Printed from Kezuriba (kezuriba.net/en/threads/pins/)
Parallel pins: dimensions and tolerances
Parallel pins locate parts against each other. Their nominal diameters follow their own series (0.6–50 mm), separate from thread sizes. The pin diameter tolerance is m6 for type A and h7 or h8 for type B; together with the hole tolerance it sets the fit.
Parallel pins (JIS B 1354): diameter tolerance and chamfer
In mm. Tolerances are given as “upper / lower deviation”.
| Nominal d | Type A (m6) | Type B h7OTSUKA WORKS | Type B h8Himeno Seikosho | Chamfer c (approx.) | Type A end a (approx.) | Source |
|---|---|---|---|---|---|---|
| 0.6 | +0.008 / +0.002 | — | 0 / -0.014 | 0.12 | 0.08 | [2] |
| 0.8 | +0.008 / +0.002 | — | 0 / -0.014 | 0.16 | 0.1 | [2] |
| 1 | +0.008 / +0.002 | 0 / -0.01 | 0 / -0.014 | 0.2 | 0.12 | [1][2] |
| 1.2 | +0.008 / +0.002 | 0 / -0.01 | 0 / -0.014 | 0.25 | 0.16 | [1][2] |
| 1.5 | +0.008 / +0.002 | 0 / -0.01 | 0 / -0.014 | 0.3 | 0.2 | [1][2] |
| 1.6 | +0.008 / +0.002 | 0 / -0.01 | 0 / -0.014 | 0.3 | 0.2 | [1][2] |
| 2 | +0.008 / +0.002 | 0 / -0.01 | 0 / -0.014 | 0.35 | 0.25 | [1][2] |
| 2.5 | +0.008 / +0.002 | 0 / -0.01 | 0 / -0.014 | 0.4 | 0.3 | [1][2] |
| 3 | +0.008 / +0.002 | 0 / -0.01 | 0 / -0.014 | 0.5 | 0.4 | [1][2] |
| 4 | +0.012 / +0.004 | 0 / -0.012 | 0 / -0.018 | 0.63 | 0.5 | [1][2] |
| 5 | +0.012 / +0.004 | 0 / -0.012 | 0 / -0.018 | 0.8 | 0.63 | [1][2] |
| 6 | +0.012 / +0.004 | 0 / -0.012 | 0 / -0.018 | 1.2 | 0.8 | [1][2] |
| 8 | +0.015 / +0.006 | 0 / -0.015 | 0 / -0.022 | 1.6 | 1 | [1][2] |
| 10 | +0.015 / +0.006 | 0 / -0.015 | 0 / -0.022 | 2 | 1.2 | [1][2] |
| 12 | +0.018 / +0.007 | 0 / -0.018 | 0 / -0.027 | 2.5 | 1.6 | [1][2] |
| 13 | +0.018 / +0.007 | 0 / -0.018 | 0 / -0.027 | 2.5 | 1.6 | [1][2] |
| 16 | +0.018 / +0.007 | 0 / -0.018 | 0 / -0.027 | 3 | 2 | [1][2] |
| 20 | +0.021 / +0.008 | 0 / -0.021 | 0 / -0.033 | 3.5 | 2.5 | [1][2] |
| 25 | +0.021 / +0.008 | 0 / -0.021 | 0 / -0.033 | 4 | 3 | [1][2] |
| 30 | +0.021 / +0.008 | 0 / -0.021 | 0 / -0.033 | 5 | 4 | [1][2] |
| 40 | +0.025 / +0.009 | — | 0 / -0.039 | 6.3 | 5 | [2] |
| 50 | +0.025 / +0.009 | — | 0 / -0.039 | 8 | 6.3 | [2] |
- For type B, the OTSUKA WORKS table gives h7 and the Himeno Seikosho table gives h8, both presented as JIS B 1354:1988. The current JIS B 1354:2012 (aligned with ISO 2338) is reported to use h8 for type B, so check the standard itself before putting it on a drawing.
- Nominal 13 is from the old series. Diameters 0.6, 0.8, 40 and 50 appear only in the Himeno Seikosho table, which also lists type C (h11).
- Length tolerance: ±0.25 for ℓ = 2–10, ±0.5 for 12–50 and ±0.75 for 55–200 (both makers agree). Surface roughness 0.8a for types A and B, 3.2a for type C (OTSUKA WORKS drawing).
The tolerance values are the same as the shaft tolerance classes m6, h7 and h8 (ISO 286 / JIS B 0401). To check the fit with a hole, use the fits calculator.
Hardness of parallel pins
| Steel, not heat-treated | HV125–245 |
|---|---|
| Steel, hardened and tempered | HV255–327 |
| Stainless steel | HV208–280 |
Hardened dowel pins (Unbrako)
Hardened dowel pins equivalent to ANSI B18.8.5M, ISO 8734 and DIN 6325 (surface 60 HRC min., core 50–58 HRC). In mm; shear load in kN.[3]
| Nominal | Pin dia. max. – min. | Recommended hole max. – min. | Point dia. max. – min. | Crown height max., radius min. | Single shear load |
|---|---|---|---|---|---|
| 3 | 3.008 – 3.003 | 3 – 2.987 | 2.9 – 2.6 | 0.8, 0.3 | 7.4 |
| 4 | 4.009 – 4.004 | 4 – 3.987 | 3.9 – 3.6 | 0.9, 0.4 | 13.2 |
| 5 | 5.009 – 5.004 | 5 – 4.987 | 4.9 – 4.6 | 1, 0.4 | 20.6 |
| 6 | 6.01 – 6.004 | 6 – 5.987 | 5.8 – 5.4 | 1.1, 0.4 | 29.7 |
| 8 | 8.012 – 8.006 | 8 – 7.987 | 7.8 – 7.4 | 1.3, 0.5 | 52.5 |
| 10 | 10.012 – 10.006 | 10 – 9.987 | 9.8 – 9.4 | 1.4, 0.6 | 82.5 |
| 12 | 12.013 – 12.007 | 12 – 11.985 | 11.8 – 11.4 | 1.6, 0.6 | 119 |
| 16 | 16.013 – 16.007 | 16 – 15.985 | 15.8 – 15.3 | 1.8, 0.8 | 211 |
| 20 | 20.014 – 20.008 | 20 – 19.983 | 19.8 – 19.3 | 2, 0.8 | 330 |
| 25 | 25.014 – 25.008 | 25 – 24.983 | 24.8 – 24.3 | 2.3, 1 | 515 |
- The recommended hole is smaller than the pin, giving an interference fit. Press the pins in rather than hammering them (Unbrako’s caution).
- Shear loads are for single shear, calculated with a shear strength of 1050 MPa.
Related pages
Thread dimensions, tightening torque and washers by size are on the thread pages; torque and preload in the bolt torque calculator.