ISO 286 · transition fit · IT5
k5 shaft tolerance
The k5 limits we cut to at every common nominal, computed from the ISO 286 fundamental deviation for k and the IT5 grade. Same numbers the configurator stamps on a k5 diameter.
k5 is a transition class: the band crosses or sits just above nominal, so the shaft is snug in a nominal-size bore and may need a light press. The letter k fixes where the band sits relative to nominal (the fundamental deviation); the grade 5 fixes how wide it is (IT5). Both come from the ISO 286 tables and scale with diameter, which is why one page per class, with every nominal, is more useful than a single number.
At a 1″ nominal the k5 band is +.0004 to +.0001: the shaft measures between 1.0001″ and 1.0004″, a 0.0004″ window. The table gives the same limits at the inch and metric nominals we turn most.
Pick k5 on any diameter in the configurator and the drawing carries exactly these limits; the engine computes them from the standard for the diameter you enter, not from this table.
k5 limits by nominal diameter
| Nominal Ø | Upper dev. | Lower dev. | Max Ø (in) | Min Ø (in) | Band (in) |
|---|---|---|---|---|---|
| 1/4″ (0.25) | +.0003 | +.0000 | 0.2503 | 0.25 | 0.0002 |
| 3/8″ (0.375) | +.0003 | +.0000 | 0.3753 | 0.375 | 0.0002 |
| 1/2″ (0.5) | +.0004 | +.0000 | 0.5004 | 0.5 | 0.0003 |
| 5/8″ (0.625) | +.0004 | +.0000 | 0.6254 | 0.625 | 0.0003 |
| 3/4″ (0.75) | +.0004 | +.0001 | 0.7504 | 0.7501 | 0.0004 |
| 7/8″ (0.875) | +.0004 | +.0001 | 0.8754 | 0.8751 | 0.0004 |
| 1″ (1) | +.0004 | +.0001 | 1.0004 | 1.0001 | 0.0004 |
| 1-1/8″ (1.125) | +.0004 | +.0001 | 1.1254 | 1.1251 | 0.0004 |
| 1-1/4″ (1.25) | +.0005 | +.0001 | 1.2505 | 1.2501 | 0.0004 |
| 1-3/8″ (1.375) | +.0005 | +.0001 | 1.3755 | 1.3751 | 0.0004 |
| 1-1/2″ (1.5) | +.0005 | +.0001 | 1.5005 | 1.5001 | 0.0004 |
| 1-3/4″ (1.75) | +.0005 | +.0001 | 1.7505 | 1.7501 | 0.0004 |
| 2″ (2) | +.0006 | +.0001 | 2.0006 | 2.0001 | 0.0005 |
| 2-1/2″ (2.5) | +.0006 | +.0001 | 2.5006 | 2.5001 | 0.0005 |
| 3″ (3) | +.0006 | +.0001 | 3.0006 | 3.0001 | 0.0005 |
| 4″ (4) | +.0007 | +.0001 | 4.0007 | 4.0001 | 0.0006 |
| Metric nominals (limits in inches) | |||||
| 20 mm (0.7874″) | +.0004 | +.0001 | 0.7878 | 0.7875 | 0.0004 |
| 25 mm (0.9843″) | +.0004 | +.0001 | 0.9847 | 0.9843 | 0.0004 |
| 30 mm (1.1811″) | +.0004 | +.0001 | 1.1815 | 1.1812 | 0.0004 |
| 35 mm (1.378″) | +.0005 | +.0001 | 1.3785 | 1.378 | 0.0004 |
| 40 mm (1.5748″) | +.0005 | +.0001 | 1.5753 | 1.5749 | 0.0004 |
| 45 mm (1.7717″) | +.0005 | +.0001 | 1.7722 | 1.7717 | 0.0004 |
| 50 mm (1.9685″) | +.0005 | +.0001 | 1.969 | 1.9686 | 0.0004 |
| 55 mm (2.1654″) | +.0006 | +.0001 | 2.1659 | 2.1654 | 0.0005 |
| 60 mm (2.3622″) | +.0006 | +.0001 | 2.3628 | 2.3623 | 0.0005 |
| 65 mm (2.5591″) | +.0006 | +.0001 | 2.5596 | 2.5591 | 0.0005 |
Deviations from nominal in inches at 0.0001 in resolution; max and min are the finished diameter limits. Metric nominals are converted and the limits shown in inches.
Applications and finish targets for k5
| Application | Finish target (Ra, µin) |
|---|---|
| Bearing seat (inner ring on a rotating shaft) | 32 |
Part of Shaft fits and tolerances. Other pages in the series: d9 · e8 · f7 · g6 · h6 · h7 · h8 · js6 · j6 · k6 · m6 · n6 · p6 · r6 · s6 · 1/4″ · 3/8″ · 1/2″ · 5/8″ · 3/4″ · 7/8″ · 1″ · 1-1/8″ · 1-1/4″ · 1-3/8″ · 1-1/2″ · 1-3/4″ · 2″ · 2-1/2″ · 3″ · 4″ · 20 mm · 25 mm · 30 mm · 35 mm · 40 mm · 45 mm · 50 mm · 55 mm · 60 mm · 65 mm.
Where k5 is used
These are the applications the configurator associates with k5, with the surface-finish target it applies to that diameter. A fit class sets size; the finish is what makes the size hold in service.
Transition fit, by the numbers
A k5 shaft against a nominal (H-basis) bore ranges from a slight clearance to a slight interference depending on where each part lands in its band; at 1″ the shaft itself spans 1.0001″ to 1.0004″. It seats without slop and still comes apart with an arbor press, which is the point.
Catalog parts that carry a k5 diameter as shipped: Pump Shaft to Fit Goulds 3196 ST (1.378″), Pump Shaft to Fit Goulds 3196 MT (1.772″), Pump Shaft to Fit Goulds 3196 LT (2.166″), Pump Shaft to Fit Goulds 3196 XLT (2.559″), Pump Shaft to Fit Goulds 3196 X17 (2.559″), Pump Shaft to Fit Durco Mark 3 Group 1 (1.378″), Pump Shaft to Fit Durco Mark 3 Group 2 (1.969″), Pump Shaft to Fit Durco Mark 3 Group 3 (2.756″), Pump Shaft to Fit Summit 2196 STO (1.378″), Pump Shaft to Fit Summit 2196 MTO (1.772″), Pump Shaft to Fit Summit 2196 LTO (2.166″), Pump Shaft to Fit Summit 2196 XLO (2.559″), Pump Shaft to Fit Griswold 811S (1.378″), Pump Shaft to Fit Griswold 811M (1.772″), Pump Shaft to Fit Griswold 811L (2.166″), Pump Shaft to Fit Griswold 811XL (2.559″), Pump Shaft to Fit PumpWorks PWA STi (1.378″), Pump Shaft to Fit PumpWorks PWA MTi (1.772″), Pump Shaft to Fit PumpWorks PWA LTi (2.166″), Pump Shaft to Fit PumpWorks PWA XLTi (2.559″), Pump Shaft to Fit Goulds 3796 STi (1.378″), Pump Shaft to Fit Goulds 3796 MTi (1.772″), Pump Shaft to Fit Goulds 3796 LTi (2.166″), Pump Shaft to Fit Goulds 3996 ST (1.378″), and 1 more.
Frequently Asked Questions
These references are for specifying a part; every value here is one the configurator applies when you build one. Numbers are representative of the standard; check them against your part and its mating components before ordering. See all guides on the guides page.