5203SCLLD bearing: complete specifications & equivalents
The 5203SCLLD is a ISO 15 radial bearing sized 17 x 40 x 17.5 mm (bore x OD x width) with 2RS sealing. Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 17 mm |
| Outer diameter D | 40 mm |
| Width B | 17.5 mm |
| Material | GCr15 |
| Seal / shield | 2RS |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 12.7 kN |
| Basic static load rating C0 | 8.3 kN |
| Fatigue load limit Pu | 0.49 kN |
| Limiting speed (mechanical) | 10000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 100 g |
| Manufacturer designation | NTN 5203SCLLD |
| Standard | ISO 15 |
| Catalog version | NTN Ball and Roller Bearings CAT.No.2203E |
| Last verified | 2026-10-01 |
Source: catalog reference (NTN Ball and Roller Bearings CAT.No.2203E) · extracted 2026-10-01
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN Ball and Roller Bearings CAT.No.2203E); 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 & 5200S-series range
| Bore d | 0.669 in |
|---|---|
| Outer diameter D | 1.575 in |
| Width B | 0.689 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 11.5 mm |
| Smallest bore in 5200S-series | 10 mm |
| Largest outer diameter in 5200S-series | 150 mm |
| Width range across 5200S-series | 14.3–49.2 mm |
| Bore position in 5200S-series (smallest first) | 4 of 18 |
| Bore above smallest 5200S-series size | 7 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 5203SCLLD | ISO 15 | verify Commonly quoted cross reference; confirm against the target catalog before ordering. | ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range 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 5203SCLLD model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, 5203SCLLD appears as a medium-duty 5200S double-row family bearing of 17 mm bore, 40 mm outside diameter and 17.5 mm width. Two fields make up the code — 52 is the double-row dimension series (medium-duty 5200S double-row family) and 03 encodes the 17 mm bore (bore code x 5), and CLLD marks the SC internal design with contact rubber seals on both sides. Because the contact line is angled, one bearing of this type takes radial load plus thrust from one direction only — the opposite direction needs a second bearing or a matched set. Where the same envelope must also be sealed, or where mounting mistakes are likely, compare with the double-row 52/53 catalogue pages before fixing the bill of materials. A 17 mm shaft typically takes a j5/k5 fit for rotating inner-ring load; keep the housing bore to G6/H6 class so the contact geometry is not distorted.
Typical equipment & failure modes
Common applications
- servo and stepper motor shafts with axial preload
- bicycle and motorcycle wheel and steering positions
- small gearbox pinion shafts with helical gears
- precision instrument and encoder support shafts
Known failure patterns
- false brinelling on the raceway contact ellipses when a preloaded spindle sits vibrating at standstill — visible as evenly spaced flute-like wear at ball pitch
- loss of preload after housing-fret or shaft creep, leaving the pair loose — ball skidding, cage rattle and a falling natural frequency follow
- pressed-steel cage pocket wear and rivet loosening after repeated ball skid at light load and high speed
- flaking that starts at the raceway shoulder on the thrust-loaded side when axial load repeatedly exceeds the design share
- contamination-induced denting — hard particles rolled into the contact ellipse become the initiation points for surface fatigue
Selection pitfalls — read before you substitute
- At 17 mm bore the rings are thin-sectioned: press force must go through the ring being fitted, never through the balls, or the first damage is already in the raceway before the machine runs.
- Sealed LLD contact-seal executions are grease-for-life: there is no relubrication path, so the grease life calculation replaces the relubrication plan.
- A 5203SCLLD mounted the wrong way round still turns smoothly by hand; the failure shows up weeks later as raceway flaking on the unloaded-looking side.
- The C0 of 8.3 kN is a static rating, not a permissible running thrust — sizing continuous axial load from C0 alone is a recurring drawing-office error.
- The 10,000 r/min speed figure assumes the catalogue lubrication state and a correctly set pair; real limits drop fast with excess grease fill or heavy preload.
- The 12.7/8.3 kN ratings and 0.49 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 5203SCLLD; internal geometry legitimately differs between manufacturers, so re-verify ratings, contact angle and suffix before substituting another make on a rated drive.
Frequently asked questions
What are the dimensions and catalogue ratings of NTN 5203SCLLD?
5203SCLLD is a sealed double-row angular contact ball bearing to ISO 15: 17 mm bore, 40 mm outside diameter, 17.5 mm width (0.669 x 1.575 x 0.689 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 12.7 kN, C0 8.3 kN and a 0.49 kN fatigue load limit Pu; the grease limiting speed is 10,000 r/min and no oil rating is printed for this execution; mass about 100 g.
How is the 5203SCLLD designation structured?
52 is the double-row dimension series (medium-duty 5200S double-row family); 03 encodes the 17 mm bore (bore code x 5), and CLLD marks the SC internal design with contact rubber seals on both sides. The 40 mm OD and 17.5 mm width follow the ISO 15 boundary-dimension plan for that series.
Which axial direction does 5203SCLLD support?
5203SCLLD is a sealed double-row bearing: thrust in both directions, radial and moment load in one envelope, with contact rubber seals (grease-lubricated, no oil speed rating).
What lubrication speeds does NTN print for 5203SCLLD?
Per NTN Ball and Roller Bearings CAT.No.2203E, the grease limiting speed is 10,000 r/min and no oil rating is printed for this execution. These are catalogue ceilings for a correctly mounted bearing with the stated lubricant; preload, fill quantity, ambient heat and paired arrangements all move the real limit.
What should be checked before substituting another make for 5203SCLLD?
The 17/40/17.5 mm envelope is ISO 15 interchangeable, but internal geometry — contact angle, osculation, cage and shoulder details — is maker-specific. Re-verify C 12.7 kN / C0 8.3 kN, the speed figures, contact angle and suffix meaning against the donor catalogue before swapping on a rated drive.
Reviewed & verified by the MPN Base engineering desk against source catalog NTN Ball and Roller Bearings CAT.No.2203E on 2026-10-01. Read our editorial & correction policy.