31316 bearing: complete specifications & equivalents
The 31316 is a ISO 355 radial bearing sized 80 x 170 x 42.5 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 80 mm |
| Outer diameter D | 170 mm |
| Width B | 42.5 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 276 kN |
| Basic static load rating C0 | 265 kN |
| Fatigue load limit Pu | 30.5 kN |
| Reference speed (thermal) | 3000 rpm |
| Limiting speed (mechanical) | 4000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 4050 g |
| Manufacturer designation | SKF 31316 |
| Standard | ISO 355 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB |
| Last verified | 2026-09-26 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB) · extracted 2026-09-26
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric 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 & 31300-series range
| Bore d | 3.15 in |
|---|---|
| Outer diameter D | 6.693 in |
| Width B | 1.673 in |
| ISO bore code | 16 |
| Radial section height (D−d)/2 | 45 mm |
| Smallest bore in 31300-series | 25 mm |
| Largest outer diameter in 31300-series | 320 mm |
| Width range across 31300-series | 18.25–82 mm |
| Bore position in 31300-series (smallest first) | 12 of 22 |
| Bore above smallest 31300-series size | 55 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 31316 | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 355 boundary-dimension envelope; brand-specific OEM equivalents (NSK/FAG/NTN) pending multi-source data. |
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 31316 model number is decoded
In SKF catalogue PUB BU/P1 17000, 31316 appears as SKF 31316: an open, single-row tapered roller bearing in the steep-angle heavy section of the 31300 dimension series, supplied with a pressed-steel cage as standard.The code breaks down as type prefix 3 (tapered roller), series 13 (the steep-angle heavy section), and bore code 16 = 80 mm; dimensions 80×170×42.5 mm therefore match the ISO 355 envelope. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 45.0 mm radial section height ((170−80)/2) and 4050 g catalogue mass frame a 80 mm bore bearing rated at 276 kN C — roughly 3.45 kN of dynamic capacity per millimetre of bore before application factors. Because the contact line is tapered, one 31316 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 80 mm shaft typically takes a k5 seat with an H7 housing bore.
Typical equipment & failure modes
Common applications
- rolling-mill auxiliary drives
- crane sheave and hoist gearboxes
- paper-machine and printing rolls
- construction machinery drives
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
- thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting
- uneven load sharing in a pair when spacer faces are not parallel to the bore
- pressed-steel cage wear or fracture after prolonged running above the limiting speed
- hard-particle indentation of the tapered raceway in unfiltered oil
Selection pitfalls — read before you substitute
- Mount the 80 mm bore 31316 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 313 series at 80 mm bore (170×42.5 mm) has a steeper contact angle than the 302/303 families — higher axial capacity per radial load but more induced thrust and heat; do not interchange with a 30316 without re-running the pair calculation.
- When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 31316 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.
- The tapered contact angle creates an induced axial load under pure radial force; include it in the 31316 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.
- The 4050 g mass and 42.5 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 31316.
- The 276/265 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 31316 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 31316 designation when purchasing and match the execution to the mounting arrangement.
Frequently asked questions
What are the dimensions and catalogue data of 31316?
The SKF 31316 is a single-row tapered roller bearing with 80 mm bore, 170 mm outer diameter and 42.5 mm width (3.15 × 6.693 × 1.673 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 276 kN, C0 265 kN, fatigue load limit Pu 30.5 kN, reference speed 3,000 r/min, limiting speed 4,000 r/min, mass about 4050 g. It is an open, separable bearing with a pressed-steel cage.
How does the 31316 bore code work?
The last two digits of 31316 are bore code 16, so 16 × 5 = 80 mm bore. The 170 mm OD and 42.5 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code.
What do the 31316 series and basic execution designations mean?
The leading 3 marks a single-row tapered roller bearing; the second digit 13 is the ISO 355 series (steep-angle heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution.
Can a single 31316 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 31316 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 31316 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB on 2026-09-26. Read our editorial & correction policy.