1, the pipeline ventilator selection control parameters for the air volume, full pressure, efficiency, noise, motor power and so on.
2, according to the physical and chemical properties of the gas being transported, choose a different purpose of the ventilator. Such as conveying clean air, should choose a general ventilator; conveying flammable, explosive gases, should choose explosion-proof ventilator; conveying corrosive gases, should choose corrosion-resistant fan.
3, ventilator selection, should take into account the piping system leakage loss, calculation error, and the actual air volume of the ventilator, the wind pressure of the negative deviation, the general use of the air volume of 1,05 ~ 1,1, the wind pressure of 1,10 ~ 1,15 safety factor. But not too large, in order to prevent the ventilator long-term operation in the low efficiency zone.
4, pay attention to the resistance characteristics of the pipe network and the matching relationship between the characteristics of the ventilator. In order to make the ventilator can run stably, should make the ventilator in its highest efficiency point near the work, the working point of the ventilator is located in the performance curve in the full pressure peak point of the right (that is, the side of the air volume, and is generally located in the peak of the full pressure of 80%).
5, on the muffling requirements of the ventilation system, should be the first choice of high efficiency, low impeller circumferential velocity of the ventilator, and make it work near the highest efficiency point. Should also be based on the ventilation system to produce noise and vibration propagation mode, take corresponding muffling and vibration reduction measures.
6, pipeline ventilator is through the blade shape change, so that the airflow into the fan, both part of the axial flow, and produce part of the centrifugal effect, so its performance between the axial fan and centrifugal fan.
7, duct ventilator can provide medium wind pressure and medium air volume, used in high-rise civil buildings in the ventilation system are more appropriate.
Second, the working principle of circular duct fan
Circular duct fan adopts wing-shaped backward tilting impeller, the high speed operation will be the gas hydrodynamics to play to the extreme, so the energy-efficiency ratio is very high, it can reach 70%, that is to say, with the smallest motor power to deliver the maximum wind, which is the ordinary forward centrifugal fan can not achieve the effect. Therefore the duct fan is both energy efficient and windy. Ultra-high wind pressure can be connected to dozens of meters of pipeline centralized ventilation, the main feature of the pipeline fan is high pressure. Replaces the traditional ventilation equipment. Fan without vibration, dynamic balance value is less than 0.17g, only such a standard value to ensure the superior quality of the fan, imported metal impeller supporting or PP plastic in accordance with the wing type infused and become, which is characterized by strong rigidity, high temperature resistance, environmental protection, large air volume, and can be a certain degree of noise reduction.
Circular duct fan inner core adopts outer rotor motor, its life depends on the bearing, the motor adopts imported single-row deep groove ball bearings, outer rotor motor's structure is compact, small volume, energy saving and high efficiency, pure imported bearings supporting, 120 ℃ automatic stopping thermal protection, high-quality copper wire winding and so on. It can run continuously 24h non-stop for more than 30,000 hours.
Three, installation points
1, ventilator installation pedestal (foundation, hanger) should have sufficient strength, stability and durability, pedestal vibration should meet the following provisions:
1) The self-vibration frequency of the foundation device shall not be greater than 1/3 of the speed of the motor and the ventilator.
2) The difference between vibration speed of the ventilator in operation and that of the ventilator in rest shall be greater than 3 times. The difference between the vibration speed when the ventilator is running and the vibration speed when the ventilator is at rest should be more than 3 times.
2, the ventilator import and export and the connection between the duct, should be set up flexible joints. Inlet ducts, outlet ducts and other devices should be supported separately and firmly supported by the foundation or other components of the building, the casing should not bear the weight of other parts.
3, ventilator installed in the building components, vibration isolation measures should be taken.
4. The installation of the ventilator can be carried out with reference to the following national building standard design drawings.
5, duct ventilator can be installed on the straight duct.