This term means that the drilling or boring is done on a jig that insures every component is in a straight line.
You should not install more than two precision bearings on a shaft that has not been line bored. This error is frequently made when a mixer or agitator is converted from conventional packing to a mechanical seal.
In an attempt to stabilize the shaft movement a third precision bearing is often installed near the mechanical seal. With three bearings on the shaft and the unit not line bored, one of the bearings will be overloaded.
- On February 16, 2018