51152 bearing: complete specifications & equivalents
The 51152 is a ISO 104 radial bearing sized 260 x 320 x 45 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 260 mm |
| Outer diameter D | 320 mm |
| Width B | 45 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Basic dynamic load rating C | 232 kN |
| Basic static load rating C0 | 990 kN |
| Fatigue load limit Pu | 26.2 kN |
| Limiting speed (mechanical) | 750 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 7380 g |
| Manufacturer designation | NTN 51152 |
| Standard | ISO 104 |
| Catalog version | NTN Ball and Roller Bearings CAT.No.2203E |
| Last verified | 2026-10-01 |
Source: catalog reference (NTN Ball and Roller Bearings CAT.No.2203E) · extracted 2026-10-01
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN Ball and Roller Bearings CAT.No.2203E); 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 & 51100-series range
| Bore d | 10.236 in |
|---|---|
| Outer diameter D | 12.598 in |
| Width B | 1.772 in |
| ISO bore code | 52 |
| Radial section height (D−d)/2 | 30 mm |
| Smallest bore in 51100-series | 10 mm |
| Largest outer diameter in 51100-series | 640 mm |
| Width range across 51100-series | 9–85 mm |
| Bore position in 51100-series (smallest first) | 33 of 46 |
| Bore above smallest 51100-series size | 250 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the 51152 model number is decoded
From the light-section 51100 thrust family, 51152 measures 260 mm through the shaft washer, 320 mm over the outside and 45 mm in assembled height. Two fields make up the code — 511 is the dimension series (light-section 51100 thrust family) and 52 encodes the 260 mm bore (bore code x 5). With Ca 232 kN and C0a 990 kN, each mm of shaft bore carries about 0.89 kN of dynamic axial rating. If the duty is high speed with light thrust, check the minimum axial load formula first; a too-large thrust ball bearing fails by skid long before its Ca of 232 kN is ever approached. The shaft washer (bore 260 mm, tight on the shaft) and the housing washer (slightly looser bore) are not interchangeable — check the catalogue bore codes before pressing anything on.
Typical equipment & failure modes
Common applications
- heavy rotary furnace and kiln thrust points
- vertical hydro and pump-turbine thrust supports
- large marine winch and windlass shafts
- heavy press and mill screwdown thrust seats
Known failure patterns
- cage pocket wear and ball skid polish after long running below the minimum axial load, the balls sliding instead of rolling on the washers
- housing-washer rocking on an out-of-square support face, seen as uneven wear around the raceway circle and rising running torque
- early fatigue from thrust reversal hammering the unloaded raceway, because the bearing has no contact surfaces for the opposite direction
- cage breakage after repeated shock reversal banged the ball set against the pocket bridges
- cage breakage after repeated shock reversal banged the ball set against the pocket bridges
Selection pitfalls — read before you substitute
- For a 260 mm bore thrust bearing, the seating surfaces and oil supply decide service life; at this size a field-improvised housing is the usual root cause behind "premature" failures.
- The 511 light section is the speed-friendly end of the thrust-ball plan — for the same 260 mm bore it gives up load to gain OD, height and limiting-speed headroom.
- A housing washer pressed tight in its seat cannot self-centre; the resulting eccentric running shows up as cage wear long before raceway fatigue.
- Never substitute a double-direction bearing drawing part-for-part: the single-direction 51152 stack height of 45 mm and washer set differ from the double-direction execution.
- Grease in a horizontal-washer seat stays only if the housing is designed to hold it; open vertical arrangements need an oil bath or a grease-retaining cover.
- The Ca 232/C0a 990 kN ratings and 26.2 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 51152; raceway geometry legitimately differs between manufacturers, so re-verify ratings and washer identification before substituting another make.
Frequently asked questions
What are the dimensions and catalogue ratings of NTN 51152?
51152 is a single-direction thrust ball bearing to ISO 104: 260 mm shaft-washer bore, 320 mm outside diameter, 45 mm stack height (10.236 x 12.598 x 1.772 in). From NTN Ball and Roller Bearings CAT.No.2203E: axial Ca 232 kN, C0a 990 kN and a 26.2 kN fatigue load limit Pu; the grease limiting speed is 750 r/min and the oil rating 1,100 r/min; mass about 7380 g.
How is the 51152 designation structured?
511 is the dimension series (light-section 51100 thrust family); 52 encodes the 260 mm bore (bore code x 5). The 320 mm OD and 45 mm height follow the ISO 104 boundary plan for that series.
Can 51152 carry radial load or reversing thrust?
No. The raceways contact the balls at 90 deg to the shaft, so the rating is purely axial and single-direction. Radial load must be carried by a separate radial bearing, and reversing thrust needs a second thrust bearing or a double-direction execution.
Why does NTN specify a minimum axial load for 51152?
At the 750 r/min class speed, centrifugal and gyroscopic effects make an under-loaded ball set skid and smear instead of roll. The catalogue minimum-load formula gives the axial preload — from the machine weight, springs or a dead-weight — that keeps the contact rolling.
What should be checked before substituting another make for 51152?
The 260/320/45 mm envelope is ISO 104 interchangeable, but washer bore codes, raceway osculation and ratings are maker-specific. Re-verify Ca 232 kN / C0a 990 kN, the speed figures and the shaft/housing washer identification against the donor catalogue.
Reviewed & verified by the MPN Base engineering desk against source catalog NTN Ball and Roller Bearings CAT.No.2203E on 2026-10-01. Read our editorial & correction policy.