DIN 128A Spring Lock Washers, Type A
DIN 128A spring lock washers type A, sizes 2 to 36 — the helical spring washer with the adsorbing collar that stops sideways creep — with the full collected 20-size table: bore, collar diameter, section width, material thickness, free height and the source's reference mass per 1000 units.
Last updated: 2026-11
Specifications
DIN 128A is the type A spring lock washer: the standard helical coil that springs a bolted joint against rotation, plus a flat collar turned up on the outer edge. That collar is the working difference from DIN 127B — it seats against the bearing surface and stops the washer walking sideways under vibration, which is why type A shows up on machinery where the joint sees lateral movement as well as axial loosening torque. The collected table covers sizes 2 to 36 — 20 sizes — with bore d (min / max), the type-A collar outside diameter d c max, section width b, material thickness s, free height h, and the source's reference mass per 1000 units. Spring force, materials and finishes are not printed by the collected specification and stay per RFQ. For the heavy type B form without the collar see DIN 128B, and for the common non-collared helical washer see DIN 127 on this site.
| Standard | DIN 128 form A — helical spring lock washers with adsorbing collar |
|---|---|
| Series | 2 – 36 (20 sizes tabulated), matching nominal bolt diameters |
| Tabulated geometry | Per size: bore d (min / max), collar outside diameter d c (max), section width b (Nominal Size / max / min), thickness s (Nominal Size / max / min), free height h (min / max), reference mass per 1000 units ≈ kg |
| Function | Helical coil loads the joint axially against rotation; the outer collar resists sideways creep of the washer |
| Spring force / materials | Not tabulated by the collected specification — per RFQ (spring steel grade and finish per drawing callout) |
| Size | d — min | d — max | d c — max | b — Nominal Size | b — max | b — min | s — Nominal Size | s — max | s — min | h — min | h — max | per 1000 units ≈ kg |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2 | 2.1 | 2.4 | 4.4 | 0.9 | 1 | 0.8 | 0.5 | 0.6 | 0.4 | 0.7 | 0.9 | 0.035 |
| 2.5 | 2.6 | 2.9 | 5.1 | 1 | 1.1 | 0.9 | 0.6 | 0.7 | 0.5 | 0.9 | 1.1 | 0.055 |
| 3 | 3.1 | 3.4 | 6.2 | 1.3 | 1.4 | 1.2 | 0.7 | 0.8 | 0.6 | 1.1 | 1.3 | 0.09 |
| 3.5 | 3.6 | 3.9 | 6.7 | 1.3 | 1.4 | 1.2 | 0.7 | 0.8 | 0.6 | 1.1 | 1.3 | 0.1 |
| 4 | 4.1 | 4.4 | 7.6 | 1.5 | 1.6 | 1.4 | 0.8 | 0.9 | 0.7 | 1.2 | 1.4 | 0.15 |
| 5 | 5.1 | 5.4 | 9.2 | 1.8 | 1.9 | 1.7 | 1 | 1.1 | 0.9 | 1.5 | 1.7 | 0.3 |
| 6 | 6.1 | 6.5 | 11.8 | 2.5 | 2.65 | 2.35 | 1.3 | 1.4 | 1.2 | 2 | 2.2 | 0.7 |
| 7 | 7.1 | 7.5 | 12.8 | 2.5 | 2.65 | 2.35 | 1.3 | 1.4 | 1.2 | 2 | 2.2 | 0.75 |
| 8 | 8.1 | 8.5 | 14.8 | 3 | 3.15 | 2.85 | 1.6 | 1.7 | 1.5 | 2.45 | 2.75 | 1.3 |
| 10 | 10.2 | 10.7 | 18.1 | 3.5 | 3.7 | 3.3 | 1.8 | 1.9 | 1.7 | 2.85 | 3.15 | 2.1 |
| 12 | 12.2 | 12.7 | 21.1 | 4 | 4.2 | 3.8 | 2.1 | 2.25 | 1.95 | 3.35 | 3.65 | 3.2 |
| 14 | 14.2 | 14.7 | 24.1 | 4.5 | 4.7 | 4.3 | 2.4 | 2.55 | 2.25 | 3.9 | 4.3 | 4.8 |
| 16 | 16.2 | 17 | 27.4 | 5 | 5.2 | 4.8 | 2.8 | 2.95 | 2.65 | 4.5 | 5.1 | 7 |
| 18 | 18.2 | 19 | 29.4 | 5 | 5.2 | 4.8 | 2.8 | 2.95 | 2.65 | 4.5 | 5.1 | 7.8 |
| 20 | 20.2 | 21.2 | 33.6 | 6 | 6.2 | 5.8 | 3.2 | 3.4 | 3 | 5.1 | 5.9 | 12.2 |
| 22 | 22.5 | 23.5 | 35.9 | 6 | 6.2 | 5.8 | 3.2 | 3.4 | 3 | 5.1 | 5.9 | 13.3 |
| 24 | 24.5 | 25.5 | 40 | 7 | 7.25 | 6.75 | 4 | 4.2 | 3.8 | 6.5 | 7.5 | 21.5 |
| 27 | 27.5 | 28.5 | 43 | 7 | 7.25 | 6.75 | 4 | 4.2 | 3.8 | 6.5 | 7.5 | 23.7 |
| 30 | 30.5 | 31.7 | 48.2 | 8 | 8.25 | 7.75 | 6 | 6.2 | 5.8 | 9.5 | 10.5 | 42.5 |
| 36 | 36.5 | 37.7 | 58.2 | 10 | 10.25 | 9.75 | 6 | 6.2 | 5.8 | 10.3 | 11.3 | 68 |
Materials
- Material and finish specified per RFQ — spring performance depends on the tempered spring-steel grade; confirm 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 128A Spring Lock Washers, Type A) 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
When does the type A collar earn its place over a plain helical washer?
When the washer itself moves. A plain helical washer works by its cut ends biting and its coil loading the joint, but on a face that is not flat — or where the assembly flexes — the washer can creep off the bearing surface and the preload is gone. The DIN 128A collar is a shallow flange on the outer edge that traps the washer against the joint face, keeping the coil where it was installed. That is why type A is specified on machine tools, engines and vibrating frames where the extra collar costs little but the disassembly to re-torque costs a lot. On flat, rigid faces a DIN 127B washer does the same basic job more cheaply — check the two tables and match the bore to the bolt.
What is the MOQ and lead time for this washer type?
The minimum order quantity is 10,000 pieces. Stock items ship in 3–7 days; non-stock items are confirmed at quotation. Common sizes are widely stocked; confirm the exact schedule against quantity and size mix at quotation.
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