51134 bearing: complete specifications & equivalents
The 51134 is a ISO 104 radial bearing sized 170 x 215 x 34 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 170 mm |
| Outer diameter D | 215 mm |
| Width B | 34 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Basic dynamic load rating C | 134 kN |
| Basic static load rating C0 | 510 kN |
| Fatigue load limit Pu | 16.7 kN |
| Limiting speed (mechanical) | 1100 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2770 g |
| Manufacturer designation | NTN 51134 |
| 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 | 6.693 in |
|---|---|
| Outer diameter D | 8.465 in |
| Width B | 1.339 in |
| ISO bore code | 34 |
| Radial section height (D−d)/2 | 22.5 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) | 27 of 46 |
| Bore above smallest 51100-series size | 160 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the 51134 model number is decoded
NTN 51134 belongs to the light-section 51100 thrust family of single-direction thrust ball bearings: 170 / 215 / 34 mm (shaft bore / OD / height). The designation is 511 is the dimension series (light-section 51100 thrust family) plus 34 encodes the 170 mm bore (bore code x 5). The ball-and-cage set is separable from both washers, which is why the mounting order (shaft washer first, then cage, then housing washer) matters. Selection starts from the load direction: if thrust ever reverses, plan a second thrust bearing (or a double-direction execution) rather than relying on the unloaded raceway. After assembly, rotate under light load and check torque and temperature rise — a thrust ball bearing mounted with the washers swapped runs, but fails fast.
Typical equipment & failure modes
Common applications
- large marine winch and windlass shafts
- heavy press and mill screwdown thrust seats
- crane slew-ring auxiliary thrust positions
- large mixer and reactor vertical shafts
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
- lubricant starvation scoring on the raceway track when grease is thrown outward by centrifugal effect and never replaced
- contamination pitting from particles settling on the horizontal housing washer — the classic failure of vertical-shaft grease-lubricated seats
Selection pitfalls — read before you substitute
- For a 170 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 170 mm bore it gives up load to gain OD, height and limiting-speed headroom.
- Do not reuse a thrust bearing to "absorb" shaft thermal growth — the bearing clamps axially, so growth must be handled on the radial-bearing side of the arrangement.
- Swapping the shaft and housing washers is an easy assembly error on the 170 mm size — the bores differ only slightly, but the wrong pairing walks off-centre under load.
- Radial load is the silent killer here: a belt pull or gear force on the same shaft must land on a radial bearing, because 51134 has no radial capacity at all.
- The Ca 134/C0a 510 kN ratings and 16.7 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 51134; 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 51134?
51134 is a single-direction thrust ball bearing to ISO 104: 170 mm shaft-washer bore, 215 mm outside diameter, 34 mm stack height (6.693 x 8.465 x 1.339 in). From NTN Ball and Roller Bearings CAT.No.2203E: axial Ca 134 kN, C0a 510 kN and a 16.7 kN fatigue load limit Pu; the grease limiting speed is 1,100 r/min and the oil rating 1,600 r/min; mass about 2770 g.
How is the 51134 designation structured?
511 is the dimension series (light-section 51100 thrust family); 34 encodes the 170 mm bore (bore code x 5). The 215 mm OD and 34 mm height follow the ISO 104 boundary plan for that series.
Can 51134 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 51134?
At the 1,100 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 51134?
The 170/215/34 mm envelope is ISO 104 interchangeable, but washer bore codes, raceway osculation and ratings are maker-specific. Re-verify Ca 134 kN / C0a 510 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.