Importance of Fit Accuracy
The accuracy of the fits and the geometrically correct design of all connecting parts are decisive for bearing function. Errors in the adjacent construction can substantially increase the friction torque.
The actual bearing outer diameter is provided in the inspection report supplied with each bearing.
Housing Dimension Diagram
Design Notes
- Envelope condition applies - Dimensional tolerances include form tolerance requirements (Envelope requirement E applies).
- Countersink for threaded holes - Note the countersinking of the threaded holes.
- Bearing diameter D1 - Note the bearing diameter D1 in the data sheet drawing, and ensure that there is sufficient distance between the rotating bearing ring and the adjacent construction.
- Surface roughness - Ra 0.8 μm (mating surfaces).
Outer Ring Stationary (NGS Series)
When the outer ring is stationary, it is possible to dispense with the fit in the housing, or alternatively to choose a G7 clearance fit. For the specific tolerances, refer to the "Outer Ring Stationary Tolerance G7" column in the tolerance table below.
Outer Ring Rotates (NGS-SBI Series)
Running Accuracy Requirements
For maximum running accuracy with a rotating outer ring, the fit clearance should approach zero (0 μm) to prevent an increase in radial runout.
For normal running accuracy or a rotating outer ring, design the housing according to the tolerance table below.
Dynamic Property Requirements
- For swiveling operation and a rotating outer ring, design the housing according to the tolerance table.
- At higher speeds and longer duty cycles with a rotating outer ring, the interference fit must not exceed 5 μm.
- For the highest speeds and longer duty cycles, a clearance of 0 μm should be aimed for; this requires a matched selection of bearing and shaft.
- The actual bearing dimensions can be found in the bearing report.
Housing Fit Tolerance Table
- Da: Housing (nominal) bore diameter, i.e. bearing outer diameter [mm]
- Outer Ring Stationary Tolerance G7: Upper / lower deviation of the G7 fit band [mm] (both positive = clearance fit)
- Outer Ring Rotating Tolerance: Housing upper deviation (positive = permissible clearance) / lower deviation (negative = permissible interference) [mm]
- J1: Pitch circle of the mounting threads [mm]
- D1min: Minimum shoulder diameter, ensuring safe clearance to the rotating ring [mm]
- T1: Roundness tolerance [μm]
- T3: Perpendicularity tolerance [μm]
- Rmax: Maximum corner radius [mm]
| Model | Da [mm] | Outer Ring Stationary Tol. G7 [mm] | Outer Ring Rotating Tol. [mm] | J1 [mm] | D1min [mm] | T1 [μm] | T3 [μm] | Rmax [mm] | ||
|---|---|---|---|---|---|---|---|---|---|---|
| Upper dev. | Lower dev. | Upper dev. | Lower dev. | |||||||
| AXRY 120-NGS (-SBI) | 210 | +0.061 | +0.015 | +0.007 | -0.005 | 195 | 185.5 | 4 | 6 | 0.1 |
| AXRY 180-NGS (-SBI) | 280 | +0.069 | +0.017 | +0.011 | -0.005 | 260 | 244.5 | 5 | 7 | 0.1 |
| AXRY 200-NGS (-SBI) | 300 | +0.069 | +0.017 | +0.011 | -0.005 | 285 | 274.5 | 6 | 8 | 0.1 |
| AXRY 260-NGS (-SBI) | 385 | +0.075 | +0.018 | +0.013 | -0.005 | 365 | 345.5 | 6 | 8 | 0.3 |
| AXRY 325-NGS (-SBI) | 450 | +0.083 | +0.020 | +0.015 | -0.005 | 430 | 415.5 | 6 | 8 | 0.3 |
| AXRY 395-NGS (-SBI) | 525 | +0.092 | +0.022 | +0.017 | -0.005 | 505 | 486.5 | 6 | 8 | 0.3 |
| AXRY 460-NGS (-SBI) | 600 | +0.092 | +0.022 | +0.017 | -0.005 | 580 | 561 | 6 | 8 | 0.3 |
| AXRY 580-NGS (-SBI) | 750 | +0.104 | +0.024 | +0.019 | -0.005 | 720 | 701 | 8 | 10 | 1 |
| AXRY 650-NGS (-SBI) | 870 | +0.116 | +0.026 | +0.021 | -0.005 | 830 | 801 | 8 | 10 | 1 |
Related Sections
- Recommended Fits for Shaft - Shaft fit tolerance selection
- Adjacent Construction Design - Design principles and accuracy requirements
- Bearing Commissioning - Run-in and verification procedures