Linear elasticity: The calculator is based on elastic deformation (Lame's
equation), i.e. the stresses should be smaller than the elastic
limit of the element materials. Hollow shaft: This
calculator is applicable for hollow shafts (D_{i}>0).
Self locking: The cone type shafthub connection is
self locking (F_{f}=F_{p}) when
μ=tan(α/2)=(d_{1}d_{2})/(2L)=C/2
where α is the cone angle and C=(d_{1}d_{2})/L. In
shafthub connections which need to be self locking the cone is
in the range C=0.1..0.2.
Surface roughness: The interference should be
corrected for the effect of surface roughness. The flattening of
roughness peaks by mounting under high pressure is generally
estimated at 10% of the Rzvalue where Rz=6Ra (ISO 63362). The
correction at the diametrical interference thus becomes 0.1·2·(Rz1+Rz2).
If the surface roughness of the shaft Ra1=0.5μm and that of the
bore Ra2=1μm then dδ=0.1·2·6·(0.5+1)=1.8μm and δeff=δmdδ where
δeff=effective value of diametrical interference, δm=measured
value of diametrical interference and dδ=correction for surface
roughness.
Coefficient of friction: Approximate value for the coefficient of friction
μ are: for steel  steel contacts dry
between 0.1 and 0.15, lubricated between 0.05 and 0.1, for steel
 yellow metal contacts dry between 0.05 and 0.1.
Cone type Clutches: In cone clutches which are
designed not to jam the cone is always above C>0.2. The maximum
interference pressure in cone clutches depends on the materials
used and the operating conditions (frictional heating: Limiting
PV value).
