61852-NTN bearing: complete specifications & equivalents

The 61852-NTN is a ISO 15 radial bearing sized 260 x 320 x 28 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 = 320 mm d = 260 B = 28 mm side section front view
Principal dimensions: bore d 260 mm, outer diameter D 320 mm, width B 28 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand NTN
Bore diameter d 260 mm
Outer diameter D 320 mm
Width B 28 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage steel, stamped ribbon (J-type)
Basic dynamic load rating C 96.5 kN
Basic static load rating C0 120 kN
Fatigue load limit Pu 4.65 kN
Limiting speed (mechanical) 1700 rpm
Operating temperature -40 to +120 °C
Mass 5000 g
Manufacturer designation 6852
Standard ISO 15
Catalog version NTN Ball and Roller Bearings CAT.No.2203-3/E (2024)
Last verified 2026-09-25

Source: catalog reference (NTN Ball and Roller Bearings CAT.No.2203-3/E (2024)) · extracted 2026-09-25

Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN Ball and Roller Bearings 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 & 61800-series range

Bore d10.236 in
Outer diameter D12.598 in
Width B1.102 in
ISO bore code52
Radial section height (D−d)/230 mm
Smallest bore in 61800-series1 mm
Largest outer diameter in 61800-series1820 mm
Width range across 61800-series1–140 mm
Bore position in 61800-series (smallest first)45 of 74
Bore above smallest 61800-series size259 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
61852-FAG FAG full
Dimensions and internal design equivalent — standard interchange.
Same 260×320×28 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
61852 SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 260×320×28 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.

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 61852-NTN model number is decoded

In the 61800-series (diameter series 8 of ISO 15) the last two digits encode the bore: 61852 carries bore code 52 = 260 mm. Outside diameter 320 mm and width 28 mm come from the ISO 15 boundary-dimensions general plan. With no seal suffix the bearing is open: no shields or seals are fitted and lubrication is supplied by the application. For normal-load mounting with a rotating inner ring on a 260 mm shaft, typical catalogue practice is a m6 shaft seat with an H7 housing bore — verify against the actual load direction and magnitude. In the NTN catalogue this open execution carries the bare designation; protected variants are ordered separately with suffixes ZZ (shields), LLB/LLF (non-contact seals), LLH (low-torque contact seal) and LLU (contact seal).

Typical equipment & failure modes

Common applications

  • robotics and automation joints
  • lay shafts and idler shafts
  • textile machinery
  • packaging machinery

Known failure patterns

  • contamination wear from dust and dirt ingress through the open arrangement
  • lubricant starvation when no regreasing interval is maintained
  • fretting corrosion on a loose shaft seat
  • cage damage from operation beyond the limiting speed

Selection pitfalls — read before you substitute

  • At 260 mm bore the ring mass is significant: heat 61852 on an induction heater (max 120 °C), never over an open flame, and plan puller access or a withdrawal sleeve now for the day it has to come off again.
  • The 618xx thin section at 260 mm bore has only a 30.0 mm radial section height: it saves space but is highly sensitive to misalignment, shaft deflection and shock loads — verify shaft stiffness before choosing it over a 6252.
  • Storage matters for open bearings: 61852-NTN leaves the factory with rust preventive only, so clean it and apply the service grease at assembly even if the rings look oily from the wrapper.
  • Open bearings tolerate the highest speeds in the 61800-series but need a defined regreasing interval; run-to-failure lubrication is the dominant cause of early failure in open 61852 units.
  • Do not quieten a noisy bearing by preloading it: the 61800-series is a deep-groove design, not angular-contact; axial preload raises temperature and shortens grease life.
  • Assign fits by which ring rotates: an interference shaft fit for a rotating inner ring; if the outer ring rotates instead, reverse the logic — a loose rotating ring creeps and frets its seat.
  • The open 61852 has no integral sealing; in the NTN 2203 catalogue the protected variants carry suffixes ZZ (non-contact steel shields), LLB/LLF (non-contact rubber seals), LLU (contact rubber seals) and LLH (a low-torque contact seal with higher speed capability than LLU). A JR or JRX suffix (printed for some thin-section sizes) denotes a pressed-steel cage, not a seal.
  • The 260 mm bore places 61852 in NTN's upper large-size range; centrifugal force at this diameter sharply caps the grease limiting speed, so NTN usually supplies a machined brass cage (suffix M) and expects oil lubrication for continuous duty. Confirm relubrication interval and cage material with the NTN distributor.
  • NTN lists the grease limiting speed at 1700 r/min for 61852; this is a large or heavy-section size where centrifugal force and cage inertia cap the speed — for higher shaft speeds either step to a smaller bearing on the same bore or consult NTN for an oil-lubricated, machined-cage variant.
  • At 96.5 kN dynamic load rating (C) and 120 kN static (C0), 4.65 kN fatigue load limit Cu, 61852 is a heavy-load bearing for industrial gearboxes and large conveyors; NTN expects a machined brass cage (suffix M) at this rating for shock duty, and the static C0 must be checked against any mounting or lifting loads.
  • At 5000 g (5.0 kg), 61852 is a heavy bearing that requires a crane or hoist for handling; induction-heat the inner ring (max 120 °C) and use a mechanical puller for removal — never apply heat directly to the balls or cage.
  • The 260×320×28 mm envelope of 61852 gives a D/d ratio of 1.23 and only 30.0 mm radial section height — this is an ultra-thin section where shaft deflection and housing ovality directly load the ball-raceway contact; verify shaft stiffness (target deflection under 0.05 mm) before specifying it over a 62-series.
  • The 96.5/120 kN load ratings, 4.65 kN fatigue load limit Cu NTN lists the grease limiting speed at 1700 r/min for this designation; oil-mist or jet lubrication raises the ceiling but requires a sealed-housing review. and 5000 g mass here are NTN Ball and Roller Bearings CAT.No.2203-3/E figures for 6852 on the 260×320×28 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 61852 in a rated drive.
  • Order the C3 internal-clearance version (61852 with C3 after the seal code) when the shaft fit is tight or the shaft-to-housing temperature gradient exceeds roughly 10 °C — the residual clearance after mounting, not the catalogue CN figure, decides service life.
  • NTN's pressed-steel cage (no cage suffix) is the quiet standard for this size; for sustained running close to the limiting speed or for heavy shock duty, ask the NTN channel whether a machined-cage execution of 61852 is listed.

Frequently asked questions

What are the dimensions of a 61852-NTN bearing?

A 61852-NTN deep-groove ball bearing has a 260 mm bore, 320 mm outer diameter and 28 mm width (10.236 × 12.598 × 1.102 in), per ISO 15 boundary dimensions. It is an open bearing with no seals or shields.

What internal clearance does 61852-NTN have?

Unless a clearance suffix says otherwise, 61852-NTN is manufactured to normal (CN) radial internal clearance. Tight fits and hot shafts consume clearance in service — for those conditions order the C3 execution of 61852 and verify the residual clearance after mounting.

How should 61852-NTN be mounted?

Apply the mounting force to the ring being fitted: on a 260 mm shaft seat the press load must pass through the inner-ring face only. Induction heating of the inner ring (max 120 °C) is the clean method at this size. Never strike the outer ring, the cage or the seals.

What is the NTN order number for an open 61852?

NTN lists the open 61852 under the bare designation 6852; protected versions use suffixes ZZ (shields), LLB/LLF (non-contact seals), LLH (low-torque contact seal) and LLU (contact seal) on the same 260 mm bore envelope.

Is 6852 a current NTN production size?

The NTN 2203-series catalogue lists it as a standard size; availability of specific seal executions (ZZ, LLB/LLF, LLH, LLU) varies by region and stock — confirm with an NTN distributor before specifying spares.

Reviewed & verified by the MPN Base engineering desk against source catalog NTN Ball and Roller Bearings CAT.No.2203-3/E (2024) on 2026-09-25. Read our editorial & correction policy.