Week 4 Flashcards
What does a pressurised water reactor contain?
Fuel plates which house U235
Hafnium control rods
Pressurised water
How is the rate of energy controlled and who controls it?
By raising or lowering control rods, operated by RPO
What are the types of SCRAM
Automatic Scram
Manual Scram
Partial Scram (From lowering group 3)
Full Scram (All 4 groups lowered)
Name the four plant states?
A
H
B
C
Plant State A
At least ONE condition met
Reactor may or may not be critical
More than one control rod is energised
Primary coolant pressure above 35 bar
Primary temp above 168C
Plant State H
ALL conditions met
Reactor is shut down with no more than ONE control rod energised
Primary coolant below 35 Bar
Primary coolant temp 93C - 168C
Plant state B
All conditions met
Reactor is shut down with no more than one control rod energised
Primary coolant pressure below 35
Primary coolant temp below 93C
Plant State C
ALL conditions met
Reactor is shut down and all CRDM’s are defused
Primary coolant pressure is below 35
Primary coolant temp is below 93C
What are the primary and secondary containment boundaries?
Primary: Hull surrounding reactor compartment RSC and Tunnel
Secondary:
Minimum - pressure bull between 26 and 88 bulkhead
Maximum - entire pressure hull
Function of nuclear steam raising plant (NSRP)?
Produce high-quality steam using heat from the fission produced in PWR
Components of NSRP?
Reactor pressure vessel
Fuel
Control rods
Control and drive motors (CRDM)
Primary circuit
Main cooling pumps (MCPs)
Steam generators
Pressuriser
How are the crew protected from radiological hazards?
Time
Distance
Shielding
As low as reasonably practicable
Hazards associated with steam systems?
Scalding
Burning
Potential lagging fires
Key operating parameters of the primary systems?
Pressure
Flow
Temperature
The 6 watch keepers for the primary/secondary system?
MRS
RPO
EPO
MMSS
METOW
MMSWK