FBCDZ series explosion-proof withdrawable counter-rotating axial-flow fans for coal mine ground (including FBCDZ54, FBCDZ60) (formerly BDK) are the most energy-saving axial-flow main fans at the current domestic level. It can be applied to coal mines and metal mines. The ventilation of chemical mines, tunnels, and civil air defense works can also be widely used for ventilation and ventilation in various industries such as metallurgy, chemical industry, textiles, and building materials. Structural features of the fan: 1.FBCDZ series fans are composed of current collectors, primary hosts, secondary hosts, diffusers, circular transformer joints, mufflers, diffusion towers and other components.The fan base is equipped with FBCDZ series coal mine grounds. Explosion-proof withdrawable counter-rotating axial-flow main fan wheels can be moved axially or non-axially on a preset track. Each component is bolted for easy maintenance. 2. The FBCDZ series fan adopts the direct connection of the motor and the impeller to reduce the loss of ventilation resistance such as the “S” air duct, improve the efficiency, and reduce the safety hazards and maintenance troubles caused by the “S” air duct, which improves the operational safety. . FBCDZ series explosion-proof withdrawable counter-rotating axial flow main fan for coal mine grounds3, the two-stage working impeller of FBCDZ series fan rotates in opposite directions, the first and second blades are guide vanes, and the amorphous guide vanes reduce the number of guide vanes. Energy consumption simplifies structure and improves efficiency. 4.The fan is equipped with a high-quality fan ** explosion-proof electric motor.The motor is placed in an isolating chamber with a certain pressure resistance, so that the motor and the mine contain gas. FBCDZ series of mine explosion-proof withdrawable counter-rotating axial flow main fan The wind flow is isolated, and the baffle cavity is provided with an air channel that is automatically ventilated to the atmosphere, which is convenient for heat dissipation and flow guidance. This not only increases the explosion-proof performance of the motor, but also facilitates the heat dissipation of the motor, thereby increasing the safety of the fan operation. 5. The rotating part of the fan impeller is equipped with a copper anti-friction device to prevent frictional sparks to prevent sparks from colliding with the cylinder wall during high-speed rotation and causing accidents. & FBCDZ; series explosion-proof withdrawable counter-rotating axial-flow main fan nbsp for coal mine grounds; 6. The fan is equipped with a brake device, which is convenient for reverse wind, and the reverse wind program can be completed in 5 minutes. The anti-air volume reaches more than 60% of the normal air volume, which complies with the requirements of the Safety Regulations. 7. The fan is equipped with non-stop refueling device and oil discharge device, which can be filled with lubricant during operation. When the machine is stopped, the oil outlet cover can be opened to eliminate waste oil. FBCDZ series coal mine ground explosion-proof withdrawable counter-rotating axial-flow main fan Guomao fan piping system refers to the total of all pipes and accessories, suction devices, and discharge devices of Guomao fan units except Guomao fan. The performance curve of the Guomao fan pipeline refers to the relationship curve between the total energy (that is, the total pressure) required for a unit volume of gas to be sent from the suction space through the pipeline and accessories to the pressure space, and the flow rate Q of the pipeline system. Generally, the suction space and the pressure space are both atmospheric, and the gas level energy is usually ignored.The mathematical expression of the pipeline performance curve is (N / ㎡) (4-28) where the comprehensive resistance coefficient of the pipeline system ( ㎏ / ㎡). It depends on the resistance characteristics of the piping system, and is determined based on the piping system's setting and resistance calculation. The pipeline performance curve represented by formula (4-28) is a quadratic parabola passing through the origin in the coordinate system. The calculation formula of the specific rotation speed of Guomao Fan is the high-pressure shaft circulation. Guomao Fan: The full-pressure Guomao fan piping system refers to all the pipes and accessories of the Guomao fan unit except the Guomao fan, suction device, and discharge device. sum. The performance curve of the Guomao fan pipeline refers to the relationship curve between the total energy (that is, the total pressure) required for a unit volume of gas to be sent from the suction space through the pipeline and accessories to the pressure space, and the flow rate Q of the pipeline system. Generally, the suction space and the pressure space are both atmospheric, and the gas level energy is usually ignored.The mathematical expression of the pipeline performance curve is (N / ㎡) (4-28) where the comprehensive resistance coefficient of the pipeline system ( ㎏ / ㎡). It depends on the resistance characteristics of the piping system, and is determined based on the piping system's setting and resistance calculation. The pipeline performance curve represented by formula (4-28) is a quadratic parabola passing through the origin in the coordinate system. In the application of Guomao fans, in addition to meeting the requirements for its flow and wind pressure, the requirements for efficient operation of Guomao fans should also be considered, which is an important factor for the reasonable selection of Guomao fans. The performance of Guomao fans is the basis for the reasonable selection of Guomao fans. The expression methods of Guomao fans are different, and the selection methods of Guomao fans are also different. The dynamic pressure of Guomao Fan is defined as the dynamic pressure of Guomao fan outlet, that is, (4) the method used to determine the selection of Guomao fan according to the product samples of Guomao fan (i.e. performance table, performance curve, dimensionless performance curve, performance selection curve) in**). In general, the specific revolution of Guomao Fan should be calculated according to the selection parameters of Guomao Fan, which is more conducive to the reasonable selection of Guomao Fan. Guomao fan performance is the second control condition of Guomao fan selection. Care should be taken in selecting the Guomao fan with higher efficiency, and the Guomao fan should be operated in a high-efficiency work area; when possible, the Guomao fan with high speed and small impeller diameter should be selected. For systems with small loads and simple working conditions, the Guomao fan can be selected at one time; for systems with larger loads and more complicated working conditions, it is often necessary to perform performance comparison and comprehensive analysis between different models of Guomao fans to Determine the most reasonable Guomao fan model. In addition, in the selection of Guomao fans, it should be avoided as much as possible. For example, the saddle-shaped performance curve is the main reason for the abnormal operation of Guomao fans, such as rotational deflow, surge, and windbreaking. It should be paid attention to when selecting Guomao fans. In the formula:-speed (rpm); Q-flow (㎡ / s);-full pressure (mmH2o) of Guomao fan under standard conditions. Rotor static imbalance and dynamic imbalance Guomao fans and motors have the same consistent vibration. The vibration frequency and speed are consistent. 1. The shaft and the seal ring are subject to intense friction, which generates local high heat and bends the shaft. 2. The quality of the blade is asymmetric, or one side of the blade is severely corroded or worn. 3. The blade has uneven attachments, such as rust, ash or tar. 4. The quality and position of the balance weight are incorrect, or the position is moved, or the balance is not found after the maintenance. 5. The Guomao fan operates under unstable conditions (ie, the flying area), or the load changes sharply. 6. The air intake volume on both sides of the double-suction Guomao fan is not the same (due to blocked pipes or improper adjustment of the air inlet baffles on both sides) 1. The shaft should be replaced with a new one, and the seal ring needs to be repaired at the same time. 2. Replace the bad blades or replace the new impeller and find balance. 3. Sweep or clean up the attachments on the leaves. 4. Find the balance again and fix the balance weight firmly. 5. Open the gate valve or bypass valve to adjust the condition. 6.Clean the dust in the intake duct, and adjust the baffle so that the negative pressure on the air inlets on both sides is equal. The bad vibration of the shaft installation is uncertain, light when idling, and large at full load (can be detected by reducing the speed) 1.Coupling Improper installation, the center of Guomao fan shaft and motor shaft are not aligned, and the foundation is lowered. 2. The installation of the pulley is incorrect, and the two pulley shafts are unbalanced. 3. When the reducer shaft is aligned with the Guomao fan shaft and the motor shaft, the compensation for displacement during operation is not considered, or although it does not meet the requirements 1. Adjust and re-align. 2. Make adjustments and re-adjust. 3. Make adjustments to allow for a proper displacement compensation margin. Four: There are two reasons for the failure of the Guomao fan during operation. There are two ways to introduce gas into the impeller. One is to directly inhale from the atmosphere, which is called free intake; the other is to use an air intake pipe or an intake box to intake air. . No matter which type of air intake, it is necessary to install an inlet collector in front of the impeller. The role of the current collector is to ensure that the airflow can be evenly distributed on the section of the impeller inlet, reach the speed value required by the inlet, and enter the impeller with minimal airflow loss. The current collector forms are cylindrical, conical, arc, cone-cylinder and cone-arc, etc., as shown in Figure 4-2. The arc shape and the conical arc shape have good performance. They are adopted by large Guomao fans to improve the efficiency of Guomao fans. High-efficiency Guomao fans basically use cone-arc collectors. The change lags behind the unstable change of Guomao's fan operation, so the pipeline pressure remains unchanged as shown in Figure 4-17. In the condition that the Guomao fan has no flow output and the pipeline pressure is greater than the pressure of the Guomao fan, the Guomao fan has a forward rotation and reverse flow phenomenon, and the Guomao fan jumps to point C to work. Due to the pressure drop of the pipeline flow output, the reverse flow also decreases, and the Q-P performance of the Guomao fan changes along the CD line. At point D, the pipeline pressure is equal to the pressure of the Guomao fan, and the reverse flow is also equal to zero.The Guomao fan has no output and no flow input, but the Guomao fan is still running continuously. Jump to point E. However, since the external air volume is still maintained, the above process will be repeated periodically in the order of E-K-C-D-E. The above discussion is also an analysis of the surge mechanism.