boiler capacity per minute with boiler water dissolved solids concentration
at approximately 3,500 ppm and total alkalinity not in excess of 700 ppm.
2.3.3
Construction
Boiler shall be built and stamped in accordance with ASME BPVC SEC I and as
specified.
2.3.4
Identification
Boiler shall be stamped as follows:
a.
Maximum capacity in MW Btu/Hr.
b.
Maximum allowable working pressure.
c.
Radiant heating area.
d.
e.
Furnace volume.
2.3.5
Watertube, Packaged Type Steam Boiler
Boiler shall be shop assembled type with either 2 or 3 drums and water
cooled furnace roof, floor, front, rear and side walls. The furnace side
and rear walls shall be completely suitable for pressurized firing. Boiler
faces shall be arranged to give maximum cooling effect to furnace
refractories. Furnace waterwall tubes shall enter steam drum below the
normal operating drum level. Tube inspection ports shall be provided in
furnace to boiler division wall, along both the steam and lower drums.
Furnace shall be sized for complete combustion of fuel in the furnace with
no flame impingement on the water-cooled surfaces and no combustion in the
convection area. The furnace heat release rate, based on fuel analysis and
required fuel input, shall not exceed [_____] gigajoules/hr. cubic meter
Btu/hr. per cubic foot of furnace volume. Furnace heating surface shall
not be less than [_____] square meters square feet on a flat protected area.
2.3.5.1
Drum
a.
Drums shall extend beyond the entire length of furnace setting.
Drum shall be fabricated of steel plate, welded in accordance with
ASME BPVC SEC I, including stress relieving and X-raying of welded
seams. Steam drum shall be provided with steam separators and
drum internals required to maintain the specified steam moisture
content, and provisions for maintenance. Necessary baffling shall
be provided to separate steam from water in the drum and to
maintain stable water level under a fluctuating load. Variations
in normal water level shall not exceed boiler manufacturer's
recommendations as approved during the shop drawing submittal
stage with an increasing load change of 10 percent of boiler
capacity per minute. The steam drum diameter shall not be less
than the following:
1. 915 mm 36 inch (steam flow of 5,455 to 31,800 kg/hr 12,000 to
70,000 pounds/hr).
2. 1,070 mm 42 inch (steam flow of 31,800 to 45,450 kg/hr 70,000
to 100,000 pounds/hr).
SECTION 15561A
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