Please ask for advice on problems encountered in actual work~~~bearings~~~

Regarding your two questions, my views are as follows: Let’s first look at the description of back-to-back and face-to-face. A. The load lines of bearings paired back-to-back are separated toward the bearing shaft. It can withstand axial loads acting in two directions, but the load in each direction can only be borne by one bearing. Bearings mounted back to back provide a relatively rigid bearing arrangement and can withstand overturning moments. B. The load lines of bearings paired face to face converge towards the bearing shaft. It can withstand axial loads acting in two directions, but the load in each direction can only be borne by one bearing. This configuration is not as rigid as a back-to-back pairing and is less suitable for withstanding overturning moments. The rigidity and ability of this configuration to withstand overturning moments are not as good as the configuration. The bearings can withstand bidirectional axial loads. ； Attached pictures: Back-to-back and face-to-face It can be seen that the back-to-back installation can withstand the largest load and bearing moment and has the best axial positioning. ； There is a certain axial clearance when facing each other and the load is small, so the most commonly used one is back-to-back installation. This type of bearing is provided to users in pairs by the manufacturer according to certain preload requirements. Therefore, Harkon's air coolers are also pre-installed. So if you want to change, you need to pay attention to two points.: 1. Check whether it is suitable for installation and disassembly. 2. The axial force is mainly important, but it must bear a certain radial force. In comparison, back-to-back can bear more radial force, while face-to-face can bear axial force better and will not bend the shaft, but it can bear very little radial force. C. The second question is to first look at the definition of series. In series configuration, the load lines are parallel, and the radial and axial loads are evenly shared by the bearings. However, the bearing set can only bear axial load acting in one direction. If axial loads act in opposite directions, or if there are compound loads, a third bearing must be added that is adjusted relative to the tandem bearing. This configuration can also connect three or more bearings in series at the same support, but it can only bear axial load in one direction. Usually, in order to balance and limit the axial displacement of the shaft, a bearing that can withstand the axial load in the other direction needs to be installed at another support. Attached pictures: As can be seen from the picture, the series connection only increases the carrying capacity of the axial force, but it can only bear one direction. As you said, it can only bear the downward axial force. If they are arranged in series in the downward direction, then you need to consider two points.: 1. Is it necessary to connect two bearings in series? Is it enough for one bearing to bear the axial force? 2. Who will bear the axial force in the opposite direction after the series connection? As you said, there are deep groove ball bearings for support, but we know that the deep groove balls are mainly used to bear radial force and can only carry a small amount of axial force. If the axial force in the opposite direction is large, can the deep groove ball bearings be able to bear it? Considering that the original design intention of the air cooler manufacturer is to withstand both axial forces in different directions (two angular bearings) and radial forces (one deep groove ball bearing), there must be a reason for this, so it is recommended to call the manufacturer or consult the design manufacturer before making any changes. This post was last written by * Edited by QIU on 2009-4-13 01:30 ]

Thank you so much* QIU's wonderful answer. We have tested one unit for face-to-face to back-to-back assembly. It is currently running, and the vibration and sound are good. It remains to be seen. I am really considering changing to a series assembly. In fact, when the fan blows upward, the wind has a downward thrust on the blades. The axial force should be single. We will try it next time and communicate with you again. Thank you again. * QIU.

Do other brothers have any suggestions?