QJ317 bearing: complete specifications & equivalents
The QJ317 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 | NTN |
| 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 | 218 kN |
| Basic static load rating C0 | 370 kN |
| Fatigue load limit Pu | 13.8 kN |
| Limiting speed (mechanical) | 3000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 5430 g |
| Manufacturer designation | NTN QJ317 |
| 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 & QJ300-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 QJ300-series | 17 mm |
| Largest outer diameter in QJ300-series | 400 mm |
| Width range across QJ300-series | 14–78 mm |
| Bore position in QJ300-series (smallest first) | 15 of 28 |
| Bore above smallest QJ300-series size | 68 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| QJ317 | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier. |
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 QJ317 model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, QJ317 appears as a heavy-duty QJ300 four-point family bearing of 85 mm bore, 180 mm outside diameter and 41 mm width. NTN builds the number from QJ3 is the four-point dimension series (heavy-duty QJ300 four-point family), then the last two digits 17 give the bore by the standard code table (85 mm); there is no suffix — the split inner ring and 35 deg contact angle are inherent to the QJ design. The 35 deg four-point geometry doubles the axial contact points, so the 218 kN rating is available for thrust in both directions. Against a deep-groove bearing of the same 85 mm bore, this bearing trades some pure-radial comfort for real one-direction thrust capacity and higher running accuracy. Shaft and housing shoulders must clear the ring corners yet support enough face — the catalogue abutment diameters for the 85 mm bore give the working limits.
Typical equipment & failure modes
Common applications
- crane and hoist gearbox shafts
- paper-machine roll and calendar drives
- extruder and mixer gearbox output shafts
- mining conveyor head-shaft positions
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
- resin-cage cracking on the 7900-series sizes after hot, dry running or solvent attack on the polymer
- current-erosion pitting on VFD-driven motor shafts, first visible as a grey frosted band across both raceways
- flaking that starts at the raceway shoulder on the thrust-loaded side when axial load repeatedly exceeds the design share
Selection pitfalls — read before you substitute
- Bearings of 85 mm bore arrive heavy enough that handling damage (dents from slings, tilting on the shaft) is a real failure precursor — use proper lifting and heating kit.
- The QJ split inner ring must be clamped by the shaft nut/shoulder on both halves — assembling it against a single small shoulder leaves one half-ring free to walk.
- If the application vibrates at standstill (transport, idle machine next to a running line), specify protection: the contact ellipse of a preloaded bearing false-brinells faster than a loose one.
- A QJ317 mounted the wrong way round still turns smoothly by hand; the failure shows up weeks later as raceway flaking on the unloaded-looking side.
- A QJ317 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 218/370 kN ratings and 13.8 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for QJ317; 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 QJ317?
QJ317 is a four-point contact ball bearing to ISO 15: 85 mm bore, 180 mm outside diameter, 41 mm width (3.346 x 7.087 x 1.614 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 218 kN, C0 370 kN and a 13.8 kN fatigue load limit Pu; the grease limiting speed is 3,000 r/min and the oil rating 4,000 r/min; mass about 5430 g.
How is the QJ317 designation structured?
QJ3 is the four-point dimension series (heavy-duty QJ300 four-point family); the last two digits 17 give the bore by the standard code table (85 mm); there is no suffix — the split inner ring and 35 deg contact angle are inherent to the QJ design. The 180 mm OD and 41 mm width follow the ISO 15 boundary-dimension plan for that series.
Which axial direction does QJ317 support?
QJ317 is a four-point contact bearing: the split inner ring lets each ball touch the raceways at two points, so one bearing locates the shaft in both axial directions at its 35 deg contact angle. It is normally mounted with slight radial clearance against the housing as the axial-locating member.
What lubrication speeds does NTN print for QJ317?
Per NTN Ball and Roller Bearings CAT.No.2203E, the grease limiting speed is 3,000 r/min and the oil rating 4,000 r/min. 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 QJ317?
The 85/180/41 mm envelope is ISO 15 interchangeable, but internal geometry — contact angle, osculation, cage and shoulder details — is maker-specific. Re-verify C 218 kN / C0 370 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.