Analysis of Wear Issues in the Drive System of the 919 High-Pressure Centrifugal Fan
The 919 high-pressure centrifugal fan operates on the principle of using a high-speed rotating impeller to accelerate, decelerate, and alter the direction of flow, thereby converting kinetic energy into potential energy (pressure). In the 919 high-pressure centrifugal fan, gas enters the impeller axially. After passing through the impeller, the gas undergoes a radial change and enters the diffuser. Within the diffuser, both the direction of gas flow and the cross-sectional area change. As the duct cross-section increases, the gas flow slows down.
Through this deceleration, kinetic energy is converted into pressure energy. The increase in pressure is primarily generated by the impeller and occurs during the diffusion process. Essentially, it functions as a variable-flow, constant-pressure device. Under steady-state conditions, it produces a constant pressure-flow relationship. The theoretical curve of a 919 high-pressure centrifugal fan must be a straight line. However, due to internal losses, the actual characteristic curve is curved. The pressure generated by the 919 high-pressure centrifugal fan is influenced by the temperature or density of the inlet air. These variations can have a significant impact.
Compared to the specified intake volume, the pressure generated is lower when the gas temperature is high (and air density is low). For a given pressure and flow characteristic curve, there is a corresponding power-flow characteristic curve. When the blower operates at a certain speed, the power required increases as the inlet air temperature decreases relative to a given flow rate.
Wear issues include wear on the transmission components of the 919 high-pressure centrifugal blower, as well as general equipment problems such as the bearing positions, bearing sleeves, and bearing shafts. If the 919 high-pressure centrifugal fan exhibits the above issues, traditional maintenance methods include surface finishing and thermal spray coating. However, all of these methods have specific drawbacks: they cannot completely eliminate the thermal stress caused by high temperatures during repair welding, which can easily lead to material damage, component warping, or failure; brush plating is limited by coating thickness and is prone to peeling.
The 919 high-pressure centrifugal fan operates on the principle of using a high-speed rotating impeller to accelerate, decelerate, and alter the direction of flow, thereby converting kinetic energy into potential energy (pressure). In the 919 high-pressure centrifugal fan, gas enters the impeller axially. After passing through the impeller, the gas undergoes a radial change and enters the diffuser. Within the diffuser, both the direction of gas flow and the cross-sectional area change. As the duct cross-section increases, the gas flow slows down.
Through this deceleration, kinetic energy is converted into pressure energy. The increase in pressure is primarily generated by the impeller and occurs during the diffusion process. Essentially, it functions as a variable-flow, constant-pressure device. Under steady-state conditions, it produces a constant pressure-flow relationship. The theoretical curve of a 919 high-pressure centrifugal fan must be a straight line. However, due to internal losses, the actual characteristic curve is curved. The pressure generated by the 919 high-pressure centrifugal fan is influenced by the temperature or density of the inlet air. These variations can have a significant impact.
Compared to the specified intake volume, the pressure generated is lower when the gas temperature is high (and air density is low). For a given pressure and flow characteristic curve, there is a corresponding power-flow characteristic curve. When the blower operates at a certain speed, the power required increases as the inlet air temperature decreases relative to a given flow rate.
Wear issues include wear on the transmission components of the 919 high-pressure centrifugal blower, as well as general equipment problems such as the bearing positions, bearing sleeves, and bearing shafts. If the 919 high-pressure centrifugal fan exhibits the above issues, traditional maintenance methods include surface finishing and thermal spray coating. However, all of these methods have specific drawbacks: they cannot completely eliminate the thermal stress caused by high temperatures during repair welding, which can easily lead to material damage, component warping, or failure; brush plating is limited by coating thickness and is prone to peeling.
