= Bearing nominal axial setting
A <bearing nominal axial setting> is the chosen reference position of a shaft/support assembly within its available <bearing axial travel interval>. It determines how much travel remains in each direction before thermal or assembly changes encounter a limit. The locating support establishes the axial reference, while the <non-locating bearing> arrangement accommodates the permitted movement.<Rolling bearings by SKF>[Section B.2, printed p.70, axial location, relative displacement and tolerance accumulation]{ref}
Let physical travel be $[a,b]$, nominal setting $x_0$ and all required changes be $d\in[d_{\min},d_{\max}]$. Feasibility requires
$$
x_0\in[a-d_{\min},\ b-d_{\max}].
$$
The interval is nonempty exactly when the available span is at least the required span. This follows directly by requiring $a\le x_0+d_{\min}$ and $x_0+d_{\max}\le b$.
For an original example, physical travel $[-0.30,0.30]\,\mathrm{mm}$ and required changes $[-0.17,0.23]\,\mathrm{mm}$ permit settings from $-0.13$ to $+0.07\,\mathrm{mm}$. Setting $x_0=-0.03\,\mathrm{mm}$ gives operating endpoints $-0.20$ and $+0.20\,\mathrm{mm}$, leaving0.10mm at each limit. Setting $x_0=0$ instead leaves0.13mm on one side and0.07mm on the other.
The worst endpoint <bearing axial travel margin> is
$$
m(x_0)=\min\{x_0+d_{\min}-a,\ b-x_0-d_{\max}\}.
$$
In this symmetric-margin objective, its maximum occurs at $x_0=(a+b-d_{\min}-d_{\max})/2$, with $m_{\max}=[(b-a)-(d_{\max}-d_{\min})]/2$. The example gives0.10mm. A real setting can have additional positioning requirements; balancing these geometric margins alone does not determine every functional constraint.
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