UCP307 bearing: complete specifications & equivalents
The UCP307 is a JIS B 1559 radial bearing sized 35 x 80 x 48 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 | 35 mm |
| Outer diameter D | 80 mm |
| Width B | 48 mm |
| Seal / shield | 2RS |
| Basic dynamic load rating C | 37 kN |
| Basic static load rating C0 | 19.1 kN |
| Fatigue load limit Pu | 1.47 kN |
| Mass | 2500 g |
| Housing height H | 56 mm |
| Housing overall length L | 210 mm |
| Mounting bolt center distance J | 160 mm |
| Mounting hole diameter N | 17 mm |
| Manufacturer designation | UCP307 |
| 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 | 1.378 in |
|---|---|
| Outer diameter D | 3.15 in |
| Width B | 1.89 in |
| ISO bore code | 07 |
| 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) | 7 of 25 |
| Bore above smallest UCP-series size | 23 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| UCP307 | 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 UCP307 model number is decoded
In NTN's mounted-ball-bearing range, UCP307 is the classic upright pillow block for a 35 mm shaft: insert UC307D1, housing P307, two foundation bolts. Reading the designation: UC marks the wide-inner-ring, setscrew-locking insert; P marks the upright pillow block housing; the 3 code identifies the duty series and the final two digits encode the 35 mm bore. Key mounting figures: centre height H = 56 mm, overall base length L = 210 mm, bolt-hole spacing J = 160 mm, and each of the two feet takes a 17 mm (M14) fastener for the 35 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 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. Renewable-energy biomass handling — chipper infeed, ash drag-out conveyors — uses this unit in pairs, with the locating bearing fixed and the opposite float unit free to slide on its base slots. Relubricate through the fitting while the shaft is turning if at all possible: fresh grease pushes the old charge around the ball set and out past the seals, whereas purging a stationary bearing can rupture the seal lip. Basic ratings of the UC307D1 insert are 37 kN dynamic and 19.1 kN static; the assembled UCP307 weighs about 2.5 kg.
Typical equipment & failure modes
Common applications
- agricultural augers and bucket elevators
- small crushers and screening feeds
- textile line-shafting
- 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
- UCP307 is located on the shaft by setscrews only; for shock reversing drives consider an adapter-lock insert family instead, since setscrew points indent the 35 mm journal over time.
- With a 35 mm shaft the M14 foundation bolts of UCP307 must be re-checked after run-in — paint crush under the feet is enough to loosen both the feet and the setscrews.
- The 3-series insert makes UCP307 the highest-rated unit at 35 mm; its advantage disappears on a soft foundation, so spend the saved margin on base stiffness rather than skipping shims.
- As a pillow block, UCP307 needs a prepared horizontal surface at the 56 mm centre height: shim both feet with full-width packs so the 210 mm base seats over its full area.
Frequently asked questions
How is UCP307 locked to the shaft, and how tight should the setscrews be?
The UC307D1 insert uses two collar setscrews on the 35 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 UCP307 instead of a flanged unit?
Choose the UCP307 pillow block when the shaft runs parallel to a horizontal base plate, rail or plinth — the upright housing holds the shaft centre 56 mm above the 210 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 UCP307 mounted bearing?
UCP307 takes a 35 mm shaft (insert UC307D1, 80 mm OD) and has a unit mass of about 2.5 kg. Housing figures: centre height H 56 mm, length L 210 mm, bolt centres J 160 mm, foot holes 17 mm for M14 bolts.
What does the UCP307 designation mean?
UC identifies the wide-inner-ring, setscrew-locking ball bearing insert; P the upright pillow block housing; 3 is the duty series; the last digits encode the 35 mm bore. UCP307 is built from housing P307 plus insert UC307D1 (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.