6386-K-6320 bearing: complete specifications & equivalents
The 6386-K-6320 is a ISO 355 radial bearing sized 65.088 x 135.755 x 53.975 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 65.088 mm |
| Outer diameter D | 135.755 mm |
| Width B | 53.975 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 353 kN |
| Basic static load rating C0 | 400 kN |
| Fatigue load limit Pu | 45.5 kN |
| Reference speed (thermal) | 4000 rpm |
| Limiting speed (mechanical) | 5000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 3650 g |
| Manufacturer designation | SKF 6386/K-6320 |
| Standard | ISO 355 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB |
| Last verified | 2026-09-28 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB) · extracted 2026-09-28
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB); 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 & 6300-series range
| Bore d | 2.563 in |
|---|---|
| Outer diameter D | 5.345 in |
| Width B | 2.125 in |
| ISO bore code | 86 |
| Radial section height (D−d)/2 | 35.3 mm |
| Smallest bore in 6300-series | 59.987 mm |
| Largest outer diameter in 6300-series | 135.755 mm |
| Width range across 6300-series | 53.975–53.975 mm |
| Bore position in 6300-series (smallest first) | 2 of 2 |
| Bore above smallest 6300-series size | 5.100999999999992 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 6386-6320 | NTN | verify Commonly quoted cross reference; confirm against the target catalog before ordering. | Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue. |
| 6386-K-6320 | Timken | full Dimensions and internal design equivalent — standard interchange. | Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ. |
Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.
How the 6386-K-6320 model number is decoded
Speed planning uses two different ceilings: 4,000 r/min thermal reference and 5,000 r/min mechanical limiting speed. For a 65.088 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 6386 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Load system: the 353 kN basic dynamic rating C and 400 kN static rating C0 give a C0/C balance of 1.13, and dividing C by the 65.088 mm bore yields 5.42 kN per millimetre of journal — a density metric that compares across families; the 45.5 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 65.088 mm shaft carrying variable duty. The cup reference K-6320 is structural, not a suffix: it identifies the outer ring that, combined with the 6386 cone, produces the 65.088/135.755/53.975 mm envelope catalogue-listed as 6386. Quote the cup number in full when ordering — the 6300-series tables contain other cups that fit the same cone but change the bearing.Ordering number SKF 6386/K-6320 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 65.088 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.On the SKF nameplate, 6386 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 6300-series marking the dimensional series. In SKF suffix language a bare 6386 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately.
Typical equipment & failure modes
Common applications
- construction machinery drives
- marine deck machinery shafts
- heavy industrial gearboxes and speed reducers
- paper-machine and printing rolls
Known failure patterns
- cup or cone misalignment when the separable rings are not seated square during mounting
- loose cup rotation in the housing when the specified press fit is not achieved
- axial overload spalling at the roller-rib contact beyond the single-row thrust rating
- preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways
- pressed-steel cage wear or fracture after prolonged running above the limiting speed
- electrical pitting on VFD-driven shafts without grounding protection
Selection pitfalls — read before you substitute
- Mount the 65.088 mm bore 6386 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.
- The 6300-series inch series at 65.088 mm bore (135.755×53.975 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.
- A single 6386 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.
- O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 6386 mounting error.
- Open 6386 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.
- The 353/400 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.
- SKF lists several executions of 6386 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 6386/K-6320 designation when purchasing and match the execution to the mounting arrangement.
Frequently asked questions
Can a single 6386 take axial load in both directions?
No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared.
How does 6386 compare with a ball bearing of the same bore?
A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 6386 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting.
What shaft and housing fits suit 6386?
For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 53.975 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone.
Is 6386 interchangeable with other brands?
Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing.
What are the dimensions and catalogue data of 6386?
The SKF 6386/K-6320 is a single-row tapered roller bearing with 65.088 mm bore, 135.755 mm outer diameter and 53.975 mm width (2.563 × 5.345 × 2.125 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 353 kN, C0 400 kN, fatigue load limit Pu 45.5 kN, reference speed 4,000 r/min, limiting speed 5,000 r/min, mass about 3650 g. It is an open, separable bearing with a pressed-steel cage.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB on 2026-09-28. Read our editorial & correction policy.