4-72/B4-72/F4-72 General/Explosion proof/Anti corrosion Medium and High Pressure Industrial Centrifugal Fans

1. Purpose:

Type 4-72Centrifugal ventilation fanIt can be used for indoor ventilation and air exchange in general factories and large buildings. Transport air and other non self igniting, harmless to human health, and non corrosive gases to steel. The B4-72 fan can be used for ventilation and exchange of flammable and volatile gases. There shall be no viscous substances, dust or hard particles in the gas, with a concentration not exceeding 150mg/m3. The gas temperature shall not exceed 80 ℃.

The performance, selected components, and foundation dimensions of B4-72 fan are consistent with those of 4-72 fan, and can be selected according to its sample. The structure of the fan is basically the same as the 4-72 type. The No.2.8-6A adopts the B35 type motor with flange and foot, while the No.6-12C and D motors use the YB series corresponding to the Y series in this table, and the installation form is B3.

The F4-72 fan is made of stainless steel and fiberglass material for transporting corrosive gases, and its performance and foundation size are the same as the 4-72 type.

2. Form

When viewed from the side of the electric motor, if the impeller rotates clockwise, it is called a right cyclone machine, represented by "right"; if the impeller rotates counterclockwise, it is called a left cyclone machine, represented by "left".

The outlet position of the fan is represented by the angle of the air outlet of the casing. The adjustment range for the air outlet position of 4-72 type fans No.2.8~12 is 0 °~225 ° when they leave the factory; The interval is 45 degrees. NO.16、 There are three fixed positions for the 20 air outlets: 0 °, 90 °, and 180 °, which cannot be adjusted and must be specified when ordering.

3. Structural characteristics

NO.2.8~6 in the 4-72 type fan are mainly composed of impellers, casings, inlet air, and other parts matched with direct connected motors. NO.8~20 not only have the above-mentioned parts, but also have transmission parts.

(1) The impeller consists of 10 aft inclined blade types, a curved front plate, and a flat rear plate. Made of steel plate, copper plate or cast aluminum alloy, and calibrated for dynamic and static balance, it has good air performance, high efficiency and smooth operation.

(2)The casing is made of steel plate and processed into an Archimedean spiral shape using a CNC laser cutting machinevolute，After welding,The casing is made in two different types. NO.2.8~12 shells are made as a whole and cannot be disassembled. NO.16~20 shells can be made into a three open type. In addition to being divided into two halves along the horizontal plane, the upper half is vertically divided into two halves along the centerline and connected with bolts.

(3)The air inlet is made into a convergent streamlined overall structureInstalled on the side of the fan, with a curved cross-section parallel to the axial direction, it allows gas to enter the impeller smoothly with minimal loss.

(4) The transmission part consists of a main shaft, bearing housing, rolling bearings, pulleys or couplings.