UCPX10 bearing: complete specifications & equivalents
The UCPX10 is a JIS B 1559 radial bearing sized 50 x 110 x 55.6 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 | 50 mm |
| Outer diameter D | 110 mm |
| Width B | 55.6 mm |
| Seal / shield | 2RS |
| Basic dynamic load rating C | 48 kN |
| Basic static load rating C0 | 29.2 kN |
| Fatigue load limit Pu | 2.29 kN |
| Mass | 4100 g |
| Housing height H | 63.5 mm |
| Housing overall length L | 241 mm |
| Mounting bolt center distance J | 171 mm |
| Mounting hole diameter N | 20 mm |
| Manufacturer designation | UCPX10 |
| 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 & UCP-series range
| Bore d | 1.969 in |
|---|---|
| Outer diameter D | 4.331 in |
| Width B | 2.189 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 30 mm |
| Smallest bore in UCP-series | 12 mm |
| Largest outer diameter in UCP-series | 300 mm |
| Width range across UCP-series | 31–145 mm |
| Bore position in UCP-series (smallest first) | 10 of 25 |
| Bore above smallest UCP-series size | 38 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| UCPX10 | 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 UCPX10 model number is decoded
UCPX10 is an NTN cast-iron pillow block — a setscrew-locking wide-inner-ring ball bearing (UCX10D1) pre-assembled in a PX10 two-bolt plummer housing. NTN's numbering ties the unit to its components: UCPX10 means the PX10 housing carrying the UCX10D1 insert, with the last two digits denoting the 50 mm bore in the X-series duty class. The foundation drawing needs four numbers: H 63.5 mm centre height, L 241 mm total length, J 171 mm between the 20 mm bolt holes, and a 50 mm shaft passing through the 110 mm OD insert. The X section is NTN’s intermediate-duty build: a wider UCX insert with a higher rating sits in a longer, sturdier housing than the 2-series unit at the same bore. The upright base carries the shaft parallel to and above the mounting surface, which is the arrangement fan, conveyor and transmission drives use whenever a plinth or rail is available. Most general industrial shafting in the 25–50 mm range ends up on exactly this class of unit: designers trade the 2, X and 3 sections against conveyor centres and belt tension rather than against absolute capacity. 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 UCX10D1 insert are 48 kN dynamic and 29.2 kN static; the assembled UCPX10 weighs about 4.1 kg.
Typical equipment & failure modes
Common applications
- belt conveyor head, tail and bend pulleys
- industrial fans and blowers
- agricultural augers and bucket elevators
- low-speed heavily loaded pulleys where the static rating governs the selection
Known failure patterns
- over-greasing that churns the charge, overheats the bearing and blows the seal lip
- cracked cast ear from mounting on an uneven face and pulling one bolt fully first
- housing-foot cracking beside an over-torqued or under-supported foundation bolt
Selection pitfalls — read before you substitute
- The X insert of UCPX10 is wider and rated above the 2-series part at 50 mm, but it is not interchangeable with a 3-series unit in a damaged application — check the housing length and bolt centres before swapping.
- As a pillow block, UCPX10 needs a prepared horizontal surface at the 63.5 mm centre height: shim both feet with full-width packs so the 241 mm base seats over its full area.
- Self-aligning is not the same as free to move: the UCX10D1 insert of UCPX10 pivots to correct static misalignment, but a continuously bending shaft still frets the spherical seat.
- With a 50 mm shaft the M16 foundation bolts of UCPX10 must be re-checked after run-in — paint crush under the feet is enough to loosen both the feet and the setscrews.
Frequently asked questions
What are the dimensions of an UCPX10 mounted bearing?
UCPX10 takes a 50 mm shaft (insert UCX10D1, 110 mm OD) and has a unit mass of about 4.1 kg. Housing figures: centre height H 63.5 mm, length L 241 mm, bolt centres J 171 mm, foot holes 20 mm for M16 bolts.
What does the UCPX10 designation mean?
UC identifies the wide-inner-ring, setscrew-locking ball bearing insert; P the upright pillow block housing; X is the duty series; the last digits encode the 50 mm bore. UCPX10 is built from housing PX10 plus insert UCX10D1 (D1 = greasable).
How is UCPX10 locked to the shaft, and how tight should the setscrews be?
The UCX10D1 insert uses two collar setscrews on the 50 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 pillow block like UCPX10 instead of a flanged unit?
Choose the UCPX10 pillow block when the shaft runs parallel to a horizontal base plate, rail or plinth — the upright housing holds the shaft centre 63.5 mm above the 241 mm bolt-down base. Choose a UCFL flange when the shaft meets a vertical frame face and the housing bolts flat against it.
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.