There are many ways to classify fans:
1. Fans can be divided into several types according to the materials used, such as iron-cased fans (ordinary fans), fiberglass fans, plastic fans, and aluminum fans. , stainless steel fans, etc.
2. According to the direction of gas flow
Fans can be classified according to the direction of gas flow into centrifugal type, axial flow type, oblique flow type (mixed flow type) and cross flow type, etc. type.
(1) Centrifugal fan. The airflow enters the impeller of the fan axially and mainly flows in the radial direction. This type of fans is made based on the principle of centrifugal action. Products include centrifugal fans, centrifugal blowers and centrifugal compressors. ?
(2) Axial flow fan. The airflow enters the impeller of the fan axially and flows approximately along the axial direction on the cylindrical surface. Such fans include axial fans, axial blowers and axial compressors.
(3) Rotary fan. The rotor rotates to change the volume of the air chamber to work. Common varieties include Roots blowers and rotary compressors.
Fans are divided into: axial flow fans, centrifugal fans and oblique flow (mixed flow) fans according to the flow direction of the airflow after entering the impeller.
3. Fans are divided into press-in local fans (hereinafter referred to as press-in fans) and explosion-proof motors placed outside the flow channel or in the flow channel according to their uses. The explosion-proof motor is placed outside the explosion-proof sealed cavity. Type local fan (hereinafter referred to as withdrawable fan).
4. The fans can also be divided into single-stage, double-stage or multi-stage pressurized fans according to the form of pressurization. For example, the 4-72 is a single-stage pressurized fan, while the high-end fan is a multi-stage pressurized fan.
5. Fans can be divided according to their uses: axial flow fans, mixed flow fans, roof fans, air conditioning fans, etc.
6. Fans can be divided into negative pressure fans, low pressure fans, medium pressure fans and high pressure fans according to pressure.
6. According to the outlet pressure (pressure boost), it is divided into: ventilator (≤15,000 Pa), blower (15,000 to 350,000 Pa), compressor (≥350,000 Pa).
Differences
Centrifugal fans are: low pressure, large air volume, generally the motors are external, there are civilian blowers DF fans, industrial CF11 fans 4-76 fans wait. The axial flow fan refers to a cylindrical, multi-purpose smoke exhaust fan with a built-in motor, while the medium-pressure fan refers to a pressure-type blower used in the kitchen. Generally, the cast aluminum shape is more durable. Extended information
Installation requirements
The foundation of the fan must be level and solid, and the foundation height must be ≥200mm.
The fan and the air duct should be connected with a hose (flexible material and non-combustible). The length should not be less than 200mm, and the pipe diameter should be the same as the fan inlet and outlet size. In order to ensure that the hose does not twist and deform during system operation, it should be installed with appropriate tightness. The canvas hose installed at the suction end of the fan can be installed slightly tighter to prevent it from being sucked in when the fan is running and reduce the cross-sectional size of the canvas hose.
The steel bracket of the fan must be fixed on the concrete foundation, and a rubber vibration-absorbing pad must be added between the steel bracket of the fan and the foundation. All fan and motor components are installed on a single piece of steel bracket, and the steel frame is installed on the vibration-absorbing pad on the top of the foundation. The vibration-absorbing pad is preferably a porous rubber plate.
The pipe diameter at the fan outlet can only be made larger, not smaller. Finally, an insect-proof net must be installed at the air outlet, and a weather cap must be added when the wind is directed upward.
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