UCFL205 bearing: complete specifications & equivalents
The UCFL205 is a JIS B 1559 radial bearing sized 25 x 52 x 34.1 mm (bore x OD x width) with 2RS sealing. Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 25 mm |
| Outer diameter D | 52 mm |
| Width B | 34.1 mm |
| Seal / shield | 2RS |
| Basic dynamic load rating C | 15.5 kN |
| Basic static load rating C0 | 7.85 kN |
| Fatigue load limit Pu | 0.55 kN |
| Mass | 600 g |
| Housing height H | 130 mm |
| Housing overall length L | 68 mm |
| Mounting bolt center distance J | 99 mm |
| Mounting hole diameter N | 16 mm |
| Manufacturer designation | UCFL205 |
| Standard | JIS B 1559 |
| Catalog version | CAT. No. 2203-3/E 2024 |
| Last verified | 2026-09-25 |
Source: catalog reference (CAT. No. 2203-3/E 2024) · extracted 2026-09-25
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (CAT. No. 2203-3/E 2024); NTN® is a trademark of NTN Corporation, used here for identification only — mpnbase is not an authorized NTN distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at ntnglobal.com.
Dimensions in inches & UCFL-series range
| Bore d | 0.984 in |
|---|---|
| Outer diameter D | 2.047 in |
| Width B | 1.343 in |
| ISO bore code | 05 |
| Radial section height (D−d)/2 | 13.5 mm |
| Smallest bore in UCFL-series | 12 mm |
| Largest outer diameter in UCFL-series | 300 mm |
| Width range across UCFL-series | 31–145 mm |
| Bore position in UCFL-series (smallest first) | 5 of 25 |
| Bore above smallest UCFL-series size | 13 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| UCFL205 | ISO 15 | verify Commonly quoted cross reference; confirm against the target catalog before ordering. | ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range. Brand-specific OEM equivalents pending multi-source data. |
Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.
How the UCFL205 model number is decoded
UCFL205 belongs to NTN's UCFL line of two-bolt rhombus flanged units, built on a JIS B 1558 UC205D1 insert in a JIS B 1559 FL205 housing. On the nameplate, UCFL205 decodes as a UC wide-inner-ring insert in a FL diamond flange, 2-series duty, 25 mm bore; the UC205D1 designation shows the D1 greasable execution. Boundary data for the 25 mm bore: 130 mm high flange, 68 mm long over the rhombus, 99 mm hole centres for M14 fasteners through 16 mm holes; insert OD is 52 mm. The 2-series section is the standard-duty choice — the slimmest, lightest housing at this bore, selected when shaft speed and load are moderate and space is normal. The diamond flange carries the shaft square to a vertical face — a welded frame, side plate or gearbox wall — so no base plinth and no shim pack under the bearing are required. The 25–50 mm bore band is the workhorse of industry — belt conveyors, fans, agricultural drives and small process machines — which is why this range has the fullest choice of series and cover options. Mining feeder and screen-feeder drives use the heaviest available section at this bore: the base must resist belt-pull reaction, and crews grout the sole rather than bolting to bare plate. For the flanged form, the mounting face must be flat within the housing’s own tolerance; a weld bead or plate step under one ear twists the housing and binds the insert even though the shaft looks centred. Basic ratings of the UC205D1 insert are 15.5 kN dynamic and 7.85 kN static; the assembled UCFL205 weighs about 0.6 kg.
Typical equipment & failure modes
Common applications
- textile line-shafting
- machine-tool chip conveyors
- belt conveyor head, tail and bend pulleys
- fan drives where belt tension, not transmitted torque, sets the radial load
Known failure patterns
- housing-foot cracking beside an over-torqued or under-supported foundation bolt
- grease starvation on long intervals in hot positions, with the ball set running on dried thickener
- fretting corrosion of the shaft journal under the wide inner ring after years of micro-creep
Selection pitfalls — read before you substitute
- UCFL205 is located on the shaft by setscrews only; for shock reversing drives consider an adapter-lock insert family instead, since setscrew points indent the 25 mm journal over time.
- In this bore band the temptation is to choose UCFL205 on shaft size alone; belt pull often dominates the radial load, so rate the unit against the overhung pulley force, not just transmitted power.
- The standard 2-series insert in UCFL205 is the lightest section at 25 mm — do not substitute it into a position that previously ran an X or 3 unit: the 99 mm mounting may match while the load rating does not.
- As a rhombus flange, UCFL205 pulls against the frame through only two M14 bolts on 99 mm centres; the mounting plate must be stiff enough not to bend between them under belt load.
Frequently asked questions
How is UCFL205 locked to the shaft, and how tight should the setscrews be?
The UC205D1 insert uses two collar setscrews on the 25 mm shaft. Tighten them to NTN's torque table for this bore size in sequence — half torque on the first, full on the second, then back to the first — and re-torque after the first 24–48 running hours once the collar has seated.
When should I choose a rhombus flange unit like UCFL205 instead of a pillow block?
Choose the UCFL205 two-bolt flange when the 25 mm shaft meets a vertical frame or side plate: the diamond housing bolts flush with two M14 bolts on 99 mm centres. A UCP pillow block is used when the shaft runs above a horizontal mounting surface.
What are the dimensions of an UCFL205 mounted bearing?
UCFL205 takes a 25 mm shaft (insert UC205D1, 52 mm OD) and has a unit mass of about 0.6 kg. Flange figures: height H 130 mm, length L 68 mm, bolt centres J 99 mm, holes 16 mm for M14 bolts.
What does the UCFL205 designation mean?
UC identifies the wide-inner-ring, setscrew-locking ball bearing insert; FL the two-bolt rhombus flange housing; 2 is the duty series; the last digits encode the 25 mm bore. UCFL205 is built from housing FL205 plus insert UC205D1 (D1 = greasable).
Reviewed & verified by the MPN Base engineering desk against source catalog CAT. No. 2203-3/E 2024 on 2026-09-25. Read our editorial & correction policy.