61820-RSR bearing: complete specifications & equivalents

The 61820-RSR is a ISO 15 radial bearing sized 100 x 125 x 13 mm (bore x OD x width) with RSR sealing. 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 = 125 mm d = 100 B = 13 mm side section front view
Principal dimensions: bore d 100 mm, outer diameter D 125 mm, width B 13 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand SKF
Bore diameter d 100 mm
Outer diameter D 125 mm
Width B 13 mm
Material GCr15
Seal / shield RSR
Internal clearance CN / C3 available
Tolerance class P0
Cage steel, stamped ribbon (J-type)
Basic dynamic load rating C 17.8 kN
Basic static load rating C0 18.3 kN
Fatigue load limit Pu 0.95 kN
Reference speed (thermal) 10000 rpm
Limiting speed (mechanical) 5300 rpm
Operating temperature -30 to +120 °C
Mass 320 g
Manufacturer designation SKF 61820-2RZ
Standard ISO 15
Catalog version SKF PUB BU/P1 17000/1 EN (Oct 2018)
Last verified 2026-09-24

Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018)) · extracted 2026-09-24

Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018)); SKF® and SKF Explorer® are trademarks of AB SKF, used here for identification only — mpnbase is not an authorized SKF distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at skf.com.

Dimensions in inches & 61800-series range

Bore d3.937 in
Outer diameter D4.921 in
Width B0.512 in
ISO bore code20
Radial section height (D−d)/212.5 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)31 of 74
Bore above smallest 61800-series size99 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
61820-2RS-NSK NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 100×125×13 mm envelope per ISO 15; seal variant (RSR vs 2RS) and load ratings differ — confirm sealing and rating before substituting.
61820-NSK NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 100×125×13 mm envelope per ISO 15; seal variant (RSR vs OPEN) and load ratings differ — confirm sealing and rating before substituting.
61820-RSR-NSK NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 100×125×13 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting.
61820-ZZ NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 100×125×13 mm envelope per ISO 15; seal variant (RSR vs ZZ) and load ratings differ — confirm sealing and rating before substituting.
61820-2RS-NTN NTN partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 100×125×13 mm envelope per ISO 15; seal variant (RSR vs 2RS) and load ratings differ — confirm sealing and rating before substituting.
61820-NTN NTN partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 100×125×13 mm envelope per ISO 15; seal variant (RSR vs OPEN) and load ratings differ — confirm sealing and rating before substituting.
61820-RSR-NTN NTN partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 100×125×13 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting.
61820-ZZ-NTN NTN partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 100×125×13 mm envelope per ISO 15; seal variant (RSR vs ZZ) and load ratings 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 61820-RSR model number is decoded

61820-RSR uses two non-contact elastomer lips with very low drag; coarse debris stays out, but the bearing is not liquid-tight. Within the extra-thin 618xx section (diameter series 8 of ISO 15), multiplying bore code 20 by five gives the 100 mm bore; the 125 mm outside diameter and 13 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 100 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. SKF's low-friction seal suffix is 2RSL/2RZ (this page's industry-neutral spelling is -RSR); catalogue number 61820-2RZ.

Typical equipment & failure modes

Common applications

  • space-constrained gearboxes
  • clutch and transmission assemblies
  • robotics and automation joints
  • lay shafts and idler shafts

Known failure patterns

  • ingress of fine dust or moisture past the non-contact lip in dirty or wet duty (RSR is not liquid-tight)
  • lip-lubricant starvation if the bearing runs dry for extended periods
  • fretting corrosion on a loose shaft seat
  • cage damage from operation beyond the limiting speed

Selection pitfalls — read before you substitute

  • At 100 mm bore the ring mass is significant: heat 61820 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 100 mm bore has only a 12.5 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 6220.
  • The low-drag lip of 61820-RSR barely touches the inner ring; after long shelf storage the grease can separate, so rotate the rings by hand and confirm smooth, silent running before fitting.
  • The non-contact lip of 61820-RSR does not retain a lifetime grease fill the way a contact seal does; confirm the regreasing interval for the 100 mm bore position before relying on it as sealed-for-life.
  • Grease compatibility is not guaranteed between fills: mixing lithium and polyurea thickeners in a 61800-series position can soften the mixture and leak — clean out the old fill before switching grease types.
  • Axial location must clamp the ring face, not the seal area: a shoulder or circlip bearing on the seal side of the 13 mm-wide ring of 61820-RSR drags the lip and overheats it.
  • SKF catalogues the low-friction seal as 61820-2RZ (suffix -2RSL or -2RZ): a non-contact elastomer lip that runs near the open 5300 r/min limiting speed, closer to the open bearing's 10000 r/min reference than the contact-seal version. It keeps coarse debris out without the drag of a contact seal, but is not liquid-tight — use 2RSH for wet or fine-dust positions.
  • The 17.8/18.3 kN ratings here are SKF Explorer-class figures from catalogue PUB BU/P1 17000/1 EN (Oct 2018); SKF can revise internal geometry and ratings without changing the designation, so treat the catalogue version and date as part of the specification and re-verify for critical drives.

Frequently asked questions

What are the dimensions of a 61820-RSR bearing?

A 61820-RSR deep-groove ball bearing has a 100 mm bore, 125 mm outer diameter and 13 mm width (3.937 × 4.921 × 0.512 in), per ISO 15 boundary dimensions. It is fitted with two low-friction non-contact rubber seals.

How does the 61820 bore code work?

The last two digits of 61820 are bore code 20, giving 20 × 5 = 100 mm bore. The 125 mm outside diameter and 13 mm width follow the ISO 15 diameter series, not the bore code alone.

What does the RSR suffix on 61820-RSR mean?

RSR means two low-friction non-contact rubber seals. They keep coarse debris out with minimal drag (speed close to the open bearing) but are not liquid-tight; use -2RS contact seals for wet or fine-dust environments.

How does the 61800 compare with other series at the same 100 mm bore?

618 is an extra-thin section: 125×13 mm, only 12.5 mm radial section at 100 mm bore, far smaller than a 6220, for space-limited layouts at the cost of load rating and misalignment tolerance.

What is the SKF designation and catalogue data for 61820-RSR?

In the SKF Rolling Bearings catalogue this size is listed as 61820-2RZ — two low-friction non-contact elastomer seals, 100×125×13 mm per ISO 15. Quoted values: C 17.8 kN, C0 18.3 kN, Pu 0.95 kN, limiting speed 5300 r/min, mass 320 g. Brand suffixes (2Z, 2RSH, 2RSL) differ from the industry-neutral spelling 61820-RSR.

Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018) on 2026-09-24. Read our editorial & correction policy.