Technical Reference
Spherical Plain Bearing Fitting Tolerances — Bore and Shaft Reference
Read H-class bore and g/h-class shaft deviations by nominal diameter range. Use them as tolerance references, then choose the actual fit from the load path, ring behavior and surrounding structure.
Bore tolerance classes
Each cell shows lower / upper deviation for the nominal diameter range. H classes in this table use a zero lower deviation and a positive upper deviation.
| Diameter mm | Diameter inch | H5 mm | H5 inch | H6 mm | H6 inch | H7 mm | H7 inch | H8 mm | H8 inch |
|---|---|---|---|---|---|---|---|---|---|
| 3–6 | 0.1181–0.2362 | 0 / +0.005 | 0 / +0.0002 | 0 / +0.008 | 0 / +0.0003 | 0 / +0.012 | 0 / +0.0005 | 0 / +0.018 | 0 / +0.0007 |
| 6–10 | 0.2362–0.3937 | 0 / +0.006 | 0 / +0.0002 | 0 / +0.009 | 0 / +0.0003 | 0 / +0.015 | 0 / +0.0006 | 0 / +0.022 | 0 / +0.0008 |
| 10–18 | 0.3937–0.7087 | 0 / +0.008 | 0 / +0.0003 | 0 / +0.011 | 0 / +0.0004 | 0 / +0.018 | 0 / +0.0007 | 0 / +0.027 | 0 / +0.0010 |
| 18–30 | 0.7087–1.1811 | 0 / +0.009 | 0 / +0.0003 | 0 / +0.013 | 0 / +0.0005 | 0 / +0.021 | 0 / +0.0008 | 0 / +0.033 | 0 / +0.0013 |
| 30–50 | 1.1811–1.9685 | 0 / +0.011 | 0 / +0.0004 | 0 / +0.016 | 0 / +0.0006 | 0 / +0.025 | 0 / +0.0009 | 0 / +0.039 | 0 / +0.0015 |
| 50–80 | 1.9685–3.1496 | 0 / +0.013 | 0 / +0.0005 | 0 / +0.019 | 0 / +0.0007 | 0 / +0.030 | 0 / +0.0011 | 0 / +0.046 | 0 / +0.0018 |
| 80–120 | 3.1496–4.7244 | 0 / +0.015 | 0 / +0.0006 | 0 / +0.022 | 0 / +0.0009 | 0 / +0.035 | 0 / +0.0013 | 0 / +0.054 | 0 / +0.0021 |
Shaft tolerance classes
The shaft table gives upper / lower deviations for g5, g6, g7, h5, h6 and h7. The correct fit cannot be selected from the class name alone.
| Diameter mm | Diameter inch | g5 mm | g5 inch | g6 mm | g6 inch | g7 mm | g7 inch | h5 mm | h5 inch | h6 mm | h6 inch | h7 mm | h7 inch |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 3–6 | 0.1181–0.2362 | -0.004 / -0.009 | -0.0001 / -0.0003 | -0.004 / -0.012 | -0.0001 / -0.0004 | -0.004 / -0.016 | -0.0001 / -0.0006 | 0 / -0.005 | 0 / -0.0002 | 0 / -0.008 | 0 / -0.0003 | 0 / -0.012 | 0 / -0.0004 |
| 6–10 | 0.2362–0.3937 | -0.005 / -0.011 | -0.0002 / -0.0004 | -0.005 / -0.014 | -0.0002 / -0.0005 | -0.005 / -0.020 | -0.0002 / -0.0007 | 0 / -0.006 | 0 / -0.0002 | 0 / -0.009 | 0 / -0.0003 | 0 / -0.015 | 0 / -0.0006 |
| 10–18 | 0.3937–0.7087 | -0.006 / -0.014 | -0.0002 / -0.0005 | -0.006 / -0.017 | -0.0002 / -0.0006 | -0.006 / -0.024 | -0.0002 / -0.0009 | 0 / -0.008 | 0 / -0.0003 | 0 / -0.011 | 0 / -0.0004 | 0 / -0.018 | 0 / -0.0007 |
| 18–30 | 0.7087–1.1811 | -0.007 / -0.016 | -0.0002 / -0.0006 | -0.007 / -0.020 | -0.0002 / -0.0007 | -0.007 / -0.028 | -0.0002 / -0.0011 | 0 / -0.009 | 0 / -0.0003 | 0 / -0.013 | 0 / -0.0005 | 0 / -0.021 | 0 / -0.0008 |
| 30–50 | 1.1811–1.9685 | -0.009 / -0.020 | -0.0003 / -0.0007 | -0.009 / -0.025 | -0.0003 / -0.0009 | -0.009 / -0.034 | -0.0003 / -0.0013 | 0 / -0.011 | 0 / -0.0004 | 0 / -0.016 | 0 / -0.0006 | 0 / -0.025 | 0 / -0.0009 |
| 50–80 | 1.9685–3.1496 | -0.010 / -0.023 | -0.0004 / -0.0009 | -0.010 / -0.029 | -0.0004 / -0.0011 | -0.010 / -0.040 | -0.0004 / -0.0015 | 0 / -0.013 | 0 / -0.0005 | 0 / -0.019 | 0 / -0.0007 | 0 / -0.030 | 0 / -0.0011 |
| 80–120 | 3.1496–4.7244 | -0.012 / -0.027 | -0.0004 / -0.0010 | -0.012 / -0.034 | -0.0004 / -0.0013 | -0.012 / -0.047 | -0.0004 / -0.0018 | 0 / -0.015 | 0 / -0.0006 | 0 / -0.022 | 0 / -0.0008 | 0 / -0.035 | 0 / -0.0013 |
Fit caution: ring load direction, housing stiffness, temperature, assembly method, surface condition and the bearing construction can all change the appropriate fit. Confirm the ordered configuration before machining a production housing or shaft.
Need a fit reviewed?
Send the bearing model, shaft and housing drawing, load direction and operating temperature with the RFQ.
