Metric Socket Shoulder Screws
Metric socket shoulder screws are precision fasteners built around a smooth cylindrical shoulder that sits between the head and the threaded end. That shoulder provides a bearing surface for rotating, sliding, and pivoting components. Also called shoulder bolts or stripper bolts, they're used across industrial machinery, automation, tooling, and more. Metric socket shoulder screws are a standard solution wherever precise alignment and controlled movement are required.
Empire Bolt & Screw is a national distributor of metric and standard socket shoulder screws. Contact us today to learn more about our supply solutions, or request a quote to get started on a metric socket shoulder screw order in bulk or custom quantities.
Empire Bolt & Screw is a national distributor of metric and standard socket shoulder screws. Contact us today to learn more about our supply solutions, or request a quote to get started on a metric socket shoulder screw order in bulk or custom quantities.
What Are Metric Socket Shoulder Screws?
A metric socket shoulder screw has three sections: the head, the shoulder, and the threaded end.The head accepts an internal hex key for installation. The shoulder is the precision-ground, unthreaded shank that is longer than the threaded portion and intentionally larger in diameter. The threaded end pulls the screw into the tapped hole, while the shoulder remains free to function as a bearing surface. Bearings, bushings, pulleys, and linkages all ride on the shoulder, not the threads.
Shoulder Diameter vs. Thread Diameter
The shoulder diameter is always larger than the thread diameter. These dimensions follow a defined relationship under metric standards. An M6-threaded shoulder screw, for example, may have an 8mm or 10mm shoulder depending on the series. This is important to note when designing clearance holes or selecting mating components.Metric Sizing Standards
Metric shoulder screws conform to ISO 7379 and DIN 9841, which govern shoulder diameter, thread pitch, head geometry, and tolerance class. Shoulder tolerances are typically h8 or h11. These standards are not interchangeable with inch-series shoulder screws.Internal Hex Drive
The socket drive allows higher installation torque than slotted or Phillips styles, with a compact head profile that works in tight or recessed assemblies. It's also more consistent in production environments.Key Features and Benefits
- Precision bearing surface: Ground shoulder provides accurate, concentric support for rotating and sliding components
- High strength: Class 12.9 alloy steel handles high tensile loads and dynamic cyclic forces
- Wear resistance: Smooth shoulder finish reduces friction
- Tight tolerances: Precision ISO 7379 shoulder tolerances
- Compact hex drive: Low-profile head
- Accurate spacing: Shoulder length controls component positioning
- Consistent performance: Repeatable across production runs with standard metric sizing
Common Applications for Metric Shoulder Screws
Metric shoulder screws are used wherever a component needs to rotate, slide, pivot, or be accurately positioned relative to a fixed point. Common functions include pivot pins, axles, guide shafts, and rotating element supports.Typical Industries and Equipment that Use Metric Shoulder Screws
- Industrial machinery
- Robotics and automation
- Bearings and pulleys
- Conveyor equipment
- Tool and die
- Packaging machinery
- Electronics assemblies
- Medical equipment
- Aerospace and defense
Available Materials and Finishes for Metric Socket Shoulder Screws
| Material | Strength | Corrosion Resistance | Available Finishes | Best For |
|---|---|---|---|---|
| Alloy Steel, Class 12.9 | Highest | Low | Black Oxide, Zinc Plated | High-load mechanical, die sets, dynamic applications |
| 18-8 Stainless Steel | Moderate | Good | Plain (natural finish) | General industrial, food processing, mild chemical exposure |
| 316 Stainless Steel | Moderate | Excellent | Plain (natural finish) | Marine, chemical processing, medical, harsh environments |
Choosing between alloy steel and stainless: If strength is the primary concern and the environment is controlled, Class 12.9 alloy steel is the standard choice. When corrosion resistance is required, 18-8 handles most general applications. Step up to 316 for saltwater, chemical exposure, or medical use.
Why Buy Metric Socket Shoulder Screws from Empire Bolt?
Empire Bolt & Screw has supplied precision fasteners to manufacturers since 1972. We stock common metric shoulder screw sizes and have the sourcing capability to find what isn't on the shelf, including non-standard shoulder lengths, specialty materials, and custom finishes.What sets us apart:
- In-house Mechanical Engineer: Available for application support and material selection
- Quality Assurance Laboratory: On-site dimensional inspection by certified QC Technicians
- OEM and custom sourcing: Non-standard sizes, materials, and finishes that meet your specifications
- Inventory management programs: VMI, Kanban, and Just-in-Time programs to keep your line running
- Fast turnaround: Stock items ship quickly; scheduled delivery available for ongoing OEM requirements
- Broad industry experience: Industrial machinery, robotics, medical, aerospace, electronics, and more
Contact Us to Learn How Empire Can Be Your Metric Socket Shoulder Screw Supplier
Ready to source metric socket shoulder screws? Request a quote or contact our team today to get started. Looking for other socket fasteners? Explore our full selection of socket screws, including socket head cap screws, flat head socket screws, and button head socket screws.
