(1)
[_____] mm inch drain
(2)
[_____]
mm inch boiler feed recirculation ([_____] required)
(3)
25 mm One inch sampling
(4)
25 mm One inch chemical feed
(5)
[_____] mm inch for sight glass ([_____] sets required)
(6)
[_____] mm
inch for high and low level alarm switches
(7)
[_____]
mm
inch thermometer well
(8)
Vacuum breakers as required
(9)
[_____] mm
inch spare (capped)
(10)
[_____] mm
inch spare (flanged)
(11) [_____] mm
inch level transmitter and controller ([_____]
sets required)
(12)
Downcomer and equalizer as required
(13)
[_____] mm inch feedwater outlet
(14)
[_____]
mm inch overflow outlet with internal water seal
2.9.2.9
Level Control
Provide an automatic control system to control water level in the storage
tank, by modulating valves in makeup water lines. Condensate pump output
shall be controlled by level in condensate storage tank.
a.
Controllers: Provide external cage type air operated level
controllers for both the condensate and makeup water lines
complete with 40 mm 1 1/2 inch screwed connections, external cage,
and controller. Cage body shall be Class 125 cast iron
construction. Internal components including displacer, torque
tube, displacer rod, displacer rod driver and bearings shall be
316 stainless steel. Displacer shall be 350 mm 14 inches long.
Controller shall be direct acting with 20 to 103 kPa (gage) 3 to
15 psig range with proportional band adjustment. Locate
controller to maintain an operating level at 2/3-full point of
storage tank. Provide level controller with air pressure reducing
valve, filter, gages and isolating valves for float cage. Provide
unions on each side of float cage.
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:
SECTION 15511N
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