7217B bearing: complete specifications & equivalents
The 7217B is a ISO 15 radial bearing sized 85 x 150 x 28 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 | 150 mm |
| Width B | 28 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 99.5 kN |
| Basic static load rating C0 | 80.5 kN |
| Fatigue load limit Pu | 5.45 kN |
| Limiting speed (mechanical) | 4000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1820 g |
| Manufacturer designation | NTN 7217B |
| 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 & 7200-series range
| Bore d | 3.346 in |
|---|---|
| Outer diameter D | 5.906 in |
| Width B | 1.102 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 32.5 mm |
| Smallest bore in 7200-series | 10 mm |
| Largest outer diameter in 7200-series | 540 mm |
| Width range across 7200-series | 9–85 mm |
| Bore position in 7200-series (smallest first) | 18 of 36 |
| Bore above smallest 7200-series size | 75 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the 7217B model number is decoded
7217B is the 85 mm bore member of NTN's medium-duty 7200 single-row family, with a 150 mm outside diameter and 28 mm section width. NTN builds the number from 72 is the single-row dimension series (medium-duty 7200 single-row family), then 17 encodes the 85 mm bore (bore code x 5), and the trailing B marks the 40 deg contact-angle execution (the no-letter standard bearing works at 30 deg). Catalogue dynamic rating C is 99.5 kN against C0 80.5 kN — a C0/C ratio of 0.81 that is typical of an angular-contact contact ellipse. If the duty is mainly high speed with modest thrust, the 7900-series cross-section is the lighter alternative; if thrust dominates, the 7300-series section carries more. Heat-mounting to 80-90 deg C is the clean route onto a 85 mm shaft; drive-fits through the balls transmit force through the contact ellipse and can brinell it.
Typical equipment & failure modes
Common applications
- large pump, fan and compressor rotor shafts
- crane and hoist gearbox shafts
- paper-machine roll and calendar drives
- extruder and mixer gearbox output 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
- thermal runaway from excessive preload: the pair runs hot, grease darkens and the contact ellipse spreads until the raceways smear
- machined-cage land scoring when a high-speed spindle runs past its grease rating and the cage runs dry on its guidance surface
- edge loading and early spalling from housing bores that are out of round or shoulders that are too small for the ring face
- 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 40 deg B-execution raises axial capacity but lowers the speed ceiling — do not copy the standard-bearing speed and preload settings onto it.
- Do not pair two random 7217B 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.
- A single-row angular contact left loose on the shaft to "help assembly" will fret the seat: the contact angle keeps driving the ring axially under load.
- 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 99.5/80.5 kN ratings and 5.45 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 7217B; 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 7217B?
7217B is a single-row angular contact ball bearing to ISO 15: 85 mm bore, 150 mm outside diameter, 28 mm width (3.346 x 5.906 x 1.102 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 99.5 kN, C0 80.5 kN and a 5.45 kN fatigue load limit Pu; the grease limiting speed is 4,000 r/min and the oil rating 5,300 r/min; mass about 1820 g.
How is the 7217B designation structured?
72 is the single-row dimension series (medium-duty 7200 single-row family); 17 encodes the 85 mm bore (bore code x 5), and the trailing B marks the 40 deg contact-angle execution (the no-letter standard bearing works at 30 deg). The 150 mm OD and 28 mm width follow the ISO 15 boundary-dimension plan for that series.
Which axial direction does 7217B support?
One 7217B alone takes thrust in one direction only, along its 40 deg contact angle; reversing thrust calls for a second bearing or a factory-matched DB/DF/DT pair (the catalogue right-hand columns list the paired ratings). Radial load is always carried as a combined load through the angled contact.
What lubrication speeds does NTN print for 7217B?
Per NTN Ball and Roller Bearings CAT.No.2203E, the grease limiting speed is 4,000 r/min and the oil rating 5,300 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 7217B?
The 85/150/28 mm envelope is ISO 15 interchangeable, but internal geometry — contact angle, osculation, cage and shoulder details — is maker-specific. Re-verify C 99.5 kN / C0 80.5 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.