extension neck, 150 mm 6 inch bulb length, 19 mm 3/4 inch IPS connection.
2.5.8.2
Pipeline Thermometers
Pipeline thermometers, as indicated, shall be similar to above with 65 mm
2-l/2 inch extension neck separable sockets, where accessible, and with
required capillary length where not accessible, for direct reading.
2.5.8.3
Flue Gas and Fuel Oil (if Oil-Fired) Thermometers
Temperature indicators shall be the vertical scale, moving pointer type, in
semiflush mounting dust-tight case, with curved translucent scales,
internally illuminated. The instrument scale graduations, figures, and
range shall suit the indicated service. The instrument shall employ a
diaphragm measuring element with linkage actuation of the indication
pointer. Thermal sensing element shall be the gas-filled bulb type with
spirally wound, bronze armored flexible copper connection tubing to the
instrument. Instrument accuracy shall be 2 percent of full scale range
with a sensitivity of 0.2 percent of full scale range.
2.5.8.4
Separable Sockets
At all points of recording, controlling, or integrating instrument
temperature bulb insertion, a stainless steel separable socket having a
screwed cover and attachment chain shall be installed adjacent to a
temperature bulb for insertion of a test thermometer.
2.5.9
Oxygen Analyzer
If oxygen compensation controls are furnished, an oxygen analyzer shall be
provided to indicate, record, and control the percentage of net excess
oxygen in, and the average temperature of the flue gas leaving, the boiler.
The oxygen analyzer shall be of the direct probe type utilizing an in situ
zirconium sensing element. The element shall be inserted directly into the
process flue gas stream and shall directly contact the process gases. The
sensing element shall be contained within a protective shield mounted to
the ductwork by an adapter plate, all furnished by the manufacturer. The
analyzer shall be equipped to allow daily automatic calibration check
without removing the analyzer from the process. That is, sample gases may
be injected directly on the sensing element while the analyzer is in the
process. The analyzer shall include any temperature compensation of
control required. The output signal range shall be 4 to 20 mA dc and shall
represent 0 to 10 percent as a linear function.
2.5.10
Flue Gas Opacity Monitor
A flue gas monitoring system shall provide continuous measurement,
indication, and recording of smoke opacity from each boiler. The stack
units shall include a light source and a light detecting or receiving unit
mounted in the stack or main breeching, as recommended by the manufacturer.
The control or transmitter unit shall have electronic solid-state
circuitry and meter or digital type indicator, and provide an output signal
for 0 to 100 percent opacity. In addition, the control unit shall have
calibration and alarm adjustments for compliance with Federal, State, and
local environmental regulations. The control or transmitter unit and
recorder shall have dust-tight metal enclosure. A purging air system shall
be provided to clean light source lens and light detector lens. The
control unit shall have adjustable alarm output contacts for various smoke
densities.
SECTION 15555A
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