Flange Bearing Units

4-bolt square · 3-bolt bracket · 2-bolt oval · Adjustable flange · Setscrew, eccentric collar, concentric collar & adapter sleeve · Shaft bore 12–140 mm

4
Flange Formats
4
Locking Styles
12 mm
Min. Bore
140 mm
Max. Bore
Bearings › Flange Bearing Units
Select by: ■ 4-Bolt Square △ 3-Bolt Bracket ◯ 2-Bolt Oval ↻ Adjustable ⚙ Heavy Duty 🔄 Eccentric / Concentric

4-Bolt Square Flange Units

Square four-bolt flange plate with bolt holes at each corner. Mounts perpendicular to the shaft axis on any flat face — vertical wall, inclined panel, or horizontal plate. Four-corner bolt pattern distributes reaction load equally and resists housing tilt under belt pull or eccentric radial loads better than two-bolt designs. UC insert bearings are interchangeable with the equivalent pillow block (UCP200/UCP300) and two-bolt oval flange (UCFL200/UCFL300) for the same bore size.

UCF200 series 4-bolt square flange bearing unit standard duty setscrew locking
Setscrew

UCF200 Series

Standard Duty — Setscrew

d 12–90 mm · 19 sizes

Same UC insert as UCP200 · Metric & inch bore · UCWF A3-slot variant · End caps available

NAF200 series 4-bolt square flange bearing unit eccentric locking collar
Eccentric Collar

NAF200 Series

Standard Duty — Eccentric Collar

d 12–75 mm · 16 sizes

Self-tightening under unidirectional rotation · NAF201S–203S slim variant · Unidirectional drives only

UEF200 series 4-bolt square flange bearing unit concentric locking collar high speed bidirectional
Concentric Collar

UEF200 Series

Standard Duty — Concentric Collar

d 20–60 mm · 9 sizes

360° bidirectional · No imbalance mass · High-speed and reversing drives

UKF200+H series 4-bolt square flange bearing unit tapered bore adapter sleeve locking
Adapter Sleeve

UKF200+H Series

Standard Duty — Adapter Sleeve

d 20–80 mm · 13 sizes

No shaft surface damage · HS/HA/HE sleeve variants · Rough-turned shafts

UCFX00 series 4-bolt square flange bearing unit medium duty heavier housing setscrew
Setscrew — Medium Duty

UCFX00 Series

Medium Duty — Setscrew

d 25–85 mm · 13 sizes

Heavier housing cross-section · Higher-rated UCX insert · Elevated belt-tension applications

UCF300 series heavy duty 4-bolt square flange bearing unit setscrew locking 25 to 140mm
Setscrew — Heavy Duty

UCF300 Series

Heavy Duty — Setscrew

d 25–140 mm · 21 sizes

Maximum 4-bolt square flange load capacity · UC300 insert · Metric bore only · Up to 90 kg

UCFS300 series heavy duty 4-bolt piloted flange bearing unit precision pilot back of housing
Piloted — Heavy Duty

UCFS300 Series

Heavy Duty — Piloted Housing

d 25–140 mm · 20 sizes

Precision pilot register on back face · Concentric housing location in frame bore · Repeatable reinstallation

NAFS200 series 4-bolt square flange bearing unit eccentric collar extended housing height
Eccentric — Extended Housing

NAFS200 Series

Extended Housing — Eccentric Collar

d 12–80 mm · 15 sizes

Taller housing fully encloses wide inner ring · No protrusion past flange face · Clearance-sensitive positions

3-Bolt Bracket Flange Units

Three-bolt bracket housing at 45° to the shaft axis — one top-centre bolt and two lower-corner bolts. More rotation resistance than a two-bolt oval flange, less frame material than a four-bolt square flange. Suits corner locations and frames with three available fixing points. UCFB200A inch-based housing allows direct replacement of inch-standard 3-bolt bracket bearings without re-drilling.

UCFB200 UCFB200A series 3-bolt flange bracket bearing unit setscrew locking metric inch housing
Setscrew

UCFB200 & UCFB200A Series

Standard Duty — Metric & Inch Housing

d 12–50 mm · 7 sizes

UCFB200 metric bolt holes · UCFB200A inch-based housing for North American/British replacement

UEFB200 series 3-bolt flange bracket bearing unit concentric locking collar high speed bidirectional
Concentric Collar

UEFB200 Series

Standard Duty — Concentric Collar

d 20–50 mm · 7 sizes

360° bidirectional · No imbalance mass · High-speed and reversing bracket drives

SBFCT200 SAFCT200 series 3-bolt ductile iron flange bearing unit carriage bolt square holes
Light Duty — Ductile Iron

SBFCT200 & SAFCT200 Series

Light Duty — Carriage Bolt Holes

d 12–35 mm · 5 sizes

Ductile iron housing · Square carriage bolt holes for one-sided installation · SBFCT=setscrew / SAFCT=eccentric

2-Bolt Oval Flange Units — Standard, Medium & Heavy Duty

Oval two-bolt housing — the most widely installed flange bearing format. Two bolts on the long axis require less frame material and fewer fixings than a four-bolt square flange, while the same UC insert provides full interchangeability with UCP200 pillow block and UCF200 square flange for the same bore size. Three duty grades cover the full load range from light to heavy industrial applications.

UCFL200 series 2-bolt oval flange bearing unit standard duty setscrew locking cast iron
Setscrew

UCFL200 Series

Standard Duty — Setscrew

d 12–90 mm · 19 sizes

Same UC insert as UCP200 & UCF200 · Metric & inch bore · UCWFL slim variant · End caps available

NAFL200 series 2-bolt oval flange bearing unit eccentric locking collar unidirectional
Eccentric Collar

NAFL200 Series

Standard Duty — Eccentric Collar

d 12–75 mm · 14 sizes

Self-tightening under unidirectional rotation · NAFL201S slim variant · Insert-only upgrade from UCFL200

UEFL200 series 2-bolt oval flange bearing unit concentric locking collar high speed bidirectional
Concentric Collar

UEFL200 Series

Standard Duty — Concentric Collar

d 20–60 mm · 9 sizes

360° bidirectional · No imbalance mass · High-speed and reversing oval flange positions

UKFL200+H series 2-bolt oval flange bearing unit tapered bore adapter sleeve locking
Adapter Sleeve

UKFL200+H Series

Standard Duty — Adapter Sleeve

d 20–70 mm · 11 sizes

No shaft surface damage · HS/HA/HE sleeve variants · Repeated tensioning-safe

UCFLX00 series 2-bolt oval flange bearing unit medium duty heavier housing setscrew
Setscrew — Medium Duty

UCFLX00 Series

Medium Duty — Setscrew

d 25–50 mm · 6 sizes

Heavier housing · Higher-rated UCX insert · Metric & inch bolt sizes listed

UCFL300 series heavy duty 2-bolt oval flange bearing unit setscrew locking 25 to 140mm
Setscrew — Heavy Duty

UCFL300 Series

Heavy Duty — Setscrew

d 25–140 mm · 21 sizes

Maximum 2-bolt oval flange load · UC300 insert · Metric bore only · UCFL328=79.7 kg

2-Bolt Oval Flange Units — Specialised Variants

Purpose-engineered two-bolt oval flange housings for specific installation constraints: extended housing height to enclose wide inner rings, inch-based dimensions for North American and British machinery, compact light-duty housings with smaller footprint, and FW/FD slot-orientation variants for load-direction optimisation.

NAFLU200 series 2-bolt oval flange bearing unit eccentric collar extended housing height inner ring enclosed
Eccentric — Extended Housing

NAFLU200 Series

Extended Housing — Eccentric Collar

d 12–75 mm · 14 sizes

Taller housing fully encloses wide inner ring · No protrusion past oval flange face · Coupling-adjacent positions

UCFT200 series 2-bolt oval flange bearing unit inch housing setscrew locking North American British
Setscrew — Inch Housing

UCFT200 Series

Inch-Based Housing — Setscrew

d 12–55 mm · 9 sizes

Inch-fraction H, J, A, L dimensions · Direct fit into inch-standard frame holes without re-drilling

UEFT200 series 2-bolt oval flange bearing unit inch housing concentric collar high speed bidirectional
Concentric — Inch Housing

UEFT200 Series

Inch-Based Housing — Concentric Collar

d 20–55 mm · 8 sizes

Inch-based housing + concentric collar · 360° bidirectional · High-speed inch-standard machinery

SBLF200 SALF200 series light duty 2-bolt oval flange bearing unit compact setscrew eccentric
Light Duty

SBLF200 & SALF200 Series

Light Duty — Compact Oval

d 12–40 mm · 8 sizes

Compact housing smaller than UCFL200 · SBLF=setscrew / SALF=eccentric collar · SB/SA insert

SBFW200 SAFW200 series 2-bolt oval FW housing flange bearing unit slot same side locking
Light Duty — FW Slot

SBFW200 & SAFW200 Series

FW Housing — Slot Same Side as Locking

d 12–40 mm · 8 sizes

Bolt slot same side as setscrew/eccentric collar · Load direction optimised · SBFW=setscrew / SAFW=eccentric

SBFD200 SAFD200 series 2-bolt oval FD housing flange bearing unit slot opposite side locking
Light Duty — FD Slot

SBFD200 & SAFD200 Series

FD Housing — Slot Opposite Side from Locking

d 12–40 mm · 8 sizes

Bolt slot opposite side from setscrew/eccentric collar · SBFD=setscrew / SAFD=eccentric

SBPFTD200 SAPFTD200 series light duty ductile iron 2-bolt oval flange bearing unit carriage bolt
Light Duty — Ductile Iron

SBPFTD200 & SAPFTD200 Series

Light Duty — Carriage Bolt Holes

d 12–35 mm · 5 sizes

Ductile iron housing · Square carriage bolt holes for one-sided installation · SBPFTD=setscrew / SAPFTD=eccentric

Adjustable Flange Units

Slotted bolt holes (N1×N2 slot width × arc length) allow the entire housing to rotate about the shaft axis after the mounting bolts are partially tightened. Correct angular misalignment between shaft and panel without re-drilling, shimming, or machining the mounting surface. Essential for field-erected steel structures, welded fabrication frames, and retrofit installations where the panel face angle cannot be guaranteed.

UCFA200 series adjustable flange bearing unit slotted bolt holes angular adjustment cast iron setscrew
Adjustable — Setscrew

UCFA200 Series

Adjustable Oval Flange — Setscrew

d 12–55 mm · 11 sizes

N1×N2 slotted bolt holes · ~±30° angular housing adjustment · No re-drilling or shimming required

Series Selection Matrix

Identify the correct series by flange format, locking mechanism, and duty rating. Click the series name to view the full specification table.

Series Format Duty Locking Bore Key Differentiator
UCF2004-BoltStandardSetscrew12–90 mmSame UC insert as UCP200/UCFL200 · UCWF A3-slot variant
NAF2004-BoltStandardEccentric collar12–75 mmSelf-tightening unidirectional · NAF201S slim variant
UEF2004-BoltStandardConcentric collar20–60 mm360° bidirectional · no imbalance mass
UKF200+H4-BoltStandardAdapter sleeve20–80 mmNo shaft damage · HS/HA/HE sleeve variants
UCFX004-BoltMediumSetscrew25–85 mmHeavier housing · higher-rated UCX insert
UCF3004-BoltHeavySetscrew25–140 mmMaximum 4-bolt square load · metric bore only · up to 90 kg
UCFS3004-BoltHeavySetscrew + Pilot25–140 mmPrecision pilot on back face · repeatable concentric reinstallation
NAFS2004-BoltStandardEccentric collar12–80 mmExtended housing height fully encloses wide inner ring
UCFB200/A3-BoltStandardSetscrew12–50 mmMetric (UCFB200) or inch-based (UCFB200A) housing · 45° bracket
UEFB2003-BoltStandardConcentric collar20–50 mm360° bidirectional in 3-bolt bracket format
SBFCT/SAFCT3-BoltLightSetscrew / Eccentric12–35 mmDuctile iron · square carriage bolt holes · one-sided install
UCFL2002-BoltStandardSetscrew12–90 mmMost widely used oval flange · insert interchangeable with UCF200/UCP200
NAFL2002-BoltStandardEccentric collar12–75 mmSelf-tightening unidirectional · direct insert upgrade from UCFL200
UEFL2002-BoltStandardConcentric collar20–60 mm360° bidirectional oval flange · high-speed and reversing drives
UKFL200+H2-BoltStandardAdapter sleeve20–70 mmNo shaft damage · safe for repeated tensioning adjustments
UCFLX002-BoltMediumSetscrew25–50 mmHeavier oval housing · both metric and inch bolt sizes
UCFL3002-BoltHeavySetscrew25–140 mmMaximum 2-bolt oval load · metric bore only · UCFL328=79.7 kg
NAFLU2002-BoltStandardEccentric collar12–75 mmExtended height encloses inner ring · coupling-adjacent positions
UCFT2002-BoltStandardSetscrew12–55 mmInch-based housing · direct fit into inch-standard frame holes
UEFT2002-BoltStandardConcentric collar20–55 mmInch-based housing + concentric collar · reversing inch-frame drives
SBLF/SALF2-BoltLightSetscrew / Eccentric12–40 mmCompact housing smaller than UCFL200 equivalent bore
SBFW/SAFW2-BoltLightSetscrew / Eccentric12–40 mmFW slot: bolt slot same side as locking mechanism
SBFD/SAFD2-BoltLightSetscrew / Eccentric12–40 mmFD slot: bolt slot opposite side from locking mechanism
SBPFTD/SAPFTD2-BoltLightSetscrew / Eccentric12–35 mmDuctile iron · carriage bolt square holes · one-sided install
UCFA200AdjustableStandardSetscrew12–55 mmSlotted N1×N2 bolt holes · ~±30° angular adjustment · no re-drilling

Frequently Asked Questions

▶ What is the difference between 4-bolt square, 3-bolt bracket, and 2-bolt oval flange housings?

4-bolt square (UCF200/UCF300): four corner bolts on a square plate — highest housing rotation resistance, suits vertical frame faces. 3-bolt bracket (UCFB200): one top-centre and two lower-corner bolts at 45° — more rotation resistance than 2-bolt, suits corner locations where only three fixing points are available. 2-bolt oval (UCFL200/UCFL300): two bolts on the long axis of an oval plate — lowest material and installation cost, adequate for most light to medium duty applications. Choose based on available bolt positions and required housing rotation resistance.

▶ Are flange unit insert bearings interchangeable with pillow block inserts?

Yes. The UC series wide inner ring insert is identical for equivalent bore sizes across all standard-duty UC-family housings: UCP200 (pillow block), UCF200 (4-bolt square), UCFL200 (2-bolt oval), and UCT200 (take-up unit). Stocking one UC insert type covers all four housing formats for the same bore on the same machine, reducing spare parts inventory and simplifying in-service housing format changes.

▶ When should I choose UCFS300 (piloted) over UCF300 (standard heavy duty)?

Choose UCFS300 when the bearing position requires repeatable reinstallation without re-centring after each bearing replacement, or when the machine frame specifies a piloted flange for assembly-line positional repeatability. The precision pilot on the back face of the UCFS300 housing locates the housing concentrically in a matching frame bore independently of the bolt-tightening sequence, to an H7-fit tolerance. For standard installations where reinstallation precision is not a design requirement, UCF300 is sufficient.

▶ What do the NAFS200 and NAFLU200 extended housing variants solve?

Both use a taller housing that fully encloses the NA series wide inner ring insert within the housing profile, preventing the inner ring from protruding beyond the flange face. NAFS200 is for 4-bolt square flange positions; NAFLU200 is for 2-bolt oval flange positions. Inner ring protrusion becomes a concern at larger bore sizes where the standard NAF200/NAFL200 housing height is insufficient to contain the wide NA insert — it creates interference with adjacent couplings, guards, and covers. The extended housing eliminates this without changing any mounting bolt positions.

▶ When should I use the inch-based UCFT200/UEFT200 instead of the metric UCFL200/UEFL200?

UCFT200 and UEFT200 use housing dimensions derived from inch fractions (H, J, A2, A1, A, L in inch-fraction equivalents). When an existing machine frame has bolt holes drilled to inch-standard positions, fitting a metric UCFL200 would require slot-drilling or re-drilling to close a gap of typically 0.3–1.5 mm between metric and inch-fraction hole positions. UCFT200/UEFT200 drop into the existing inch-standard holes without modification. For new machines designed in metric, UCFL200/UEFL200 are the standard choice.

▶ What is the UCFA200 angular adjustment range and when is it needed?

The UCFA200 slotted bolt holes provide approximately ±30° of housing rotation about the shaft axis (exact range depends on bore size — check N2 slot arc length in the specification table). This adjustment corrects angular misalignment between the shaft axis and the panel face without re-drilling or shimming. It is most needed on field-erected steel structures, welded fabrication frames, and retrofit positions where the mounting panel face cannot be guaranteed perpendicular to the shaft. On machined or precision-located panels, standard UCFL200 is sufficient.

Ready to Order?

Provide shaft diameter, bore type (metric or inch), flange format, locking preference, duty rating, and quantity. New-client samples available at sample pricing. Multi-model orders from USD 1,500 accepted. Engineering drawings required before order confirmation — catalogue dimensions for reference only.