7236 bearing: complete specifications & equivalents
The 7236 is a ISO 15 radial bearing sized 180 x 320 x 52 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 180 mm |
| Outer diameter D | 320 mm |
| Width B | 52 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 340 kN |
| Basic static load rating C0 | 385 kN |
| Fatigue load limit Pu | 18.6 kN |
| Limiting speed (mechanical) | 2100 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 17700 g |
| Manufacturer designation | NTN 7236 |
| 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 | 7.087 in |
|---|---|
| Outer diameter D | 12.598 in |
| Width B | 2.047 in |
| ISO bore code | 36 |
| Radial section height (D−d)/2 | 70 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) | 30 of 36 |
| Bore above smallest 7200-series size | 170 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the 7236 model number is decoded
7236 is the 180 mm bore member of NTN's medium-duty 7200 single-row family, with a 320 mm outside diameter and 52 mm section width. NTN builds the number from 72 is the single-row dimension series (medium-duty 7200 single-row family), then 36 encodes the 180 mm bore (bore code x 5); with no letter after the digits it is the standard 30 deg contact-angle execution — the 40 deg version carries a B. Because the contact line is angled, one bearing of this type takes radial load plus thrust from one direction only — the opposite direction needs a second bearing or a matched set. For a 180 mm shaft with combined load, the practical shortlist is this series, its 7300-series heavier section, and — where thrust reverses — a back-to-back pair rather than a single row. A 180 mm shaft typically takes a m6/n6 fit for rotating inner-ring load; keep the housing bore to G6/H6 class so the contact geometry is not distorted.
Typical equipment & failure modes
Common applications
- steel-plant conveyor and table roll drives
- wind-turbine and heavy-machinery auxiliaries
- heavy industrial gearbox main shafts
- large fan, blower and turbo-compressor rotors
Known failure patterns
- impact brinelling dents on the 30 deg contact path after a shaft-side hammer blow during mounting, because axial shock travels straight through the contact angle
- 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
- flaking that starts at the raceway shoulder on the thrust-loaded side when axial load repeatedly exceeds the design share
- 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
- At this size the shaft fit, shoulder geometry and preload procedure dominate the outcome; a 180 mm bore bearing forgives nothing in a poorly machined housing.
- The standard 30 deg bearing and its B (40 deg) sibling share the envelope; picking between them is a load-direction decision, not a quality upgrade.
- 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 2,100 r/min speed figure assumes the catalogue lubrication state and a correctly set pair; real limits drop fast with excess grease fill or heavy preload.
- The 2,100 r/min speed figure assumes the catalogue lubrication state and a correctly set pair; real limits drop fast with excess grease fill or heavy preload.
- The 340/385 kN ratings and 18.6 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 7236; 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 7236?
7236 is a single-row angular contact ball bearing to ISO 15: 180 mm bore, 320 mm outside diameter, 52 mm width (7.087 x 12.598 x 2.047 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 340 kN, C0 385 kN and a 18.6 kN fatigue load limit Pu; the grease limiting speed is 2,100 r/min and the oil rating 2,800 r/min; mass about 17700 g.
How is the 7236 designation structured?
72 is the single-row dimension series (medium-duty 7200 single-row family); 36 encodes the 180 mm bore (bore code x 5); with no letter after the digits it is the standard 30 deg contact-angle execution — the 40 deg version carries a B. The 320 mm OD and 52 mm width follow the ISO 15 boundary-dimension plan for that series.
Which axial direction does 7236 support?
One 7236 alone takes thrust in one direction only, along its 30 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 7236?
Per NTN Ball and Roller Bearings CAT.No.2203E, the grease limiting speed is 2,100 r/min and the oil rating 2,800 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 7236?
The 180/320/52 mm envelope is ISO 15 interchangeable, but internal geometry — contact angle, osculation, cage and shoulder details — is maker-specific. Re-verify C 340 kN / C0 385 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.