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.
Specification table
| Parameter | Value |
|---|---|
| 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 |
| 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 |
| Mass | 12300 g |
| Manufacturer designation | NTN 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 d | 14.173 in |
|---|---|
| Outer diameter D | 17.323 in |
| Width B | 1.496 in |
| ISO bore code | 72 |
| Radial section height (D−d)/2 | 40 mm |
| Smallest bore in 61800-series | 10 mm |
| Largest outer diameter in 61800-series | 600 mm |
| Width range across 61800-series | 5–56 mm |
| Bore position in 61800-series (smallest first) | 40 of 46 |
| Bore above smallest 61800-series size | 350 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 61872 | ISO-INTERCHANGE | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension interchange; ratings above are NTN 2203-3/E values and differ by brand — verify 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 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
- 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
- cage damage from operation beyond the limiting speed
- electrical pitting in VFD-driven motors without grounding protection
Selection pitfalls — read before you substitute
- Mount this 360 mm bore bearing by heating the inner ring (induction heater, max 120 °C) — never drive it home through the outer ring or balls, that brinells the raceways.
- The 618xx thin section at 360 mm bore has only a 40.0 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 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.
- 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 61872 units.
- Suffixes stack in a defined order — clearance follows the seal code, e.g. 61872-C3. No clearance suffix means normal CN clearance.
- 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 (as printed for some thin-section sizes) denotes a pressed-steel cage, not a seal.
- The 207/258 kN load ratings, 8.55 kN fatigue load limit Cu and 12300 g mass here are NTN Ball and Roller Bearings CAT.No.2203-3/E figures for 6872; this seal/size combination has no counterpart from another catalogue on this site, so the page rests on a single manufacturer source — internal geometry and ratings legitimately differ between brands, so re-verify before substituting in a rated drive.
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.
How does the 61872 bore code work?
The last two digits of 61872 are bore code 72, giving 72 × 5 = 360 mm bore. The 440 mm outside diameter and 38 mm width follow the ISO 15 diameter series, not the bore code alone.
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 designation and catalogue data for 61872?
In the NTN Ball and Roller Bearings catalogue (CAT.No.2203-3/E, 2024) this size is listed as 6872 — the open (unsealed) execution, 360×440×38 mm per ISO 15. Quoted values: C 207 kN, C0 258 kN, Cu 8.55 kN, mass 12300 g. Grease limiting speed 1200 rpm. The industry-neutral page spelling 61872 follows the seal-suffix convention used across this site, not NTN order-number spelling.
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.