1312K bearing: complete specifications & equivalents

The 1312K is a ISO 15 radial bearing sized 60 x 130 x 31 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 = 130 mm d = 60 B = 31 mm side section front view
Principal dimensions: bore d 60 mm, outer diameter D 130 mm, width B 31 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand NTN
Bore diameter d 60 mm
Outer diameter D 130 mm
Width B 31 mm
Seal / shield open
Basic dynamic load rating C 57.5 kN
Basic static load rating C0 20.8 kN
Fatigue load limit Pu 0.51 kN
Limiting speed (mechanical) 4500 rpm
Mass 2000 g
Manufacturer designation 1312SK
Standard ISO 15
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 & 1300-series range

Bore d 2.362 in
Outer diameter D 5.118 in
Width B 1.22 in
ISO bore code —
Radial section height (D−d)/2 35 mm
Smallest bore in 1300-series 10 mm
Largest outer diameter in 1300-series 240 mm
Width range across 1300-series 11–50 mm
Bore position in 1300-series (smallest first) 13 of 23
Bore above smallest 1300-series size 50 mm

Cross references & equivalents

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

How the 1312K model number is decoded

In the 1300-series (ISO 15 dimension series) the leading digits 13 mark a double-row self-aligning ball bearing and the last two digits encode the bore: 1312 carries bore code 12 = 60 mm. Outside diameter 130 mm and width 31 mm follow the ISO 15 general plan. The K suffix denotes a 1:12 tapered bore for mounting on an adapter sleeve or tapered shaft seat; the cylindrical-bore equivalent is 1312. Two rows of balls run on a common sphered outer raceway, allowing the inner ring to pivot and compensate for shaft deflection or housing misalignment.

Typical equipment & failure modes

Common applications

  • conveyor and material handling drives
  • textile and printing machine spindles
  • paper mill and processing equipment shafts
  • industrial electric motor shafts

Known failure patterns

  • contamination wear from dust and dirt ingress through the open arrangement
  • lubricant starvation when no regreasing interval is maintained
  • raceway smearing under marginal lubrication at start-up
  • fretting corrosion on a loose shaft seat

Selection pitfalls — read before you substitute

  • Temperature rise and interference fits consume internal clearance on this 60 mm bore: a CN bearing on a tight, hot shaft can lose all residual clearance — size 1312 with C3 for those conditions.
  • The 13xx medium section at 60 mm bore gains rating through a larger 130 mm OD and 31 mm width; verify the housing accepts the larger envelope before substituting for a 1212.
  • Tapered-bore 1312K requires a matching adapter sleeve (e.g. H2xx for small bores, H3xx for larger); verify the sleeve bore code matches the 60 mm shaft before ordering.
  • The adapter sleeve adds length and a small radial step; check that the housing bore and shaft shoulder clear the sleeve nut and that the withdrawal nut is accessible for future dismounting.
  • Do not use a self-aligning ball bearing where high radial rigidity is required — the sphered outer raceway allows more radial movement than a deep-groove or cylindrical roller bearing.

Frequently asked questions

What are the dimensions of a 1312K self-aligning ball bearing?

A 1312K self-aligning ball bearing has a 60 mm bore, 130 mm outer diameter and 31 mm width, per ISO 15 boundary dimensions. The K suffix indicates a 1:12 tapered bore for adapter-sleeve mounting; the cylindrical-bore version is 1312.

How does the 1312 bore code work?

The last two digits of 1312 are bore code 12, giving 12 × 5 = 60 mm bore. The 130 mm outside diameter and 31 mm width follow the ISO 15 diameter series, not the bore code alone.

What does the K suffix mean on 1312K?

The K suffix denotes a 1:12 tapered bore for mounting with an adapter sleeve. The cylindrical-bore equivalent is 1312. Adapter sleeves are sold separately and must match the bore code.

How does the 1300 compare with other self-aligning series at the same 60 mm bore?

The 13xx is the medium section: 130×31 mm, 35.0 mm radial section at 60 mm bore, carrying more load than a 1212 but needing a larger housing bore.

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.