Spring hanger isolators protect the support structure from vibration damage

Today, the buildings and structures are designed not only with architectural excellence but also with a lot more factors in consideration like the seismic constraints and vibration dynamics. In general, the people have also become aware of the damage caused by the vibrations. The designers take care of these aspects or make recommendations for vibration protection when they design a new product. The industries buying new machinery and equipment also install the right kind of anti-vibration mounts and isolators before they install the machines. The HVAC systems, piping and ducting also need to be isolated from the structure to prevent damage due to vibrations. Keeping this in mind a few vibration damping product details have been brought out here.

Hanger vibration isolators: Wherever the equipment is suspended from the ceiling or the support structure the hanger vibration isolators are used. These pipe vibration isolators are very simple in design with a metallic rectangular plate bracket that is either stamped or welded. Adequate corrosion resistance is provided through powder coating. The pipe spring hangers further consist of a deflection spring element, a spring cap and an elastomer element. The hanger vibration isolators are designed in such a manner that they can take a support rod misalignment of almost 30 degrees thus making the installation very flexible. The spring deflections are also available from 25 mm to 100 mm with load capacities in the range of 15 to 1500 Kg. The typical applications are pipe supports and hangers, ducting support and hangers, in-line fans and cabinet fans etc.

HVAC hangers: For applications requiring the Heating Ventilation and Air Conditioning (HVAC) equipment to be suspended from the ceiling or structural members, HVAC hangers are used. The HVAC hangers are very similar to the hanger vibration isolators described above with the difference coming in the deflection and load capacities. In the HVAC equipment, the dynamic forces also come into play when we suspend the equipment containing the rotating parts. The entire ducting for the HVAC systems is suspended using the ducting support and hangers. The heavier parts like the air conditioning unit, AHU etc. can be directly mounted on the rooftop using the air conditioning anti-vibration mounts.

Generator vibration isolator: There are two types of vibrations that occur within a generator system. One is the torsional vibration generated due to the engine combustion forces while the other is the linear vibration which can be due to many reasons. To tackle these linear vibrations, the engine and the alternator of the generator set are isolated from the base frame by using elastomeric engine mount vibration isolators. A number of elastomeric bushings are used for mounting the other electronic equipment and enclosures on the frame. The generator vibration isolators reduce the transmission of vibrations to the other components as the mechanical energy is dissipated in the elastomeric element. The equipment vibration isolation pads interrupt the energy transmission path between the rotating equipment and its surrounding support structure. The load capacity of the elastomeric isolators is limited as compared to the spring isolators. However, they are well suited for dampening low weight equipment on the generator set. The strength of the elastomeric isolators lies in their shear loading resistance when loaded in the vertical direction. The elastomeric generator vibration isolators not only resist misalignment forces but also dampen the high-frequency vibrations effectively.

Rear spring shackles: Shackles are commonly used in everyday life and you can easily observe the rear spring shackles in almost all four wheel automobiles. The shackles hold the rear leaf springs in position and together with it provides the damping action in the rear suspension of the vehicle. A typical rear shackle with vibration isolation is a product with metal to rubber bonding. The metal part is powder quoted for corrosion resistance. The elastomer prevents the metal to metal contact and hence, acts as a vibration isolator. The rear spring shackle also comes in an extended version in case there is such a requirement.

Andre HVAC International Inc. is a solution provider when it comes to fulfilling the anti-vibration needs of the clients. The AHI product range is very large and suits the multiplicity of the anti-vibration requirements raised by the clients. Whether you want to mount your equipment on the floor or on the rooftop, a huge variety of anti-vibration mounts are available depending on the load and deflections. Similarly, there are a number of anti-vibration suspension products like the equipment isolation spring hangers that can protect the surrounding structures from the ill effects of vibrations generated from suspended equipment.

Go in for seismic isolators and spring hangers for your buildings

Seismic restrained isolator: The seismic spring mounts consist of a metallic housing that restricts the vertical and horizontal movement of the supported equipment during a seismic impact. The neoprene elastomer element is fitted in series with the spring coil. It prevents the metal short circuiting between the supporting member and housing. The seismic vibration isolators are designed to withstand forces of 1G magnitude along the horizontal and vertical planes without any yield or failure. The seismic vibration damping mounts function normally as vibration isolators under normal operating conditions.

The features of the seismic spring isolator can be summarized as:

  • Restraint along all major axis with physical limits in the vertical direction
  • Free height and operating height are fixed
  • Adequate rust protection for steel parts and spring coils
  • Easy replacement of spring coils in the field

Seismic spring mounts: The floor mounted seismic spring dampers are used for indoor and outdoor equipment isolation. The welded housings in the seismic spring mount for

Seismic spring mounts:

Seismic spring mounts:

deflection, limit the lateral and vertical movement. The typical use of seismic spring isolators is for cooling towers, chillers, air handling units, and base-mounted fans. The seismic spring is epoxy powder coated while the steel parts are hot dip galvanized for a long service life. The seismic brackets are also used along with other seismic restraint products for better results.

Spring isolation hangers: The vibration hangers are housed in a stamped or welded hanger bracket. The color coded coil spring indicates the load and deflection characteristics of the spring hangers. The metal to metal contact is prevented by the use of a molded fiberglass insert or an elastomer element. The spring in the sound isolation hangers has lateral spring stiffness equal to the rated vertical stiffness. The spring hanger allows for support rod misalignment through a 30-degree arc.  The vibration hanger is suitable for isolation of low speed suspended mechanical equipment like fans and pumps etc.

Piping spring hangers: The anti-vibration hanger is recommended for use around critically quiet areas for the isolation of vibration and noise produced by suspended piping and

Piping spring hangers

Piping spring hangers

ductwork. The pipe support and hangers prevent the vibrations from getting transmitted to the supporting structure. The sound isolation hanger’s rubber absorbs the high-frequency vibrations while the spring takes care of the low-frequency vibrations. The spring hanger extensions and spring brackets are used in tandem with the pipe spring hangers for ease of installation and improving the performance of the isolation system. The swing hangers with spring link are used in the application where the fluid temperature causes the thermal expansion of the piping.

Andre HVAC International Inc. has been providing solutions to builders and designers for adequate seismic protection since it came into existence in 2003. It also has a wide range of products in the spring hanger pipe support and spring ceiling hanger segment used for acoustic isolation in buildings. AHI provides the support to the customers in the selection of the anti-vibration hangers and other seismic restrained isolators.