branch connections with welding tees except factory made forged welding
branch outlets or nozzles having integral reinforcements conforming to ASME
B31.1 may be used, provided the nominal diameter of the branch is at least
one pipe size less than the nominal diameter of the run. Run piping as
indicated, and avoid interference with other piping, conduit, or equipment.
Run vertical piping plumb and straight and parallel to walls, except where
specifically shown otherwise. Do not trap lines, except where indicated.
Use reducing fittings for changes in pipe sizes. The use of bushings is
prohibited. In horizontal lines 65 mm 2 1/2 inches and larger, use
reducing fittings of the eccentric type to maintain the bottom of the lines
in the same plane for steam lines and to maintain the top of the lines in
the same plane for condensate lines except where a trap or pocket would
result. Provide suitable size sleeves for lines passing through building
structure. Install piping connected to equipment to provide flexibility
for thermal stresses and for vibration. Support and anchor pipe so that
strain from weight and thermal movement of piping is not imposed on the
equipment. Thoroughly clean each section of pipe, fittings, and valves of
foreign matter before erection. Before placing in position, clean the
inside of black steel pipe by rapping along its full length to loosen sand,
mill scale, and other foreign matter; pipe 50 mm 2 inches and larger shall
have a wire brush of a diameter larger than that of the inside of the pipe
drawn through its entire length several times. Before final connections
are made to the apparatus, thoroughly wash out the piping interior with
water. Blow out steam piping with high-pressure steam, if available, or
compressed air, removing rust, oil, chips, sand, and other material. Plug
or cap open ends of mains during shutdown periods. Do not leave lines open
at any place where any foreign matter might accidentally enter pipe.
3.1.1.1
Welding
a.
Welding of Piping: Welding of joints in piping, butt welds,
fillet welds, bends, loops, offsets, and preparation and cleaning
of pipe shall be in accordance with ASME B31.1. Welds shall be
visually examined and meet acceptance standards indicated in
Chapter VI of ASME B31.1.
b.
Quality of Welds:
Quality of welds, correction of defects,
stress relieving, and preheating shall be in accordance with ASME
B31.1.
c.
Arc Welding and Gas Welding:
In accordance with ASME BPVC SEC IX.
3.1.1.2
Brazing and Soldering
a.
Brazing and soldering procedure qualification shall conform to
ASME B31.1. Brazing procedure for joints shall be as outlined in
the CDA A4015.
b.
Soldering, soldering preparation, and procedures for joints shall
be in accordance with ASME B31.1 and as outlined in the CDA A4015.
c.
Copper Tube Extracted Joint: An extracted mechanical tee joint
may be made in copper tube. Make joint with an appropriate tool
by drilling a pilot hole and drawing out the tube surface to form
a collar having a minimum height of three times the thickness of
the tube wall. To prevent the branch tube from being inserted
beyond the depth of the extracted joint, provide dimpled depth
stops. Notch the branch tube for proper penetration into fitting
to ensure a free flow joint. Braze extracted joints using a
SECTION 15183N
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