Tilting Pad Thrust Bearing (Michell-Kingsbury) Calculator
Determine hydrodynamic oil film thickness (hmin), maximum unit pressure, and pivot load capacity for axial tilting pad thrust bearings.
Thrust Collar & Pad Geometry
Thrust Film & Load Ratings
Frequently Asked Questions
How does a tilting-pad thrust bearing generate lift without an external pump?
As the rotating thrust collar drags viscous oil over each pivot-mounted pad, the pad tilts automatically by fractions of a degree. This creates a converging hydrodynamic wedge that generates immense fluid pressure supporting the shaft.
Why is pivot offset critical in tilting pad design?
Centrally pivoted pads (50% offset) rely on thermal crowning and density variation to generate lift, whereas directed offset pivots (55%–60% from leading edge) create a much stronger hydrodynamic pressure wedge with higher load capacity.
What is the maximum allowable unit loading for turbomachinery thrust bearings?
API standards recommend keeping continuous steady-state loading below 2.8 to 3.5 MPa (400 to 500 psi) to ensure an adequate minimum oil film thickness (>20–25 μm) and prevent fatigue cracking of the Babbitt lining.