Engineering tool · opposed bearing pair
δ = Fa / (K1 + K2)Preload & Stiffness Calculator
Evaluate a linearized opposed-bearing pair for axial displacement, reaction forces and preload loss under external axial load.
Linearized pair model
Check preload retention
Enter tangent axial stiffness values at the preload operating point. The model is valid only while both bearings remain loaded.
RESULT / 02
Loaded pair response
Linearized about the preload point
Axial displacement δ——
Loaded bearing force Q1—preload plus increment
Opposing bearing force Q2—remaining contact force
Pair stiffness—K1 + K2
Unload threshold—external axial force
δ = Fa / (K1 + K2)
Calculation method
Local linear approximation
The external axial load increases the reaction on one bearing and reduces the reaction on the opposing bearing.
01 / DISPLACEMENTδ = Fa / (K1 + K2)
Stiffness values must be tangent values at the current preload and contact geometry.
02 / REACTIONSQ1 = F0 + K1δ · Q2 = F0 − K2δ
The pair remains preloaded only while Q2 stays above zero.
03 / LIMITBearing stiffness is nonlinear
Use manufacturer load-deflection data or a detailed bearing-system model for final design.