The fan is a device common to many, found in everyday life and in industry. According to the design features, they are axial, centrifugal and diametrical. For the first time such mechanisms appeared at the beginning of the XVIII century in Britain. They used a steam engine as a drive and were themselves axial.
Centrifugal fan was invented later in Russia by military engineer A. Sablukov. Today they are the most common, especially in industry, where it is necessary to move gas-air mixtures in large volumes. They work from electric motors.
Device and principle of operation
The centrifugal( or radial) fan is designed for moving air or gas-air mixture in ventilation systems of domestic, industrial, commercial, public premises for cleaning it, regulating humidity, ie creating a microclimate favorable for human life.
In its device it has the following elements: spiral housing, blades, impeller, motor. When the engine is turned on, the blades begin to rotate, sucking in air, which by centrifugal force passes into the spiral housing, and then into the air ducts, into the outlet opening perpendicular to the inlet, the air is already cleaned.
Operating conditions of
Centrifugal fans can be operated in rooms where the following conditions are met:
- air temperature( or non-explosive gas-air mixture) is not more than 80 ° C, for bilateral - up to 60 °;
- mechanical impurities should not exceed 1 g / m3;
- in the air does not contain fibrous particles and sticky substances.
Failure to comply with these conditions, exceeding the values leads to a rapid deterioration of the fans and their failure.
Varieties
Based on different criteria, the classification of radial fans can be different.
Depending on the direction of air movement:
- exhaust;
- double suction;
Depending on the air pressure:
- up to 1000 Pa - low pressure;
- 1000-3000 Pa - medium pressure;
- 3000-12000 Pa - high pressure;
Depending on the direction of rotation( suction side):
- right rotation( the blades rotate clockwise);
- left rotation( the blades rotate counter-clockwise).
Product designation - B( fan)
- Product type: Ц or Р - respectively, centrifugal or radial;
- the value of the total pressure coefficient( integer);
- designation of speed - hy;
- designation of the product number in accordance with GOST 10616, in accordance with the size of the outside diameter of the wheel - D.
Designations according to GOST:
So, the designation BP-300-45-2,0 corresponds to the radial fan with a total pressure factor of 300( medium pressure), high speed45, whose impeller diameter is 200 mm.
The main producers of
The fan market today is very rich in both foreign and domestic models. Among them, we can distinguish such brands:
Soler & Palau( Spain) .Almost 300 models of this brand are characterized by impeccable quality and reliability. The case of products is made of galvanized sheet steel, some models have a special protective layer. The Soler & Palau fans have a regulator for changing engine speed, an insulating layer, damping sound waves and vibration, can operate at temperatures from -15 ° to + 400 ° and even in an explosive atmosphere.
Systemair .These compact devices can be used both independently and in ventilation chambers. Fans have a steel casing that protects the mechanism from corrosion. The motor protects the thermal contacts from overheating.
Ostberg .These fans are designed for installation in duct systems of varying complexity and size. The body and impeller manufacturer makes of galvanized steel. They are characterized by wear resistance, a long service life, the ability to adjust the speed of rotation, ease of maintenance. The latter is achieved due to the fact that the impeller and the motor are fixed to the opening door: to clean the fan, you just need to open this door.
Vortice .Fans of this manufacturer can operate at temperatures up to 40 °, circulating large volumes of air: 6300 m3 / h. Such productivity allows using them in semi-industrial and industrial premises.
VEZA .Domestic models of fans are ideally adapted to the regional climate - they are manufactured by individual technology based on a batch-free serial production. They differ in variety of assortment( VAN, VOD, VRAV, CROS, BLOOD, etc.), almost all series are produced in frost-proof, explosion-proof, seismic resistant version.
Price
The cost depends on many factors, the main among them are the following:
- manufacturer;
- overall dimensions or size;
- scheme of execution( explosion-proof, frost-resistant, corrosion-resistant, for corrosive media, etc.);
- material of execution( ordinary or stainless steel);
- engine parameters - power, dimensions, protection class, etc.
In each case, the price of the device is individual and has a fairly wide spread. Depending on the parameters you need, you can buy a centrifugal fan from 5.5 to 350 thousand rubles.
