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 ANCHORS, HANGERS, AND SUPPORTS
Section 4.
1 APPLICATION. Anchors, hangers, and supports are used to carry the weight
o f pipes, valves, a n d fittings, as well as the weight of the contained fluid.
When combined with expansion joints and bends, they control and guide pipe
expansion. Common functions of anchors, hangers, supports, and guides include:
q Supporting the full unbalanced pressure of the fluid
q Resisting the strains caused by expansion and compression of the piping
q Supporting the weight of piping, valves, fittings, and fluid
q Eliminating or minimizing vibration and shock
2 ANCHORS.
2 . 1 C o n s t r u c t i o n . Anchors used in underground pipe installations commonly
c o n s i s t of a steel plate welded to both the pipe and the conduit. The other
e n d of the steel plate is embedded in concrete blocks sufficiently large to
p r o v i d e a firm anchor. The concrete may also be cast with the pipe in place;
h o w e v e r , in either method it is important that the concrete extends beyond the
t r e n c h walls and floor into the firm, undisturbed ground. At higher
e l e v a t i o n s where difficulty may be experienced in obtaining adequate rigidity
o f piping supports, the end of the steel anchors used to secure the pipes to
the poles may be guyed to concrete deadmen by wire ropes and turnbuckles. The
w i r e ropes should be installed parallel to the pipeline in both directions.
2 . 2 Reference Design Specifications. A n c h o r s appropriate for distribution
systems should be designed in accordance with NAVFAC Specification 21Y (Latest
Revision), Steam Power Plant, Heating, and Ventilating Equipment and Piping.
3 HANGERS AND SUPPORTS.
3 . 1 C o n s t r u c t i o n . For aboveground systems at lower elevations, concrete
p e d e s t a l s , steel frames, or treated wood frames are used. The spacing may be
1 0 to 15 feet on center, depending on pipe sizes. At higher elevations,
aboveground pipelines may be supported on wood, steel pipe, H-section steel
poles with crossarms, o r steel frameworks fitted with rollers and insulation
saddles.
E x c e s s i v e spacing between hangers will allow the line to sag. In a
s t e a m line, this permits the collection of condensate which impairs the
performance of the system.
3.2 Long Spans. When long spans are necessary, cable-suspension or catenary
systems may be used with supports up to 50 feet on center.
3 . 3 Underground Conduits. Approved manufacturers' standard supports should
be used for underground conduits.
3 . 4 Reference Design Specifications. S u p p o r t s for distribution system
pipelines should conform to requirements specified in NAVFAC Specification 21Y
(Latest Revision), Steam Power Plant. Heating. and Ventilating Equipment and
Piping.
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