All You Need to Know About Vertical Motor Bearings

Motors can often be classified by their orientation within an assembly, vertical and horizontal units both being common. While there are various ways in which the two motor types differ from one another, the biggest difference is in their bearing construction. Thrust bearings are common for vertical motors that feature drive pumps, yet such bearings are rarely found in horizontal motors. As vertical motors regularly necessitate specific types of bearings to avoid any lubrication or performance issues, it is very useful to have a general understanding of vertical motor bearings.

For a typical vertical motor, both thrust bearings and guide bearings are used. The thrust bearing of a vertical motor will be situated at the top of the assembly, and it will often consist of one or more angular contact bearings, a hydrodynamic plate bearing, or a spherical roller bearing. To determine the amount of thrust bearings that are required for efficient operations and an optimal motor service life, one will need to reference the force and direction of any applied axial loads. While the bearings of a vertical motor are not intended to take on momentary thrust in the opposite direction, they can perform this task to a certain degree. Generally, the thrust bearing will be able to take on no more than 30% of standard high thrust for less than 10 seconds when it is applied in the opposite direction.

While motors are classified as vertical or horizontal types, vertical motors may also be further categorized by subtype. These groups include normal thrust, in-line thrust, and high thrust motors. While normal thrust loads are generally those placed on a table in reference to the speed and horsepower of a motor, high thrust loads will be 175%, 250%, or 300% multiples of normal thrust.

For most loads, angular-contact ball bearings are the most common thrust bearing option. While one motor ball bearing is suitable for normal loads, two bearings placed in tandem can take on 175% thrust loads, and three bearings may be used for 250% thrust loads. In some instances, as much as five ball bearings may be situated in a stack to ensure loads are supported. When high loads begin to reach into the realm of 300% to 500% of normal thrust values, then a spherical roller bearing may be implemented. Oftentimes, these bearings are found in deep wells where water columns, pump shafts, impellers, and moving water all create thousands of pounds of force that needs to be handled.

For some of the most extreme loads, hydrodynamic bearings known as tilting-pad, plate, or Kingsbury bearings may be relied on. While these bearings can handle extremely high thrust loads, they also offer the benefit of having a very long service life for reliability. As an oil film is present for the means of separating moving parts, hydrodynamic bearings theoretically face no wear on their plates.

With a better understanding of bearing options for vertical motors, it can be much easier to make a purchasing decision. Here at Purchasing Sphere, we can help you save time and money while procuring every thrust bearing, spring bearing, locknut bearing, or other bearing assembly part you need. We also carry other types of hardware such as fastener actuator components and aviation supplies, ensuring that all your projects are accommodated. On our database, we host over 2 billion new, used, obsolete, and hard-to-find products, all of which are ready for purchase on our website at any time.

As you explore our current set of offerings, fill out and submit RFQ forms for any items of interest so that you may receive customized quotes for your comparisons with ease. If you have any further questions, we can also be reached by phone or email at any time, and we would be more than happy to assist you however we can! Get started today and see why countless customers across the globe continue to rely on Purchasing Sphere for all their operational needs.


July 3, 2024

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