Central Vacuum Cleaning Systems
Industrial centralised vacuum cleaning systems are used for removing dust buildup from floors, flat surfaces, plant, machinery and structural elements of facilities. This solution is also used as local dust extraction stations at workplaces with high and directional dust emissions. Extraction hoods and extensions are provided for this type of setup.
Standard central vacuum cleaning systems are designed for free-flowing, dry, non-agglomerating and non-explosive dusts.
Explosion protected central vacuum systems are used with potentially explosive dusts and include certified explosion certified equipment for application in relevant explosion zones (as required by the customer) and the necessary explosion protection system (explosion suppression, venting and isolation). Our services may also include preparation of an Explosion Assessment Document, or an Explosion Protection Document.
- provision of turnkey central vacuum systems,
- modernisation of existing central vacuum systems,
- explosion protection of central vacuum systems,
- preparation of documents in compliance with ATEX Directives,
- fabrication of system components for central vacuum systems.
Basic components of a central vacuum cleaning system:
- filter separator,
- the Vacuum Source,
- control system,
- anciliary equipment and consumables,
- explosion protection system.
Extracting fine dusts is fraught with potential explosion hazards. It is therefore necessary to take some basic safety measures in order to reduce the risk. This is an obligation under the Minister of Economy Decision on minimal health and safety requirements in the workplace where explosive atmospheres may occur. (J.O.L. of 10/07/2013). In practice it boils down to the following series of activities:
- assessment of risks arising from explosive atmospheres plus identification and marking of explosion hazard zones,
- implementation of explosion protection measures, such as: use of equipment certified to work in relevant explosion zones, potential equalisation bonding and grounding, use of air-tight or inert gas systems,
- deployment of certified explosion protection equipment (explosion suppression, venting or isolation).
The fixed piping system can be created using smooth flow thin walled tubing in galvanised steel or painted thick-walled pipes.
Pipe sections and fittings are joined using self rubberised self-sealing clamps. The unique rubber seals prevent contact between pipework components, which reduces noise and allows for stress compensation in the pipework.
All connections in explosion protected piping are bonded to equalise their static potentials and the entire pipework is grounded, which prevents static discharge and consequently a potential explosion.
The pipe couplings allow for an easy installation, quick rework or stripping for refurbishment.
The fixed piping system can have an unlimited number of hose connection points across several floors. Each connection point has a self-closing gate valve to insert a hose and nozzle. This type of setup ensures ease of use and high air-tightness, which is required achieve satisfactory negative pressure levels in the pipework.
The system can be started from one point or several points, which depends on its size and complexity. Micro-switches can be provided as an option to start the system when a hose is plugged into one of the vacuum points.
Central vacuum systems commonly utilise filter separators of welded tubular construction in 3 mm sheet with cyclonic separation technology and air-cleaned filtration media. A variety of bag material can be used to suit the product characteristics, including water resistant, oil resistant or antistatic.
Filter efficiency is maintained with an automatic reverse-pulse filter cleaning system. Only one row of filtration media is cleaned at a time with the rest being in use.
Dust separated from air is collected in the bottom part of the filter separator to be conveyed, via a rotary valve, to a container underneath the unit for further transport / treatment.
The Vacuum Source
Depending on the size of the system (flow resistance) suitable negative pressures can be produced by one of the three solutions: regenerative exhausters, positive displacement pumps, multi-stage centrifugal exhausters.
Typical negative pressures range from 100 mbar too 550 mbar.
Centrifugal exhausters are usually placed in enclosed housings and acoustic dampers are installed at the outlet in order to reduce the noise. Vibration levels and vibrations transmited to the support structure can be reduced through the use of vibration insulators and elastic duct connections.
Exhausters are supplied in sound-proof casings and installed on vibration insulators. Exhaust dampers can be installed at the outlet to satisfy stringent noise requirements.