ECA-3.1, 3.2, 3.3 (SGTR w/ loca)

Question 1

ECA-3.1

What are the major action catagories for SGTR w/loca, subcooled recovery?

Answer 1

• prep and initiate c/d to cold shutdown
• depressurize to refil Pzr
• reduce injection flow
• depressurize to minimize subcooling
• perform long term recovery actions

Question 2

ECA-3.1

What parameters determine if you do a subcooled recovery (ECA-3.1) or a saturated recovery (ECA-3.2) for a SGTR w/ LOCA?

Answer 2

Saturated

• L _{s/g (NR)} > 92 %

OR

• Lrwst < 62% AND
  
  • L_{recirc smp} < Expected (appx Y)

Subcooled

• if don’t meet conditions for saturated perform subcooled

Question 3

ECA-3.1

When you get to the step to secure an ECCS CCP (you have both running), if you do not meet the subcooling requirements to secure one pump, can you still secure the pump?

if so, why?

Answer 3

Yes, if WR T_h < 350 deg F you can still secure the CCP if you start one RHR pump and L_pzr > 17%

• 350 deg is the saturation temperature for the RHR pump at minimum recirculation flow
• starting RHR pump ensures subcooling is maitained once the high head eccs pumps are secured

Question 4

ECA-3.1/ 3.2

What is SI re-initiation criteria for SGTR w/ LOCA (ECA-3.1) subcooled recovery?

(ECA-3.2) saturated recovery?

Answer 4

• subcooling < 20 deg F
• L_pzr < 12% (or not maintained)
• CET rising
• RVLIS below table values (below top of core)

Question 5

ECA-3.2

What are the entry conditions for ECA-3.2 (SGTR w/ LOCA saturated recovery)?

Answer 5

• ECA-3.1, step 15
• FR-C.3, step 1

Question 6

ECA-3.1 / 3.2

What parameters do you look at to determine if you NEED ECCS flow in (ECA-3.1) subcooled recovery?

(ECA-3.2) saturated recovery?

Answer 6

• subcooling > 20 deg
• L_pzr > 12%
• RVLIS per table (above top of core)
• CET stable or lowering

Question 7

ECA-3.3

How is P_pzr controlled in SGTR w/o press cntrl?

Answer 7

• terminating SI
• placing letdown and normal charging in service
• controlling charging flow to compress or expand Pzr bubble

Question 8

ECA-3.3

What is SI termination criteria for SGTR w/o Press cntrl?

SI re-initaition criteria?

Answer 8

• subcooling >20 deg
• heat sink
• RVLIS > table (above top of core)
• subcooling < 20 deg
• RVLIS < top of core