2. The influence of the total pressure deviation Δ H of the fan itself was not considered during selection. When the actual total pressure of the fan was positive deviation, the flow increased; When the actual total pressure of the fan is negative deviation, the flow decreases. See (a) below. The relationship between the deviation of the pipe network characteristic curve and the total pressure and the flow can be eliminated by one of the following methods when the fan starts to officially operate after new installation, or when the flow is too large or too small during use. 1. Use the opening and closing of throttling device to adjust the flow. 2. Increase or decrease the flow by increasing or decreasing the fan speed. 3. Use a new fan with higher or lower pressure to increase or decrease the flow. 4. Change the pipe network to reduce the resistance coefficient of the pipe network to increase the flow. It must be pointed out that throttling devices are generally used to regulate the flow. However, when the actual flow is much larger than the required flow, this method wastes too much power and is very uneconomical. If conditions permit, the fan speed is usually reduced or the fan with lower pressure is replaced. When the throttling device is fully open, the flow is still too small. At this time, the throttling device has lost its function, so try to reduce the resistance coefficient of the pipe network to increase the flow, or increase the fan speed and replace the fan with higher pressure. However, the speed of the fans directly connected to the motor and the coupling cannot be changed generally. Only the fan driven by the pulley can increase or decrease the speed by changing the diameter of the pulley, but the speed of the fan cannot exceed the speed max in the performance and selection table.

Xi'an Axial flow fan Classified by layers. There are many classification methods for fans, which can be roughly classified according to the following levels: (1) According to the level of pressure generated, they can be divided into: volumetric: reciprocating and rotary; Turbine type: centrifugal, axial flow, mixed flow and cross flow, jet type. Fan generally refers to turbine type, namely centrifugal, axial, mixed flow, cross flow and other forms. Its main characteristics are: centrifugal fan: higher pressure, but smaller air volume. Axial flow fan: higher air volume, but lower pressure. Mixed flow fan: the air volume and pressure are between centrifugal fan and axial fan. Horizontal fan: with high dynamic pressure, it can obtain flat airflow. (2) large Axial flow fan According to the different materials used, it can be divided into:; Iron shell fan (ordinary fan), glass fiber reinforced plastic fan, plastic fan, aluminum fan, stainless steel fan, etc. (3) According to the direction of gas flow, it can be divided into centrifugal type, axial flow type, diagonal flow type (mixed flow type) and cross flow type. (4) According to the flow direction of the airflow entering the impeller, it can be divided into axial flow fan, centrifugal fan and diagonal flow (mixed flow) fan. (5) Axial flow fan company It can be divided into: press in local fans and flame-proof motors placed outside or inside the flow channel, and flame-proof motors placed inside the explosion-proof sealing chamber of the extraction type local fans. (6) According to the form of pressurization, it can also be divided into single-stage, two-stage or multi-stage pressurization fans

Wet dust remover is a device that uses the action of water or other liquids and dusty gases to remove dust particles. When dust particles meet with sprayed water droplets, water films or wetted walls and devices The process of wetting, condensation, diffusion and sedimentation takes place, so it is separated from the gas to purify the gas. Xi'an Axial flow fan company It is characterized by purifying dust at the same time It can also purify gas, large Axial flow fan When the flue gas contains combustible components, the use of wet dust collectors can avoid equipment explosion, and the dust removal effect can generally meet the environmental protection requirements. The equipment is small and the investment is relatively low. Therefore, there are three wet dust collectors used in dust removal projects in mining, metallurgy, machinery, light industry, building materials and other industries. Sludge containing sewage must be treated, otherwise secondary pollution may occur, Therefore, it is not widely used as dry dust collector. There are many types of wet dust collectors. According to their structures, there are the following types: ① gravity spray wet dust collectors - spray scrubbing towers; ② Cyclone wet dust collector - cyclone water film dust collector, water film dust collector; ③ Self excited wet dust collector - impulse dust collector, water bath dust collector; ④ Packed wet dust collector - packed tower, turbulent ball tower; ⑤ Foam wet dust collector - foam dust collector Cyclone dust collector, leaky plate tower; ⑥ Venturi wet dust collector - Venturi tube dust collector; ⑦ Mechanical induction wet dust collector - water wheel dust collector.

large Axial flow fan The reasons for failure caused by unstable operation are: improper temperature control of insulator box; The gas distributor grid is blocked, and the sediment electrode has too thick scale; Improper adjustment of water film; The oxygen content in the system exceeds the standard. ① Insufficient steam pressure and blocked steam pipeline may cause low temperature of insulator box. In the long run, the insulator surface temperature is low, and tar and dust particles accumulate, causing electric field short circuit. If the temperature of insulator box rises too fast, or the temperature changes violently during operation, the insulator will be cracked. ② Axial flow fan company If intermittent flushing cannot be carried out as required during operation, the tar accumulated on the sediment pipe wall is difficult to be thoroughly cleaned, which, accumulated over time, not only causes excessive resistance to equipment operation, but also leads to damage to the electric field. ③ During maintenance, the water film is not adjusted as required, the water film is uneven or not thick enough, and after putting into operation, the phenomenon described in fault (4) will occur. The above situation also occurs when the water film is damaged during operation. ④ The reason for the explosion of the electrostatic precipitator is that the oxygen content in the gas exceeds the standard, the mixed explosive gas is formed in the equipment and reaches the explosion limit, and the explosion occurs when encountering electric sparks.

Selection and application of fan performance (I) Description of fan performance: 1. № 10, 12, 16, 20 are converted according to dimensionless performance of № 10 model. 2. № 5, 6, 8 are converted according to dimensionless performance of № 5 model. 3. № 5 and below shall be determined according to the performance of the measured prototype. Note: According to the dimensionless performance curve conversion formula, total pressure H=ρ u2 H (Pa) flow Q=900 π D22 uQ (m3/h) shaft power N=N × D22u3 ρ/4000 (kw), where D2 - impeller outer diameter (m) u - impeller outer edge linear speed (m/s) ρ - gas density (Kg/m3), the required power rate shall be based on shaft power plus mechanical loss and motor reserve. 4. The solid line is № 5 model, and the dotted line is № 10 model. The performance of the fan is expressed by the flow, total pressure, main shaft speed, shaft power, efficiency and other parameters of the fan, and there are certain relationships between the parameters, which are listed in the following table. The relationship of fan performance parameters changes density ρ, speed n changes speed n, atmospheric pressure P, gas temperature t Q1/Q2=n1/n2 H1/H2=(n1/n2) 2 ρ 1/ρ 2 N1/N2=(n1/n2) 3 ρ 1/ρ 2 η 1=η 2 Q1/Q2=n1/n2 H1/H2=(n1/n2) 2 (P1/P2) (273+t2/273+t1) N1/N2=(n1/n2) 3 (P1/P2) (273+t2/273+t1) η 1=η 2 Note: 1. In the middle, Q represents flow (m3/h), H represents total pressure (Pa), N Represents shaft power (kw), η represents total pressure efficiency, ρ represents density (kg/m3), t represents temperature (℃), n represents speed (r/min), and P represents atmospheric pressure (Pa). 2. The footnote symbol 2 indicates the known performance and related parameters, and the footnote symbol 1 indicates the required performance and related parameters. （

Axial flow fan company In the use of wet electrostatic precipitator, we will encounter problems of one kind or another. If we do not know how to solve them, we will not know what to do. What are the reasons for the failure of wet electrostatic precipitator? Next, I will analyze it for you. （1） large Axial flow fan The causes of electrical failure include: electrical components are damaged, corona electrode is not adjusted properly, and porcelain bushing and post insulator through the wall are damaged. ① The electrical components are damaged, such as the fuse is blown, the high-voltage silicon rectifier tube is broken down or the thyristor is damaged, which can lead to the power failure; If the milliammeter is damaged or the transformer fails, the phenomenon of fault type (3) will occur. ② If the nickel chromium alloy wire is not used, the corona electrode will be rusted and broken after being used for a short time. The tension of corona wire is uneven, the force is uneven, and the overload of individual corona electrode will also cause the corona electrode to break; If the corona electrode is not installed in place, deviates from the center of the settling tube, or has too much scale, the electric field will flash over frequently, or even the operation will be interrupted. ③ If the mechanical properties of the through wall porcelain bushing and post insulator are not up to standard and cannot bear the tension of the upper and lower hangers, the insulator will be damaged and cracked. The insulator box temperature control is unreasonable, and the temperature is low or changes violently, which will also cause the insulator to be damaged and cracked; Excessive scale on the surface of insulator will also cause damage and crack of insulator. The final result is that the electric field is grounded, the operation of the electrostatic precipitator is interrupted, and faults (2) and (4) occur.