7317-BECBY bearing: complete specifications & equivalents
The 7317-BECBY is a ISO 15 radial bearing sized 85 x 180 x 41 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 85 mm |
| Outer diameter D | 180 mm |
| Width B | 41 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 156 kN |
| Basic static load rating C0 | 132 kN |
| Fatigue load limit Pu | 4.9 kN |
| Reference speed (thermal) | 4500 rpm |
| Limiting speed (mechanical) | 4800 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 4450 g |
| Manufacturer designation | 7317 BECBY |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018) |
| Last verified | 2026-09-27 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018)) · extracted 2026-09-27
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 & 7300-series range
| Bore d | 3.346 in |
|---|---|
| Outer diameter D | 7.087 in |
| Width B | 1.614 in |
| ISO bore code | 17 |
| Radial section height (D−d)/2 | 47.5 mm |
| Smallest bore in 7300-series | 10 mm |
| Largest outer diameter in 7300-series | 420 mm |
| Width range across 7300-series | 11–80 mm |
| Bore position in 7300-series (smallest first) | 18 of 31 |
| Bore above smallest 7300-series size | 75 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 7317-BEP | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 85×180×41 mm envelope with catalogue ratings within 10 %; 7317 BEP is the glass-fibre PA66 cage, open arrangement execution of this size — boundary dimensions interchangeable, execution differs. |
| 7317-BEM | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 85×180×41 mm envelope with catalogue ratings within 10 %; 7317 BEM is the brass cage, open arrangement execution of this size — boundary dimensions interchangeable, execution differs. |
| 7317-BECBP | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 85×180×41 mm envelope with catalogue ratings within 10 %; 7317 BECBP is the glass-fibre PA66 cage, open arrangement execution of this size — boundary dimensions interchangeable, execution differs. |
| 7317-BEGAPH | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 85×180×41 mm envelope with catalogue ratings within 10 %; 7317 BEGAPH is the PEEK cage, open arrangement execution of this size — boundary dimensions interchangeable, execution differs. |
| 7317-BECBM | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 85×180×41 mm envelope with catalogue ratings within 10 %; 7317 BECBM is the brass cage, open arrangement execution of this size — boundary dimensions interchangeable, execution differs. |
| QJ-317-N2MA | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 85×180×41 mm envelope, but catalogue C/C0 differ between executions (156/132 kN vs 250/255 kN) — boundary dimensions match, not a load-rating equivalent. |
| 7317 | SKF | full Dimensions and internal design equivalent — standard interchange. | SKF SKF 7317 BEP is the basic 85×180×41 mm angular-contact page with ratings within 10 % of this execution — same boundary dimensions, verify execution details. |
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 7317-BECBY model number is decoded
7317 BECBY is SKF's 85 mm-bore single-row angular-contact ball bearing in the 7300 series, nominal 40° (B) contact angle, 85×180×41 mm to the ISO dimension plan. 40° contact angle (suffix B): the steep standard single-row angle, giving the highest axial capacity at the cost of speed, with a recommended load ratio Fa/Fr ≥ 1. E marks the optimized internal design with an enhanced ball complement and race geometry. stamped brass cage, ball-centred (suffix Y) — lighter than the machined M cage but brass rather than polymer. CB means universally matchable with Normal axial internal clearance: the two side faces are ground so any two units form DB (back-to-back), DF (face-to-face) or DT (tandem) sets without regrinding. BECBY combines the optimized 40° geometry with CB universal clearance and a stamped brass Y cage. Envelope 85×180×41 mm (3.346×7.087×1.614 in), 47.5 mm radial section height, C 156 kN, C0 132 kN, Pu 4.9 kN.reference speed 4,500 r/min (thermal) and limiting speed 4,800 r/min (mechanical), catalogue mass 4450 g. Speed planning distinguishes the two published ceilings mechanically: the cage and balls tolerate 4,800 r/min while thermal balance under catalogue load sets the 4,500 r/min reference; at dm ≈ 132.5 mm the corresponding dn is approximately 636k mm·r/min. Sizing arithmetic on the 85 mm bore: 156 kN C divided by the 47.5 mm radial section height gives 3.3 kN per section millimetre; the 4450 g mass and 3 % Pu/C share frame the light-load floor for the adjusted-life check. Speed-ratio note for this exact unit: the reference speed is 4,500 r/min against a 4,800 r/min limiting speed, i.e. a reference-to-limit ratio of 0.94. Cage detail specific to this order number: the Y cage is stamped from brass strip into ball pockets rather than machined from solid, giving a lighter cage assembly and lower centrifugal mass than the M execution; it remains brass (temperature and oil-additive tolerant, unlike PA66) but is the formed-cage design, and the machined-brass BECBM order number remains the choice for severe shock or marginal lubrication.
Typical equipment & failure modes
Common applications
- dryer-cylinder pinion shafts
- medium and large machine-tool spindles
- industrial gearboxes and speed reducers
Known failure patterns
- thermal preload runaway in a back-to-back pair when inner-ring heat cannot expand away
- false brinelling on idle paired sets exposed to machine vibration
- ball skidding when Fa/Fr stays below the 1,0 (40°) or 0,55 (25°) ratio and the contact ellipse is unloaded
- stamped brass cage pocket deformation after shock loading beyond the lighter formed cage capacity
- mounting score marks when the bearing is cocked over a burr or keyway
- edge loading from shaft deflection or housing misalignment
Selection pitfalls — read before you substitute
- Keep the load ratio in the SKF design range: Fa/Fr ≥ 1 for this angle; below it the balls unload the contact ellipse and skid, which is why the catalogue insists on a minimum axial load (Fam ≈ A·(n·dm/1000)²) at high speed.
- Keep the load ratio in the SKF design range: Fa/Fr ≥ 1 for this angle; below it the balls unload the contact ellipse and skid, which is why the catalogue insists on a minimum axial load (Fam ≈ A·(n·dm/1000)²) at high speed.
- Reference and limiting speeds are different ceilings: design to both, and remember preload and oil/air cooling move the real thermal limit far from the catalogue reference value.
- Keep the load ratio in the SKF design range: Fa/Fr ≥ 1 for this angle; below it the balls unload the contact ellipse and skid, which is why the catalogue insists on a minimum axial load (Fam ≈ A·(n·dm/1000)²) at high speed.
- The steep 40° angle of 7317-BECBY favours thrust-heavy combined loads; for a predominantly radial high-speed position the 25° ACCBM execution of the same size is the alternative order number.
- Universally matchable BECBY bearings arrive ready for set mounting, not preloaded sets: preload results from how the set is clamped, so follow the SKF stand-off-ring and nut-torque procedure.
Frequently asked questions
What are the dimensions and catalogue data of 7317-BECBY?
7317 BECBY measures 85 mm bore × 180 mm OD × 41 mm width (3.346 × 7.087 × 1.614 in), mass about 4450 g. SKF 17000 ratings: C 156 kN, C0 132 kN, Pu 4.9 kN, reference speed 4,500 r/min (thermal) and limiting speed 4,800 r/min (mechanical).
What does the BECBY suffix mean?
40° contact angle (suffix B): the steep standard single-row angle, giving the highest axial capacity at the cost of speed, with a recommended load ratio Fa/Fr ≥ 1. E marks the optimized internal design with an enhanced ball complement and race geometry. stamped brass cage, ball-centred (suffix Y) — lighter than the machined M cage but brass rather than polymer. CB means universally matchable with Normal axial internal clearance: the two side faces are ground so any two units form DB (back-to-back), DF (face-to-face) or DT (tandem) sets without regrinding. BECBY combines the optimized 40° geometry with CB universal clearance and a stamped brass Y cage.
What do the reference and limiting speeds mean for 7317-BECBY?
The 4,500 r/min reference (thermal) and 4,800 r/min limiting (mechanical) speeds are catalogue conditions; preload, lubrication and heat removal move the permissible value, so re-calculate for the actual arrangement.
Can one 7317-BECBY take thrust in both directions?
No. A single-row angular-contact bearing reacts axial load in one direction; reversing thrust needs a DB/DF matched pair (use a universally matchable CB/GA execution) or a double-row bearing. Under radial load the 40° angle induces an axial force that the arrangement must balance.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018) on 2026-09-27. Read our editorial & correction policy.