DIN 6888 Woodruff Keys
DIN 6888 woodruff (semi-circular) keys, 1 x 1.4 through 10 x 16
Last updated: 2026-11
Specifications
Woodruff keys are the semi-circular disc keys that seat in a matching half-circle milling cut in the shaft — the deep pocket gives the key room to rock into alignment with the hub keyway, which is why tapered-shaft and pulley mountings use them. This reference tabulates DIN 6888 across the collected source's size ladder from 1 x 1.4 up to 10 x 16, where each designation reads key width b x hub diameter d 1. Per size the grids give the minimum key width b, the key height k (maximum equals the nominal size under the h 12 tolerance, with the minimum printed alongside), the hub diameter d 1, the approximate overall length L and the mass per 1000 units — the mass columns let you estimate shipping weight on bulk orders directly from the table. The source prints its approx. marks and one full-width-parenthesis cell verbatim on this page; we carry them as printed rather than cleaning them, so the table stays token-faithful to the collected source. Key material, hardness and whether the key is supplied ground or unground are per RFQ.
| Standard | DIN 6888 (woodruff keys), as tabulated by the collected source |
|---|---|
| Designations covered | 1 x 1.4, 1.5 x 2.6, 2 x 2.6, 2 x 3.7, 2.5 x 3.7, 3 x 3.7, 3 x 5, 3 x 6.5, 4 x 5, 4 x 6.5, 4 x 7.5, 5 x 6.5, 5 x 7.5, 5 x 9, 6 x 7.5, 6 x 9, 6 x 10, 6 x 11, 8 x 9, 8 x 11, 8 x 13, 10 x 11, 10 x 13, 10 x 16 (width x hub diameter) |
| Key width b | Minimum printed per size; maximum = nominal size under h 12 |
| Key height k | Max = nominal size (h 12), min printed per size |
| Length and mass | Approx. overall length L and mass per 1000 units printed per size |
| Not tabulated | Key material, hardness, shaft cut depth for the semicircular seat — per RFQ |
| Normal size b | 1 ×1.4 | 1.5 ×2.6 | 2 ×2.6 | |
|---|---|---|---|---|
| b | min | 0.975 | 1.475 | 1.975 |
| k | max=nominal size(h12) | 1.4 | 2.6 | 2.6 |
| k | min | 1.3 | 2.5 | 2.5 |
| d 1 | 4 | 7 | 7 | |
| L | ≈ | 3.82 | 6.76 | 6.76 |
| per 1000 units≈kg | 0.031 | 0.153 | 0.204 |
- Row 1 (b): designation cells print with spaces around the multiplication sign ("1 ×1.4") — the source's own spacing, carried verbatim
| Normal size b | 2 ×3.7 | -2.5 ×3.7 | 3 ×3.7 | |
|---|---|---|---|---|
| b | min | 1.975 | 2.475 | 2.975 |
| k | max=nominal size(h12) | 3.7 | 3.7 | 3.7 |
| k | min | 3.58 | 3.58 | 3.58 |
| d 1 | 10 | 10 | 10 | |
| L | ≈ | 9.66 | 9.66 | 9.66 |
| per 1000 units≈kg | 0.414 | 0.518 | 0.622 |
| Normal size b | 3 ×5 | 3 ×6.5 | 4 ×5 | |
|---|---|---|---|---|
| b | min | 2.975 | 2.975 | 3.97 |
| k | max=nominal size(h12) | 5 | 6.5 | 5 |
| k | min | 4.88 | 6.35 | 4.88 |
| d 1 | 13 | 16 | 13 | |
| L | ≈ | 12.56 | 15.72 | 12.65 |
| per 1000 units≈kg | 1.1 | 1.8 | 1.47 |
| Normal size b | 4 ×6.5 | 4 ×7.5 | 5 ×6.5 | |
|---|---|---|---|---|
| b | min | 3.97 | 3.97 | 4.97 |
| k | max=nominal size(h12) | 6.5 | 7.5 | 6.5 |
| k | min | 6.35 | 7.35 | 6.35 |
| d 1 | 16 | 19 | 16 | |
| L | ≈ | 15.72 | 18.57 | 15.72 |
| per 1000 units≈kg | 2.4 | 3.27 | 3.01 |
| Normal size b | 5 ×7.5 | 5 ×9 | 6 ×7.5 | |
|---|---|---|---|---|
| b | min | 4.97 | 4.97 | 5.97 |
| k | max=nominal size(h12) | 7.5 | 9 | 7.5 |
| k | min | 7.35 | 8.85 | 7.35 |
| d 1 | 19 | 22 | 19 | |
| L | ≈ | 18.57 | 21.63 | 18.57 |
| per 1000 units≈kg | 4.09 | 5.73 | 4.91 |
| Normal size b | 6 ×9 | 6 ×10 | 6 ×11 | |
|---|---|---|---|---|
| b | min | 5.97 | 5.97 | 5.97 |
| k | max=nominal size(h12) | 9 | （10） | 11 |
| k | min | 8.85 | 9.85 | 10.82 |
| d 1 | 22 | 25 | 28 | |
| L | ≈ | 21.63 | 24.49 | 27.35 |
| per 1000 units≈kg | 6.88 | 8.64 | 10.6 |
- Row 3 (k): cell prints full-width parentheses （10） (the source page's own character, verified in the live HTML) — carried verbatim, not normalized to ASCII
| Normal size b | 8 ×9 | 8 ×11 | 8 ×13 | |
|---|---|---|---|---|
| b | min | 7.964 | 7.964 | 7.964 |
| k | max=nominal size(h12) | 9 | 11 | 13 |
| k | min | 8.85 | 10.82 | 12.82 |
| d 1 | 22 | 28 | 32 | |
| L | ≈ | 21.63 | 27.35 | 31.43 |
| per 1000 units≈kg | 9.17 | 14.1 | 19.3 |
| Normal size b | 10 ×11 | 10 ×13 | 10 ×16 | |
|---|---|---|---|---|
| b | min | 9.964 | 9.964 | 9.964 |
| k | max=nominal size(h12) | 11 | 13 | 16 |
| k | min | 10.82 | 12.82 | 15.82 |
| d 1 | 28 | 32 | 45 | |
| L | ≈ | 27.35 | 31.43 | 43.08 |
| per 1000 units≈kg | 17.6 | 24.1 | 39.9 |
Materials
- Woodruff keys are supplied in key steel; the collected table tabulates geometry and mass only, so grade selection and hardness certificates are quoted per RFQ against your drawing
Ordering & documentation
Documents
Shipments are backed by Mill Test Certificate (MTC), Dimensional Report, Salt Spray Test Report on request, with full batch traceability from raw material to finished product. Quality management follows the owner-confirmed compliance list: ISO 9001:2015, RoHS, REACH. Exact document sets are confirmed on the order.
Quotation
- The fastener family (DIN 6888 Woodruff Keys) plus the standard designation from your drawing — DIN / ISO / JIS / ASTM / ANSI, or a drawing for custom parts.
- Size (diameter and length), thread type (metric or inch), property class or grade, and coating or finish.
- Quantity per size and your target delivery date.
- Destination country, and any required documents (for example a mill test certificate) so the quote includes them.
Sample & supply
Minimum order quantity is 10,000 pieces. Stock items run 3–7 days. Quantities or variants outside the standard range are confirmed at quotation.
Storage & shipping
Parts are packed for export and shipped factory-direct to buyers in Europe, Asia, the Americas and the Middle East. Store fasteners dry and protected until installation, and keep coated parts in their packaging until use; specific packing and preservation requirements can be stated on the order and confirmed at quotation.
Frequently asked questions
How do I read a woodruff key designation like 6 x 10?
The first number is the key width b (here 6 mm) and the second is the hub diameter d 1 (here 10 mm) — the diameter of the full circle from which the semi-circular key is cut, which also sets the depth of the milling cut in your shaft. From the table, a 6 x 10 key is 9.85 to 10 mm tall, roughly 24.5 mm along the arc and about 8.64 kg per 1000 pieces. The hub diameter matters when you specify the cutter: the woodruff cutter must match d 1, so pick the designation from your drawing and order the matching cutter size, not the other way round.
When would I choose a woodruff key over the parallel keys on the DIN 6885 page?
Woodruff keys earn their place on tapered shaft ends (mill arbors, pulleys, automotive crankshafts): the deep semicircular pocket lets the key pivot slightly to self-align with the hub keyway as it is assembled, which parallel keys cannot do, and the deeper shaft engagement resists the rolling forces on a taper. The trade-offs are visible in the two tables: the deep pocket weakens the shaft section compared with the shallow DIN 6885 keyway, and each woodruff size needs its own cutter, where a parallel keyway is one universal milling pass. So use DIN 6885 for plain cylindrical transmission shafts and DIN 6888 where a taper or self-alignment is involved — and quote from whichever table matches your drawing.
Related knowledge
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- Screw Family Selection by Base Material: Wood, Machine and Self-Tapping Threads, Engagement and Coating
- Hex Bolts vs Socket Head Cap Screws: What the Evidence Settles on Strength, Clearance and Cost
Request a Quote
Get factory-direct pricing from the manufacturer.
What to include in your inquiry
- ✓ Standard and property class (e.g. DIN 912, ISO 4762, class 8.8) — or a drawing for custom parts.
- ✓ Sizes, lengths and thread type (metric or inch).
- ✓ Quantity per size and your target delivery date.
- ✓ Destination country, plus any coating or finish requirement.
- ✓ Any documents you need with the shipment (e.g. mill test certificate) so the quote includes them.
- ✓ Your inquiry goes straight to the factory team by email and gets a reply within 24 hours.
- ✓ Factory-direct pricing
- ✓ Standard and custom specifications
- ✓ Factory-direct export to buyers in Europe, Asia, the Americas and the Middle East
- ✓ Full fastener family support