4-79-10CStainless steel fan

Use
4-79 type centrifugal fan can be used for indoor ventilation in general factories and large buildings, it can be used to input gas, can also be used to output gas species transport gas for air or other combustion, not exploding, no winding, the gas harmless and non corrosive to steel materials. There is no viscous substance in the gas, the dust and hard particles are not more than 150mg/m3. The temperature of the gas shall not exceed 80 DEG C.
Type
The fan can be made to rotate clockwise or counter clockwise two types. From one end of the motor face, the clockwise rotation of the impeller is called clockwise, in order to "Shun", or vice versa, said that the "inverse" said.
Structure
4-79 fan in No. 3A - 6A is mainly composed of a casing, impeller, air inlet, motor. No 7C 20E is in addition to the part, and the transmission part.
The impeller is composed of a thin plate with a back arc, a curved front plate and a flat rear plate, which are made of steel plate and adjusted by the static and dynamic balance. The utility model has the advantages of good air performance, high efficiency, low noise and stable operation. No. 3, No. 3.5 consists of 12 blades, No. 4, No. 4.5 consists of 14 blades, no more than 5 by 16 pieces.
A - made of two different types, No. 3 - 12 for housing as a whole, they cannot be separated; No. 14 - 20 of the housing made of two open along the horizontal plane is divided into two halves, by bolts.
The air inlet is made into a whole, and is arranged on one side of the fan, and the parallel cross section of the axial direction is a curve shape.
Driven by spindle, bearing box, rolling bearing, pulley.
Performance and selection
(1) the performance of the fan: the performance of the fan to air volume, total pressure, spindle speed, shaft power and power parameters, and there is a certain relationship between the parameters, these relations are as follows:
Change the conversion type density, speed of n:
ETA 1= 2.
Conversion of N, atmospheric pressure Pa, gas temperature t:
ETA 1= 2.
Type: Q (m3/h) - P - flow density (kg/m3)
P - full pressure (Pa) n - rotational speed (r/min)
P - power (KW) T - temperature (c)
ETA - efficiency (%) Pa atmospheric pressure (Pa)
Note: footnote symbol "2" indicates a known performance parameter, and the footnote symbol "1" indicates the desired performance parameter.
Fan performance generally refers to the standard conditions of the performance of the fan, regardless of technical documentation or order requirements in addition to the performance of special orders, according to the standard conditions prevail.
Standard status refers to the atmospheric pressure Pa = 101325Pa, atmospheric temperature t=20, relative humidity phi = 50%, P = 1.2kg/m3 air density, acceleration of gravity g=9.8m/s2.
Calculation of required power:
= P
Type: Q flow (m3/h) mechanical efficiency m (%), press the table selection
P - full pressure (Pa) K - motor capacity safety factor, according to table selection
ETA - efficiency (%)
(2) the selection of fan: the fan performance product performance and selection of parts included in the mean performance of air in standard condition, the performance when using the standard of performance conversion of non standard condition when, then press the performance table selection.
Mechanical efficiency
Drive mode
Motor direct coupling
Installation and commissioning
When in use, often too much traffic or insufficient, which is mainly due to network resistance when small, or fan in the flying area and other reasons:
If it is in the course of use, after a long time gradually reduced, or a sudden decrease in a short period of time, mainly due to network congestion.
In the new installation of the fan, the operation occurs when the flow of excessive or insufficient phenomenon, the main reasons are the following:
1, the actual value of pipe network resistance and calculated value is too large. From the general pipe network characteristic equation P = KQ2 can be seen, such as the actual value of K is less than the calculated value, the flow increases, otherwise the flow is reduced, see Figure 1a.
2, the choice of the fan does not consider the full pressure deviation value P. When the fan full pressure is positive deviation, the flow increases, otherwise the flow is reduced, see Figure 1b.
Too large or too small traffic can be eliminated by one of the following methods:
1, the use of energy-saving device adjustment.
2, change the fan speed regulation.
3, replace the pressure is higher or lower fan adjustment.
4, change the pipe network resistance coefficient adjustment.
It must be pointed out that the throttling device is used to regulate the flow rate. However, when the actual flow is much greater than the need for a large amount of traffic, this method is too much power waste, such as conditions permit, usually used to reduce the speed of the fan or replace the lower pressure fan.
When the throttle device is fully opened, traffic is still too small, the throttling device is disabled, should try to make the drag coefficient is reduced, in order to increase the flow, also can increase the fan speed or replace high pressure, but the fan motor and direct coupling are generally not only change the speed belt drive the fan can be changed by the diameter of the belt wheel to change speed, pay attention to the maximum speed fan can not exceed the maximum speed performance table.
No. 10 to 20 according to the dimensionless performance calculation model of No. 10, No. 5 to No. 8 by 5 dimensionless performance conversion model.
A formula for calculating the dimensionless parameters from dimensionless parameters:
P= P U2 (Pa) Q = 900 psi Phi PI D22u (m3/h)
P = (KW)
Formula: P - full pressure (Pa) P - axis power (KW)
D2 - impeller outer diameter (m) - power factor
U - impeller blade edge line velocity (m/s)
The required power should be according to the shaft power plus the mechanical loss and motor reserve.
Distance between the shaft end and the outer end of the fan belt pulley (mm)
Fan pulley A2 B4 D5 D7 E7 C4 E9
S 0005693145194
Ordering instructions
When ordering, the number, speed, air volume, pressure, outlet angle and rotation direction of the fan, as well as the motor model specifications shall be indicated.