Vibration Isolation

IAC designs, manufactures and installs anti-vibration mounts to combat structure-borne noise and vibration. Vibration Isolation of Building Services equipment is an accepted and essential part of every Heating, Ventilating and Air Conditioning (HVAC) installation.

With modern day design, equipment speeds have become faster, and concern with low RPM, while theoretically correct, is becoming less and less important. At the same time, modern buildings are constructed using lighter structures than in the past. This means they require greater protection if noise and vibration are to be prevented from being structurally transmitted to critical areas.

IAC supplies Anti-Vibration solutions that effectively combat such structure-borne noise and vibration. We offer an extensive range of vibration isolation equipment including pads, springs and hangers. Vibration Isolators and Anti-Vibration Mounts are ideal, for example, in creating floating floors for gymnasiums, or performance spaces.

IAC has long experience in the design and supply of vibration isolation solutions for a wide variety of HVAC solutions. Our products adhere to the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) guide. IAC delivers high quality solutions that match or exceed your desired performance requirements. Contact our Building Services Team for more information.

Vibration Isolator Product Types

Isolation Pads: Types NR and NRC are isolation pads supplied in sizes 460mm x 460mm or smaller sizes cut to order. NR is 10mm thick cross-ribbed neoprene pad giving up to 2mm deflection. NRC is 25mm thick neoprene-cork-neoprene pad giving up to 4mm deflection.
Rubber-In-Shear Mounting: RVD type mountings are moulded from high-grade synthetic rubber with added anti-ozone and anti-oxidant agents. Threaded inserts are imbedded into the top and steel reinforcing plates at the bottom of the mountings. RVD mountings are capable of supporting loads up to 873Kg and provide up to 12mm deflection.
Open Spring Mountings: Types SW1A, SW1, SW2 and SW3 are adjustable freestanding open spring mountings with combination levelling bolt and equipment fastening bolt. Ribbed neoprene ‘noise-stop’ pads are bonded to the base plates. Spring elements are designed for Horizontal l-to-Vertical spring ratio of 1:0. Standard spring deflections 25mm, 50mm and 75mm. Higher deflections up to 150mm available on request.
Aluminium House Springs: Types XLS, XL, XLW and XLW2 are spring isolators with Aluminium housings consisting of top and bottom sections separated by permanently lubricated neoprene inserts that limit horizontal motion. Equipment mounting and spring adjustment may be made with an external levelling bolt as shown or alternatively with internal adjusting nut on request. A neoprene-ribbed pad is bonded to the base of each isolator. Type XL isolators provide 25mm and 50mm deflection for loads up to 1364Kg.
Steel Caged Springs: Types CT1 and CT2 spring isolators are primarily suitable for cooling towers, where restraint for wind conditions and changing water level is necessary. The housings are welded steel and are generally furnished Hot Dip Galvanised for outdoor installations. Springs are PVC coated. Type CT isolators are custom made for any local capacity and for spring deflections 25-150mm. These isolators are also suitable for heavy equipment such as boilers and chillers. In particular, where it is desirable to have the housings serve as a blocking device during installation and the vertical restraints prevent the equipment from rising when drained of water.
Rubber-In-Shear and Spring Hangers: Types BRD, BS and BSR rubber-in-shear hangers comprise 10mm – 12mm deflection rubber elements housed in rectangular steel hanger boxes. Types BS and BW hangers comprise 25mm deflection steel helical springs of various load ratings housed in steel boxes. Types BSR and BSW have rubber-in-shear elements in series with the steel spring. All hangers can be fitted with a load transfer plate (prefix ‘P’) to hold the equipment or piping at a fixed elevation during installation 50mm deflection spring and combination hangers available on request.

Inertia Bases and A.V. Rail Product Types

Inertia Bases: Type CPF There are two main reasons why inertia bases are necessary for certain items of equipment. Firstly, for equipment such as compressors, which can exhibit high out of balance forces, the inertia base reduces the amount of vertical movement that would otherwise occur and transmitted to connecting pipe work. Secondly, for ‘top heavy’ equipment like belt driven pumps, the inertia base lowers the centre of gravity and increases the plan area of the base of the installation thereby greatly improving stability.

For items requiring increased stability only, a mass ratio of 1.5 times the equipment weight is usually sufficient. For items with high out-of-alance forces the ratio can increase typically from 2 to 5 times the equipment weight. Type CPF inertia bases consist of a perimeter steel concrete pouring form, with reinforcing bars and height saving brackets for attachment of Type SW1 spring isolators. The perimeter frame is designed to have a depth 1/12 of the longest span but not less than 150mm deep. The inertia base should be sized to have a minimum overlap of 100mm around the equipment base.
A.V. Rails: Type SR vibration isolation rails are a means of strengthening equipment bases that would otherwise not accept the isolator point loads. Bolt holes are provided for bolting equipment to the rails and isolators are spaced along the rails on sufficiently close centres to limit deflection of the rail to 1/360 of the unsupported span. For special applications, the rails may be structural channels or beams with either rubber or spring isolators as required. Type WSB welded steel vase frames can be provided when even greater structural support is required.