SKFFY-1-3/4-TMFour-Bolt Square Flange Ball Bearing Unit, 1-3/4 in Bore, Cast Iron, Self-Aligning Insert, Set Screw Locking

Product Description

What this part is

This is a FOUR-BOLT SQUARE FLANGE ball bearing unit with a 1-3/4 in bore in a cast iron housing — and two of them are supplied.

A flange unit does the opposite job to a pillow block. It bolts to a vertical face, bulkhead or machine end plate, and the shaft runs PERPENDICULAR to that surface, straight through the mounting. That is what you want where a shaft has to pass through a wall, a hopper side or a gearbox face and there is no flat base to bolt a pillow block onto. The square four-bolt pattern spreads the load over four fasteners and resists the twisting moment a cantilevered shaft applies to the mounting.

What these specs mean in practice

The insert is a self-aligning Y-bearing: its outer ring is spherically ground and seats in a matching spherical bore in the housing, so the bearing can swivel a few degrees to take up shaft-to-housing misalignment. This is the single reason these units dominate site-built machinery — you can bolt the flange to a face that is not perfectly square to the shaft and the bearing will still run true instead of being loaded on one edge. The inner ring is extended and carries set screws, so the unit clamps directly onto a plain, undersized commercial shaft with no shoulder, keyway or interference fit needed.

A grease fitting in the housing makes the unit relubricatable in service rather than sealed for life, which matters on dusty or wet duty where the grease needs refreshing rather than just retaining.

Quantity and configuration

Supplied as two complete housed assemblies in their original SKF cartons, with the SKF Y-unit ball bearing and flanged unit assembly instruction leaflet included.

Interchange guidance

Cross-reference worth knowing: the factory carton states this unit REPLACES FY 112, so if you are working from an older parts list or drawing that specifies FY 112, this is the current-for-its-era substitute. That supersession is printed on the box, not inferred.

Note the FY inch family runs several housing-and-insert combinations — TM, TF and FM among them — which differ in insert and locking detail rather than in bore or flange pattern, so check the full suffix against your drawing rather than ordering on bore size alone. Also written FY 1.3/4 TM, FY1-3/4TM, FY-1.3/4-TM and FY 1-3/4 TM.