61826-NSK bearing: complete specifications & equivalents
The 61826-NSK is a ISO 15 radial bearing sized 130 x 165 x 18 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NSK |
| Bore diameter d | 130 mm |
| Outer diameter D | 165 mm |
| Width B | 18 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 40.5 kN |
| Basic static load rating C0 | 44 kN |
| Operating temperature | -40 to +150 °C |
| Mass | 758 g |
| Manufacturer designation | NSK 6826 |
| Standard | ISO 15 |
| Catalog version | NSK Rolling Bearings E1103 Part C |
| Last verified | 2026-09-24 |
Source: catalog reference (NSK Rolling Bearings E1103 Part C) · extracted 2026-09-24
Dimensions in inches & 61800-series range
| Bore d | 5.118 in |
|---|---|
| Outer diameter D | 6.496 in |
| Width B | 0.709 in |
| ISO bore code | 26 |
| Radial section height (D−d)/2 | 17.5 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) | 35 of 74 |
| Bore above smallest 61800-series size | 129 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 61826-FAG | FAG | full Dimensions and internal design equivalent — standard interchange. | Same 130×165×18 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61826-NTN | NTN | full Dimensions and internal design equivalent — standard interchange. | Same 130×165×18 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61826-2RS-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 130×165×18 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61826-ZZ-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 130×165×18 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61826 | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 130×165×18 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61826-2RS | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 130×165×18 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting. |
| 61826-RSR | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 130×165×18 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 61826-NSK model number is decoded
In the 61800-series (diameter series 8 of ISO 15) the last two digits encode the bore: 61826 carries bore code 26 = 130 mm. Outside diameter 165 mm and width 18 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 130 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 NSK catalogue this open execution carries the bare designation; protected variants are ordered separately with suffixes ZZ (steel shields), VV (non-contact rubber seals) and DDU (contact rubber seals).
Typical equipment & failure modes
Common applications
- packaging machinery
- space-constrained gearboxes
- clutch and transmission assemblies
- robotics and automation joints
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 130 mm bore the ring mass is significant: heat 61826 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 130 mm bore has only a 17.5 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 6226.
- The open 61826-NSK has no lubricant retention: grease escapes and contaminants migrate straight into the 130×165×18 mm raceway, so specify a sealed arrangement for dusty or washdown duty.
- Storage matters for open bearings: 61826-NSK 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.
- Axial location must clamp the ring face, not the seal area: a shoulder or circlip bearing on the seal side of the 18 mm-wide ring of 61826-NSK drags the lip and overheats it.
- Suffixes stack in a defined order — clearance follows the seal code, e.g. 61826-NSK-C3. No clearance suffix means normal CN clearance.
- The open 61826 has no integral sealing; in the NSK E1103 catalogue the protected variants carry suffixes ZZ (non-contact steel shields), VV (non-contact rubber seals) and DDU (contact rubber seals). NSK does not offer a low-torque contact seal equivalent to NTN's LLH in this catalogue — for high-speed sealed duty specify the VV non-contact seal and an external housing labyrinth.
- The 130 mm bore places 61826 at the lower end of NSK's large-size range; at these diameters the pressed-steel cage is speed-limited and NSK commonly supplies a machined brass cage (suffix M) as an option. Verify cage material and relubrication interval with the NSK distributor, and do not extrapolate small-bore speed ratings to this size.
- NSK rates 61826 at 40.5 kN dynamic (C) and 44 kN static (C0); this upper-medium rating covers conveyor and gearbox drives, but at these loads the pressed-steel cage can be the limiting factor under shock — consider the machined brass cage (suffix M) for impact duty.
- At 758 g, 61826 requires a soft-jaw vise or arbor press for mounting — never hammer it onto the shaft, and support the opposite ring to avoid brinelling the raceways.
- The 130×165×18 mm envelope of 61826 gives a D/d ratio of 1.27 and only 17.5 mm radial section height — this is an ultra-thin section in NSK's E1103 catalogue 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 40.5/44 kN load ratings, mass 758 g here are NSK Rolling Bearings E1103 Part C catalogue figures for 6826 on the 130×165×18 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 61826 in a rated drive. NSK does not tabulate reference or limiting speeds in the E1103 Part C dimension tables used for this page — consult NSK's separate speed-rating tables before high-speed service.
- When replacing a failed unit, inspect the shaft and housing seats before fitting the new 61826 — a new bearing pressed onto a worn or oval seat reproduces the original failure mode in a fraction of its expected life.
- NSK does not recommend washing new shielded or sealed bearings; the rust-preventive film on open units is compatible with standard lithium greases and needs no removal unless the application demands a special fill.
Frequently asked questions
What are the dimensions of a 61826-NSK bearing?
A 61826-NSK deep-groove ball bearing has a 130 mm bore, 165 mm outer diameter and 18 mm width (5.118 × 6.496 × 0.709 in), per ISO 15 boundary dimensions. It is an open bearing with no seals or shields.
How does the 61800 compare with other series at the same 130 mm bore?
618 is an extra-thin section: 165×18 mm, only 17.5 mm radial section at 130 mm bore, far smaller than a 6226, for space-limited layouts at the cost of load rating and misalignment tolerance.
Are 61826 bearings from different brands interchangeable?
For boundary dimensions, yes: every brand's 61826 uses the same ISO 15 envelope (130×165×18 mm). Load ratings, limiting speeds, clearance, precision class and sealing design can differ, so verify those in the supplier catalogue when substituting.
What is the NSK order number for an open 61826?
NSK lists the open 61826 under the bare designation 6826; protected versions use suffixes ZZ (steel shields), VV (non-contact rubber seals) and DDU (contact rubber seals) on the same 130 mm bore envelope.
Does the manufacturing plant affect 6826?
NSK produces standard deep-groove sizes in several plants worldwide to the same drawing; the origin on the box label does not change the ISO 15 envelope or the E1103 catalogue ratings quoted here.
Reviewed & verified by the MPN Base engineering desk against source catalog NSK Rolling Bearings E1103 Part C on 2026-09-24. Read our editorial & correction policy.