Causes of Damage to the Impellers of Explosion-Proof Centrifugal Fans

Causes of Damage to the Impellers of Explosion-Proof Centrifugal FansCauses of Damage to the Impellers of Explosion-Proof Centrifugal Fans: In the cement industry, fan blades in the raw material vertical mill recirculation system are frequently damaged. The function of explosion-proof centrifugal fans is to collect raw powder via cyclone dust collectors; the remaining small amount of raw powder is driven by recirculation fans to power electric dust collectors. Consequently, many fine gas-borne particles are carried along with the high-velocity gas stream. The recirculation fans accelerate the gas flow, causing continuous erosion of the blades. Over time, blade-like damage has occurred at both the inlet and outlet of explosion-proof centrifugal fans. This is because the damage forms an arc shape, causing the impeller to lose its balance. In other words, impeller damage is related to the composition of abrasive materials, particle size distribution, concentration, shape, impact velocity, impact angle, gas composition, properties, temperature, and ambient humidity. Asymmetry in gas flow within the impeller accelerates this damage. Methods to Prevent Impeller Damage in Explosion-Proof Centrifugal Fans. 1. To reduce flue gas and corrosive vapors in explosion-proof centrifugal fans, the software for the fan’s operating system needs to be updated. 2. Make the damage as symmetrical as possible. Therefore, it is necessary to improve the impeller’s wear resistance. Improving the impeller’s wear resistance involves selecting raw materials with high toughness and good wear resistance; this not only affects the impeller’s manufacturing process but is also impractical from an economic perspective. 3. Replacing the materials used in explosion-proof centrifugal fan impellers can extend the service life of the motor rotor. In addition to the materials’ processing and physical properties, attention must also be paid to their chemical properties. Stainless steel is the preferred material for impellers. When the chromium content in steel exceeds 12%, its corrosion resistance becomes exceptionally high. 4. Utilizing carbon nanotechnology with polymer materials for the repair and maintenance of polymer components. Since polymer technology combines special chemical fibers, ceramics, silicon steel, and other raw materials, it not only possesses very high compressive strength and tensile strength but also excellent corrosion resistance, making it suitable for use in extreme dry grinding environments. The results have far exceeded expectations. The performance of the refurbished explosion-proof centrifugal fan impeller is remarkably evident; it has resolved the fundamental issues of corrosion and damage to the impeller of the liquefied gas explosion-proof centrifugal fan motor, ensuring the normal operation of the generator and achieving significant economic and social benefits.