Kinetics SFH hangers are recommended for use near critically quiet
areas for isolating any suspended source of both audible and inaudible noise
and vibration. Suspended mechanical equipment such as in-line fans, cabinet
fans, and piping and ductwork in close proximity to mechanical equipment
are typical uses of SFH hangers.
High sound transmission loss ceiling systems can be effectively isolated
by the use of SFH hangers in the ceiling suspension system. This hanger
model is particularly suitable for use in isolated ceiling systems used
to shield spaces from mechanical equipment rooms, flyover aircraft, and
similar sound isolation involving predominantly low frequency noise.
Kinetics' minimum recommendation for the placement of spring hangers is
that they be installed on all piping in the equipment room and on the first
50' (15 m) for piping that extends outside of the equipment room. For typical
installations, the three spring hangers closest to the equipment should
have equal deflection to the equipment isolators. The remaining spring hangers
should have a minimum deflection of 1" (25 mm). In noise sensitive areas,
the pipe hangers selected should have the same deflection as that specified
for the equipment isolation and all piping in the building should be isolated.
Standard SFH hangers are shipped fully assembled and ready for installation
in threaded rod suspension systems.
Kinetics SFH hangers are available in a wide range of load and static deflection
selections and can be provided with labor saving accessories for adaption
to wire or strap suspension systems, and spring may be preloaded for ease
in erecting piping at a fixed elevation.
Vibration isolators for suspended equipment with minimum static deflection
requirement exceeding .4" (10 mm), and where both high and low frequency
vibration is to be isolated, shall be hangers consisting of a laterally
stable steel spring in series with a precompressed molded fiberglass insert,
complete with a load plate and assembled in a stamped or welded steel bracket.
The bracket shall be finished with an polyester powder coating. The manufacturer
shall provide independent laboratory testing showing that the bracket with
this finish has endured a minimum of 1,000 hours of exposure to salt spray
fog testing per ASTM B117 without signs of corrosion.
The fiberglass insert shall be individually coated with a flexible, moisture-impervious
elastomeric membrane. The insert shall be molded from glass fibers with
fiber diameters not exceeding .00027" (6.8 microns) and with a modulus of
elasticity of 10.5 million PSI (738,223 kg/cm2).
Natural frequency of fiberglass vibration isolators shall be essentially
constant for the operating load range of the supported equipment.
The spring element shall have a minimum lateral stiffness of 1.0 times
the rated vertical stiffness.
Vibration isolators shall be color coded or otherwise identified to indicate
The hanger bracket shall be designed to carry a 500% overload without failure
and to allow support rod misalignment through a 30° arc without metal-to-metal
contact or other short circuit.
The 1" and 2" hanger brackets shall incorporate spring caps with indexed
steps which correspond to the washer diameter of appropriately sized hanger
rod to keep the rod centered in the spring cap and reduce rod misalignment.
The spring caps are protected under U.S. patent number 5,653,426.
Isolation hangers shall be selected by the manufacturer for each specific
application to comply with deflection requirements as shown on the Vibration
Isolation Schedule or as indicated on the project documents.
The combination isolation hanger assembly with fiberglass insert shall
be Model SFH, as manufactured by Kinetics Noise Control, Inc.