RCP Seal Injection, Bleedoff, & Chem Add Flashcards
What is the purpose of the filters downstream of the RCP seal injection HX?
2 filters in parallel, 1 in service at a time to prevent seal damage
What protects the RCP seals from over temperature or under temperature?
A valve downstream of the seal injection HX will close if the temperature is too high or too low.
Where does the controlled bleed off from RCP seals go?
To the VCT. If the valve is isolated to the VCT, water can go to the RDT via a relief valve.
How is the RCP bleed off and seal injection subsystem normally operated?
Automatic control
What components make up the chem add unit?
Chem add tank, outlet strainer, and a positive displacement pump all located in the “B” charging pump valve room.
Where are chemicals injected into the charging header at?
Just upstream of the RHX.
What chemicals are added to the primary and why?
A) lithium - raise low pH induced by boric acid
B) hydrazine - added for O2 control when RCS temp is <250F
C) hydrogen peroxide - cause crud burst pre-outage for clean up
Where does water for the chem add tank come from?
Reactor makeup water
What is the max capacity of the chem add pump?
25 GPH
Why is hydrogen peroxide added to the primary?
Added during plant shutdown to cause a crud burst and reduce RCS activity and dose
