This page covers M4 Tri-Wing Pan-Head Machine Screws to Trade series (Tri-Wing pan-head screws): the full dimensional row, hole and tool sizes, proof-load data and typical applications. All values are taken from the governing standards (Trade series (Tri-Wing pan-head screws) together with ISO 273, ISO 724 and ISO 898-1 where applicable).
M4 Dimensional Row (Trade series (Tri-Wing pan-head screws))
| Thread size | Head diameter (mm) | Head height (mm) | Drive | Length range (mm) | Material / finish |
|---|---|---|---|---|---|
| M4 | 8.17 | 2.92 | W4 | 6~30 | A2 stainless / blackened / Nylok-coated |
Spanner & Drive for M4 Tri-Wing Pan-Head Machine Screws
Drive geometry for M4 Tri-Wing Pan-Head Machine Screws is given by the row above; match the tool to the listed values.
Hole Sizes for M4
| Coarse-thread pitch (ISO 724) | 0.7 mm |
|---|---|
| Through-hole / clearance (ISO 273 medium) | 4.5 mm |
| Tapping drill, coarse thread | 3.3 mm |
Tightening Torque for M4
| Class 8.8 (dry, ~µ 0.125) | ≈ 2.9 Nm |
|---|---|
| Class 10.9 (dry, ~µ 0.125) | ≈ Nm |
| Class 12.9 (dry, ~µ 0.125) | ≈ 5 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 M4
| Tensile stress area As (ISO 724) | 8.8 mm² |
|---|---|
| Proof load, class 8.8 | 5.1 kN |
| Proof load, class 12.9 | 8.5 kN |
| Min. ultimate tensile load, class 8.8 | 7 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.
M4 Tri-Wing Pan-Head Machine Screws Weight
A steel M4 tri-wing pan-head machine screws at the listed 630 mm length weighs approximately 62 g each — about 62 kg per 1,000 pieces. Stainless A2/A4 weighs roughly the same (density 7.9–8.0 g/cm³).
Actual weight varies slightly with head form, thread and finish; use this figure for freight estimation only.
Installation Tips for M4 Tri-Wing Pan-Head Machine Screws
- At M4 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 M4
For M4, pair with a M4 hex nut (ISO 4032 / DIN 934) and, where used, a M4 flat washer (ISO 7089 / DIN 125A) under the head and under the nut.
Custom manufacturing · Made to drawing
Need tri-wing pan-head machine screws in a size this table does not list?
This page covers M4 tri-wing pan-head machine screws. 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.
