SealMasterFB-12TCThree Bolt Flange Bracket Bearing Unit, 3/4″ Bore, Cast Iron, Self-Aligning, Contact Seals, Regreasable — Complete Unit

Product Description

What this part is

A Sealmaster FB-12TC: a complete flange-bracket mounted bearing unit with a 3/4 in bore. Cast iron three-bolt bracket, self-aligning ball bearing insert already fitted, contact seals, and a grease fitting.

Like any flange unit, it bolts to a surface that the shaft passes through — a plate, a machine side frame, a bulkhead — as opposed to a pillow block, which sits on a base alongside the shaft. Whether the mounting face is perpendicular or parallel to the shaft is usually the whole decision.

Decoding the order code

FB: Sealmaster three-bolt flange bracket housing, standard duty, one-piece solid cast iron. Distinct from the SFT two-bolt flange and the SF four-bolt square flange, and bolt count determines the hole pattern to be drilled or matched.

12: bore in sixteenths of an inch. 12/16 in = 3/4 in. The same convention runs through the range, so ER-12 and FB-12 share a bore.

TC: the closure and locking specification. Sealmaster’s own product descriptions specify the base FB-12 with felt seals and a setscrew locking collar, while the TC-suffixed units in the range (for example SFT-12TC) are specified with contact seals and a Skwezloc collar. On that basis TC denotes the contact-seal, Skwezloc-collar build.

Self-alignment is the reason to choose a Sealmaster unit:
The insert in a Sealmaster flange bracket is not rigidly fixed in the housing. It has a spherical outer surface seated in a matching spherical bore, so the whole bearing can swivel a few degrees relative to the bracket. Sealmaster publishes roughly ±2° of misalignment capability on the FB family.

Two degrees does not sound like much until you put a number on it. Over a 30 in shaft span, 2° is more than an inch of offset between the two bearing centres. That is the difference between a unit that bolts to a fabricated frame with hand-drilled holes, and one that needs a machined and line-bored housing. It is also what saves the installation when a frame flexes under load or a mounting face is not quite true.

Self-alignment takes up static angular error at assembly. It does not remove the load caused by misalignment and it does not compensate for a bent shaft: a shaft that is misaligned and rotating still generates a cyclic load the bearing carries.

Contact seals and regreasability

Contact seals rub on the inner ring, which means they genuinely exclude dust, water and washdown spray rather than merely deflecting it — a step up from the felt seals on the base FB-12. Felt is adequate in a clean dry plant.

Paired with the grease fitting, that is the arrangement that works in dirty duty: a positive seal to keep contamination out, plus the ability to purge fresh grease through and push out whatever gets past. A sealed-for-life unit in the same position has no way to eject contamination once it is inside.

Published data

Bore: 3/4 in (0.750 in).

Housing style: three-bolt flange bracket, one-piece solid.

Housing material: cast iron.

Duty rating: standard duty.

Insert type: self-aligning ball bearing.

Misalignment capability: approximately ±2°, published for the FB family.

Seals: contact seals.

Lubrication: regreasable, grease fitting provided.

Bolt holes: 3.

Bolt centre to centre: 1.6875 in.

Quantity and configuration

Sold as one complete unit: cast iron three-bolt bracket with the self-aligning ball bearing insert already fitted. The insert inside an FB-12TC is an ER-12TC, and inserts are catalogued as separately replaceable items — where a bearing fails and the bracket is sound, the insert alone is the service part, which is the main practical advantage of the Sealmaster architecture. Central Surplus stocks the ER-12TC as its own line.

Interchange guidance

Search forms include FB-12TC, FB12TC, FB-12-TC, FB 12 TC, FB-12, FB12. Related Sealmaster units at the same 3/4 in bore: FB-12 (felt seals, setscrew collar), FB-12T, SFT-12TC (two-bolt flange, contact seals, Skwezloc collar), SF-12TC (four-bolt square flange), NP-12TC and SP-12TC (pillow blocks), and the ER-12TC and ER-12 inserts. Same-bore three-bolt flange brackets are catalogued by Dodge (F3B and FB families), Browning, Link-Belt and Timken; bore, bolt count, bolt-hole spacing, seal type and collar type govern whether any of them is a drop-in, because bolt patterns are not standardised across brands. Sealmaster and Link-Belt both now sit under Regal Rexnord, so units originally specified under either name are supported today.