SH

Question 1

Screen House Function
(three things)

Answer 1

-Provide reliable supply of river water for Secondary Service, Nuke Service, Decay River, Reactor River, Fire Service, and Screen House Ventilation/Cooling
-Bar Rake and Screen system ensures river debris is removed prior to reaching pump suctions.
-River water pump lubrication system (RWPLS) provides river pump bearing lubrication and cooling under normal conditions.

Question 2

Three (3) Automatic Bar Rakes
(SR-S-2A/B/C)
Function, auto signals, interlock

Answer 2

Function: remove >1” debris
Auto signal: Tork timers @ 0700, 1500, and 2300 OR DP of 4” (A &C only)
Interlock: Slack cable event causes rake to STOP

Question 3

Three (3) Traveling Screens
(SR-S-3A/B/C)
Function

Answer 3

Moving screens downstream of bar rakes remove debris >3/8” square. Cleaned
by water jet spray directed down on screens during ascending run

Question 4

Three (3) Traveling Screens
(SR-S-3A/B/C)
Start Permissive

Answer 4

Start Permissives: Requires 67# screen wash pressure to start, will NOT run without SWPs

Question 5

Three (3) Traveling Screens
(SR-S-3A/B/C)
Auto Signals

Answer 5

Rake Starts, Tork timers @ 0300, 1100, and 1900 or DP of 4” (A & C only)

Question 6

Three (3) Traveling Screens
(SR-S-3A/B/C)
Speed Control

Answer 6

SLOW (2.5ft/min) speed in HAND, FAST (10ft/min) speed on high DP of 6”

Question 7

Screen Wash pumps (SW-P-1A/B)
Function

Answer 7

Provide high pressure water for cleaning screens and sluicing debris to trash pits.

Question 8

Screen Wash pumps (SW-P-1A/B)
Power Supply

Answer 8

1R 480V Bus/1T 480V Bus, 125 vital DC control power

Question 9

Screen Wash pumps (SW-P-1A/B)
Auto start/interlocks

Answer 9

Auto Start: screen/rake demand relays
Interlocks: First SW-P-1 taken out of PTL (placed in standby) is lead pump (will start first
on demand signal)

Question 10

Screen Wash pumps (SW-P-1A/B)
Trips

Answer 10

Load shed on ES and locked out by 27/86 w/ manual reset, Loss of DC Control Pwr

Question 11

Tech Specs from L&P for rake and screen

Answer 11

Rake and screens satisfy TS definition of auxiliary equipment needed for safety related TS river water pumps, OPERABILITY based on DP <6”

Question 12

Time limit on rake and screen continuous operation brings in alarm and indicates elevated river debris?

Answer 12

15 min rake and 20 min screen

Question 13

Screen Wash strainer (SW-S-1A/B)
Power supply

Answer 13

1A/1B SH ES MCC

Question 14

Screen Wash strainer (SW-S-1A/B)
Auto Signals

Answer 14

AUTO start with pump start, Backwash @ 9# with a 10# DP alarm

Question 15

Screen Wash strainer (SW-S-1A/B)
Interlocks

Answer 15

Strainer backwash valves OPEN on high DP and timer

Question 16

Two (2) River Water Lubrication Pumps (WT-P-33A/B)
Function

Answer 16

Provide clean filtered water (Domestic Water is backup) to river pumps
for bearing lubrication and flushing. Bearing temp < 155o
F @ >95# and >20gpm

Question 17

Two (2) River Water Lubrication Pumps (WT-P-33A/B)
Power supply

Answer 17

1A/1B ES SH MCC

Question 18

L&P for Screen House
2 main things

Answer 18

1.) Min lube water pump flow is 20 gpm for WT-P-33A/B protection
2.) If lube water is not available or if there is no packing leak off SW pumps can perform design function (self-lubricating)

Question 19

Abnormal system operation
River water low level for system failure and RX trip

Answer 19

RW system failure if river <277’

Trip RX at <271’

Question 20

Abnormal operation
What happens on failure of York Haven Dam

Answer 20

All river pumps retain suction