River pool Electrostatic wet precipitator 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) major Electrostatic wet precipitator 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) Electrostatic wet precipitator Price 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
Preparations for fan installation. major Electrostatic wet precipitator Before unpacking the fan, check whether the package is intact, whether the nameplate parameters of the fan meet the requirements, and whether all accompanying accessories are complete. Carefully check whether the fan is deformed or damaged during transportation, whether the fasteners are loose or fall off, and whether the impeller is scratched, and check all parts of the fan. River pool Electrostatic wet precipitator Price If any abnormality is found, it shall be repaired before use. Use a 500V megger to measure the insulation resistance between the fan housing and the motor winding. The value should be greater than 0.5 megohm. Otherwise, the motor winding should be dried. The temperature during drying should not exceed 120 ℃. Prepare various materials, tools and sites required for fan installation.
River pool major Electrostatic wet precipitator Forecasts from foreign markets. The member units of China General Machinery Fan Industry Association exported 7969 fans in 2000, with the export delivery value of 81.157 million yuan. From 1991 to 2000, the total number of exported fans was 72876, and the total value of export delivery was 747.26 million yuan. Electrostatic wet precipitator Price The trend of global economic integration is becoming more and more obvious. The economies of all countries will further depend on each other. International economic cooperation and exchanges will become closer and closer. The international market is at a stage of significant intersection and integration. At the same time, the pace of global industrial restructuring is accelerating, and significant progress has been made in the scale and depth of international division of labor. Developed countries continue to shift industrial production to capital intensive and technology intensive industries, and labor-intensive products are transferred to developing countries and regions. This provides a good development opportunity for China to play its own advantages and enter the international market. Since the 1970s, China has introduced foreign advanced technology of centrifugal compressor, which has improved the product grade through digestion, absorption and innovation. As long as the quality and delivery time are guaranteed and the price advantage is used, it is competitive internationally. Especially after China's entry into WTO, it is entirely possible to increase the fan export. From the historical analysis, the main export varieties are small and medium-sized fans and fan accessories. The main gap between domestic enterprises producing such fans is that the surface quality cannot meet the export requirements. If the appearance quality is improved and the price is favorable, the prospect in the foreign market is broad. From 1991 to 2000, the fan exports of small and medium-sized fans were not stable enough, and there was no obvious growth trend. However, with the continuous progress of technology, it is expected that the export volume of such fans will continue to increase, and it is predicted that the annual average growth rate will be about 5% on the basis of 2000. major Electrostatic wet precipitator The export of centrifugal compressors and blowers increased significantly from 1991 to 2000, reaching 870000 sets in 2000. The main exporting countries are India, Pakistan, Iran, Vietnam and other developing countries. It is expected that this trend will continue to develop, reaching 1 million units per year.
Emergency stop: major Electrostatic wet precipitator Price 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;
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.