Gland Seal Steam System

Question 1

Purpose of gland seal steam system

Answer 1

Purpose
Prevent the leakage of air into and steam leakage out of the main turbine and MFW pump turbine rotor shafts.
Accepts leakoff steam from turbine driven feed pumps and main turbine stop, governor control, reheat and intercept valve stems.

Question 2

At ____% the HP turbine is self sealing.

Answer 2

15%

Question 3

GS002 is the ______, fails ____ on loss of IA, and the main header is protected by a ____ and a _____.

Answer 3

GS header pressure regulator
Open
500# rupture disc and a 440# relief

Question 4

Purpose of Gland Steam Spillover Valve _GS023

Answer 4

Removes excess steam pressure from gland steam supply header

Question 5

Each LP turbine has its own fail ____ gland seal steam reg valve that maintains ____ psig.

Answer 5

open
1.3 psig

Question 6

What are the pressure setpoints for the following gland sealing steam regulators:
a. High pressure turbine?
b. Low pressure turbine?
c. Feedwater pump turbine?
d. Spillover AOV (_GS023)

Answer 6

a. 1.3 psig
b. 1.3 psig
c. 1.75 psig
d. 3.25 psig

Question 7

Which regulators have motor operated isolation and bypass valves?

Answer 7

Gland sealing steam supply header regulator, and spillover regulator valve

Question 8

If GS002 fails open, control gland seal pressure by ______.

Answer 8

Throttling bypass