RHPSF1-1/4Self-Lube 4-Bolt Square Flange Mount Bearing Unit, 1-1/4″ Bore, Setscrew Lock, Cast Iron

Product Description

What this part is

A complete RHP Self-Lube® mounted ball bearing unit in the SF series — a one-piece cast-iron four-bolt square flange housing with a wide-inner-ring insert already fitted. Bore is 1-1/4 in. The insert seats on a spherical seating in the housing bore, which takes up initial misalignment between the shaft and the mounting face on assembly.

Housing style and bolt pattern

SF is the RHP Self-Lube® normal-duty cast-iron flange series, covering 12–75 mm and 1/2–3 in bores. The flange is square with four bolt holes, one at each corner.

Bolt hole centre-to-centre: 92 mm (3.622 in)
Flange face: 117.5 mm square (4.626 in)
Overall depth: 46.41 mm (1.827 in)
Housing material: cast iron to BS 1452

Decoding the designation

SF — normal-duty cast-iron four-bolt square flange housing
1-1/4 — nominal shaft bore in inches
No DEC or EC suffix — setscrew locking rather than an eccentric collar

What these specs mean in practice

The setscrew arrangement is two knurled cup-point screws set in the extended inner ring, tightened down onto the shaft. It is the simplest of the RHP locking options and suits general drive and conveyor duty. The eccentric-collar variants (SF-DEC, SF-EC) exist for applications where vibration is the governing condition, and the taper-sleeve arrangement for positive concentric clamping under shock load.

Internal radial clearance is C3, greater than normal. On a mounted unit the extra clearance absorbs the misalignment and shaft-fit variation that housed applications actually see, and gives room for thermal growth of the inner ring.

Published specifications

Bore: 1-1/4 in (31.75 mm)
Housing series: SF, normal duty, cast iron
Number of bolt holes: 4
Locking method: two setscrews in extended inner ring
Seal: single-lip nitrile, moulded lip bonded to a steel pressing secured in the outer ring
Internal clearance: C3
Cage: pressed steel, two-piece riveted
Relubrication: through the housing grease fitting
Seating: spherical, for initial misalignment on mounting
Standard grease temperature range: −20 to +110 °C

Quantity and configuration

1 Pc. Complete unit — cast-iron flange housing with the bearing insert fitted.

Fitting notes

The flange bolts onto a flat rigid face, shimmed where the face is uneven, and the spherical seating takes up the residual angular error as the setscrews are drawn down. Dowel pin positions are provided in the housing for locating the unit once its position is established. Relubrication runs through the grease fitting in the housing.

Interchange guidance

SF1-1/4 is the setscrew version. SF1-1/4DEC and SF1-1/4EC carry eccentric-collar locking on the same housing and are related sizes rather than substitutions. SF-HLT is the high/low-temperature build with silicone seals; PSF is the thermoplastic Silver-Lube® housing on the same bolt pattern. MSF is the heavier-duty cast-iron flange with its own bolt pattern.