DIN 470 Sealing Discs
DIN 470 spherical sealing discs — nominal diameters M3 to (M32), the dish-faced disc with a sphere-radius seat that seals and aligns on a mating concave face, with the collected bore/thickness/sphere-radius ladder and kg/1000 figures.
Last updated: 2026-11
Specifications
DIN 470 is the spherical-side sealing disc: a dished washer whose seat is ground to a sphere radius (the SR row runs 3 mm at M3 up to 45 mm at (M32)) so it rocks into a mating concave face and seals a fluid or grease passage around a bolt or fitting — the classic pairing is with a correspondingly chamfered or dished counterpart in hydraulic, lubrication and plumbing assemblies. The collected ladder runs M3 → (M32) with the parenthesised (M30) marking the source's non-preferred size, each size carrying bore min/max (e.g. M12: 11.945–12.055 mm), disc thickness H (1.2 → 4.95 mm), sphere radius, sealing-lip height h with its own tolerance split, and a kg/1000 pcs mass (0.047 → 13.2 kg). Read the bore tolerance for the clearance fit on the fastener, and the SR row against the mating seat — the two sphere radii must agree for the disc to seat full-face. Material, hardness and finish are not tabulated by the collected specification — per RFQ (sealing duty usually fixes the material, so name the medium and temperature at quotation).
| Standard | DIN 470 — sealing discs (spherical seat) |
|---|---|
| Size range | Nominal diameters M3 – (M32), (M30) parenthesised non-preferred per the source notation |
| Bore diameter | d: min/max per size (e.g. M12: 11.945 – 12.055 mm) |
| Disc thickness | H: 1.2 – 4.95 mm across the ladder |
| Sphere radius | SR: 3 – 45 mm, mating-seat dimension per size |
| Sealing lip | h: Nominal Size / max / min per size (0.8 – 2 mm nominal) |
| Weight | kg/1000 pcs column carried verbatim from the source (0.047 → 13.2) |
| Material / finish | Not tabulated by the collected specification — per RFQ |
| Nominal Diameter d | M3 | M4 | M5 | M6 |
|---|---|---|---|---|
| d — max | 3.03 | 4.0375 | 5.0375 | 6.0375 |
| min | 2.97 | 3.9625 | 4.9625 | 5.9625 |
| H | 1.2 | 1.34 | 1.35 | 1.67 |
| SR | 3 | 4 | 6 | 7 |
| h — Nominal Size | 0.8 | 0.8 | 0.8 | 1 |
| max | 0.95 | 0.95 | 0.95 | 1.15 |
| min | 0.65 | 0.65 | 0.65 | 0.85 |
| per 1000 units≈kg — ≈ | 0.047 | 0.084 | 0.132 | 0.236 |
| Nominal Diameter d | M8 | M10 | M12 |
|---|---|---|---|
| d — max | 8.045 | 10.045 | 12.055 |
| min | 7.955 | 9.955 | 11.945 |
| H | 1.94 | 2.67 | 2.77 |
| SR | 9 | 12 | 16 |
| h — Nominal Size | 1 | 1.6 | 1.6 |
| max | 1.15 | 1.75 | 1.75 |
| min | 0.85 | 1.45 | 1.45 |
| per 1000 units≈kg — ≈ | 0.517 | 1.05 | 1.49 |
| Nominal Diameter d | M14 | M16 | M18 |
|---|---|---|---|
| d — max | 14.055 | 16.055 | 18.055 |
| min | 13.945 | 15.945 | 17.945 |
| H | 2.94 | 3.11 | 3.28 |
| SR | 19 | 22 | 25 |
| h — Nominal Size | 1.6 | 1.6 | 1.6 |
| max | 1.75 | 1.75 | 1.75 |
| min | 1.45 | 1.45 | 1.45 |
| per 1000 units≈kg — ≈ | 2.02 | 2.63 | 3.35 |
| Nominal Diameter d | M20 | M22 | M25 |
|---|---|---|---|
| d — max | 20.065 | 22.065 | 25.065 |
| min | 19.935 | 21.935 | 24.935 |
| H | 3.45 | 4.09 | 4.38 |
| SR | 28 | 30 | 34 |
| h — Nominal Size | 1.6 | 2 | 2 |
| max | 1.75 | 2.15 | 2.15 |
| min | 1.45 | 1.85 | 1.85 |
| per 1000 units≈kg — ≈ | 4.12 | 7.1 | 8.98 |
| Nominal Diameter d | M28 | M(30) | M32 |
|---|---|---|---|
| d — max | 28.065 | 30.065 | 32.08 |
| min | 27.935 | 29.935 | 31.92 |
| H | 4.53 | 4.77 | 4.95 |
| SR | 40 | 42 | 45 |
| h — Nominal Size | 2 | 2 | 2 |
| max | 2.15 | 2.15 | 2.15 |
| min | 1.85 | 1.85 | 1.85 |
| per 1000 units≈kg — ≈ | 11.1 | 12.6 | 13.2 |
| Nominal Diameter d | M(34) | M36 | M(38) |
|---|---|---|---|
| d — max | 34.08 | 36.08 | 38.08 |
| min | 33.92 | 35.92 | 37.92 |
| H | 5.11 | 5.36 | 5.6 |
| SR | 48 | 50 | 52 |
| h — Nominal Size | 2 | 2 | 2 |
| max | 2.15 | 2.15 | 2.15 |
| min | 1.85 | 1.85 | 1.85 |
| per 1000 units≈kg — ≈ | 14.8 | 16.7 | 19.7 |
| Nominal Diameter d | M40 | M(42) | M45 |
|---|---|---|---|
| d — max | 40.08 | 42.08 | 45.08 |
| min | 39.92 | 41.92 | 44.92 |
| H | 5.7 | 5.8 | 6.15 |
| SR | 56 | 60 | 63 |
| h — Nominal Size | 2 | 2 | 2 |
| max | 2.15 | 2.15 | 2.15 |
| min | 1.85 | 1.85 | 1.85 |
| per 1000 units≈kg — ≈ | 20.5 | 22.6 | 26.1 |
| Nominal Diameter d | M(48) | M50 | M(52) |
|---|---|---|---|
| d — max | 48.08 | 50.08 | 52.095 |
| min | 47.92 | 49.92 | 51.905 |
| H | 6.38 | 6.62 | 6.66 |
| SR | 68 | 70 | 75 |
| h — Nominal Size | 2 | 2 | 2 |
| max | 2.15 | 2.15 | 2.15 |
| min | 1.85 | 1.85 | 1.85 |
| per 1000 units≈kg — ≈ | 29.5 | 32.1 | 34.5 |
- Row 8 (per 1000 units≈kg — ≈): The mass row label prints a stray "≈" sub-cell ("per 1000 units≈kg — ≈") — carried verbatim from the source, not merged into the label.
| Nominal Diameter d | M56 | M(60) | M63 |
|---|---|---|---|
| d — max | 56.095 | 60.095 | 63.095 |
| min | 55.905 | 59.905 | 62.905 |
| H | 7.06 | 7.47 | 7.7 |
| SR | 80 | 85 | 90 |
| h — Nominal Size | 2 | 2 | 2 |
| max | 2.15 | 2.15 | 2.15 |
| min | 1.85 | 1.85 | 1.85 |
| per 1000 units≈kg — ≈ | 40.2 | 46.3 | 50.9 |
| Nominal Diameter d | M80 | M100 | M125 |
|---|---|---|---|
| d — max | 80.095 | 100.11 | 125.125 |
| min | 79.905 | 99.89 | 124.875 |
| H | 10.41 | 12.23 | 14.2 |
| SR | 112 | 140 | 180 |
| h — Nominal Size | 3 | 3 | 3 |
| max | 3.15 | 3.15 | 3.15 |
| min | 2.85 | 2.85 | 2.85 |
| per 1000 units≈kg — ≈ | 134 | 204 | 313 |
Materials
- Material specified per RFQ — sealing discs are commonly soft steel or copper alloys depending on the sealed medium; state the medium, pressure and temperature at quotation
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 470 Sealing Discs) 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
What does the SR sphere radius do, and why does it grow so fast with size?
The disc's sealing face is not flat — it is a shallow spherical cap, and the SR row is that sphere's radius. It exists so the disc can misalign slightly with its mating concave seat and still touch full-face: bolt head tilt, part machining variation and assembly skew all eat a few degrees, and a spherical seat absorbs them while a flat washer would gasket on an edge and leak. The radius tracks the disc diameter rather than staying proportional to the bore — 3 mm at M3 but already 16 mm at M12 and 45 mm at (M32) — because the cap's sagitta (how dished it is) is what the designer fixed, and a bigger disc needs a proportionally bigger sphere to keep the same dish depth. Order by your mating part's seat radius: the two SR figures must match, and the collected table gives you the disc side of that pair. Material selection stays per RFQ — the source tabulates geometry only.
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