INSTALLATION OF AMC-MECANOCAUCHO® VT ACOUSTIC HANGERS IN SNOZONE, MILTON KEYNES, UNITED KINGDOM
BUILDING INFORMATION
Xscape Milton Keynes (Buckinghamshire) opened in July 2000 and is an important feature of the Central Milton Keynes skyline as seen from the east. The front of the Xscape building is 44 metres high, making it the second tallest building in Milton Keynes after Mellish Court in Bletchley. Xscape Milton Keynes has a real snow ski slope, a cinema with 16 cinemas, several shops and restaurants, a casino and a trampoline park.
This ski and snowboard slope is owned by the company Snozone and is the largest real snow resort in Europe. In order to maintain the low temperatures in the facilities, a large number of refrigeration units are necessary throughout the entire ski resort. The cooling units have been due for reconditioning and this task has been carried out by the company Star Refrigeration. Due to the inherent vibrations which are present in these units it is essential to isolate this equipment from the surrounding structures. AMC MECANOCAUCHO® have been assisting in this area to provide the necessary vibration isolators. The cooling equipment (CA 13236) is the one shown in the image below, which is suspended from the ceiling inside the Snozone.
The technical team of AMC MECANOCAUCHO® participated in the selection of the vibration isolators according to the specifications set out by Star refrigeration. To achieve this a 3D simulation model is prepared that represents the complete equipment and the supports distributed according to the specification, as can be seen in the following image. It is key to consider the load that each support has to withstand. Due to the variation in loading across the unit different acoustic hangers have been selected, each with its own stiffness characteristics to suit.
For this application the type of acoustic hanger selected was the AMC-MECANOCAUCHO® VT. This range is designed for the suspension of acoustic false ceilings and machinery working from as low as 450 rpm, natural frequencies achieved can range from 2 to 8Hz. The springs are manufactured from a high-quality steel and are located in a rubber support. This support prevents the possibility of acoustic bridges being made in the event of misalignment of threaded rods (you can see in the image below the specifications of the rubber support). The metal components have a high corrosion resistance thanks to the bichromate electrolytic finish. The shape of the external housing is rectangular and allows for enough space for any possible lateral displacement of the spring. In the following two images you can see the 3D models of the two different models of selected VT supports (VT-150 in blue and VT-500 in light grey), and also the graph of the elastic properties of both options.
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The objective of these supports has been to isolate the vibrations from the cooling equipment itself, so that they are not transmitted to the upper supporting structure, resulting in unwanted noise problems. The following two images show the results of isolation and natural frequencies obtained with the mixed configuration of the two different VT models used.
| Isolation X (%) | Isolation Y (%) | Isolation Z (%) | |||
|---|---|---|---|---|---|
| 97.11 | 94.95 | 93.94 | |||
| Main Order | Excitation Frequency (Hz) | Expected Main Excitation (Hz) | Maximum Natural Mode to avoid Amplification | Maximum Natural Mode (Hz) | Isolation starts at (rpm) |
| 1,0 | 25.00 | 25.00 | 17.68 | 7.75 | 657.86 |
| Mode 1 | Mode 2 | Mode 3 | Mode 4 | Mode 5 | Mode 6 | |
|---|---|---|---|---|---|---|
| Fe (Hz) | 4.00 | 4.07 | 5.02 | 5.79 | 6.57 | 7.75 |
| X | 0.00 | 1.00 | 0.00 | 0.02 | 0.73 | 0.00 |
| Y | 1.00 | 0.00 | -0.20 | 0.00 | 0.00 | -0.39 |
| Z | 0.19 | 0.00 | 1.00 | 0.00 | 0.00 | -0.09 |
| PhiX | 0.53 | 0.00 | 0.02 | 0.00 | 0.00 | 1.00 |
| PhiY | 0.00 | -0.49 | 0.00 | 0.01 | 1.00 | 0.00 |
| PhiZ | 0.00 | -0.01 | 0.00 | 1.00 | -0.02 | 0.00 |
Finally, AMC MECANOCAUCHO® has visited the application site to review the completed installation. AMC MECANOCAUCHO® takes pride in monitoring acoustic projects from the project phase to the final installation. The following image shows the completed assembly of the cooler units.
If you have further questions or a similar project do not hesitate to contact our application engineers.
