This page covers M3 SEMS Screws with Captive Conical Spring Washers to DIN 6900-5 Z9 and DIN 6908: the full dimensional row, hole and tool sizes, proof-load data and typical applications. All values are taken from the governing standards (DIN 6900-5 Z9 and DIN 6908 together with ISO 273, ISO 724 and ISO 898-1 where applicable).
M3 Dimensional Row (DIN 6900-5 Z9 and DIN 6908)
| Thread size | Pitch (mm) | Washer inside diameter (mm) | Washer outside diameter (mm) | Washer thickness (mm) | Material options | Reference standard |
|---|---|---|---|---|---|---|
| M3 | 0.5 | 2.75~2.85 | 6.64~7.0 | 0.6 | steel or A2 stainless | DIN 6900-5 Z9 and DIN 6908 |
Spanner & Drive for M3 SEMS Screws with Captive Conical Spring Washers
Drive geometry for M3 SEMS Screws with Captive Conical Spring Washers is given by the row above; match the tool to the listed values.
Hole Sizes for M3
| Coarse-thread pitch (ISO 724) | 0.5 mm |
|---|---|
| Through-hole / clearance (ISO 273 medium) | 3.4 mm |
| Tapping drill, coarse thread | 2.5 mm |
Tightening Torque for M3
| Class 8.8 (dry, ~µ 0.125) | ≈ 1.3 Nm |
|---|---|
| Class 10.9 (dry, ~µ 0.125) | ≈ Nm |
| Class 12.9 (dry, ~µ 0.125) | ≈ 2.2 Nm |
Indicative dry-joint values. Lubrication can lower the required torque by 15–25%. Always confirm against the joint design, especially when going up a strength class.
Proof Load & Strength for M3
| Tensile stress area As (ISO 724) | 5 mm² |
|---|---|
| Proof load, class 8.8 | 2.9 kN |
| Proof load, class 12.9 | 4.9 kN |
| Min. ultimate tensile load, class 8.8 | 4 kN |
Proof load = tensile stress area × the proof stress Sp of the class, per ISO 898-1 — Sp is a lower figure than the yield stress Rp0.2 and the two are not interchangeable. The stress area is computed from this size's own diameter and pitch, so a fine-pitch designation gives the fine-pitch figure. Design the joint so the working preload stays below the proof load of the class selected.
Installation Tips for M3 SEMS Screws with Captive Conical Spring Washers
- Pozidriv (PZ) drivers ride out of Phillips (PH) recesses and vice versa — confirm the recess marking on the head before assembly.
- For automated assembly, an ACR (Anti-Cam-Out Ribs) or torx-equivalent driver gives noticeably longer bit life than plain PH.
- At M3 the joint is sensitive to over-torque — use a torque-limiting driver and check the head doesn't bury into a softer counterpart.
Mating Parts for M3
For M3, pair with a M3 hex nut (ISO 4032 / DIN 934) and, where used, a M3 flat washer (ISO 7089 / DIN 125A) under the head and under the nut.
Custom manufacturing · Made to drawing
Need SEMS screws with captive conical spring washers in a size this table does not list?
This page covers M3 SEMS screws with captive conical spring washers. Thread size and pitch, length, property class, drive form, head geometry and head marking are all specifiable — the standard part is where it starts, not where it stops. Made by cold heading or warm forging.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
