RMA Tolerance Chart
Metric Tolerances (mm)
| Nominal Dimension | A1 | A2 | A3 | A4 | |||||
|---|---|---|---|---|---|---|---|---|---|
| above | up to andincluding | Fixed | Closure | Fixed | Closure | Fixed | Closure | Fixed | Closure |
| 0 | 10 | 0.1 | 0.13 | 0.16 | 0.2 | 0.2 | 0.32 | 0.32 | 0.8 |
| 10 | 16 | 0.13 | 0.16 | 0.2 | 0.25 | 0.25 | 0.4 | 0.4 | 0.9 |
| 16 | 25 | 0.16 | 0.2 | 0.2 | 0.32 | 0.32 | 0.5 | 0.5 | 1 |
| 25 | 40 | 0.2 | 0.25 | 0.32 | 0.4 | 0.4 | 0.63 | 0.63 | 1.12 |
| 40 | 63 | 0.25 | 0.32 | 0.4 | 0.5 | 0.5 | 0.8 | 0.8 | 1.25 |
| 63 | 100 | 0.32 | 0.4 | 0.5 | 0.63 | 0.63 | 1 | 1.1 | 1.4 |
| 100 | 160 | 0.4 | 0.5 | 0.63 | 0.8 | 0.8 | 1.25 | 1.25 | 1.6 |
| 160 & over (Multiply by) | x .004 | x .005 | x .005 | x .008 | x .008 | x .010 |
Inch Tolerances (in)
| Nominal Dimension | A1 | A2 | A3 | A4 | |||||
|---|---|---|---|---|---|---|---|---|---|
| above | up to and including | Fixed | Closure | Fixed | Closure | Fixed | Closure | Fixed | Closure |
| 0 | 0.40 | 0.004 | 0.005 | 0.006 | 0.008 | 0.008 | 0.013 | 0.013 | 0.032 |
| 0.40 | 0.63 | 0.005 | 0.006 | 0.008 | 0.010 | 0.010 | 0.016 | 0.016 | 0.036 |
| 0.63 | 1.00 | 0.006 | 0.006 | 0.010 | 0.013 | 0.013 | 0.020 | 0.020 | 0.040 |
| 1.00 | 1.60 | 0.008 | 0.010 | 0.013 | 0.016 | 0.016 | 0.025 | 0.025 | 0.045 |
| 1.60 | 2.50 | 0.010 | 0.013 | 0.016 | 0.020 | 0.020 | 0.032 | 0.032 | 0.050 |
| 2.50 | 4.00 | 0.013 | 0.016 | 0.020 | 0.025 | 0.025 | 0.040 | 0.040 | 0.056 |
| 4.00 | 6.30 | 0.016 | 0.020 | 0.025 | 0.032 | 0.032 | 0.050 | 0.050 | 0.063 |
| 6.30 & over (Multiply by) | x .004 | x .005 | x .005 | x .008 | x .008 | x .010 |
Table 12. Summary of RMA Drawing Designations Extruded Rubber Products
| RMA Class | Dimensional Tolerance* Table 13 | CutLength Tolerance* Table 16 | SplicedLength Tolerance* Table 16 | MandrelCured* Table 20 |
|---|---|---|---|---|
| 1 | E1 | L1 | S1 | EN1 |
| 2 | E2 | L2 | S2 | EN2 |
| 3 | E3 | L3 | S3 | EN3 |
| - | - | - | - | - |
Table 13. Standard Cross-Sectional Tolerance
| RMA Class | 1 - High Precision | 2 - Precision | 3 - Commercial |
|
|---|---|---|---|---|
| Drawing Designation | E1 | E2 | E3 | |
| Dimensions (in Millimeters) | ||||
| Above | Up to and including | |||
| 0 | 1.5 | +0.15 | +0.25 | +0.4 |
| 1.5 | 2.5 | 0.20 | 0.35 | 0.50 |
| 2.5 | 4 | 0.25 | 0.40 | 0.70 |
| 4 | 6.3 | 0.35 | 0.50 | 0.80 |
| 6.3 | 10 | 0.40 | 0.70 | 1.00 |
| 10 | 16 | 0.50 | 0.80 | 1.30 |
| 16 | 25 | 0.70 | 1.00 | 1.60 |
| 25 | 40 | 0.80 | 1.30 | 2.00 |
| 40 | 63 | 1.00 | 1.60 | 2.50 |
| 63 | 100 | 1.30 | 2.00 | 3.20 |
| RMA Class | 1 - High Precision | 2 - Precision | 3 - Commercial | |
| Drawing Designation | E1 | E2 | E3 | |
| Dimensions (in Inches) | ||||
| Above | Up to and including | |||
| 0 | 0.06 | +0.006 | +0.010 | +0.015 |
| 0.06 | 0.10 | 0.008 | 0.014 | 0.020 |
| 0.10 | 0.16 | 0.010 | 0.016 | 0.027 |
| 0.16 | 0.25 | 0.014 | 0.020 | 0.031 |
| 0.25 | 0.39 | 0.016 | 0.027 | 0.039 |
| 0.39 | 0.63 | 0.020 | 0.031 | 0.051 |
| 0.63 | 0.98 | 0.027 | 0.039 | 0.063 |
| 0.98 | 1.57 | 0.031 | 0.051 | 0.079 |
| 1.57 | 2.48 | 0.039 | 0.063 | 0.098 |
| 2.48 | 3.94 | 0.051 | 0.079 | 0.126 |
Table 16. Cut Length tolerance for unspliced extrusion
| 1 - HighPrecision 2 -Precision 3 - Commercial | ||||
|---|---|---|---|---|
| Drawing Designation. | L1 | L2 | L3 | |
| Length (in Millimeters) | ||||
| Above | Up to and including | |||
| 0 | 40 | +0.7 | +0.04 | +1.6 |
| 40 | 63 | 0.08 | 1.3 | 2.0 |
| 63 | 100 | 1.0 | 1.6 | 2.5 |
| 100 | 160 | 1.3 | 2.0 | 3.2 |
| 160 | 250 | 1.6 | 2.5 | 4.0 |
| 250 | 400 | 2.0 | 3.2 | 5.0 |
| 400 | 630 | 2.5 | 4.0 | 6.3 |
| 630 | 1000 | 3.2 | 5.0 | 10.0 |
| 1000 | 1600 | 4.0 | 6.3 | 12.5 |
| 1600 | 2500 | 5.0 | 10.0 | 16.0 |
| 2500 | 4000 | 6.3 | 12.5 | 20.0 |
| 4000 | 0.16% | 0.32% | 0.50% | |
| Length (in Inches) | ||||
| Above | Up to and including | |||
| 1 | 1.6 | +0.03 | +0.04 | +0.06 |
| 1.6 | 2.5 | 0.03 | 0.05 | 0.08 |
| 2.5 | 4 | 0.04 | 0.06 | 0.10 |
| 4 | 6.3 | 0.05 | 0.08 | 0.13 |
| 6.3 | 10 | 0.06 | 0.10 | 0.16 |
| 10 | 16 | 0.8 | 0.13 | 0.20 |
| 16 | 25 | 0.10 | 0.16 | 0.25 |
| 25 | 40 | 0.13 | 0.20 | 0.40 |
| 40 | 63 | 0.16 | 0.25 | 0.50 |
| 63 | 100 | 0.20 | 0.40 | 0.63 |
| 100 | 160 | 0.25 | 0.50 | 0.80 |
| 160 | 0.16% | 0.32% | 0.50% | |
Table 18. Spliced Length Tolerances
| RMA Class | 1 - High Precision | 2 - Precision | 3 - Commercial | |
|---|---|---|---|---|
| Drawing Designation | S1 | S2 | S3 | |
| Millimeters | ||||
| Above | Up to and including | |||
| 0 | 250 | +302 | +3.2 | +7.1 |
| 250 | 400 | 4.0 | 7.1 | 8.0 |
| 400 | 630 | 5.0 | 8.0 | 9.0 |
| 630 | 1000 | 6.3 | 9.0 | 10.0 |
| 1000 | 1600 | 8.0 | 10.0 | 11.2 |
| 1600 | 2500 | 10.0 | 11.2 | 12.3 |
| 2500 | over | 012.5 | 12.5 | 16.0 |
| Inches | ||||
| Above | Up to and including | |||
| 0 | 10 | +.13 | +.25 | +.28 |
| 10 | 16 | .16 | .28 | .32 |
| 16 | 25 | .20 | .32 | .36 |
| 25 | 40 | .25 | .36 | .40 |
| 40 | 63 | .32 | .40 | .45 |
| 63 | 100 | .40 | .45 | .50 |
| 100 | over | .50 | .50 | .53 |
Table 20. Tolerances on Internal Dimensions of Mandrel-Supported Extrusions
| RMA Class | 1 - High Precision | 2 - Commercial | 3 - Non-Critical | |
|---|---|---|---|---|
| Drawing Designation | EN1 | EN2 | EN3 | |
| Nominal Dimensions (in Millimeters) |
||||
| Above | Up to and including | |||
| 0 | 4 | +0.20 | +0.20 | +0.35 |
| 4 | 6.3 | 0.20 | 0.25 | 0.40 |
| 6.3 | 10 | 0.25 | 0.35 | 0.50 |
| 10 | 16 | 0.35 | 0.40 | 0.70 |
| 16 | 25 | 0.40 | 0.50 | 0.80 |
| 25 | 40 | 0.50 | 0.70 | 1.00 |
| 40 | 63 | 0.70 | 0.80 | 1.30 |
| 63 | 100 | 0.80 | 1.00 | 1.60 |
| 100 | 160 | 1.00 | 1.30 | 2.00 |
| 160 | 0.6% | 0.8% | 1.2% | |
| Nominal Dimensions (in Inches) | ||||
| Above | Up to and including | |||
| 0 | 0.16 | +0.008 | +0.08 | +0.014 |
| 0.16 | 0.25 | 0.008 | 0.010 | 0.016 |
| 0.25 | 0.40 | 0.010 | 0.014 | 0.020 |
| 0.4 | 0.63 | 0.014 | 0.016 | 0.028 |
| 0.63 | 1.00 | 0.016 | 0.020 | 0.032 |
| 1.00 | 1.6 | 0.020 | 0.028 | 0.040 |
| 1.6 | 2.5 | 0.028 | 0.032 | 0.051 |
| 2.5 | 4.00 | 0.032 | 0.040 | 0.063 |
| 4.00 | 6.30 | 0.040 | 0.051 | 0.079 |
| 6.30 | 0.6% | 0.8% | 1.2% | |
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