Severe rounded gauge and/or hole reaming

[sunrise111]

Severe rounded gauge and/or hole reaming - ???

While there is a net outward thrust, drilling is a dynamic operation and the cone/bearing will instantaneously also see inward thrust. The ball races are designed to absorb this inward thrust and retain the cone on the head section. Severe rounded gauge and/or hole reaming put high inward thrust forces on the ball bearing element, resulting in less ball race life.
Заранее спасибо.