61813-NTN bearing: complete specifications & equivalents
The 61813-NTN is a ISO 15 radial bearing sized 65 x 85 x 10 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 65 mm |
| Outer diameter D | 85 mm |
| Width B | 10 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 12.8 kN |
| Basic static load rating C0 | 11 kN |
| Fatigue load limit Pu | 0.73 kN |
| Limiting speed (mechanical) | 7400 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 128 g |
| Manufacturer designation | 6813 |
| 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 | 2.559 in |
|---|---|
| Outer diameter D | 3.346 in |
| Width B | 0.394 in |
| ISO bore code | 13 |
| Radial section height (D−d)/2 | 10 mm |
| Smallest bore in 61800-series | 1 mm |
| Largest outer diameter in 61800-series | 1820 mm |
| Width range across 61800-series | 1–140 mm |
| Bore position in 61800-series (smallest first) | 24 of 74 |
| Bore above smallest 61800-series size | 64 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 61813-2RS-NSK | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 65×85×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61813-RSR-NSK | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 65×85×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61813-ZZ | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 65×85×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61813-NSK | NSK | full Dimensions and internal design equivalent — standard interchange. | Same 65×85×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61813 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 65×85×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61813-2RS | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 65×85×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61813-RSR | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 65×85×10 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 61813-NTN model number is decoded
61813 is supplied open, without shields or seals, so the arrangement around it must supply and retain the lubricant. Within the extra-thin 618xx section (diameter series 8 of ISO 15), multiplying bore code 13 by five gives the 65 mm bore; the 85 mm outside diameter and 10 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 65 mm shaft under normal load, catalogue practice seats it on a k5 shaft fit with an H7 housing bore — confirm against the actual load direction and magnitude before committing. 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
- brinelling from static overload or hammering during mounting
- false brinelling from vibration while the shaft is stationary
Selection pitfalls — read before you substitute
- At 65 mm bore, induction heating to roughly 80–100 °C is the clean mounting method; never exceed 120 °C, and hold 61813 against the shaft shoulder while it cools so the ring cannot creep back.
- Only 10.0 mm of radial section separates bore and OD on the 618xx series at 65 mm: ring flex from clamping or an oval housing bore transfers straight into raceway stress, so seat roundness matters more here than on a 6213.
- The open 61813-NTN has no lubricant retention: grease escapes and contaminants migrate straight into the 65×85×10 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 61813 units.
- The housing bore for the 85 mm OD should be round within IT7; an oval bore pinches the outer ring of 61813-NTN and shows up later as two-point loaded raceway wear.
- Suffixes stack in a defined order — clearance follows the seal code, e.g. 61813-NTN-C3. No clearance suffix means normal CN clearance.
- The open 61813 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.
- At 65 mm bore 61813 is in NTN's upper general-purpose range; the pressed-steel cage is standard but mid-section 63xx sizes at this bore can be ordered with a machined brass cage (suffix M) for heavy-shock or very-low-speed duty — confirm cage material with the NTN channel if the application sees impact loads.
- At 7400 r/min the grease limiting speed for 61813 covers medium-duty industrial drives; the open or shielded execution can run continuously at this speed with standard lithium-soap grease.
- NTN rates 61813 at 12.8 kN dynamic (C) and 11 kN static (C0), 0.73 kN fatigue load limit Cu; this light-to-medium rating suits fractional-horsepower drives and instruments — for conveying or gearbox duty with shock loads, verify the equivalent dynamic load stays well below C.
- At 128 g, 61813 is light enough for hand assembly but should be pressed on with a fitting sleeve against the inner ring; do not strike the outer ring or cage with a hammer.
- The 65×85×10 mm envelope of 61813 gives a D/d ratio of 1.31 and only 10.0 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 12.8/11 kN load ratings, 0.73 kN fatigue load limit Cu NTN lists the grease limiting speed at 7400 r/min for this designation; oil-mist or jet lubrication raises the ceiling but requires a sealed-housing review. and 128 g mass here are NTN Ball and Roller Bearings CAT.No.2203-3/E figures for 6813 on the 65×85×10 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 61813 in a rated drive.
- 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 61813 is listed.
- Two NTN bearings of the same designation from different production lots can carry minor internal-geometry revisions; for paired or preloaded arrangements on one shaft, order a single lot through the NTN distributor.
Frequently asked questions
What are the dimensions of a 61813-NTN bearing?
A 61813-NTN deep-groove ball bearing has a 65 mm bore, 85 mm outer diameter and 10 mm width (2.559 × 3.346 × 0.394 in), per ISO 15 boundary dimensions. It is an open bearing with no seals or shields.
How should 61813-NTN be mounted?
Apply the mounting force to the ring being fitted: on a 65 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 lubrication does 61813-NTN need?
The open 61813-NTN is lubricated by the application; a NLGI 2 lithium-soap grease filled to roughly 25–35% of the free volume is the common choice, with a defined relubrication interval.
What is the NTN order number for an open 61813?
NTN lists the open 61813 under the bare designation 6813; protected versions use suffixes ZZ (shields), LLB/LLF (non-contact seals), LLH (low-torque contact seal) and LLU (contact seal) on the same 65 mm bore envelope.
Does NTN offer 61813 with C3 clearance?
Yes — most NTN deep-groove sizes can be ordered with C3 internal clearance (suffix C3 follows the seal code). C3 suits tight fits and hot shafts; for normal fits at moderate temperature the standard CN clearance of 6813 is the correct choice.
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.