Welcome to Arrow Engineering Components |
Call us: 0161 737 6969
Before we add this to your basket
In-house CNC boring and keyway cutting for pilot bore and taper lock hubs from 30 mm to 250 mm. Machined to your shaft size and fit class, inspected, and shipped ready to fit.
The service
Couplings, pulleys, sprockets and drive assemblies are supplied with a pilot bore or a taper lock seat. Our engineers open that bore to your finished diameter and cut the keyway to suit the shaft, so the part arrives ready to slide on rather than waiting on a local machine shop.
Work is carried out in our Manchester workshop with over 30 years of industrial machining and power transmission experience behind it. Bores are cut to size - not reamed to a fixed step - so any diameter in the range is achievable, including metric-to-imperial conversions.
Any diameter in range, including imperial equivalents.
Slotted after boring so the key sits true to the finished bore.
Bore and keyway gauged before the part leaves the bench.
Send a drawing and we work to it, tolerances included.
Interactive
Set the finished bore and fit class to see the standard keyway dimensions and the service band your job falls into.
Spec builder
Matching service band
BK-075
£74.84
Per hub, ex VAT. Two-hub couplings require two units.
Figures are standard values for parallel keys in a hub. Confirm against your drawing - interference fits, off-standard keyways and grub-screw positions can be quoted on request.
Reference
Standard parallel key sections and hub keyway depths against bore diameter. Keyway width is cut to JS9 as standard; P9 (interference) is available on request.
| Bore ø (mm) | Key b x h | Width b (JS9) | Hub depth t2 |
|---|---|---|---|
| >22 - 30 | 8 x 7 | 8 | 3.3 |
| >30 - 38 | 10 x 8 | 10 | 3.3 |
| >38 - 44 | 12 x 8 | 12 | 3.3 |
| >44 - 50 | 14 x 9 | 14 | 3.8 |
| >50 - 58 | 16 x 10 | 16 | 4.3 |
| >58 - 65 | 18 x 11 | 18 | 4.4 |
| >65 - 75 | 20 x 12 | 20 | 4.9 |
| >75 - 85 | 22 x 14 | 22 | 5.4 |
| >85 - 95 | 25 x 14 | 25 | 5.4 |
| >95 - 110 | 28 x 16 | 28 | 6.4 |
| >110 - 130 | 32 x 18 | 32 | 7.4 |
| >130 - 150 | 36 x 20 | 36 | 8.4 |
| >150 - 170 | 40 x 22 | 40 | 9.4 |
| >170 - 200 | 45 x 25 | 45 | 10.4 |
| >200 - 230 | 50 x 28 | 50 | 11.4 |
| >230 - 250 | 56 x 32 | 56 | 12.4 |
How it's done
We review your shaft size, fit class and hub type, and flag anything that won't clean up - thin wall sections, existing bores or off-standard keyways.
Hub is clocked true in a 4-jaw or soft-jaw fixture. Runout is indicated to =0.05 mm TIR before any metal is cut.
Roughing pass followed by a finish pass to your nominated tolerance, bored to size rather than reamed so we can hold any diameter in the range.
Keyway slotted to BS 4235 width and hub depth, deburred, and centred on the bore axis.
Bore verified with internal micrometer, keyway with plug and slip gauges. Dimensions recorded, then packed and shipped.
Materials
| Material | Status | Notes |
|---|---|---|
| Cast iron (GG20/25) | Standard | Most taper lock and pilot bore hubs |
| Mild / EN8 steel | Standard | Sprockets, weld-on hubs, flanges |
| Aluminium | Standard | Timing pulleys, light drives |
| Stainless 303/316 | On request | Slower cycle, quoted per job |
| Hardened >30 HRC | Not offered | Requires grinding, not machining |
Choosing a fit
Roughly +0.000 / +0.030 mm at 75 mm. Use for gearbox output shafts, pumps and any drive where hub runout matters.
Roughly +0.000 / +0.046 mm at 75 mm. Our default: slides on by hand or with light tapping, keyway carries the torque.
Roughly +0.000 / +0.074 mm at 75 mm. Suits slow-speed drives and hubs that are removed frequently.
Available on request where the hub must be heated or pressed on. Tell us the shaft's measured size so we can match it.
Pricing
Priced per hub and banded by finished bore diameter. All prices exclude VAT.
10 bands . 30-250 mm
£32.38
per hub, ex VAT£41.78
per hub, ex VAT£50.38
per hub, ex VAT£58.30
per hub, ex VAT£74.84
per hub, ex VAT£89.95
per hub, ex VAT£129.54
per hub, ex VAT£172.41
per hub, ex VAT£211.08
per hub, ex VAT£251.86
per hub, ex VATTechnical FAQ
Two. A flexible coupling has two hubs and each hub is a separate machining operation, so add the service twice - one per hub - and give both bore sizes in the order comments.
H8 covers most power transmission work and is our default. Choose H7 where the hub must locate precisely - gearbox output shafts, pumps, or where a light interference is used with a keyway. H9 suits slow-speed drives that are stripped often.
Yes, provided the finished size is larger than the existing bore and the remaining wall thickness is sound. Send the current bore size and we'll confirm before cutting.
By finished bore diameter, not by hub size. A 62 mm bore falls in the up-to-75mm band. Pricing is per hub and excludes VAT.
Bore diameter, tolerance class, keyway requirement (or shaft size so we can derive it), hub material, and whether the hub is supplied by you or bought with the order.
Send us the shaft size or a drawing and our engineers will spec it for you.
