Product Description
¼"-20 UNC High Tensile Socket Shoulder Bolts – 5/16" Shoulder
High tensile steel socket shoulder bolts with a ¼"-20 UNC threaded end and a 5/16" nominal diameter shoulder. The smooth, unthreaded shoulder provides a bearing or locating surface for moving components, while the threaded end secures the bolt into a matching tapped hole.
Supplied with a self colour finish and an internal hexagon socket for installation using a 5/32" Allen key. Suitable for machinery, tooling, pivots and guide assemblies.
Specifications
| Feature | Specification |
|---|---|
| Fastener type | Socket head shoulder bolt / shoulder screw |
| Material | High tensile alloy steel |
| Finish | Self colour – unplated |
| Dimensional standard | ASME/ANSI B18.3 |
| Material specification | ASTM A574 |
| Thread size | ¼"-20 UNC |
| Threads per inch | 20 TPI |
| Nominal shoulder diameter | 5/16" (7.9375mm nominal) |
| Shoulder diameter limits | 0.3085"–0.3105" (approximately 7.836–7.887mm) |
| Head diameter limits | 0.419"–0.438" (approximately 10.64–11.13mm) |
| Head height limits | 0.209"–0.219" (approximately 5.31–5.56mm) |
| Hexagon socket / Allen key size | 5/32" |
| Length measurement | Shoulder length only, measured from beneath the head to the end of the shoulder, excluding the threaded end |
Understanding the Size
The ¼" size refers to the threaded end. The larger 5/16" dimension is the nominal shoulder diameter. The shoulder is manufactured slightly below its nominal diameter, as shown in the dimensional limits above.
The selected length is the length of the unthreaded shoulder. It does not include the head or the threaded section.
Key Features
- Smooth shoulder for locating components or supporting movement.
- ¼"-20 UNC thread for matching imperial tapped holes.
- Internal hexagon socket for installation with a 5/32" Allen key.
- High tensile alloy steel construction with a self colour finish.
Typical Applications
Used in pivot mechanisms, pulley assemblies, guides, tooling and machinery where a smooth shoulder is required between the head and the threaded fixing point.
Ordering
Select the required shoulder length and pack quantity from the available options. Check the shoulder diameter, shoulder length and thread size against your assembly before ordering.
