What type of bearings should be used at both ends of the screw in small mechanical piston-type metering pumps?

The original bearings here are deep groove ball bearings, and the manufacturer says this type offers good performance

This post was last edited by CHANGBAISHI on 2020-3-21 07:15. It is best to use bearings of the original model; the deep-groove balls ensure proper axial positioning, and slight wear from the use of cone rods can allow for axial displacement. “The manufacturer says this type offers good performance; if a change to another type is needed, the manufacturer must provide relevant warranty documentation.

The axial positioning of deep groove ball bearings is extremely poor; you can experience this by taking a deep groove ball bearing and pushing on its inner ring with force. The advantages of deep groove balls are their simplicity in manufacturing and low cost; they are available with sealing covers, allow for a relatively large deviation angle of around 8 degrees, and are quite useful. In general design work, deep groove balls are preferred whenever possible. Tapered roller bearings have high load-carrying capacity, and this is the greatest advantage of rollers over balls. Its axial positioning is very good, but two of them are needed to achieve axial positioning. Another advantage of tapered roller bearings is that the bearing clearance can be adjusted relatively easily. As for which specific bearing to choose, it depends on the structural layout, stress analysis, and installation requirements – there is no fixed rule, just like in martial arts.

Reinstall the original model first and then observe. Other departments have pumps from the same batch; angular contact ball bearings are used at both ends of the worm

The side under stress is conical, while the other side uses deep groove ball bearings