Types of Bearing Blocks (Mounted Bearings)

Bearing blocks are the ultimate supporting player in mechanical applications. Without bearing blocks, there is no mechanical transmission system. Everything falls apart without them. More accurately, nothing gets put together without them.

Here at MDS, we appreciate bearing blocks’ quiet, sturdy, ever-reliable ways. And, of course, we want to make sure you have the right bearing block for your system.

So what are bearing blocks?

Flange BearingsBearing blocks house and support the bearing, and then anchor the entire bearing complex to the mounting surface. Bearing blocks absorb the axial and radial torque produced by the shaft. Their seals keep lubrication in and contamination out of the bearing. And they need to maintain these high levels of strength and integrity while also facilitating maintenance, repairs and replacement to the bearing, shaft or other parts of the power train.

The two most common bearing block types are pillow blocks and flange blocks. The main difference between the two is the orientation of the shaft to the mounting surface.

Pillow block bearings, which are sometimes called plumber bearings, support shafts that run parallel to the mounting surface. Whether the shaft is vertical, horizontal or diagonal relative to the ground or any part of the system other than the mounting surface is irrelevant. Remember the P’s: parallel means pillow block.

Flange blocks, then, are for shafts at a right angle to the mounting surface.

Pillow Block BearingsThe different orientations necessarily determine the shape of each bearing block. A quick look at MDS of Michigan’s selection of pillow blocks and flange blocks shows how obvious the differences are. And once you know what to look for, you can not only identify a bearing block – flange blocks are flatter and usually square, whereas pillow blocks are rounded and look like an old-fashioned clock – but you can start to envision them in action. When you see a flange block, it makes sense that a shaft would pass through it going “towards” a mounting surface. Whereas the build of a pillow block makes it clear that the block is holding the shaft above and level with the surface.

MDS also carries Type E pillow blocks and flange blocks. Learn more about what Type E means here, and don’t hesitate to send us any questions you have about bearing block types or anything else in the world of power transmission.