UCP211 bearing: complete specifications & equivalents
The UCP211 is a JIS B 1559 radial bearing sized 55 x 100 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 | 55 mm |
| Outer diameter D | 100 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 | 3400 g |
| Housing height H | 63.5 mm |
| Housing overall length L | 219 mm |
| Mounting bolt center distance J | 171 mm |
| Mounting hole diameter N | 20 mm |
| Manufacturer designation | UCP211 |
| 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 | 2.165 in |
|---|---|
| Outer diameter D | 3.937 in |
| Width B | 2.189 in |
| ISO bore code | 11 |
| Radial section height (D−d)/2 | 22.5 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) | 11 of 25 |
| Bore above smallest UCP-series size | 43 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| UCP211 | 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 UCP211 model number is decoded
In NTN's mounted-ball-bearing range, UCP211 is the classic upright pillow block for a 55 mm shaft: insert UC211D1, housing P211, two foundation bolts. The UCP211 number follows NTN's mounted-unit convention: housing letter P, 2-series section, bore code for 55 mm; P211 and UC211D1 are the separate housing and insert part numbers inside. Shaft size is 55 mm; the cast base stands 63.5 mm to the shaft centre (H), is 219 mm long overall (L), and the two foundation holes on 171 mm centres (J) clear 20 mm M16 bolts. 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 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. Large-bore mounted units like this are selected on calculated bearing life plus foundation quality — the cast base is now a structural part of the drive, not just a convenient clamp. Sugar and fertiliser handling relies on this unit where corrosion and fine crystals attack everything: the sealed insert and the grease nipple let crews purge contaminated grease after each campaign. Check the shaft itself is straight to roughly 0.05 mm over the bearing centres before blaming a noisy new unit: mounted bearings accept housing misalignment but cannot offset a bent shaft. Basic ratings of the UC211D1 insert are 48 kN dynamic and 29.2 kN static; the assembled UCP211 weighs about 3.4 kg.
Typical equipment & failure modes
Common applications
- quarry feeder and transfer drives
- sawmill arbors and feed rolls
- cement and clinker handling
- wet, abrasive or chemically aggressive environments relying on the lip seals and slingers
Known failure patterns
- fretting corrosion of the shaft journal under the wide inner ring after years of micro-creep
- lip-seal failure from grit past the slinger, followed by grease loss and abrasive wear
- spherical-seat fretting that welds insert to housing and destroys the self-aligning action
Selection pitfalls — read before you substitute
- UCP211 is located on the shaft by setscrews only; for shock reversing drives consider an adapter-lock insert family instead, since setscrew points indent the 55 mm journal over time.
- UCP211 at 55 mm uses M16 bolts that need a torque wrench and a cross pattern; pulling one bolt first tips the 63.5 mm centre height and binds the insert.
- The standard 2-series insert in UCP211 is the lightest section at 55 mm — do not substitute it into a position that previously ran an X or 3 unit: the 171 mm mounting may match while the load rating does not.
- As a pillow block, UCP211 needs a prepared horizontal surface at the 63.5 mm centre height: shim both feet with full-width packs so the 219 mm base seats over its full area.
Frequently asked questions
How is UCP211 locked to the shaft, and how tight should the setscrews be?
The UC211D1 insert uses two collar setscrews on the 55 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 UCP211 instead of a flanged unit?
Choose the UCP211 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 219 mm bolt-down base. Choose a UCFL flange when the shaft meets a vertical frame face and the housing bolts flat against it.
What are the dimensions of an UCP211 mounted bearing?
UCP211 takes a 55 mm shaft (insert UC211D1, 100 mm OD) and has a unit mass of about 3.4 kg. Housing figures: centre height H 63.5 mm, length L 219 mm, bolt centres J 171 mm, foot holes 20 mm for M16 bolts.
What does the UCP211 designation mean?
UC identifies the wide-inner-ring, setscrew-locking ball bearing insert; P the upright pillow block housing; 2 is the duty series; the last digits encode the 55 mm bore. UCP211 is built from housing P211 plus insert UC211D1 (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.