Low Pressure Steam Control

b.

Air Operated Regulating Valves: Provide air operated control

valves for both the condensate and makeup water lines. Valves

shall have Class 125 or Class 150 rating with iron or semi-steel

bodies and 316 stainless steel internals. Provide condensate

valve which fails open on loss of air and makeup water valve with

an air lock mounted on valve diaphragm to hold valve in last

position on loss of air. Design valves for the following

conditions:

Condensate

Makeup Water

Valve size

[_____] mm

Capacity

[_____] L/s

Maximum pressure drop

at above capacity

[_____] kPa (gage) [_____] kPa (gage)

Available pressure

[_____] kPa (gage) [_____] kPa (gage)

Minimum Cv at 100

percent open

[_____]

Condensate

Makeup Water

Valve size

[_____] inch

Capacity

[_____] gpm

Maximum pressure drop

at above capacity

[_____] psig

Available pressure

[_____] psig

Minimum Cv at 100

percent open

[_____]

2.14.2.9

Low Pressure Steam Control

Provide an automatic control system to control steam to the deaerating

heater. Maintain steam pressure in the heater by modulating a pressure

reducing valve in the steam supply line. Control shall be local and remote

from the control panel.

a.

Controller: Adjustable proportional band, 0 to 103 kPa (gage) 15

psig brass bellows for input signal, and 20 to 103 kPa (gage) 3 to

15 psig output air pressure range, pilot controller complete with

air set (valve, filter, drier and pressure regulator) mounted on

control valve yoke.

b.

Pressure Reducing Station Control Valve: Provide a [_____] mm inch

air operated pressure reducing valve with proper internals to

pass a flow of [_____] kg per second pounds per hour of steam.

Steam at the valve inlet shall be [_____] kPa (gage) psig

saturated, and outlet shall be controlled at [_____] kPa (gage)

psig. Minimum steam flow shall be approximately [_____] kg per

second pounds per hour. Minimum valve Cv shall be [_____] at 100

percent open. Valve shall be Class 250 or Class 300 flanged, iron

SECTION 15501N

Page 124