The use of an HVAC system is essential to regulate temperature, humidity and air quality, factors that are increasingly essential for the health of the environment. In order for the system to be efficient, it is important to consider some factors that can affect its correct functioning, such as, for example, the mechanical vibrations produced.
What kind of problems can be encountered if a system is not isolated from vibrations?
Vibrations generated by machinery installed in residential buildings or workplaces can be a source of disturbance and significantly reduce people’s well-being. The UNI 9614 standard sets precise limits on the acceptability values of these vibrations by dividing the types of premises and buildings. In particular, the following uses are identified: critical areas, homes, offices and factories. Critical areas identify structures such as hospital operating rooms or technical rooms where precision work is carried out.
It is essential to stay below these acceptability limits to ensure adequate comfort and avoid legal disputes that can culminate in expensive retrofitting work. Furthermore, vibrations from non-isolated machinery can be transmitted to rigid connections such as pipes and beams, generating structural noise and significantly reducing the useful life of the systems.
What solution does Soleco propose to overcome these problems?
In residential buildings the most problematic vibrations are often generated by air conditioning systems. The vibrations of these units are produced by rotating components such as fans, compressors and motors. These vibrations have very different frequencies and for correct isolation it is important to carry out studies and/or surveys. The selection of an incorrect anti-vibration can cause the isolated system to have natural frequencies close to the forcing frequencies generating local or global resonance phenomena.
In the graph below, three main sources of vibrations of an evaporative tower can be identified:
- Fans with forcing frequencies below 10 Hz
- Engine with vibration frequencies generally higher than 25 Hz
- Air pressure.
To isolate low frequencies generated by fans, it is not enough to use bearings, but it is necessary to provide high deflection spring systems, while to isolate forces with higher frequencies (generally above 25 Hz) it is possible to provide elastomer anti-vibration mounts. In addition to anti-vibration mounts, Soleco designs and sizes inertial bases that contribute to reducing the amplitude of vibrations and to uniforming the load on the support points.
If the installation takes place on the roof, what complications can there be and what solution does Soleco provide?
The technical building regulations require that systems and non-structural elements are verified, together with their connections to the structure, for the seismic action corresponding to each of the limit states considered. Therefore, when using standard anti-vibration devices, it is essential to analyze the design seismic action and provide any containment brackets. Containment brackets can lead to various problems, including dilation of the processing time and high costs for ad hoc design. To overcome these problems, Soleco offers its range of anti-seismic anti-vibration devices, which at the same time isolate mechanical vibrations and guarantee seismic anchoring to the unit. The selection of anti-seismic devices is carried out by the Soleco Technical Office which verifies the loads and the isolation factor. The strong point of Soleco products is the seismic qualification obtained at the Polytechnic of Milan following tests according to ANSI-ASHRAE 171/2008 regulations and validated by Lloyd’s Register.
What other services does Soleco offer its customers?
Soleco provides its customers with a free selection and analysis service for anti-vibration devices.
The selections can concern a single machine or an entire range of machines. Many manufacturers rely on Soleco’s kit service to reduce the management costs of these accessories. Through modern analysis systems, Soleco can divide and categorize a huge number of machines, selecting the best set of anti-vibration devices for each category. The anti-vibration kits are supplied with manuals, screws and accessories such as anchoring brackets and jacks. The company also guarantees after-sales assistance, on-site consultancy and, when necessary, carries out vibrometric measures to identify the best solution. Experience and continuous research allow Soleco to satisfy increasingly specific requests for those who work in the sector, guaranteeing quality and innovation.
