Installation Precautions for Low-Noise Fire-Rated Cabinet-Type Centrifugal Fans

Installation Precautions for Low-Noise Fire-Rated Cabinet-Type Centrifugal Fans

Low-noise fire-rated cabinet-type centrifugal fans are now widely used. As high-quality fan products, what precautions should be taken when installing these units? Low-noise fire-rated cabinet-type centrifugal fans 1. The low-noise fire-rated cabinet-type centrifugal fan must be placed directly on the foundation, using two shims to ensure it is level. 2. For low-noise fire-rated cabinet-type centrifugal fans assembled on-site, the cut surfaces of the base must be properly protected to prevent rust or damage. When placing the base on the foundation, use shims to ensure the base is level. 3. When assembling the main shaft and bearing sleeves, inspections must be conducted in accordance with the equipment technical documentation. The interference fit between the bearing cover and the bearing housing must be 0.03–0.04 mm (measured between the outer diameter of the bearing housing and the inner diameter of the bearing seat). 4. Securely connect the bearing housing and base of the low-noise fire-rated cabinet-type centrifugal fan, ensuring that longitudinal runout does not exceed 0.2/1000. Measure using a spirit level on the main shaft. The runout tolerance must not exceed 0.3/1000. Use a spirit level to measure the horizontal alignment of the bearing housing surfaces. 5. For low-noise fire-rated cabinet-type centrifugal fans assembled with rolling bearings, after installing the rotor, the bearing bores of the two bearing housings should be offset so that the rotor can rotate freely. 6. Before grinding the bearing sleeves, the rotor shaft and housing shaft must be aligned, and the clearance between the impeller and the inlet, as well as the clearance between the main shaft and the rear shaft bore, must be adjusted. The housing must be adjusted to meet the requirements specified in the equipment’s technical documentation. 7. When aligning the low-noise fire-rated cabinet-type centrifugal fan, the misalignment between the fan shaft and the motor shaft must not exceed 0.05 mm in the radial direction, and the angular misalignment must not exceed 0.2/100. 8. When assembling the housing, the housing’s position must be based on the rotating shaft. The axial and radial clearances between the impeller and the housing inlet must comply with the equipment’s technical documentation. At the same time, verify that the anchor bolts are securely tightened. When clearance values are not specified in the equipment’s technical documentation, the axial clearance is typically 1/100 of the impeller’s outer diameter, and the radial clearance must be evenly distributed. That value must be between 1.5/100 and 3/1000 of the propeller’s outer diameter (one of these values). When adjusting, reduce the clearance value to improve the efficiency of the low-noise fire-rated cabinet-type centrifugal fan.