the cross section indicated. Compact mastic thoroughly.
Immediately before placing mastic, coat tank surfaces to be in
contact with concrete ring with a coat of AASHTO M 118bituminous
material.
]3.1.2
Piping
Unless specified otherwise, erection, welding, brazing, testing and
inspection of piping shall be in accordance with ASME B31.1 and Section
15216N WELDING PRESSURE PIPING. Piping shall follow the general
arrangement shown. Cut piping accurately to measurements established for
the work. Work piping into place without springing or forcing, except
where cold-springing is specified. Piping and equipment within buildings
shall be entirely out of the way of lighting fixtures and doors, windows,
and other openings. Locate overhead piping in buildings in the most
inconspicuous positions. Do not bury or conceal piping until piping has
been inspected, tested, and approved. Where pipe passes through building
structure, conceal pipe joints but locate where they may be readily
inspected and building structure not be weakened. Avoid interference with
other piping, conduit, or equipment. Except where specifically shown
otherwise, run vertical piping plumb and straight and parallel to walls.
Install piping connected to equipment to provide flexibility for vibration.
Support and anchor piping so that strain from weight of piping is not
imposed on equipment.
3.1.2.1
Fittings
Provide long radius ells on welded piping to reduce pressure drops.
Mitering of pipe to form elbows, notching straight runs to form full sized
tees, or similar construction shall not be used. Make branch connections
with welding tees, except factory made forged welding branch outlets or
nozzles having integral reinforcements conforming to ASME B31.1 may be
provided.
3.1.2.2
Grading of Pipe Lines
Unless indicated otherwise, install horizontal lines of steam and return
piping to grade down in the direction of flow with a pitch of not less than
25 mm in 9 meters one inch in 30 feet, except in loop mains and main
headers where flow may be either direction. Pitch air lines to source of
supply, and make provisions for draining off condensate. Install water
lines to drain to a shutoff valve.
3.1.2.3
Anchoring, Guiding, and Supporting Piping
Anchor and support piping in a manner such that expansion and contraction
will take place in the direction desired, prevent vibration by use of
vibration dampeners, and prevent undue strains on boilers and equipment
served. Fabricate hangers used for the support of piping of 50 mm 2 inch
nominal pipe size and larger to permit adequate adjustment after erection
while still supporting the load. Provide wall brackets where pipes are
adjacent to walls or other vertical surfaces which may be used for
supports. Provide supports to adequately carry weight of the lines and
maintain proper alignment. Provide inserts and sleeves for supports in
concrete where necessary and place in new construction before pouring
concrete. Provide insulated piping with a pipe covering protection saddle
at each support. Provide pipe guides and anchors of approved type at
points where necessary to keep pipes in accurate alignment, to direct
expansion movement, and to prevent buckling and swaying and undue strain.
SECTION 15501N
Page 149
Previous Page
