Ductwork

Vibro-Acoustics offers a variety of standard and custom isolation and restraint solutions for duct systems. These solutions, combined with our seismic engineering capabilities, give contractors and engineers the advantage of single-source responsibility.

Application Details

Master VIRS Pre-Submittal Package

Neoprene Hangers or Spring Hangers with Neoprene and Bottom Cup provide vibration isolation for suspended equipment. The neoprene element isolates from high frequency vibration and eliminates steel-to-steel contact. Neoprene coated up-stop washer provided for seismic applications to protect against damage.

To keep hanger rods from bending and buckling due to seismic activity, additional steel angles are clamped to our easy-to-install rod stiffener clamp, VAC. Our rod stiffener calculator will determine if and how many rod stiffeners are required based on seismic variables to save labor.

Utilizing the uniquely designed BulletLockTM securing mechanism, the BulletBraceTM is the fastest adjustable cable restraint system on the market.

Custom designed restraint solutions to be used for various structural types, including BulletClampTM. Other difficult structures to be noted are trusses, pan deck, thin concrete deck.

Design Considerations

Structure-Borne Vibration

Problem: Vibration from air turbulence can travel from unit through connected duct work into the structure.

Solution: Spring hangers are recommended on the outlet of equipment and until the vibration is dissipated. Depending on duct size, this set-up usually requires 3 to 5 hangers on either side. Proper calculations should be performed for quantity and locations of the hangers.

Seismic Requirements

Problem: Horizontal and vertical forces applied at the center of the pipe require lateral bracing.

Solution: Properly designed cable or solid restraint system to be installed. Cable system required when duct is isolated.

Problem: Forces are determined by a number of factors including: project location, site class, risk category, component importance factor and equipment location equipment relative to the overall height of the building.

Solution: Certified restraint and anchorage calculations must be submitted to verify loading conditions are met for each piece of equipment.

Problem: Structural attachment may have limited capacity or be difficult to attach.

Solution: Custom designed restraints to be used for various structural types, including BulletClamp. Other difficult structures to be noted: trusses, pan deck, thin concrete deck.

Problem:Net uplift forces on ductwork with spring hangers can cause damage and lead to failure of spring hangers.

Solution: Spring hangers with up stop limit washers to be used.

Design Considerations

Structure-Borne Vibration

Seismic Requirements

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