Regulator shall have an adjustable outlet pressure range not less than 34
to 690 kPa (gage) 5 to 100 psig with not less than four ranges. Provide
external adjusting screw for adjustment throughout each spring range.
Provide internal pressure tap for outlet pressure regulation.
2.8
BREECHING, EXPANSION JOINTS, STACKS, DAMPERS, AND ACCESSORIES
2.8.1
Breeching
Provide with rectangular cross section stiffened on sides, top and bottom
and fabricated of not less than 5 mm 3/16 inch thick black steel plate
unless otherwise noted. Stiffeners shall be not less than 65 by 50 by 6 mm
2 1/2 by 2 by 1/4 inch steel angles welded to exterior with 50 mm 2 inch
leg outstanding. Stiffeners shall not exceed one meter 3 feet on center.
Breeching shall connect to [each boiler flue gas outlet,] [intermediate
heat recovery equipment,] [air pollution control equipment,] [and to stack
as required].
2.8.1.1
Breeching Connections and Joints
Weld or bolt breeching joints unless indicated otherwise. Welding shall
conform to AWS D1.1/D1.1M and AWS D1.3. Bolts for bolted connections shall
be not less than 15 mm 1/2 inch diameter and spaced not more than 80 mm 3
inches apart, with bolts, lockwashers and nuts being hot-dipped galvanized.
Provide bolted joints with a minimum of 3 mm 1/8 inch thick non-asbestos
gaskets, suitable for the intended use. Bolt breeching connections to all
boilers, equipment items, dampers, expansion joints, and breeching
accessories. Flanged breeching connections to equipment shall be drilled
to match flanges on equipment. Seal weld flanged joints to make connection
gas-tight.
2.8.1.2
Uninsulated Breeching
Thoroughly wire brush breeching which is not to be insulated and clean by
degreasing with nonflammable solvent such as trichloroethylene prior to
painting.
2.8.1.3
Breeching Access Doors
Provide where indicated. Construct access doors with frame and hinged door
of cast iron or reinforced steel plate. Frame shall be not less than 635
by 940 mm 25 by 37 inches with access opening of 457 by 762 mm 18 by 30
inches. Connection to breeching shall be gasketed and made with minimum 15
mm 1/2 inch diameter hot-dipped galvanized bolts, lockwashers, and nuts
spaced not more than 125 mm 5 inches on center. Each side of access door
shall have not less than two quick-clamp positive closing latches, with
long side opposite hinges containing three clamps to give a gastight seal.
Side of access door opposite hinges shall contain a minimum 80 by 125 mm 3
by 5 inch size handle. Provide a gasket consisting of 10 mm 3/8 inch
diameter fire resistant resilient rope seal and mastic compound between
access door and access door frame.
2.8.1.4
Breeching Cleanout Doors
Provide where indicated. Construct cleanout doors of not less than 5 mm
3/16 inch thick steel plate. Secure cleanout doors to a 32 by 32 by 5 mm 1
1/4 by 1 1/4 by 3/16 inch thick angle frame with 10 mm 3/8 inch hot-dipped
galvanized mounting bolts welded to the angle frame and spaced not more than
150 mm 6 inches on center. Weld frame to breeching and provide a 1.60 mm
SECTION 15501N
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