Roller Bearings
Designed to handle combined radial and axial loads with tapered raceways for heavy-duty applications.
Tapered Roller Bearings handle combined radial and axial loads simultaneously. The tapered design creates line contact between rollers and raceways, providing high load capacity and excellent resistance to axial forces.
Metric tapered roller bearings follow ISO 355 with a 5-digit base number plus suffix letters describing tolerance, contact angle, internal design and special features. Inch-series bearings follow the Timken designation system (e.g. JM207049/JM207010 = cone/cup). The most common suffixes used at quotation are below.
| Suffix / Code | Meaning |
|---|---|
| 30200 / 30300 | ISO 355 dimension series prefix |
| 32200 / 32300 | Wide variant of 30200 / 30300 |
| 32900 | Low-section series |
| B | Increased contact angle |
| X | ISO 355 redesigned to original dimension series |
| J / JM / HM / LM / M / NA | Inch-series cone/cup prefix (Timken-pattern) |
| TDO | Two-row, double-cup, single-cone-each-side |
| TDI | Two-row, double-cone, single-cup |
| TNA | Four-row tapered roller bearing assembly |
| C2 / CN / C3 / C4 | Radial internal clearance class (ISO 5753-1) |
| P0 / P6 / P5 / P4 / P2 | Tolerance / precision class per ISO 492 |
| S0 / S1 / S2 | Heat-stabilised |
| GR | Pre-greased / pre-lubricated |
Tapered roller bearings are normally adjusted at mounting rather than running on a fixed pre-set clearance — but pre-set TDO/TDI hub units and four-row mill assemblies are supplied with a defined radial clearance class. The right class depends on the operating temperature, the housing fit and the shaft fit. Selecting too tight a class on a hot mill chock is a common cause of early heat-related failure.
| Class | Description |
|---|---|
| C2 | Smaller than normal |
| CN (Normal) | Normal clearance |
| C3 | Larger than CN |
| C4 | Larger than C3 |
| C5 | Larger than C4 |
Tapered roller bearings generate an axial force component when loaded radially due to their cone geometry. A second bearing mounted in opposition (face-to-face or back-to-back) is required to absorb this thrust force and provide a stable shaft system. The pair arrangement also allows adjustable preload for precision applications.
Single-row tapered roller bearings handle combined loads in one direction and are typically mounted in pairs for bidirectional support. Four-row designs are self-contained units with very high load capacity, specifically engineered for rolling mill work rolls and backup rolls where extreme radial and axial loads exist simultaneously.
Preload is set by adjusting the axial position of the bearing using shims, lock nuts, or spacers. Proper preload eliminates internal clearance to increase stiffness and load distribution. Too much preload causes excessive heat and reduced life; too little allows shaft play. Follow the manufacturer recommended axial displacement or starting torque values for your specific bearing series.
Tapered roller bearings are essential where combined radial and axial loads exist: automotive wheel hubs, gearbox shafts, differential assemblies, rolling mill chocks, crane trolley wheels, and heavy-duty conveyor pulleys. They are preferred over cylindrical roller bearings whenever significant thrust loads are present alongside radial loads.
Standard tapered roller bearings operate up to +150°C. For rolling mill applications with higher temperatures, heat-stabilised variants (S1 to +200°C, S2 to +250°C) maintain dimensional stability. Above +120°C continuous, synthetic or high-temperature oil lubrication is recommended instead of standard grease.
Boundary dimensions per ISO 355 / ISO 10317 across the metric series: 30200 (light, ~12° contact angle), 30300 (heavy), 32200 (wide light), 32300 (wide heavy) and 32900 (low-section). Width column shows total bearing width T. Inch-series (Timken-pattern J/JM/HM/LM/M/NA designations) and matched cup-and-cone replacement sets are available on request.
| Bearing No. | Bore (d) mm | Outer (D) mm | Width (B) mm |
|---|---|---|---|
| 30203 | 17 | 40 | 13.25 |
| 30204 | 20 | 47 | 15.25 |
| 30205 | 25 | 52 | 16.25 |
| 30206 | 30 | 62 | 17.25 |
| 30207 | 35 | 72 | 18.25 |
| 30208 | 40 | 80 | 19.75 |
| 30209 | 45 | 85 | 20.75 |
| 30210 | 50 | 90 | 21.75 |
| 30211 | 55 | 100 | 22.75 |
| 30212 | 60 | 110 | 23.75 |
| 30213 | 65 | 120 | 24.75 |
| 30214 | 70 | 125 | 26.25 |
| 30215 | 75 | 130 | 27.25 |
| 30216 | 80 | 140 | 28.25 |
| 30217 | 85 | 150 | 30.5 |
Can't find what you need? We can source non-standard and custom bearings.
Self-aligning double-row bearings with barrel-shaped rollers for heavy radial loads, shock resistance, and up to 2° misalignment compensation in mining, steel, and energy applications.
High radial load capacity bearings using line contact between rollers and raceways for optimised stress distribution in industrial machinery.
Compact bearings with very long, thin rolling elements providing high radial load capacity in minimal radial space, ideal for space-constrained applications.
