manufacturer's recommendations.
3.1.1
Boiler
3.1.1.1
Installing Tubes In Headers
Tubes may be rolled into the headers provided the holes used for rolling
will not be blocked for access in the future by any item of equipment or
piping, provided under this contract. Otherwise, weld tubes into the
headers by use of stubs or socket welds. Stub end tubes may be welded into
headers in shop and tubes welded to same in field.
3.1.1.2
Installing Tubes In Drums
Before installing tubes, polish tube ends and tube seats in the drums to
bright metal using a No. 60 grit cloth grinding band driven on a pneumatic
or electric polishing motor. Do not polish these tubes until ready for
immediate installation. Install the tubes and hold in place with proper
width, hard maple wood spacers and by lapping the tubes in the tube sheet.
Lap tubes only enough to hold them in place for rolling. Check tube
stock on each end of the tube before rolling. Furnish 10 mm 3/8 inch stock
on each tube end with no deviation. When, after the tubes are rolled in
place, there remains more than 10 mm 3/8 inch stock due to extra length of
tube, excess shall be milled off to 10 mm 3/8 inch using a milling wheel
driven by a pneumatic or electric motor. At no time shall there be less
than 10 mm 3/8 inch stock between end of tube and nearest surface of
header. Tubes shall then be rolled with a bell roll of the proper size and
tension. Tubes shall not be rolled to excess. Drive bell roll by a
pneumatic or electric motor using a proper size mandrel pin.
At no time
will a manual operation of tube rolling be permitted. Lubricant for the
expanding operation shall be a water soluble compound.
3.1.1.3
Inspecting Tubes
After tubes are rolled in place, provide, under manufacturer's supervision,
one person in steam drum and one in mud drum. The person in the steam drum
shall drop a ping pong ball through every tube to be sure that no foreign
matter or misalignment obstructs the tube. After boiler tubes have been
tested, follow the same procedure on the water wall tubes. Remove each
tube that is not in alignment after being installed and install a new tube
in its place.
3.1.1.4
Installing Firebrick
Lay up in air-setting mortar. Dip each brick in mortar, rub, shove into
its final place, and then tap with a wooden mallet until it touches the
adjacent bricks. Mortar thick enough to lay with a trowel will not be
permitted. Maximum mortar joint thickness shall not exceed 3 mm 1/8 inch
and average joint thickness shall not exceed 1.60 mm 1/16 inch.
3.1.1.5
Installing Plastic Refractory
Install in accordance with the manufacturer's recommendations and by
workmen skilled in its application.
3.1.1.6
Installing Casing Insulation
Before application of the insulations, clean exterior surfaces of the
boiler not covered by brick work by commercial blast and finish with one
SECTION 15502N
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