51116 bearing: complete specifications & equivalents
The 51116 is a ISO 104 radial bearing sized 80 x 105 x 19 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 80 mm |
| Outer diameter D | 105 mm |
| Width B | 19 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Basic dynamic load rating C | 44.5 kN |
| Basic static load rating C0 | 141 kN |
| Fatigue load limit Pu | 6.35 kN |
| Limiting speed (mechanical) | 2200 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 422 g |
| Manufacturer designation | NTN 51116 |
| 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 | 3.15 in |
|---|---|
| Outer diameter D | 4.134 in |
| Width B | 0.748 in |
| ISO bore code | 16 |
| Radial section height (D−d)/2 | 12.5 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) | 17 of 46 |
| Bore above smallest 51100-series size | 70 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 51116-SKF | SKF | full Dimensions and internal design equivalent — standard interchange. | Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier. |
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 51116 model number is decoded
51116 is the 80 mm member of NTN's light-section 51100 thrust family: 105 mm across the washers, 19 mm tall. Decoding 51116: 511 is the dimension series (light-section 51100 thrust family), with 16 encodes the 80 mm bore (bore code x 5). The static margin, C0a 141 kN against Ca 44.5 kN, is what carries slow oscillating or shock thrust without permanent raceway dents. Where misalignment between shaft and housing seats is expected, the spherical-seat washer executions (listed separately in the catalogue) absorb what the flat-seat 51116 cannot. The housing washer needs radial freedom in its seat so the bearing can centre itself; clamping it radially defeats the self-centring the loose fit is designed to give.
Typical equipment & failure modes
Common applications
- heavy press and forging-machine thrust seats
- ship winch and capstan thrust shafts
- crusher main-shaft thrust supports
- large rotary-table and index-table thrust rings
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
- edge loading from a shaft washer mounted off-centre, cutting the contact ellipse short at one side of the track
- washer face corrosion under long standstill in humid service, later printed into the raceway as evenly spaced pitting
Selection pitfalls — read before you substitute
- At 80 mm bore the washers are heavy enough to sag out of square during assembly — support the stack horizontally where possible and verify face runout before loading.
- The 511 light section is the speed-friendly end of the thrust-ball plan — for the same 80 mm bore it gives up load to gain OD, height and limiting-speed headroom.
- The C0a of 141 kN is a static rating: sizing continuous working thrust from C0a alone overstates what the raceway survives.
- A housing washer pressed tight in its seat cannot self-centre; the resulting eccentric running shows up as cage wear long before raceway fatigue.
- Shock thrust above C0a 141 kN leaves dents that later become fatigue origins — crane-hook and press applications need the static check, not just the life calculation.
- The Ca 44.5/C0a 141 kN ratings and 6.35 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 51116; 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 51116?
51116 is a single-direction thrust ball bearing to ISO 104: 80 mm shaft-washer bore, 105 mm outside diameter, 19 mm stack height (3.15 x 4.134 x 0.748 in). From NTN Ball and Roller Bearings CAT.No.2203E: axial Ca 44.5 kN, C0a 141 kN and a 6.35 kN fatigue load limit Pu; the grease limiting speed is 2,200 r/min and the oil rating 3,100 r/min; mass about 422 g.
How is the 51116 designation structured?
511 is the dimension series (light-section 51100 thrust family); 16 encodes the 80 mm bore (bore code x 5). The 105 mm OD and 19 mm height follow the ISO 104 boundary plan for that series.
Can 51116 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 51116?
At the 2,200 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 51116?
The 80/105/19 mm envelope is ISO 104 interchangeable, but washer bore codes, raceway osculation and ratings are maker-specific. Re-verify Ca 44.5 kN / C0a 141 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.