UCPX20 bearing: complete specifications & equivalents
The UCPX20 is a JIS B 1559 radial bearing sized 100 x 215 x 117.5 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 | 100 mm |
| Outer diameter D | 215 mm |
| Width B | 117.5 mm |
| Seal / shield | 2RS |
| Basic dynamic load rating C | 147 kN |
| Basic static load rating C0 | 105 kN |
| Fatigue load limit Pu | 6.75 kN |
| Mass | 25000 g |
| Housing height H | 127 mm |
| Housing overall length L | 432 mm |
| Mounting bolt center distance J | 337 mm |
| Mounting hole diameter N | 33 mm |
| Manufacturer designation | UCPX20 |
| 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 | 3.937 in |
|---|---|
| Outer diameter D | 8.465 in |
| Width B | 4.626 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 57.5 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) | 20 of 25 |
| Bore above smallest UCP-series size | 88 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| UCPX20 | 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 UCPX20 model number is decoded
The NTN UCPX20 unit pairs a UCX20D1 sealed ball bearing insert with a one-piece PX20 cast-iron pillow block housing, delivered aligned, greased and ready to bolt down. On the nameplate, UCPX20 decodes as a UC wide-inner-ring insert in a P plummer block, X-series duty, 100 mm bore; the UCX20D1 designation shows the D1 greasable execution. Boundary data for the 100 mm bore: housing centre height 127 mm, base 432 mm, mounting centres 337 mm for M27 fasteners through 33 mm holes; the UCX20D1 insert itself is 215 mm OD. 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. Above 90 mm bore these are primary process drives — mining conveyors, bulk materials handling, heavy fans — where the 3-series insert and massive casting protect against shock and contamination. HVAC air-handling units carry fan shafts on this size, usually in warm roof-space air where the grease must be rated for continuous ambient temperature rather than load. On V-belt drives, align the pulleys before finally tightening the feet; the spherical seat lets you rotate the unit, but sliding the whole base on the foundation is what removes the belt-edge wear. Basic ratings of the UCX20D1 insert are 147 kN dynamic and 105 kN static; the assembled UCPX20 weighs about 25.0 kg.
Typical equipment & failure modes
Common applications
- primary crusher feeders
- steel-plant roller tables
- large induced-draft fans
- long line-shafting where several units must share a straight reference
Known failure patterns
- 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
- insert brinelling from hammer mounting or from belt tension applied to a stationary unit
Selection pitfalls — read before you substitute
- At replacement time, measure the 100 mm shaft journal — a worn or deeply indented journal under the setscrews will let a brand-new UCPX20 creep identically to the old one.
- UCPX20 is located on the shaft by setscrews only; for shock reversing drives consider an adapter-lock insert family instead, since setscrew points indent the 100 mm journal over time.
- At 100 mm bore, rigging and alignment dominate the UCPX20 installation: the cast unit is lifted into place on the shaft, aligned on the spherical seat, and only then foot-bolted.
- The X insert of UCPX20 is wider and rated above the 2-series part at 100 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, UCPX20 needs a prepared horizontal surface at the 127 mm centre height: shim both feet with full-width packs so the 432 mm base seats over its full area.
Frequently asked questions
How is UCPX20 locked to the shaft, and how tight should the setscrews be?
The UCX20D1 insert uses two collar setscrews on the 100 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 UCPX20 instead of a flanged unit?
Choose the UCPX20 pillow block when the shaft runs parallel to a horizontal base plate, rail or plinth — the upright housing holds the shaft centre 127 mm above the 432 mm bolt-down base. Choose a UCFL flange when the shaft meets a vertical frame face and the housing bolts flat against it.
Can I replace just the insert inside an UCPX20 unit?
Yes — UCPX20 is an assembly of the PX20 housing and UCX20D1 insert, and the insert can be ordered separately if the spherical seat and feet are undamaged. Clean the seat, coat it with anti-seize, and confirm the setscrew indentations on the 100 mm shaft are not the reason the old insert failed.
What are the dimensions of an UCPX20 mounted bearing?
UCPX20 takes a 100 mm shaft (insert UCX20D1, 215 mm OD) and has a unit mass of about 25.0 kg. Housing figures: centre height H 127 mm, length L 432 mm, bolt centres J 337 mm, foot holes 33 mm for M27 bolts.
What does the UCPX20 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 100 mm bore. UCPX20 is built from housing PX20 plus insert UCX20D1 (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.