Installation Method for the Seal Between the Drive Shaft and Housing of High-Temperature Fire-Rated Axial Flow Fans

Installation Method for the Seal Between the Drive Shaft and Housing of High-Temperature Fire-Rated Axial Flow Fans

During the design and manufacturing stages of high-temperature fire-rated axial flow fans, no seals are typically installed between the housing and the drive shaft because seals are not required. This is because this section operates under negative pressure during fan operation. Although there is no air leakage, the fan continues to operate. However, due to factors such as deformation of the ductwork, changes in resistance, or changes in the medium, it becomes necessary to install a seal in the shaft bore of the housing to prevent gas leakage. Currently, there are two options available. Option 1: Remove the housing of the high-temperature fire-rated axial flow fan, take off the propeller, disassemble the drive unit, and install a new seal ring or mechanical seal. The advantage of this method is the ability to select a new seal type and perform a standard installation; the disadvantage is that it involves significant labor and takes time. Option 2: Without disassembling the high-temperature fire-rated axial flow fan, add a simple packing assembly. Each packing assembly consists of a packing section, two stamped parts, and four semicircular components. First, place two workpieces marked with the outer cover on the shaft, then weld the grooves to the bearing housing to form a ring. Next, place two semicircular workpieces without the outer cover on the drive shaft and weld the grooves to form a circular ring. Pass the drive shaft through the two rings, with the grooves facing opposite directions. The ring marked with the sleeve is welded to the sleeve. Please note the clearance between the inner ring and the drive shaft. Next, weld the hex heads of the bolts from the two stamped parts to the housing, press one end of the stamped parts onto the ring, cut the sealing ring, and wrap it around the groove. Tighten the ring and tighten the nuts on the compression section. Compress one end of the ring, and install the recommended seamless sticker as normal. This method requires only initial preparation, with minimal subsequent installation work, making it suitable for high-temperature fire-rated axial fans that do not require sealing.