FafnirRCJT1 1/8Two-Bolt Flange Mounted Ball Bearing Unit, 1-1/8 in Bore, Eccentric Locking Collar

Product Description

What this part is

A Fafnir RCJT1-1/8 two-bolt flanged mounted ball bearing unit sized for a 1-1/8 in shaft. The cast-iron flange housing carries a G1102KRRB wide-inner-ring insert with shroud contact seals and an eccentric self-locking collar.

Decoding the designation

RCJT is the Fafnir Industrial-series two-bolt flanged housed unit with an eccentric locking collar. The trailing 1-1/8 is the shaft size in inches. In the insert number G1102KRRB, G marks a relubricatable wide-inner-ring bearing with Mechani-Seal contact seals, 1102 encodes the 1-2/16 in – that is 1-1/8 in – bore, KRR denotes the wide inner ring with two contact seals and eccentric collar, and B adds a snap-ring groove and retaining ring on the outer ring.

Housing style and bolt pattern

Housing construction: two-bolt flange, oval flange face
Bolt hole spacing J: 116.7 mm / 4.594 in centre to centre
Bolt hole size N: 11.5 mm / 0.453 in
Flange thickness A1: 11.9 mm / 0.469 in
Total length H: 141.3 mm / 5.563 in
Total height L: 79.4 mm / 3.126 in
Housing width A: 29.9 mm / 1.177 in

What these specs mean in practice

An eccentric collar locks the insert to the shaft by cam action: the collar is turned in the direction of shaft rotation and then set with its cup-point setscrew, so the drive tends to tighten the collar rather than release it. The same envelope with a concentric collar carries the designation RCJTC, which clamps square to the shaft instead. The wide inner ring gives the collar a seat and lets the unit run on plain commercial shafting rather than a ground journal. The spherical surface between insert and housing gives static self-alignment, set up at assembly.

Published ratings and mounting data

Shaft size d: 1-1/8 in (28.575 mm)
Insert bearing number: G1102KRRB
Seal type: shroud contact seal
Dynamic load rating: 21 600 N / 4 850 lbf
Static load rating: 11 300 N / 2 530 lbf
Dimension B1: 48.4 mm / 1.906 in
Dimension S1: 30.1 mm / 1.185 in
Dimension E: 50.5 mm / 1.988 in
Dimension d1: 44.1 mm / 1.736 in
Timken SAP material ID: 100201544

Quantity and configuration

Complete flange unit: housing, insert bearing and eccentric locking collar. 1 Pc.

Fitting notes

The flange face seats against a flat rigid vertical surface, shimmed where the face is uneven, with the two bolts drawn up evenly. The collar setscrew is tightened after the collar has been cammed round in the direction of shaft rotation. The insert is relubricatable through the G-series grease path.

Interchange guidance

The replacement insert for this housing is the Fafnir G1102KRRB, the same insert fitted to the RAS1-1/8 pillow block. RCJTC1-1/8 is the concentric-collar variant of the same two-bolt flange envelope and RCJ1-1/8 is the four-bolt flange unit in the same Industrial series; both are related sizes with a different locking method or bolt count.