• Durability: Vinylester resin, UV protection, extended service life.
• Customizable: Computer strain analysis, G2.5 balance, low vibration risk.
• Easy Maintenance: Oil bath bearings, heat/corrosion resistant, cost-effective.
• Professional Team: Expert wind turbine guidance.
• High aerodynamic efficiency, low noise, corrosion resistance.
• Medium temp range: -20℃ to 80℃, ≤ humidity, ≤ 100mg/m3 dust content.
• Durable Fiberglass Build: Ensures long-lasting performance.
• Ethylene-based fiberglass blades optimize airflow.

Application

Structural features

Fans can be made into left-hand and right-hand rotation. Looking at the fan impeller from the transmission part, if it rotates clockwise, it is called Right rotation is indicated by "right"; if the impeller rotates counterclockwise, it is called left rotation, indicated by "left". This type of fan has single-side air intake and adopts V-belt drive. There are three machine numbers: No.4, No.4 3/4, and No.6. The fan is mainly composed of impeller, casing, transmission group, adjustment door, bracket, and other parts. The outlet angle can be made into three angles: 0°, 90°, and 180°.

1. The impeller is welded with arc-shaped backward-inclined blades, arc-conical front disc, and flat rear disc.
2. The casing is a volute casing welded with steel plates, and there is a foundation angle steel on the intake side to support the casing.
3. The transmission part consists of a main shaft, a water-cooled bearing box, and a pulley.
4. The adjusting door is installed on the front side of the air inlet to adjust the air volume.
5. The bracket is made of cast iron and is used to support the transmission group, and its bottom surface is in contact with the foundation.

Performance and Selection

The fan is given a dimensionless performance curve and its dimensionless performance is calculated according to the relevant formula. When in use, there is often a phenomenon of excessive or insufficient flow. There are many reasons for this phenomenon: if this phenomenon occurs during use, it is mainly due to the resistance in the pipe network being large or small, or the fan working in the flying area; if it is in use, it gradually decreases over a long period of time, or suddenly decreases in a short period of time, mainly due to pipe network blockage. After the fan is newly installed, it produces excessive or insufficient flow when it is running. The main reasons are as follows:

1. The actual value of the pipe network resistance is too different from the calculated value. According to the general pipe network characteristic equation p=Kq² (K is the resistance coefficient), if the actual value K is less than the calculated value K, the flow rate will increase; if the actual value K is greater than the calculated value K, the flow rate will decrease.
2. The influence of the fan's total pressure deviation Δp was not considered during selection. When the fan's total pressure value has a positive deviation, the flow rate increases; when the total pressure value has a negative deviation, the flow rate decreases.

When the fan starts to operate after being newly installed, or when the flow rate is too large or too small during use, one of the following methods can be used to eliminate it:

① Use the opening and closing degree of the regulating door to adjust the flow rate;
② Change the speed regulation of the fan;
③ Change the fan with higher or lower pressure to adjust the flow;
④ Change the pipe network resistance coefficient to adjust the flow rate.
 

It must be pointed out that throttling devices are generally used to adjust the flow rate. However, when the actual flow rate is much larger than the required flow rate, this method wastes too much electricity and is very uneconomical. If conditions permit, it is usually necessary to reduce the fan speed or replace the fan with a lower pressure. When the regulating door is fully opened, the flow rate is still too small. At this time, the pipe network should be changed to reduce the resistance coefficient to increase the flow rate. You can also increase the fan speed and replace the fan with a higher pressure, but the maximum fan speed cannot exceed the maximum speed on the performance table.
 

Fan performance - generally refers to the performance of conveying air under standard conditions. The specified state of the induced draft fan is atmospheric pressure P = 101300Pa, gas temperature t₀ = 200°C, gas density ρ₀ = 0.745kg/m³. The performances mentioned above refer to when the blades are fully opened to 0°. The performance table is used as the standard when ordering. When the actual use status does not match the above specified status, the performance of the actual use status must be converted to the performance of the specified status, and then the fan is selected based on the converted performance.