51416 bearing: complete specifications & equivalents

The 51416 is a ISO 104 radial bearing sized 80 x 170 x 68 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.

Bearing dimension schematic Front view shows outer diameter D and bore d; side section shows width B. D = 170 mm d = 80 B = 68 mm side section front view
Principal dimensions: bore d 80 mm, outer diameter D 170 mm, width B 68 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand NTN
Bore diameter d 80 mm
Outer diameter D 170 mm
Width B 68 mm
Seal / shield open
Basic dynamic load rating C 270 kN
Basic static load rating C0 620 kN
Fatigue load limit Pu 25 kN
Limiting speed (mechanical) 890 rpm
Mass 7770 g
Manufacturer designation 51416
Standard ISO 104
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 & 51400-series range

Bore d 3.15 in
Outer diameter D 6.693 in
Width B 2.677 in
ISO bore code 16
Radial section height (D−d)/2 45 mm
Smallest bore in 51400-series 25 mm
Largest outer diameter in 51400-series 210 mm
Width range across 51400-series 24–85 mm
Bore position in 51400-series (smallest first) 12 of 15
Bore above smallest 51400-series size 55 mm

Cross references & equivalents

No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.

How the 51416 model number is decoded

In the 51400-series (ISO 104 dimension series) the leading digits 514 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51416 carries bore code 16 = 80 mm. The ISO 104 boundary dimensions are 80 mm bore, 170 mm outside diameter and 68 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.

Typical equipment & failure modes

Common applications

  • gearbox and reducer thrust management
  • conveyor and elevator thrust washers
  • machine tool spindle axial positioning
  • paper mill roll axial restraint

Known failure patterns

  • washer seat fretting from a loose housing or shaft fit
  • rolling-contact fatigue spalling after the rated L10 life is exceeded
  • cage wear or fracture from sustained vibration or shock loading

Selection pitfalls — read before you substitute

  • At a 80 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.
  • The 514xx heavy section at 80 mm bore (170 mm OD) is built for high-load, lower-speed duty; specifying it in a high-rpm application gives excess heat and short grease life — use 511/512 there.
  • Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component.
  • Thrust ball bearings carry axial load only — never apply radial load to 51416; the flat washers will skid and score.

Frequently asked questions

What are the dimensions of a 51416 thrust ball bearing?

A 51416 thrust ball bearing has a 80 mm bore, 170 mm outside diameter and 68 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly.

How does the 51416 bore code work?

The last two digits of 51416 are bore code 16, giving 16 × 5 = 80 mm bore. The 170 mm outside diameter and 68 mm height follow the ISO 104 dimension series, not the bore code alone.

Can a 51416 thrust ball bearing carry radial load?

No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller).

How does the 51400 compare with other thrust series at the same 80 mm bore?

The 514xx is the heavy section: 170×68 mm, 45.0 mm radial section at 80 mm bore — the highest-capacity single-direction thrust option here, aimed at lower-speed, high-load shafts.

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.