31318 bearing dimensions & suffix variants
Look up recorded dimensions for designations beginning with 31318. The table retains complete manufacturer designations so special suffixes and different dimensional variants remain visible.
On this page5 sections ⌄
Find by measured dimensions
Enter bore d, outside diameter D and width B. Use decimals or inch fractions such as 1/2 or 1 1/4.
31318 dimensions and recorded technical data
Use the named dimensions for each complete record below. A generic d×D×B answer is not asserted where the base record is missing, dimension symbols are unverified, or the product uses a different geometry such as a housing or thrust assembly. Suffix records are not substituted for a missing base specification.
The numeric series boundary is preserved: a longer number is not included merely because its first digits match. 16 recorded variants are listed. A dash means the value is missing, not zero.
Catalogue parameters for 31318
Choose the complete brand and marking before reading a value. These source-labelled records add dimensions, construction and engineering properties where they were recorded; a shared model number does not establish interchangeability.
Units, ranges and minimum/maximum qualifiers are retained. The data is a dated catalogue reference, not a certified drawing, a complete current specification or an operating approval.
FAG 31318 — 64 recorded parameters
Tapered roller bearing
Reference: Schaeffler medias — FAG; source snapshot 2026-09-02.
Keep total assembly width distinct from inner- and outer-ring widths. The same nominal bore does not establish a matching cup/cone set.
Values shown are retained from the recorded source. Zero boundary dimensions and zero load ratings from incomplete legacy feeds are withheld rather than presented as usable specifications.
Main Dimensions & Performance Data
| Parameter | Source symbol | Recorded value |
|---|---|---|
| Bore diameter | d | 90 mm |
| Bore diameter | d | 3.543 in |
| Outside diameter | D | 190 mm |
| Outside diameter | D | 7.48 in |
| Width, inner ring | B | 43 mm |
| Width, inner ring | B | 1.693 in |
| Width, outer ring | C | 30 mm |
| Width, outer ring | C | 1.181 in |
| Width, total | T | 46.5 mm |
| Width, total | T | 1.831 in |
| Basic dynamic load rating, radial | Cr | 275,000 N |
| Basic dynamic load rating, radial | Cr | 61,825.54 lbf |
| Basic static load rating, radial | C0r | 325,000 N |
| Basic static load rating, radial | C0r | 73,066.547 lbf |
| Fatigue load limit, radial | Cur | 35,500 N |
| Fatigue load limit, radial | Cur | 7,981.115 lbf |
| Limiting speed | nG | 3,700 1/min |
| Thermal speed rating | nϑr | 2,900 1/min |
| Mass | ≈m | 5.386 kg |
| Mass | ≈m | 11.874 lbs |
Mounting dimensions
| Parameter | Source symbol | Recorded value |
|---|---|---|
| Maximum diameter of shaft shoulder | da max | 109 mm |
| Maximum diameter of shaft shoulder | da max | 4.291 in |
| Minimum diameter of shaft shoulder | db min | 104 mm |
| Minimum diameter of shaft shoulder | db min | 4.094 in |
| Minimum diameter of housing shoulder | Da min | 151 mm |
| Minimum diameter of housing shoulder | Da min | 5.945 in |
| Maximum diameter of housing shoulder | Da max | 176 mm |
| Maximum diameter of housing shoulder | Da max | 6.929 in |
| Minimum diameter of housing shoulder | Db min | 179 mm |
| Minimum diameter of housing shoulder | Db min | 7.047 in |
| Minimum axial space | Ca min | 6 mm |
| Minimum axial space | Ca min | 0.236 in |
| Minimum axial space | Cb min | 16.5 mm |
| Minimum axial space | Cb min | 0.65 in |
| Maximum fillet radius of shaft | ra max | 4 mm |
| Maximum fillet radius of shaft | ra max | 0.157 in |
| Maximum fillet radius of housing | rb max | 3 mm |
| Maximum fillet radius of housing | rb max | 0.118 in |
Dimensions
| Parameter | Source symbol | Recorded value |
|---|---|---|
| Minimum chamfer dimension of inner ring back face | r1, 2 min | 4 mm |
| Minimum chamfer dimension of inner ring back face | r1, 2 min | 0.157 in |
| Minimum chamfer dimension of outer ring back face | r3, 4 min | 3 mm |
| Minimum chamfer dimension of outer ring back face | r3, 4 min | 0.118 in |
| Distance between the apexes of the pressure cones | a | 58 mm |
| Distance between the apexes of the pressure cones | a | 2.283 in |
| Guidance rib diameter of inner ring | d1 | 138.9 mm |
| Guidance rib diameter of inner ring | d1 | 5.469 in |
Temperature range
| Parameter | Source symbol | Recorded value |
|---|---|---|
| Operating temperature min. | Tmin | -30 °C |
| Operating temperature min. | Tmin | -22 °F |
| Operating temperature max. | Tmax | 120 °C |
| Operating temperature max. | Tmax | 248 °F |
Calculation factors
| Parameter | Source symbol | Recorded value |
|---|---|---|
| Limiting value of Fa/Fr for the applicability of diff. Values of factors X and Y | e | 0.83 |
| Dynamic axial load factor | Y | 0.73 |
| Static axial load factor | Y0 | 0.4 |
Product characteristics
| Parameter | Source symbol | Recorded value |
|---|---|---|
| Tolerance class | PN | Normal (ISO 492:2023) |
| Heat treatment | Not separately recorded | Standard |
| Cage | Standard | Sheet steel cage, window cage, roller-guided |
| Internal design | Not separately recorded | Standard |
| Quality level | Not separately recorded | Standard |
| Number of rows | 1 | Single-row design |
Capabilities & suitability
| Parameter | Source symbol | Recorded value |
|---|---|---|
| Radial load capacity | Not separately recorded | Yes |
| Axial load capacity in one direction | Not separately recorded | Yes |
| Suitable for grease lubrication | Not separately recorded | Yes |
| Suitable for oil lubrication | Not separately recorded | Yes |
| Unsealed design | Not separately recorded | Yes |
SKF 31318 — 50 recorded parameters
Single row tapered roller bearing
Reference: SKF product catalogue; source snapshot 2026-09-02.
Keep total assembly width distinct from inner- and outer-ring widths. The same nominal bore does not establish a matching cup/cone set.
Values shown are retained from the recorded source. Zero boundary dimensions and zero load ratings from incomplete legacy feeds are withheld rather than presented as usable specifications.
Dimensions
| Parameter | Source symbol | Recorded value |
|---|---|---|
| Bore diameter | Not separately recorded | 90.0 mm |
| Outside diameter | Not separately recorded | 190.0 mm |
| Width, total | Not separately recorded | 46.5 mm |
| Width, inner ring | Not separately recorded | 43.0 mm |
| Width, outer ring | Not separately recorded | 30.0 mm |
| Contact angle | Not separately recorded | 28.8 ° |
Performance
| Parameter | Source symbol | Recorded value |
|---|---|---|
| Basic dynamic load rating | Not separately recorded | 283.0 kN |
| Basic static load rating | Not separately recorded | 315.0 kN |
| Reference speed | Not separately recorded | 2400.0 r/min |
| Limiting speed | Not separately recorded | 3400.0 r/min |
Properties
| Parameter | Source symbol | Recorded value |
|---|---|---|
| Bearing part | Not separately recorded | Complete bearing |
| Number of rows | Not separately recorded | 1 |
| Locating feature, bearing outer ring | Not separately recorded | Without |
| Bore type | Not separately recorded | Cylindrical |
| Cage | Not separately recorded | Sheet metal |
| Arrangement of contact angle (double-row bearing) | Not separately recorded | Not applicable |
| Matched arrangement | Not separately recorded | No |
| Coating | Not separately recorded | Without |
| Sealing | Not separately recorded | Without |
| Relubrication feature | Not separately recorded | Without |
| Unit system | Not separately recorded | Metric |
| Indicative carbon footprint for new product | Not separately recorded | 19.6 kg CO 2 e |
Logistics
| Parameter | Source symbol | Recorded value |
|---|---|---|
| Product net weight | Not separately recorded | 5.29 kg |
Engineering — Engineering specifications
| Parameter | Source symbol | Recorded value |
|---|---|---|
| Dimension series | Not separately recorded | 7GB |
Engineering — Dimensions
| Parameter | Source symbol | Recorded value |
|---|---|---|
| Bore diameter | d | 90 mm |
| Outside diameter | D | 190 mm |
| Bearing width, total | T | 46.5 mm |
| Shoulder diameter of inner ring | d 1 | ≈ 138.88 mm |
| Width of inner ring | B | 43 mm |
| Width of outer ring | C | 30 mm |
| Chamfer dimension of inner ring | r 1,2 | min. 4 mm |
| Chamfer dimension of outer ring | r 3,4 | min. 3 mm |
| Distance side face to pressure point | a | 57.3 mm |
Engineering — Abutment dimensions
| Parameter | Source symbol | Recorded value |
|---|---|---|
| Diameter of shaft abutment | d a | max. 110 mm |
| Diameter of shaft abutment | d b | min. 105.5 mm |
| Diameter of housing abutment | D a | min. 151 mm |
| Diameter of housing abutment | D a | max. 177.5 mm |
| Diameter of housing abutment | D b | min. 179 mm |
| Minimum width of space required in housing on large side face | C a | min. 5 mm |
| Minimum width of space required in housing on small side face | C b | min. 16.5 mm |
| Radius of shaft fillet | r a | max. 4 mm |
| Radius of housing fillet | r b | max. 3 mm |
Engineering — Calculation data
| Parameter | Source symbol | Recorded value |
|---|---|---|
| Basic dynamic load rating | C | 283 kN |
| Basic static load rating | C 0 | 315 kN |
| Fatigue load limit | P u | 35.5 kN |
| Reference speed | Not separately recorded | 2400 r/min |
| Limiting speed | Not separately recorded | 3400 r/min |
| Limiting value | e | 0.83 |
| Calculation factor | Y | 0.72 |
| Calculation factor | Y 0 | 0.4 |
No recorded variant matches these filters. Clear a filter to see other records; no substitute has been inferred.
| Brand / full designation | Named dimensions (mm / in) | Dynamic C (kN) | Static C0 (kN) | Reference speed (rpm) | Limiting speed (rpm) | Mass (kg / g) |
|---|---|---|---|---|---|---|
| SKF31318Single row tapered roller bearing |
| 283 kN | 315 kN | 2400 rpm | 3400 rpm | 5.29 kg5290 g |
| FAG31318Tapered roller bearing |
| 275 kN | 325 kN | 2900 rpm | 3700 rpm | 5.386 kg5386 g |
| TIMKEN31318Tapered roller bearing |
| 384 kN | 421 kN | — | — | 5.92 kg5920 g |
| SKF31318/DFMatched tapered roller bearings arranged face-to-face |
| 486 kN | 630 kN | 1900 rpm | 3400 rpm | 11.4 kg11400 g |
| SKF31318/DFC185Matched tapered roller bearings arranged face-to-face |
| 486 kN | 630 kN | 1900 rpm | 3400 rpm | 11.4 kg11400 g |
| SKF31318/DFC70Matched tapered roller bearings arranged face-to-face |
| 486 kN | 630 kN | 1900 rpm | 3400 rpm | 11.4 kg11400 g |
| SKF31318T103/DB31Matched tapered roller bearings arranged back-to-back |
| 486 kN | 630 kN | 1900 rpm | 3400 rpm | 11.8 kg11800 g |
| FAG31318>ATapered roller bearing |
| 275 kN | 325 kN | 2900 rpm | 3700 rpm | 5.4 kg5400 g |
| FAG31318-HTapered roller bearing |
| 261 kN | 325 kN | 2900 rpm | 2960 rpm | 5.4 kg5400 g |
| FAG31318-P5Tapered roller bearing |
| 285 kN | 325 kN | 2900 rpm | 3700 rpm | 5.4 kg5400 g |
| FAG31318-P5>ATapered roller bearing |
| 285 kN | 325 kN | 2900 rpm | 3700 rpm | 5.4 kg5400 g |
| FAG31318-XLTapered roller bearing |
| 340 kN | 325 kN | 2900 rpm | 4450 rpm | 5.355 kg5355 g |
| FAG31318-XL>ATapered roller bearing |
| 340 kN | 325 kN | 2900 rpm | 4450 rpm | 5.5 kg5500 g |
| FAG31318-XL-DF-A0-35Tapered roller bearing set |
| 580 kN | 650 kN | 2550 rpm | 4450 rpm | 11.7 kg11700 g |
| FAG31318-XL-P5Tapered roller bearing |
| 340 kN | 325 kN | 2900 rpm | 4450 rpm | 5.5 kg5500 g |
| FAG31318-XL-P5>ATapered roller bearing |
| 340 kN | 325 kN | 2900 rpm | 4450 rpm | 5.5 kg5500 g |
Compare recorded seals, clearance, precision and materials
Manufacturer wording is retained. A missing property is not inferred from another brand or a similar suffix.
| Brand / designation | Closure | Original precision | Clearance | Cage | Material | Lubricant |
|---|---|---|---|---|---|---|
| SKF 31318 | Without | Not recorded | Not recorded | Sheet metal | Not recorded | None |
| FAG 31318 | Not recorded | PN — Normal (ISO 492:2023) | Not recorded | Standard — Sheet steel cage, window cage, roller-guided | Not recorded | Not recorded |
| TIMKEN 31318 | Open | ABMA Class K | Not recorded | Steel cage | Not recorded | Not recorded |
| SKF 31318/DF | Without | Not recorded | Not recorded | Sheet metal | Not recorded | None |
| SKF 31318/DFC185 | Without | Not recorded | Not recorded | Sheet metal | Not recorded | None |
| SKF 31318/DFC70 | Without | Not recorded | Not recorded | Sheet metal | Not recorded | None |
| SKF 31318T103/DB31 | Without | Not recorded | Not recorded | Sheet metal | Not recorded | None |
| FAG 31318>A | Not recorded | Not recorded | Not recorded | Standard — Sheet steel cage, window cage, roller-guided | Not recorded | Not recorded |
| FAG 31318-H | Not recorded | PN — Normal (ISO 492:2023) | Not recorded | Standard — Sheet steel cage, window cage, roller-guided | Not recorded | Not recorded |
| FAG 31318-P5 | Not recorded | P5 — Class 5 (ISO 492:2023) | Not recorded | Standard — Sheet steel cage, window cage, roller-guided | Not recorded | Not recorded |
| FAG 31318-P5>A | Not recorded | P5 — Class 5 (ISO 492:2023) | Not recorded | Standard — Sheet steel cage, window cage, roller-guided | Not recorded | Not recorded |
| FAG 31318-XL | Not recorded | PN — Normal (ISO 492:2023) | Not recorded | Standard — Sheet steel cage, window cage, roller-guided | Not recorded | Not recorded |
| FAG 31318-XL>A | Not recorded | PN — Normal (ISO 492:2023) | Not recorded | Standard — Sheet steel cage, window cage, roller-guided | Not recorded | Not recorded |
| FAG 31318-XL-DF-A0-35 | Not recorded | PN — Normal (ISO 492:2023) | Not recorded | Standard — Sheet steel cage, window cage, roller-guided | Not recorded | Not recorded |
| FAG 31318-XL-P5 | Not recorded | P5 — Class 5 (ISO 492:2023) | Not recorded | Standard — Sheet steel cage, window cage, roller-guided | Not recorded | Not recorded |
| FAG 31318-XL-P5>A | Not recorded | P5 — Class 5 (ISO 492:2023) | Not recorded | Standard — Sheet steel cage, window cage, roller-guided | Not recorded | Not recorded |
How to compare these values
- Use the displayed dimension names and original symbols. Housing length L, height H2 and flange width are not bearing outside diameter D. A catalogue width with an unverified symbol must not be assumed to be inner-ring width B or assembly width T. Open the product record for mounting dimensions and geometry.
- Inch values are calculated from the recorded millimetres using 25.4 mm per inch, rounded to six decimal places. They do not change a metric bearing into an inch-series bearing. Gram values are converted from the recorded mass in kilograms.
- C and C0 describe different rating conditions. They are not a single safe working-load limit and cannot replace an application load calculation.
- Reference and limiting speeds are separate catalogue values. The source grease/oil context is shown where recorded. Lubricant, seals, loads, fit, clearance and cooling affect the usable operating speed.
- A common base number does not prove equivalent seals, clearance, precision, material or interchangeability. Open the full designation for these fields.
Related prefix matches — other model numbers may appear
These discovery results can contain a longer number or a different component. They are not specifications for the requested exact model. Open the complete product to inspect its original geometry.
31318
Tapered roller bearing
View full technical record →TIMKEN31318
Tapered roller bearing
View full technical record →SKF31318
Single row tapered roller bearing
View full technical record →FAG31318>A
Tapered roller bearing
View full technical record →SKF31318/DF
Matched tapered roller bearings arranged face-to-face
View full technical record →SKF31318/DFC185
Matched tapered roller bearings arranged face-to-face
View full technical record →SKF31318/DFC70
Matched tapered roller bearings arranged face-to-face
View full technical record →FAG31318-H
Tapered roller bearing
View full technical record →FAG31318-P5
Tapered roller bearing
View full technical record →FAG31318-P5>A
Tapered roller bearing
View full technical record →SKF31318T103/DB31
Matched tapered roller bearings arranged back-to-back
View full technical record →FAG31318-XL
Tapered roller bearing
View full technical record →Check the drawing before substituting
Nominal dimensions are not shaft-fit tolerances. Different variants can add grooves, flanges, wider rings or assembly components. When the table has different dimensions, the complete designation—not the shared prefix—controls.
Reference basis & data limits
Manufacturer terminology is retained in the product records. Technical reference basis: JTEKT Basic Bearing Knowledge (boundary dimensions, tolerance classes and lubrication); NSK Bearing ABCs (lubrication, designations and clearance); NTN technical FAQs (closure codes and component interchange); SKF rolling-bearing selection and maintenance references.
Selection workflows and catalogue grouping are BearingScope editorial aids. Verify the current drawing and application requirements before using a candidate. Missing database information is not converted into an assumed match.