Socket Head Cap vs. Wafer Head
Comparing 2 standards across 11 specifications. 11 key differences identified.
Socket Head Cap Screws (SHCS, standardized under DIN 912 and ISO 4762) feature a compact cylindrical head whose height is approximately equal to the screw shank diameter, housing a deep internal hexagonal (Allen) or Torx socket. Engineered for high-tensile alloy steel applications, it allows high-torque fastening inside tight, counterbored machine recesses.
Wafer Head screws (Modified Truss / K-Lath / Framing Screws) feature an ultra-flat, razor-thin head with an integrated wide circular clamping rim and a flat underside. Engineered with a self-drilling TEK point or sharp piercing tip, they are standard in light-gauge steel stud framing, metal lath attachment, and drywall partition construction.
Specification Comparison Table
11 Parameters| Parameter / Spec | ||
|---|---|---|
|
Standard Specifications
|
ISO 4762 / DIN 912 / ASME B18.3 | ASTM C1002 (Steel studs) / ASTM C954 / DIN 7504-M |
|
Primary Applications
|
Industrial tooling, machine tools, 3D printer extruders, automotive cylinder heads | Steel stud framing, stucco metal lath, HVAC ductwork, M.2 SSD hold-down screws |
|
Head Geometry
|
Tall cylindrical head with knurled or smooth outer diameter | — |
|
Head Height Ratio
|
Head Height ≈ Screw Major Diameter (H ≈ D) | — |
|
Head Outer Diameter Ratio
|
Head Diameter ≈ 1.5 × Screw Diameter (D_k ≈ 1.5D) | — |
|
Recessed Drive Type
|
Internal Hexagon (Allen) or Hexalobular (Torx) | — |
|
Standard Steel Property Class
|
High-tensile Class 12.9 (1,220 MPa) / Class 10.9 / Class 8.8 / A2-70 Stainless | — |
|
Head Thickness
|
— | Ultra-thin low profile (~1.0 mm to 1.5 mm thick) |
|
Head Outer Diameter
|
— | Wide circular flange (10.0 mm to 11.5 mm on #8 screws) |
|
Point Types
|
— | Self-Drilling TEK Point (#2/#3 drill point) or Sharp Piercing Point (Type S) |
|
Common Drive Recess
|
— | Phillips #2 / Square #2 |