UCFL315 bearing: complete specifications & equivalents
The UCFL315 is a JIS B 1559 radial bearing sized 75 x 160 x 82 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 | 75 mm |
| Outer diameter D | 160 mm |
| Width B | 82 mm |
| Seal / shield | 2RS |
| Basic dynamic load rating C | 126 kN |
| Basic static load rating C0 | 77 kN |
| Fatigue load limit Pu | 5.55 kN |
| Mass | 9800 g |
| Housing height H | 320 mm |
| Housing overall length L | 195 mm |
| Mounting bolt center distance J | 260 mm |
| Mounting hole diameter N | 35 mm |
| Manufacturer designation | UCFL315 |
| 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 | 2.953 in |
|---|---|
| Outer diameter D | 6.299 in |
| Width B | 3.228 in |
| ISO bore code | 15 |
| Radial section height (D−d)/2 | 42.5 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) | 15 of 25 |
| Bore above smallest UCFL-series size | 63 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| UCFL315 | 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 UCFL315 model number is decoded
UCFL315 is an NTN two-bolt rhombus flanged unit — a setscrew-locking UC315D1 ball bearing insert pre-assembled in a FL315 cast-iron flange housing. Reading the designation: UC marks the wide-inner-ring, setscrew-locking insert; FL marks the two-bolt rhombus flange housing; the 3 code identifies the duty series and the final two digits encode the 75 mm bore. Key mounting figures: flange height H = 320 mm, overall length L = 195 mm across the diamond, bolt centres J = 260 mm, and each ear takes a 35 mm (M30) fastener for the 75 mm shaft. The 3-series section is the heavy-duty end of the range: a UC3 high-capacity insert in the longest, strongest housing, specified for shock loads and long conveyor centres. 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. At 55–90 mm bore the units carry serious conveyor, fan and crusher-feed drives; housing stiffness, foundation condition and bolt torque matter as much as the insert rating. On industrial centrifugal fans this size is standard at both shaft ends; fan loads are light but belt tension is not, and the cast housing dissipates the heat conducted out of the insert. Shim under the feet, never file the sole: full-area shim packs on both sides keep the bolt clamp load spread across the base, while a single thin shim pivots the housing and preloads the bearing. Basic ratings of the UC315D1 insert are 126 kN dynamic and 77 kN static; the assembled UCFL315 weighs about 9.8 kg.
Typical equipment & failure modes
Common applications
- heavy bulk-handling conveyors
- process fans and induced-draft drives
- quarry feeder and transfer drives
- long line-shafting where several units must share a straight reference
Known failure patterns
- spherical-seat fretting that welds insert to housing and destroys the self-aligning action
- water-emulsified grease after washdown with the fitting facing upward
- setscrew loosening and inner-ring fretting on a shaft that was never re-torqued after run-in
Selection pitfalls — read before you substitute
- UCFL315 is located on the shaft by setscrews only; for shock reversing drives consider an adapter-lock insert family instead, since setscrew points indent the 75 mm journal over time.
- At 75 mm bore the 195 mm base of UCFL315 is a structural member: grout or machine the foundation, because a bedded-on-edges housing concentrates the full belt pull on two cast feet.
- The 3-series insert makes UCFL315 the highest-rated unit at 75 mm; its advantage disappears on a soft foundation, so spend the saved margin on base stiffness rather than skipping shims.
- As a rhombus flange, UCFL315 pulls against the frame through only two M30 bolts on 260 mm centres; the mounting plate must be stiff enough not to bend between them under belt load.
Frequently asked questions
How is UCFL315 locked to the shaft, and how tight should the setscrews be?
The UC315D1 insert uses two collar setscrews on the 75 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 UCFL315 instead of a pillow block?
Choose the UCFL315 two-bolt flange when the 75 mm shaft meets a vertical frame or side plate: the diamond housing bolts flush with two M30 bolts on 260 mm centres. A UCP pillow block is used when the shaft runs above a horizontal mounting surface.
What are the dimensions of an UCFL315 mounted bearing?
UCFL315 takes a 75 mm shaft (insert UC315D1, 160 mm OD) and has a unit mass of about 9.8 kg. Flange figures: height H 320 mm, length L 195 mm, bolt centres J 260 mm, holes 35 mm for M30 bolts.
What does the UCFL315 designation mean?
UC identifies the wide-inner-ring, setscrew-locking ball bearing insert; FL the two-bolt rhombus flange housing; 3 is the duty series; the last digits encode the 75 mm bore. UCFL315 is built from housing FL315 plus insert UC315D1 (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.