range suitable for the use encountered. Mercury shall not be used in
thermometers. Thermometer shall be a dial, 90 mm 3-1/2 inch diameter
chromium-plated case, remote bulb or direct bulb as required, with plus or
minus 1 degree C 2 degree F accuracy, and white face with black digits
graduated in 2 degree increments. Thermometers shall be installed so as to
be easily read from the operating floor.
2.9.15.2
Thermocouples
Thermocouples shall be suitable for continuous operation and control at
temperatures up to 1260 degrees C 2300 degrees F, accurate to 0.75 percent,
and shall be long enough to be inserted 150 mm 6 inches into the boiler.
Thermocouples conforming to ISA MC96.1, Type K shall be provided with an
adjustable flange and with a high-temperature metal alloy closed-end
protection tube suitable for inserting into the furnace without support of
the projecting end. One hundred feet of 16-gauge compensating lead wire
with a weatherproof braid shall be supplied for connecting the thermocouple
to the instrument. Installed unit shall indicate gas passage temperatures
and shall control combustion equipment operation. Temperature shall be
transmitted to the instrument in the control panel as shown.
2.9.15.3
Indicating, Recording Pyrometers
The instrument shall have a temperature range from minus 18 to plus 1316
degrees C 0 to 2400 degrees F, and shall be accurate to within plus or
minus 1/4 of 1 percent of the range. Temperature shall be indicated on a
large scale with prominent black letters on a white background and shall be
recorded by chart recorder. The instrument shall have automatic
cold-junction compensation. A simple means of pyrometer standardization
shall be provided. Instrument shall not be affected by vibration, dust, or
air currents when the door of the instrument is open. Lighting circuit for
110 volts ac shall be available.
2.9.16
Draft Indicator and Control
An indicator continuously showing pressure in the boiler shall be provided.
A separate draft-controlling instrument maintaining a constant balanced
(atmospheric) pressure in the boiler shall also be provided. Gauges shall
conform to ASME B40.100, Style 1 with a diaphragm or bellows actuating
system and a circular scale. Gauges shall have a zero adjustment screw and
a connection to atmosphere. Suitable shutoff cocks shall be provided.
Gauges shall be remote reading to the control panel and shall be installed
complete with all necessary piping between the gauges and the points at
which the drafts are measured. Gauge piping shall be copper tubing
conforming to ASTM B 68M ASTM B 68, Type K or L.
2.9.17
Pressure Gauges
Gauges shall be heavy-duty industrial type conforming to ASME B40.100, Type
I, Class 1 or 2, as applicable, style as required, suitable for specified
pressure or vacuum with minimum 115 mm 4-1/2 inch diameter dial, except as
otherwise specified. Pressure gauges shall be installed on the
low-pressure side of each pressure-reducing valve, on the suction and
discharge side of each pump, on inlets and outlets of heat exchangers, on
the feedwater heater, and where shown or required for proper operation.
Pressure gauge shall be installed on each boiler and shall have a [250 mm
10 inch] [300 mm 12 inch] dial face. Gauges shall be installed so as to be
accessible and easily read from the operating floor. Gauges shall be
equipped with integral or separate siphons, and pulsation dampeners and
SECTION 15846A
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