UCP218 bearing: complete specifications & equivalents
The UCP218 is a JIS B 1559 radial bearing sized 90 x 160 x 96 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 | 90 mm |
| Outer diameter D | 160 mm |
| Width B | 96 mm |
| Seal / shield | 2RS |
| Basic dynamic load rating C | 106 kN |
| Basic static load rating C0 | 71.5 kN |
| Fatigue load limit Pu | 5 kN |
| Mass | 13000 g |
| Housing height H | 101.6 mm |
| Housing overall length L | 327 mm |
| Mounting bolt center distance J | 262 mm |
| Mounting hole diameter N | 27 mm |
| Manufacturer designation | UCP218 |
| 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 | 3.543 in |
|---|---|
| Outer diameter D | 6.299 in |
| Width B | 3.78 in |
| ISO bore code | 18 |
| Radial section height (D−d)/2 | 35 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) | 18 of 25 |
| Bore above smallest UCP-series size | 78 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| UCP218 | 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 UCP218 model number is decoded
NTN ships the UCP218 as a matched assembly — UC218D1 insert swaged into the P218 cast-iron pillow block — so the fitter never has to set bearing-to-housing clearance. The code breaks down as insert family UC, housing form P (pillow block), duty series 2, bore code ending in the 90 mm shaft size; the unit is built from insert UC218D1 and housing P218. For layout work on UCP218: the 90 mm shaft centre sits 101.6 mm above the sole (H), the footprint is 327 mm long (L), bolt centres are 262 mm (J), and the foot holes suit M22 (27 mm) 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. In this bore band the X and 3 sections start to outsell the standard section: longer bearing centres and tensioned belt drives use the extra rating and stiffer base that the heavier housings provide. On machine-tool ancillary drives — chip conveyors, coolant pumps, rotary feeders — this unit is chosen because the spherical fit tolerates a frame welded without precision fixtures. The spherical outer diameter of the insert must be free to pivot in the housing bore during alignment; never pin the insert or weld the housing before the shaft has been turned through several revolutions and the alignment set. Basic ratings of the UC218D1 insert are 106 kN dynamic and 71.5 kN static; the assembled UCP218 weighs about 13.0 kg.
Typical equipment & failure modes
Common applications
- sawmill arbors and feed rolls
- cement and clinker handling
- sugar-mill and fertiliser plant drives
- elevated-temperature positions where grease life, not bearing rating, sets the interval
Known failure patterns
- 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
- lip-seal failure from grit past the slinger, followed by grease loss and abrasive wear
Selection pitfalls — read before you substitute
- The standard 2-series insert in UCP218 is the lightest section at 90 mm — do not substitute it into a position that previously ran an X or 3 unit: the 262 mm mounting may match while the load rating does not.
- As a pillow block, UCP218 needs a prepared horizontal surface at the 101.6 mm centre height: shim both feet with full-width packs so the 327 mm base seats over its full area.
- Do not confuse UCP218 with a bare UC218D1 bearing: replacing only the insert is possible, but the housing P218 must be unworn and the spherical seat cleaned and coated with anti-seize.
- When ordering covers for UCP218, note the steel and cast-iron cover executions change the unit mass and envelope but not the 262 mm mounting centres.
- Heavy drives on UCP218 should have the setscrews re-torqued after the first day; at 90 mm bore the seating forces are large and a loose inner ring frets the shaft in weeks.
Frequently asked questions
What are the dimensions of an UCP218 mounted bearing?
UCP218 takes a 90 mm shaft (insert UC218D1, 160 mm OD) and has a unit mass of about 13.0 kg. Housing figures: centre height H 101.6 mm, length L 327 mm, bolt centres J 262 mm, foot holes 27 mm for M22 bolts.
What does the UCP218 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 90 mm bore. UCP218 is built from housing P218 plus insert UC218D1 (D1 = greasable).
How is UCP218 locked to the shaft, and how tight should the setscrews be?
The UC218D1 insert uses two collar setscrews on the 90 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 UCP218 instead of a flanged unit?
Choose the UCP218 pillow block when the shaft runs parallel to a horizontal base plate, rail or plinth — the upright housing holds the shaft centre 101.6 mm above the 327 mm bolt-down base. Choose a UCFL flange when the shaft meets a vertical frame face and the housing bolts flat against it.
How often should I relubricate an UCP218 unit?
There is no single interval for UCP218: the UC218D1 insert is regreased through the D1 fitting while the shaft turns, using an NLGI 2 lithium or lithium-complex grease. Quarterly is typical for normal ambient conveyor duty; shorten to weekly or monthly where temperatures exceed about 70 °C, water is present, or dust is heavy.
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.