Mounted Bearings

Setscrew-locked units use one or two setscrews pressed directly against the shaft, which is simple and adequate for light-to-moderate, low-vibration loads but can loosen over time. Eccentric locking collar units use a collar that wedges against the inner race when rotated against shaft rotation, providing a more secure, self-tightening grip that resists loosening under vibration and shock — the standard choice for agricultural and heavy-duty conveyor applications.

Most mounted bearing inserts use a spherical outer race that self-aligns within the housing, typically accommodating a few degrees of angular misalignment (commonly up to about 3-4 degrees depending on the manufacturer) without inducing extra load on the bearing — but this doesn't substitute for reasonably accurate initial shaft alignment during installation.

Take-up units mount in a slotted frame or track that allows the bearing (and the shaft it supports) to slide, which is needed wherever belt or chain tension must be adjustable after installation — most commonly on conveyor tail shafts. A standard pillow block bolts in a fixed position and offers no adjustment travel.

Cast iron housings will corrode under repeated washdown or chemical exposure, so food, beverage and pharmaceutical applications typically specify stainless steel or solid thermoplastic housings with FDA-compliant seals instead — the bearing insert itself is often also upgraded to stainless or coated components in these environments.

Mounted bearing bores are manufactured to standard fractional-inch or metric sizes with a defined fit tolerance range — a shaft slightly outside standard sizing may need to be machined down (or up, with a bushing/sleeve) to the nearest standard bore rather than sourcing a custom bearing, which is far more costly and slower to obtain.