51136 bearing: complete specifications & equivalents
The 51136 is a ISO 104 radial bearing sized 180 x 225 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 | 180 mm |
| Outer diameter D | 225 mm |
| Width B | 34 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Basic dynamic load rating C | 135 kN |
| Basic static load rating C0 | 525 kN |
| Fatigue load limit Pu | 16.7 kN |
| Limiting speed (mechanical) | 1100 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2920 g |
| Manufacturer designation | NTN 51136 |
| 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 | 7.087 in |
|---|---|
| Outer diameter D | 8.858 in |
| Width B | 1.339 in |
| ISO bore code | 36 |
| 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) | 28 of 46 |
| Bore above smallest 51100-series size | 170 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the 51136 model number is decoded
At 180 x 225 x 34 mm, NTN 51136 sits in the light-section 51100 thrust family of the single-direction thrust programme. Two fields make up the code — 511 is the dimension series (light-section 51100 thrust family) and 36 encodes the 180 mm bore (bore code x 5). With Ca 135 kN and C0a 525 kN, each mm of shaft bore carries about 0.75 kN of dynamic axial rating. The 180/225/34 envelope follows ISO 104, so dimensional interchange holds between makers — raceway osculation and ratings do not automatically follow. On a vertical shaft, pack grease between the washers and plan a relubrication path — centrifugal effect drives grease outward and the track runs dry without it.
Typical equipment & failure modes
Common applications
- bulk-handler stacker/reclaimer thrust pivots
- heavy rotary furnace and kiln thrust points
- vertical hydro and pump-turbine thrust supports
- large marine winch and windlass 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
- contamination pitting from particles settling on the horizontal housing washer — the classic failure of vertical-shaft grease-lubricated seats
- cage breakage after repeated shock reversal banged the ball set against the pocket bridges
Selection pitfalls — read before you substitute
- For a 180 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 180 mm bore it gives up load to gain OD, height and limiting-speed headroom.
- Never substitute a double-direction bearing drawing part-for-part: the single-direction 51136 stack height of 34 mm and washer set differ from the double-direction execution.
- The C0a of 525 kN is a static rating: sizing continuous working thrust from C0a alone overstates what the raceway survives.
- 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 135/C0a 525 kN ratings and 16.7 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 51136; 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 51136?
51136 is a single-direction thrust ball bearing to ISO 104: 180 mm shaft-washer bore, 225 mm outside diameter, 34 mm stack height (7.087 x 8.858 x 1.339 in). From NTN Ball and Roller Bearings CAT.No.2203E: axial Ca 135 kN, C0a 525 kN and a 16.7 kN fatigue load limit Pu; the grease limiting speed is 1,100 r/min and the oil rating 1,500 r/min; mass about 2920 g.
How is the 51136 designation structured?
511 is the dimension series (light-section 51100 thrust family); 36 encodes the 180 mm bore (bore code x 5). The 225 mm OD and 34 mm height follow the ISO 104 boundary plan for that series.
Can 51136 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 51136?
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 51136?
The 180/225/34 mm envelope is ISO 104 interchangeable, but washer bore codes, raceway osculation and ratings are maker-specific. Re-verify Ca 135 kN / C0a 525 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.