Emergency stop: major Electrostatic wet precipitator company In case of one of the following situations during the unit commissioning, emergency shutdown shall be carried out immediately. The emergency stop operation is to press the stop button of the main motor, and then carry out the remedial work after the shutdown; The centrifugal fan suddenly vibrates strongly and has exceeded the trip value; There is scratch or abnormal friction sound inside the machine body; major Electrostatic wet precipitator Smoke occurs at any bearing or seal, or the temperature of a bearing rises sharply to the alarm value; When the oil pressure is lower than the alarm value and cannot be restored to normal; The liquid level in the oil tank is low, and there is suction phenomenon; When the axial displacement value increases significantly and reaches the alarm value;
major Electrostatic wet precipitator Fans can be divided into axial flow fans, centrifugal fans and diagonal flow (mixed flow) fans according to the flow direction after the airflow enters the impeller. Fans are divided into press in local fans (hereinafter referred to as press in 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 (hereinafter referred to as extraction fans) according to their purposes. Electrostatic wet precipitator company Fans can also be divided into single-stage, two-stage or multi-stage pressurization fans according to the form of pressurization. For example, 4-72 is single-stage pressurization, and high-end fan is multi-stage pressurization fan. Fans can be divided into axial flow fans, mixed flow fans, roof fans, air conditioning fans, etc. Fan can be divided into negative pressure fan, low pressure fan, medium pressure fan and high pressure fan according to pressure. According to the outlet pressure (pressure rise), it can be divided into: ventilator (≤ 15000 Pa), blower (15-350000 Pa), compressor (≥ 350000 Pa)
Electrostatic wet precipitator company Forecast from the characteristics of fan demand. major Electrostatic wet precipitator For small and medium-sized fans with large usage and wide range, the product structure and manufacturing process are relatively simple, and the cost is also low. Users mainly pursue high efficiency, low noise, long life, and low price. The other is capital and technology intensive. The product structure is complex, the manufacturing cycle is long, and the completeness and systematicness are also strong. Moreover, it operates under high pressure, high temperature and high speed conditions, and some even operate under severe conditions. Users have different requirements for this type of fan. For turbine blowers, compressors and large ventilators, users mainly pursue high quality, high reliability, smooth operation and long cycle
Correct maintenance is an important guarantee for the safe and reliable operation of the fan and the improvement of its service life. Therefore, Electrostatic wet precipitator company When using fans, full attention must be paid. Impeller maintenance: at the initial stage of impeller operation and during all regular inspections, whenever there is an opportunity, the impeller must be checked for cracks, wear, dust and other defects. The impeller must be kept clean whenever possible, major Electrostatic wet precipitator The steel wire brush shall be used regularly to remove the dust and rust on the impeller. As the travel time increases, the dust can not be evenly attached to the impeller, which will cause damage to the balance of the impeller and even cause rotor vibration. As long as the impeller is repaired, it needs to be dynamically balanced again. If possible, the portable trial dynamic balancing instrument can be used for on-site balancing. Before dynamic balancing, check whether all fastening bolts are tightened. Since the impeller has been operating in an unbalanced state for a period of time, these bolts may have become loose. Bearing maintenance: frequently check the oil supply of bearing lubricating oil. If the box leaks oil, tighten the bolts of the end cover a little. If this is not enough, you may have to use new sealing packing. When the bearing lubricating oil is in normal use, it should be replaced at least once every six months. When it is used for the first time, it should be done after 200 hours of operation. The second oil change should be done in 1 to 2 months. After that, the lubricating oil should be checked once a week. If the lubricating oil does not deteriorate, the oil change can be extended to 2 to 4 months. The specified brand of lubricating oil (specified on the general drawing) must be used when replacing, The old oil in the oil tank shall be completely drained and cleaned before new oil can be filled. If the fan bearing needs to be replaced, pay attention to the following matters: before installing the new bearing, the bearing and bearing box must be very clean. Place the bearing in the oil with a temperature of about 70~80 ℃ and heat it before installing it on the shaft. Do not force assembly to avoid damaging the shaft. Maintenance of other supporting equipment: see the respective user manual for the maintenance of various supporting equipment, including motors, electric actuators, instruments, meters, etc. These operating instructions are provided by each supporting manufacturer. The manufacturer will pack these instructions together and provide them to the user
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 full 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. (
Fans can be classified into several types according to the materials used, such as iron shell fans (ordinary fans), glass fiber reinforced plastic fans, plastic fans, aluminum fans, stainless steel fans, etc. Electrostatic wet precipitator company In the direction of gas flow. Fans can be classified into centrifugal, axial, diagonal (mixed flow) and cross flow fans according to the direction of gas flow. (1) Centrifugal fan. The airflow enters the impeller of the fan axially and flows mainly along the radial direction. This type of fan is made according to the principle of centrifugal action, and its products include centrifugal fan, centrifugal blower and centrifugal compressor. (2) Axial flow fan. The airflow enters the impeller of the fan axially and flows approximately along the axis on the cylindrical surface. Such fans include axial fans, axial blowers and axial compressors. (3) Rotary fan. Ji'an major Electrostatic wet precipitator Use the rotor rotation to change the air chamber volume to work. Common varieties include Roots blower and rotary compressor.