Safety Relief Valve Logic Setpoints

Question 1

What are the safety setpoints?

Answer 1

1) 1190 psig. 2) 1180 psig. 3) 1165 psig.

Question 2

Which SRVs are effected by LLS logic?

Answer 2

B21-F051D, B21-F051C, B21-F051G, and three other SRVs.

Question 3

How does LLS effect B21-F051D?

Answer 3

The relief setpoint for B21-F051D is normally 1103 psig with a closure pressure of 1003 psig. When LLS is armed the relief pressure for B21-F051D becomes 1033 psig with a closure pressure of 926 psig.

Question 4

How does LLS effect B21-F051C?

Answer 4

The relief setpoint for B21-F051C is normally 1113 psig with a closure pressure of 1013 psig. When LLS is armed the relief pressure for B21-F051C becomes 1073 psig with a closure pressure of 936 psig.

Question 5

How does LLS effect B21-F051G and the three remaining SRVs?

Answer 5

The relief setpoint for B21-F051G and the three remaining SRVs are normally 1113 psig with a closure pressure of 1013 psig. When LLS is armed the relief pressure for all four SRVs remain 1113 psig with a closure pressure of 946 psig.

Question 6

How many SRVs are there total? How many in each Main Steam Line? What are their normal relief pressure/closure setpoints?

Answer 6

There are a total of 19 Safety Relief Valves. The number in each Main Steam Line is: A - 3, B - 6, C - 6, D - 4. The normal relief/closure setpoints are: 1 - 1103 psig, 9 - 1113 psig, 9 - 1123 psig. Closure setpoints are approximately 100 psig less than the relief setpoint.