b.
Thermometer: Bi-metal dial type with separable socket, 125 mm 5
inch dial, 10 to 149 degrees C 50 to 300 degrees F range.
c.
Zero to 172 kPa (gage) Zero to 25 psig range.
d.
Internal baffles and pipes:
As detailed.
2.14.10.2
Controls
Provide a self operating regulator to control the flow of cooling water to
the tank. Regulator shall include a 20 mm 3/4 inch screwed bronze body
with stainless steel trim, reverse acting actuator for cooling, capillary
tubing and a union connection bulb with a stainless steel well.
Control
setting shall be 60 degrees C 140 degrees F with a minimum Cv of [_____].
2.14.11
Continuous Boiler Blowdown System
Provide a complete automatic continuous boiler blowdown system, in
accordance with NBBPVI NB-27, which shall include a controller/programmer
unit and flow assembly for each boiler, plus a continuous blowoff heat
exchanger, flash tank and boiler water sample cooler.
2.14.11.1
Automatic Blowdown Controller
Intermittent type boiler blowdown system rated for not less than 1724 kPa
(gage) 250 psig steam pressure.
a.
Flow assembly: Include a 25 mm one inch ball valve with 316
stainless steel ball and stem and stainless steel electrode
assembly.
b.
Controller/programmer: Include a conductivity meter with zero to
6000 micromhos range, valve open/closed indicators and manual/auto
control switch. Cycle interval and sample duration shall both be
adjustable over a wide range. Mount units at the operating floor
near the boiler front.
c.
Accessories and connections:
(1) Continuous blowdown connection: At each boiler, provide a
gate valve and extend piping to header at flash tank.
(2) Header connections: Provide with a tee with valved sampling
connection. Provide a 20 mm 3/4 inch, three globe valve bypass
around each flow assembly.
(3) Common header: Provide from valved outlet connections on
flow assembly units, to connection on flash tank.
2.14.11.2
Flash Tank
ASME code stamped and constructed in accordance with the ASME BPVC SEC VIII
designed for [_____] kPa (gage) psig. Tank shall be [_____] mm inches in
diameter by [_____] mm inches long including heads.
a.
Provide tank with blowdown inlet, steam outlet, gage glass, float
operated outlet valve, relief valve, and inspection openings.
Tank shall have steel angle legs with plate feet for bolting to
floor and legs shall be of sufficient length so that bottom of
SECTION 15502N
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