Socket Head Shoulder Cap Screw

Socket Head Shoulder Cap Screw Fasteners

Precision Alignment, Strength, and Versatile Performance

Socket head shoulder cap screws, also known as shoulder bolts or stripper bolts, are specialized fasteners engineered for applications that demand precision alignment, high strength, and long-term durability. Distinguished by a smooth, cylindrical shoulder beneath the head, these fasteners are designed to handle both shear and axial loads while maintaining accurate positioning between components. The internal hex (Allen) socket head allows for secure torque application and easy installation in tight or recessed spaces.

Function and Use

Load Control, Pivoting, and Alignment

The primary function of a socket head shoulder cap screw is to provide a stable, repeatable connection where controlled movement, spacing, or alignment is required. The unthreaded shoulder acts as a precision bearing surface, making these screws ideal for pivot points, sliding mechanisms, rollers, linkages, and guides. Because the load is carried on the shoulder rather than the threads, these fasteners deliver improved wear resistance and consistent mechanical performance in both static and dynamic applications.

Specifications and Material Options

Engineered for Exact Fit and Performance

Socket head shoulder cap screws are manufactured from alloy steel, stainless steel, and carbon steel, offering a range of strength and corrosion-resistance options. Key specifications include shoulder diameter, shoulder length, thread size, and overall length—each critical to achieving proper fit and function. Tight shoulder tolerances ensure accurate alignment and reduced play in precision assemblies. These fasteners are available in both fractional (inch) and metric sizes to meet global application requirements.

Plating and Finish Options

Corrosion Protection and Enhanced Durability

Common finishes include zinc plating for general corrosion resistance, black oxide for dimensional stability and a clean appearance, nickel plating for higher corrosion protection, and cadmium plating for specialized aerospace applications. Each finish is selected based on environmental exposure and performance needs.

Industries and Applications

Trusted Across High-Precision Markets

Socket head shoulder cap screws are widely used in aerospace, automotive, robotics, automation, industrial machinery, and manufacturing. Their ability to maintain alignment, manage loads, and support motion makes them an essential fastener for precision-engineered systems where reliability and accuracy are non-negotiable.