QJ212 bearing: complete specifications & equivalents
The QJ212 is a ISO 15 radial bearing sized 60 x 110 x 22 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 60 mm |
| Outer diameter D | 110 mm |
| Width B | 22 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 86 kN |
| Basic static load rating C0 | 138 kN |
| Fatigue load limit Pu | 5.9 kN |
| Limiting speed (mechanical) | 4700 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 980 g |
| Manufacturer designation | NTN QJ212 |
| 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 | 2.362 in |
|---|---|
| Outer diameter D | 4.331 in |
| Width B | 0.866 in |
| ISO bore code | 12 |
| Radial section height (D−d)/2 | 25 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) | 10 of 29 |
| Bore above smallest QJ200-series size | 45 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the QJ212 model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, QJ212 appears as a medium-duty QJ200 four-point family bearing of 60 mm bore, 110 mm outside diameter and 22 mm width. The designation breaks down as QJ2 is the four-point dimension series (medium-duty QJ200 four-point family); the last two digits 12 give the bore by the standard code table (60 mm); there is no suffix — the split inner ring and 35 deg contact angle are inherent to the QJ design. The static margin, C0 138 kN versus C 86 kN, is what supports slow oscillating duty and shock without immediate brinelling. Size selection is usually finished by checking that the C0 of 138 kN covers the maximum static or shock condition with the catalogue safety factor, not only the running load. Mount with the thrust against the marked face: the contact angle runs from the low shoulder of the inner ring to the high shoulder of the outer ring, and reversing it throws the capacity away.
Typical equipment & failure modes
Common applications
- rolling-mill and metalworking drive shafts
- large pump, fan and compressor rotor shafts
- crane and hoist gearbox shafts
- paper-machine roll and calendar drives
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
- flaking that starts at the raceway shoulder on the thrust-loaded side when axial load repeatedly exceeds the design share
- lubricant starvation scoring at the ball/raceway contact when grease volume or relubrication interval is guessed instead of calculated
Selection pitfalls — read before you substitute
- Bearings of 60 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.
- Do not pair two random QJ212 bearings from stock and expect catalogue paired ratings — matched-set grinding is what makes DB/DF/DT preload behave, and NTN sells those as separate order numbers.
- Never use a four-point or double-row bearing as a like-for-like swap for a single QJ212 without re-checking axial float, heat and housing width — the kinematics differ.
- Do not pair two random QJ212 bearings from stock and expect catalogue paired ratings — matched-set grinding is what makes DB/DF/DT preload behave, and NTN sells those as separate order numbers.
- The 86/138 kN ratings and 5.9 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for QJ212; 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 QJ212?
QJ212 is a four-point contact ball bearing to ISO 15: 60 mm bore, 110 mm outside diameter, 22 mm width (2.362 x 4.331 x 0.866 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 86 kN, C0 138 kN and a 5.9 kN fatigue load limit Pu; the grease limiting speed is 4,700 r/min and the oil rating 6,300 r/min; mass about 980 g.
How is the QJ212 designation structured?
QJ2 is the four-point dimension series (medium-duty QJ200 four-point family); the last two digits 12 give the bore by the standard code table (60 mm); there is no suffix — the split inner ring and 35 deg contact angle are inherent to the QJ design. The 110 mm OD and 22 mm width follow the ISO 15 boundary-dimension plan for that series.
Which axial direction does QJ212 support?
QJ212 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 QJ212?
Per NTN Ball and Roller Bearings CAT.No.2203E, the grease limiting speed is 4,700 r/min and the oil rating 6,300 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 QJ212?
The 60/110/22 mm envelope is ISO 15 interchangeable, but internal geometry — contact angle, osculation, cage and shoulder details — is maker-specific. Re-verify C 86 kN / C0 138 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.