618-1320-MA bearing: complete specifications & equivalents
The 618-1320-MA is a ISO 15 radial bearing sized 1320 x 1600 x 122 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 1320 mm |
| Outer diameter D | 1600 mm |
| Width B | 122 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 956 kN |
| Basic static load rating C0 | 3150 kN |
| Fatigue load limit Pu | 35.5 kN |
| Reference speed (thermal) | 480 rpm |
| Limiting speed (mechanical) | 400 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 500000 g |
| Manufacturer designation | 618/1320 MA |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018) |
| Last verified | 2026-09-27 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018)) · extracted 2026-09-27
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018)); SKF® and SKF Explorer® are trademarks of AB SKF, used here for identification only — mpnbase is not an authorized SKF distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at skf.com.
Dimensions in inches & 61800-series range
| Bore d | 51.969 in |
|---|---|
| Outer diameter D | 62.992 in |
| Width B | 4.803 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 140 mm |
| Smallest bore in 61800-series | 1 mm |
| Largest outer diameter in 61800-series | 1820 mm |
| Width range across 61800-series | 1–140 mm |
| Bore position in 61800-series (smallest first) | 73 of 74 |
| Bore above smallest 61800-series size | 1319 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the 618-1320-MA model number is decoded
In the large-bore 61800-series, the bore is written directly after the slash as 1320 mm (large thin-section bores use the slash spelling instead of the two-digit code). The envelope is 1320×1600×122 mm (51.969×62.992×4.803 in) with a 140.0 mm radial section height, C 956 kN, C0 3150 kN and Pu 35.5 kN. The open 618/1320 MA carries no shields or seals and relies on application lubrication and external sealing. The MA suffix identifies the machined brass cage execution, a separate order number from the pressed-steel version. Limiting speed 400 r/min, catalogue mass 500000 g. A thin section saves space but leaves little margin for misalignment or shaft deflection.
Typical equipment & failure modes
Common applications
- crusher auxiliary drives
- space-constrained gearboxes
- clutch and transmission assemblies
- robotics and automation joints
Known failure patterns
- contamination wear when the open arrangement is used without external seals
- lubricant starvation where no regreasing interval is maintained
- rolling-contact fatigue spalling once the catalogue L10 life is exceeded
- brinelling from static overload or hammer blows during mounting
Selection pitfalls — read before you substitute
- Assign interference to the rotating ring: on a conventional shaft-mounted 1320 mm position the inner ring rotates, so use a k5/m6 shaft seat with an H7 housing — reverse the logic if the outer ring rotates.
- Fillet radii must clear the 618-1320-MA chamfer so the 122 mm-wide ring seats square; an oversized shaft radius creates point contact on the ring face.
- The MA suffix on 618-1320-MA denotes a machined brass cage: it is the choice for high speeds, marginal lubrication and shock/vibration duty, and it is temperature-tolerant where polymer cages are not — the 500000 g quoted mass includes the heavier cage.
- Open 618-1320-MA needs external sealing at the arrangement level; in dusty housings its life depends entirely on those external seals and the regreasing schedule.
- Plan a relubrication interval for 618-1320-MA; run-to-failure on open deep-groove bearings is the dominant early-failure cause.
- Assign interference to the rotating ring: on a conventional shaft-mounted 1320 mm position the inner ring rotates, so use a k5/m6 shaft seat with an H7 housing — reverse the logic if the outer ring rotates.
Frequently asked questions
What are the dimensions of 618-1320-MA?
The SKF 618/1320 MA measures 1320 mm bore × 1600 mm OD × 122 mm width (51.969 × 62.992 × 4.803 in), mass about 500000 g. It is open, with no shields or seals.
Why is there a slash in the designation 618/1320 MA?
The slash writes a bore that falls outside the two-digit code table: 618/1320 means 1320 mm bore. The site slug 618-1320-MA replaces the slash with a hyphen.
What is the difference between 618-1320-MA and a same-bore 62-series bearing?
Section height differs: 618-1320-MA has a 140 mm radial section and C 956 kN; always match d, D and B — same bore alone never makes two bearings interchangeable.
Which fits should I use for 618-1320-MA?
With a rotating inner ring use roughly m6 on the shaft and H7 in the 1600 mm housing; reverse the interference if the outer ring rotates.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018) on 2026-09-27. Read our editorial & correction policy.