Which component is used to prevent axial motion in rotating machinery?

• A. Thrust bearings
• B. Journal bearings
• C. Radial bearings
• D. Spherical bearings

Answer: (A)

Preventing axial motion in rotating machinery is accomplished by thrust bearings. These bearings are designed to carry loads along the shaft axis, resisting end thrust and keeping the shaft from moving forward or backward under operating forces from gears, impellers, or other rotating components. Journal and radial bearings handle loads perpendicular to the shaft and don’t constrain movement along the axis, while spherical bearings can handle some angular misalignment and both radial and axial components but are not the primary device used to stop axial motion. So the component chosen to prevent axial motion is thrust bearings.