] OR [[:Satsop]] OR [[:Trojan]] OR [[:Atlantic Nuclear Power Plant]] OR [[:Crane]] </code>.
All holders of operating licenses or construction permits for nuclear power
reactors.
Purpose
This information notice is intended to alert addressees to potential problems
resulting from using the wrong flow and pressure drop relationship in estab- lishing adequate flow of essential service water to room coolers for engineered
safety-feature systems and from failing to establish or maintain balanced flows
in essential service water systems. It is expected that recipients will review
the information for applicability to their facilities and consider actions, as
appropriate, to avoid similar problems. However, suggestions contained in this
information notice do not constitute NRC requirements; therefore, no specific
action or written response is required.
Description of Circumstances
On March 9, 1990, the reactor at the Clinton Power Station was in cold shutdown, and the licensee was taking action to implement the recommendations contained
Equipment." The licensee discovered that the flow of essential service water
being supplied to several room coolers serving safety-related equipment was
approximately half of the design flow. The safety-related equipment included
components in the high-pressure and low-pressure core spray systems, the low- pressure injection system, the residual heat removal system, the standby gas
treatment system, the combustible gas control system, and the nuclear protection
system.
After discovering the problem, the licensee declared these systems to
be inoperable. The room coolers were supplied to the Clinton Power Station by
American Air Filter, a subsidiary of Snyder General Corporation.
Before initial operation of the Clinton Power Station, the licensee obtained
the relationship of the flow and pressure drop on the water side of the room
coolers from the supplier.
Plant personnel adjusted valving to establish the
pressure drop across each room cooler which would provide the design flow.
Plant personnel did not actually measure the flow to each room cooler.
IN 90-26 April 24, 1990 On March 9, 1990, the licensee discovered that the relationship between flow
and pressure drop for the room coolers was wrong and that flows of essential
also found that the flows of essential service water to several other coolers
and heat exchangers were too low.
To balance the flow of essential service water through the system, plant
personnel measured the flow using qualified instrumentation and adjusted
flows to the room coolers according to these measurements. In some instances, the adjusted flows to specific components were somewhat less than design flows.
However, the licensee is performing analyses to determine whether these flows
American Air Filter has supplied room coolers to approximately 50 nuclear
power plants including the Clinton Power Station.
The room coolers consist
of bundles of folded tubes with supply and return headers at the ends of the
tubes. American Air Filter supplies the room coolers either with or without
pairs of cleanout plugs at the bends in the tubes. At design flow, room
coolers with cleanout plugs have a significantly greater pressure drop across
the tube bundle than room coolers without cleanout plugs.
On April 3, 1990, Illinois Power Company, licensee for the Clinton Power
Station, stated in a report submitted to NRC under 10 CFR 21.21 that pressure
drop data provided by American Air Filter for 22 of 23 room coolers was incor- rect. Twenty-two room coolers had cleanout plugs while the 23rd room cooler
did not.
On April 5, 1990, Illinois Power Company submitted a licensee event
report which indicated that actual flows for the room coolers with cleanout
plugs ranged from 10 percent to 80 percent less than the design flows.
The licensee event report also indicated that 7 of 25 cooling components pro- vided by vendors other than American Air Filter and connected to the essential
service water system had flows that were less than the design flows.
For these
cooling components, actual flows ranged from 2 percent to 42 percent less than
exchangers supplied by General Electric Company, two RHR pump seal coolers sup- plied by Byron Jackson, a switchgear heat removal condenser supplied by Carrier
