SKF metric bearings
The designations of metric tapered roller bearings follow one of the following principles:
- The series designations in accordance with ISO 355 consist of a digit and two letters. The digit represents the contact angle. The two letters represent the diameter and width series, respectively. This is followed by a three-digit bore diameter d [mm]. The basic designations of SKF tapered roller bearings start with the letter T, e.g. T2ED 045.
- Designations established prior to 1977 are based on the system shown under SKF bearing designation, e.g. 32210.
- Metric bearings with the designation prefix J follow the ABMA designation system, which is used for inch bearings (→ ANSI/ABMA Std. 19.1).
SKF inch bearings
Inch tapered roller bearing designations are in accordance with ANSI/ABMA Std. 19.2.
Within a series:
- roller and cage assemblies are equal but the inner and outer rings can have different sizes and designs
- any inner ring with roller and cage assembly (cone) can be assembled with any outer ring (cup)
General:
- cup and cone have individual designations and can be supplied separately
- designations of cups and cones, as well as the series, consist of a three- to six-digit number, which may be prefixed to characterize a bearing series from extra-light to extra-heavy
-
complete bearing designation is an abbreviated combination of cone and cup designations;
it consists of the cone designation followed by the complete or parts of the cup designation, separated by an oblique stroke
SKF single row tapered roller bearing designation
SKF tapered roller bearings designation follow a system that may consist of a basic designation with or without one or more prefixes and/or suffixes.
| 1 | Prefixes |
| J | Metric bearing following the ABMA designation system (ANSI/ABMA Std. 19.2) |
| T | Metric bearing in accordance with ISO 355 |
| 2 | Basic designation |
| 3 | Suffixes - Internal design |
| B | Steep contact angle |
| 4 | Suffixes - External design (seals, snap ring groove etc.) |
| R | Flanged outer ring |
| X | Boundary dimensions changed to conform to ISO |
| 5 | Suffixes - Cage design |
| TN9 | Glass fibre reinforced PA66 cage, roller centred |
| TNH | Glass fibre reinforced PEEK cage, roller centred |
| 6.1 | Suffixes - Materials, heat treatment |
| HA1 | Case-hardened inner and outer rings |
| HA2 | Case-hardened outer ring |
| HA3 | Case-hardened inner ring |
| HA4 | Case-hardened inner and outer rings and rollers |
| HA5 | Case-hardened rollers |
| HB1 | Bainite-hardened inner and outer rings |
| HN3 | Inner ring with special surface heat treatment |
| L4B | Bearing rings and rollers with special surface coating |
| 6.2 | Suffixes - Accuracy, clearance, preload, quiet running |
|
/1 /-1 to /-3 /4 |
Deviating width tolerances of cups and cones for inch bearings |
| CL0 | Geometrical tolerances to ABMA tolerance class 0 (inch bearing) |
| CL00 | Geometrical tolerances to ABMA tolerance class 00 (inch bearing) |
| P5 | Geometrical tolerances to P5 tolerance class |
| U.. |
U combined with a one- or two-digit number identifies tighter total width tolerance, e.g.: U2 → +5/0 µm U4 → +10/0 µm |
| W | Modified ring width tolerance to +5/0 µm |
| 6.3 | Suffixes - Bearing sets, matched bearings (n.a.) |
| 6.4 | Suffixes - Stabilization (n.a.) |
| 6.5 | Suffixes - Lubrication (n.a.) |
| 6.6 | Suffixes - Other variants |
| CL7A | Pinion bearing, superseded by CL7C |
| CL7C | High-performance design |
| CLN | Tighter tolerances for ring widths and total (abutment) width in accordance with ISO tolerance class 6X |
| PEX | SKF Explorer bearing, used only when same-sized basic design bearing and SKF Explorer bearing are available |
| V001 | CL7C and /2 |
| VA321 | Optimized internal design |
| VA606 | Crowned raceway on the outer ring, logarithmic profile on the inner ring and special heat treatment |
| VA607 | Same as VA606, but other outside diameter tolerance |
| VB022 | Chamfer dimension of large outer ring side face 0,3 mm |
| VB026 | Chamfer dimension of large inner ring side face 3 mm |
| VB061 | Chamfer dimension of large inner ring side face 8 mm |
| VB134 | Chamfer dimension of large inner ring side face 1 mm |
| VB406 | Chamfer dimension of large inner ring side face 3 mm and of large outer ring side face 2 mm |
| VB481 | Chamfer dimension of large inner ring side face 8,5 mm |
| VC027 | Modified internal geometry for increased permissible misalignment |
| VC068 | Tighter geometrical tolerances and special heat treatment |
| VE141 | One locating slot (notch) in the outer ring |
| VE174 | One locating slot (notch) in the large side face of the outer ring, tighter geometrical tolerances |
| VQ051 | Modified internal geometry for increased permissible misalignment |
| VQ117 | Special radial and axial run-out tolerances |
| VQ267 | Tighter inner ring width tolerance to ± 25 µm |
| VQ492 | Special inner ring width tolerance |
| VQ494 | Tighter radial run-out tolerances |
| VQ495 | CL7C with tighter or shifted tolerance range for the outside diameter |
| VQ506 | Tighter inner ring width tolerance |
| VQ507 | CL7C with tighter or shifted tolerance range for the outside diameter |
| VQ523 | CL7C with tighter inner ring width tolerance and tighter or shifted tolerance range for the outside diameter |
| VQ601 | Geometrical tolerances to ABMA tolerance class 0 (inch bearing) |
