storage section. Gage glasses shall not be greater than 600 mm 24 inches
center-to-center. Provide gage glasses complete with [chain operated] ball
check shutoff and drain cock valves and safety shield.
2.9.2.12
Alarms
Provide high and low water level alarms for storage tank as follows:
a.
High Water Level Alarm: Switch with stainless steel float and
trim. Locate switch to close circuit when water level rises to 25
mm one inch below overflow level of storage tank.
b.
Low Water Level Alarm: Switch with stainless steel float and
trim. Locate switch to close circuit when water level falls to
[_____] meters feet [_____] mm inches above bottom of storage tank.
c.
Coordination:
Coordinate alarms with annunciator panel as
indicated.
2.9.2.13
Multiport Back Pressure Relief Valve
**************************************************************************
NOTE: Use multiport valve on systems where
deaerating heater will be subject to occasionally
overpressuring.
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Provide valve capable of relieving not less than [_____] kg per second
pounds per hour of steam with not more than a [_____] kPa (gage) psig
pressure rise when set at [_____] kPa (gage) psig initial operating
pressure. Set pressure shall be fully adjustable by means of an external
handwheel or chain operator for a range of zero to 172 kPa (gage) 25 psig.
Locate on low pressure steam header manifold for the deaerating heater.
Valve shall be multiport vapor cushion type rated for operating
temperatures up to but not greater than 149 degrees C 300 degrees F with
Class 125 cast iron body, bronze trim and carbon steel springs.
2.9.2.14
Exhaust Head
FS A-A-50494, Type [I (cast iron)] [II (fabricated steel plate)] of [_____]
mm inch size with [_____] mm inch diameter drain, and a capacity of [_____]
kg per second pounds per hour of steam at [_____] kPa (gage) psig.
2.9.3
Boiler Feed Pumps
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NOTE: Use this paragraph for centrifugal boiler
feed pumps. Use Style 1, horizontal split case
pumps in all sizes. Pump service requirements shall
include a minimum pump capacity of 125 percent of
boiler requirements at maximum load. Discharge head
must be sufficient to deliver water to the boiler at
a pressure 3 percent higher than the boiler safety
valves setting and up to 6 percent over the maximum
operating pressure of the boiler in accordance with
the ASME Boiler and Pressure Vessel Code.
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FS A-A-50562, Type II (boiler feed pump), Style 1 (horizontally split
SECTION 15511N
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