QJ214 bearing: complete specifications & equivalents
The QJ214 is a ISO 15 radial bearing sized 70 x 125 x 24 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 70 mm |
| Outer diameter D | 125 mm |
| Width B | 24 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 102 kN |
| Basic static load rating C0 | 168 kN |
| Fatigue load limit Pu | 7.15 kN |
| Limiting speed (mechanical) | 4000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1360 g |
| Manufacturer designation | NTN QJ214 |
| 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 & QJ200-series range
| Bore d | 2.756 in |
|---|---|
| Outer diameter D | 4.921 in |
| Width B | 0.945 in |
| ISO bore code | 14 |
| Radial section height (D−d)/2 | 27.5 mm |
| Smallest bore in QJ200-series | 15 mm |
| Largest outer diameter in QJ200-series | 360 mm |
| Width range across QJ200-series | 11–58 mm |
| Bore position in QJ200-series (smallest first) | 12 of 29 |
| Bore above smallest QJ200-series size | 55 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the QJ214 model number is decoded
The medium-duty QJ200 four-point family entry QJ214 carries a 70 mm bore in a 125 mm outside diameter, 24 mm wide envelope. Two fields make up the code — QJ2 is the four-point dimension series (medium-duty QJ200 four-point family) and the last two digits 14 give the bore by the standard code table (70 mm); there is no suffix — the split inner ring and 35 deg contact angle are inherent to the QJ design. Catalogue dynamic rating C is 102 kN against C0 168 kN — a C0/C ratio of 1.65 that is typical of an angular-contact contact ellipse. For a 70 mm shaft with combined load, the practical shortlist is this series, its neighbouring dimension series, and — where thrust reverses — a back-to-back pair rather than a single row. Set preload or end-play with the pair as a unit and lock the adjustment; a single angular-contact bearing cannot run free like a deep-groove one.
Typical equipment & failure modes
Common applications
- extruder and mixer gearbox output shafts
- mining conveyor head-shaft positions
- marine auxiliary and winch gearbox shafts
- rolling-mill and metalworking drive 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
- lubricant starvation scoring at the ball/raceway contact when grease volume or relubrication interval is guessed instead of calculated
- contamination-induced denting — hard particles rolled into the contact ellipse become the initiation points for surface fatigue
Selection pitfalls — read before you substitute
- Bearings of 70 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.
- On a 70 mm shaft, an interference fit eats internal clearance; skipping the clearance/preload recalculation is the classic cause of a new bearing running 20 deg C hotter than the drawing suggests.
- The C0 of 168 kN is a static rating, not a permissible running thrust — sizing continuous axial load from C0 alone is a recurring drawing-office error.
- Substituting the B (40 deg) execution for the standard 30 deg bearing changes the axial/radial load split — the shaft position and the mating bearing see different forces even though the envelope is identical.
- The 102/168 kN ratings and 7.15 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for QJ214; 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 QJ214?
QJ214 is a four-point contact ball bearing to ISO 15: 70 mm bore, 125 mm outside diameter, 24 mm width (2.756 x 4.921 x 0.945 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 102 kN, C0 168 kN and a 7.15 kN fatigue load limit Pu; the grease limiting speed is 4,000 r/min and the oil rating 5,400 r/min; mass about 1360 g.
How is the QJ214 designation structured?
QJ2 is the four-point dimension series (medium-duty QJ200 four-point family); the last two digits 14 give the bore by the standard code table (70 mm); there is no suffix — the split inner ring and 35 deg contact angle are inherent to the QJ design. The 125 mm OD and 24 mm width follow the ISO 15 boundary-dimension plan for that series.
Which axial direction does QJ214 support?
QJ214 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 QJ214?
Per NTN Ball and Roller Bearings CAT.No.2203E, the grease limiting speed is 4,000 r/min and the oil rating 5,400 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 QJ214?
The 70/125/24 mm envelope is ISO 15 interchangeable, but internal geometry — contact angle, osculation, cage and shoulder details — is maker-specific. Re-verify C 102 kN / C0 168 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.