61872 bearing: complete specifications & equivalents

The 61872 is a ISO 15 radial bearing sized 360 x 440 x 38 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 = 440 mm d = 360 B = 38 mm side section front view
Principal dimensions: bore d 360 mm, outer diameter D 440 mm, width B 38 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand NTN
Bore diameter d 360 mm
Outer diameter D 440 mm
Width B 38 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage steel, stamped ribbon (J-type)
Basic dynamic load rating C 207 kN
Basic static load rating C0 258 kN
Fatigue load limit Pu 8.55 kN
Limiting speed (mechanical) 1200 rpm
Operating temperature -40 to +120 °C
Mass 12300 g
Manufacturer designation 6872
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 d14.173 in
Outer diameter D17.323 in
Width B1.496 in
ISO bore code72
Radial section height (D−d)/240 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)50 of 74
Bore above smallest 61800-series size359 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
61872-MA SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 360×440×38 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 61872 model number is decoded

In the 61800-series (diameter series 8 of ISO 15) the last two digits encode the bore: 61872 carries bore code 72 = 360 mm. Outside diameter 440 mm and width 38 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 360 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

  • lay shafts and idler shafts
  • textile machinery
  • packaging machinery
  • space-constrained gearboxes

Known failure patterns

  • contamination wear from dust and dirt ingress through the open arrangement
  • lubricant starvation when no regreasing interval is maintained
  • cage damage from operation beyond the limiting speed
  • electrical pitting in VFD-driven motors without grounding protection

Selection pitfalls — read before you substitute

  • Large bores like the 360 mm of 61872 demand clean, burr-free seats; one raised burr under a ring this size cocks the bearing and concentrates load at the raceway edge, cutting life drastically.
  • Only 40.0 mm of radial section separates bore and OD on the 618xx series at 360 mm: ring flex from clamping or an oval housing bore transfers straight into raceway stress, so seat roundness matters more here than on a 6272.
  • The open 61872 has no lubricant retention: grease escapes and contaminants migrate straight into the 360×440×38 mm raceway, so specify a sealed arrangement for dusty or washdown duty.
  • Storage matters for open bearings: 61872 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.
  • Suffixes stack in a defined order — clearance follows the seal code, e.g. 61872-C3. No clearance suffix means normal CN clearance.
  • A 360 mm bore listing showing the right d/D/B but no standard or precision-class reference may be a loose-tolerance import; measure bore/OD spread before fitting it to a machined shaft.
  • The open 61872 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 360 mm bore places 61872 in NTN's maximum-size range at the lower end; this is a heavy-engineering bearing where centrifugal force and cage inertia dominate the design envelope. NTN supplies a machined brass cage (suffix M) and expects oil lubrication; do not use catalogue grease speed figures for this size without an NTN engineering review.
  • NTN lists the grease limiting speed at 1200 r/min for 61872; this is a large-section size where the pressed-steel cage is speed-limited — NTN recommends the machined brass cage (suffix M) and oil lubrication for any continuous operation above this figure.
  • At 207 kN dynamic load rating (C) and 258 kN static (C0), 8.55 kN fatigue load limit Cu, 61872 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 12300 g (12.3 kg), 61872 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 360×440×38 mm envelope of 61872 gives a D/d ratio of 1.22 and only 40.0 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 207/258 kN load ratings, 8.55 kN fatigue load limit Cu NTN lists the grease limiting speed at 1200 r/min for this designation; oil-mist or jet lubrication raises the ceiling but requires a sealed-housing review. and 12300 g mass here are NTN Ball and Roller Bearings CAT.No.2203-3/E figures for 6872 on the 360×440×38 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 61872 in a rated drive.
  • Factory-fill grease in NTN sealed units is a general-duty lithium-soap grease; food-grade, low-temperature and high-temperature fills are request options at order time, because LLU/LLB units are not meant to be opened and re-greased in the field.
  • Standard catalogue stock of 61872 is the general-purpose execution; for low-noise motor duty NTN offers low-torque seal and special-grease variants in this size class, which are separate order numbers.

Frequently asked questions

What are the dimensions of a 61872 bearing?

A 61872 deep-groove ball bearing has a 360 mm bore, 440 mm outer diameter and 38 mm width (14.173 × 17.323 × 1.496 in), per ISO 15 boundary dimensions. It is an open bearing with no seals or shields.

What does no suffix on 61872 mean?

A bare 61872 designation means open: no shields or seals, normal CN radial clearance and P0 normal tolerance unless further suffixes are ordered. The application must supply and retain the lubrication.

How does the 61800 compare with other series at the same 360 mm bore?

618 is an extra-thin section: 440×38 mm, only 40.0 mm radial section at 360 mm bore, far smaller than a 6272, for space-limited layouts at the cost of load rating and misalignment tolerance.

What is the NTN order number for an open 61872?

NTN lists the open 61872 under the bare designation 6872; protected versions use suffixes ZZ (shields), LLB/LLF (non-contact seals), LLH (low-torque contact seal) and LLU (contact seal) on the same 360 mm bore envelope.

What cage does NTN fit in 6872?

Standard is a pressed-steel cage with no suffix; larger sizes or shock-loaded duty can be supplied with a machined brass cage (suffix M) as a separate order number. The catalogue figures quoted here are for the pressed-steel execution.

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.