71917 bearing: complete specifications & equivalents
The 71917 is a ISO 15 radial bearing sized 85 x 120 x 18 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | Generic ISO interchange (unbranded) |
| Bore diameter d | 85 mm |
| Outer diameter D | 120 mm |
| Width B | 18 mm |
| Seal / shield | open |
| Internal clearance | CN / C3 available |
| Tolerance class | P0 |
| Cage | brass |
| Operating temperature | -40 to +150 °C |
| Mass (geometry estimate) | 518 g |
| Standard | ISO 15 |
| Catalog version | iso15-ed4-geometry |
| Last verified | 2026-09-24 |
Source: ISO 15 boundary-dimensions standard · extracted 2026-09-24
Standard-interchange bearing: dimensions per ISO 15; CN clearance, P0 tolerance and a stamped-steel cage are catalogue defaults unless the supplier states otherwise, and mass is a geometry-derived estimate. Brand catalogue load ratings and limiting speeds for 71917 are being backfilled — use the inquiry form for certified values.
Dimensions in inches & 71900-series range
| Bore d | 3.346 in |
|---|---|
| Outer diameter D | 4.724 in |
| Width B | 0.709 in |
| ISO bore code | 17 |
| Radial section height (D−d)/2 | 17.5 mm |
| Smallest bore in 71900-series | 20 mm |
| Largest outer diameter in 71900-series | 140 mm |
| Width range across 71900-series | 9–20 mm |
| Bore position in 71900-series (smallest first) | 14 of 17 |
| Bore above smallest 71900-series size | 65 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the 71917 model number is decoded
In the 71900-series (ISO 15 diameter series 9) the last two digits encode the bore: 71917 carries bore code 17 = 85 mm. Outside diameter 120 mm and width 18 mm come from the ISO 15 boundary-dimensions general plan, shared with the 61917 deep-groove envelope. The '7' prefix marks a single-row angular-contact design with an asymmetric raceway and a nominal 40° contact angle (suffix C); a higher-angle variant carries more axial load, a 25° (E / A5) variant runs faster. For combined radial and axial load with a rotating inner ring on a 85 mm shaft, specify a k5 shaft seat with an H7 housing bore — verify against the load direction and magnitude, and pair two units (DB or DF) for bidirectional thrust.
Typical equipment & failure modes
Common applications
- clutch and idler shafts
- semiconductor handling axes
- packaging machinery
- robotics joint arms
Known failure patterns
- raceway spalling from axial overload exceeding the single-direction thrust rating
- preload loss after a paired set runs loose, letting the balls skid and smear the raceway
- raceway smearing under marginal lubrication at start-up before oil climb reaches the contact
- cage fracture from operation beyond the limiting speed with inadequate lubricant
Selection pitfalls — read before you substitute
- Mount this 85 mm bore angular-contact pair by heating the inner rings (induction heater, max 120 °C) and clocking both faces; never drive a pair home through the outer rings.
- The 719xx thin section (17.5 mm section height at 85 mm bore) trades capacity for compactness; stiff, accurately aligned seats are essential or edge loading will spall the raceway early.
- Draw-up on a thin-section 71917 is lighter than on a 72/73 bearing of the same bore: a 18 mm-wide ring clamps with a controlled light interference, and over-driving it bows the raceway — measure the mounted preload or runout rather than copying heavy-section fit tables.
- Shaft and housing fillets must clear the bearing chamfer so the 18 mm-wide ring seats square; provide an undercut or withdrawal groove instead of relying on an oversized radius.
- Assign fits by which ring rotates: an interference shaft fit for a rotating inner ring; if the outer ring rotates instead, reverse the logic — a loose rotating ring creeps and frets its seat.
Frequently asked questions
What are the dimensions of a 71917 angular-contact bearing?
A 71917 single-row angular-contact ball bearing has a 85 mm bore, 120 mm outer diameter and 18 mm width (3.346 × 4.724 × 0.709 in), per ISO 15 boundary dimensions. It is an open bearing with a nominal 40° contact angle. Geometry-based estimated mass is about 518 g for a brass-cage unit; catalogue masses vary with cage and ball complement.
How does the 71917 bore code work?
The last two digits of 71917 are bore code 17, giving 17 × 5 = 85 mm bore. The 120 mm outside diameter and 18 mm width follow the ISO 15 diameter series, shared with the 61917 deep-groove envelope.
What is the contact angle of 71917?
The nominal contact angle is 40° (suffix C): a higher angle carries more axial load but limits speed. A 25° (suffix E or A5) variant runs faster and is preferred for high-speed spindles; a 15° (suffix C7) version exists for very-high-speed duty. Confirm the angle and ball complement in the supplier catalogue.
Can a single 71917 take axial load in both directions?
No. A single-row angular-contact bearing carries axial load in one direction only. For bidirectional thrust, mount a matched pair — DB (back-to-back) for a rigid, moment-resisting arrangement with preload class light (L) for speed or heavy (H) for stiffness, DF (face-to-face) for thermal expansion tolerance, or DT (tandem) to share one-direction load.
How fast can a 71917 run?
Thin-section angular-contact bearings reach high speeds because the 17.5 mm section keeps the ball set light, but the practical limit is set by the lubricant and the precision of the 85 mm seat rather than the geometry alone; a 25° (E/A5) contact-angle variant and a light (L) preload class run faster than a 40° heavy-preloaded pair. Confirm the limiting speed in the supplier catalogue.
Reviewed & verified by the MPN Base engineering desk against source catalog iso15-ed4-geometry on 2026-09-24. Read our editorial & correction policy.