g.
[Superheater heating surface in square meters square feet.]
2.2
BOILER DETAILS
2.2.1
Packaged Steam-Generating Units
a. Firebox Type (for Boiler Capacities Less Than 2.9 Mega watts 10,000,000
Btuh:) Units shall be furnished complete with coal burning equipment, [fly
ash collector,] brickwork, insulation with steel jacket, safety and
operating controls, forced- and induced-draft fans, low water cutoff and
alarm, and other required appurtenances. The unit shall be complete,
self-contained, fully automatic, and ready for service upon completion of
utility connections except that firing equipment, safety and operating
controls may be packaged separately from the boiler, fully assembled,
factory wired, and completely ready for field mounting. The firebox boiler
shall be of the watertube or firetube type in conformance with ASME BPVC
SEC I. Control panel shall be prewired and totally enclosed. Over-fire
air jets shall be provided for furnace turbulence. Positioning controls
shall be provided. [The boiler shall be equipped with soot blowers.]
b. Watertube, Waterwall Type (Boiler Capacities Over 2.9 Mega watts
10,000,000 Btuh:) Except as modified, the steam-generating unit shall
comply with the requirements of ASME BPVC SEC I. Steam generating unit
shall be furnished complete with stoker, [fly ash collector,] forced- and
induced-draft fans, control and instrument panel with limit and automatic
controls, soot blowers, over-fire air system feedwater regulator, low water
cutoff and alarm, feed piping and all other fittings, auxiliaries, and
appurtenances necessary for safe and efficient operation. The steam
generator shall be factory fabricated and [assembled on a steel foundation
or foundations] [top supported].
2.2.2
Watertube Boilers
Watertube type boilers shall be of the [site assembled] [shop assembled]
type with either two or three drums and arranged to suit the fuel burning
equipment specified. Boilers shall be capable of continuous operation at
the indicated capacity.
2.2.2.1
Drums
Drums shall be steel plate, fusion welded in conformance with ASME BPVC SEC
I, including stress relieving and x-raying of welded seams. The main steam
drums shall be of sufficient size to accommodate steam separators and drum
internals with provisions and space for accomplishment of maintenance.
Baffling shall be provided to separate the steam from the water in the drum
and to maintain a stable water level under a fluctuating load. Variations
in normal water level shall not exceed 50 mm 2 inches, with an increasing
load change of 20 percent of rated capacity per minute. Steam separators
shall be provided to deliver saturated steam with maximum specified
moisture content. Each drum shall have two 304.8 x 406.4 mm 12 x 16 inch
elliptical manholes, with the exception of the mud drum which shall have at
least one 304.8 x 406.4 mm 12 x 16 inch elliptical manhole. Each manhole
shall have cover, yoke, and gaskets.
2.2.2.2
Tubes
Tubes shall be not less than 50 mm 2 inches in diameter, shall be electric
welded or seamless steel, and shall be connected to the drums and headers
SECTION 15559A
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