S-94328A977 5/16"-18 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength (140,000 psi) ensures reliable performance in high-stress industrial applications, reducing the risk of fastener failure.
• Precision Class 3A thread fit provides superior engagement and vibration resistance, minimizing loosening in dynamic environments.
• Corrosion-resistant black oxide finish extends service life by protecting against rust and wear in harsh operating conditions.
• Low-profile socket head with knurled texture offers easy installation and removal while maintaining a sleek profile in compact assemblies.
• Hardened alloy steel construction (Rockwell C30) delivers excellent durability and resistance to deformation under heavy loads.
• Standard shoulder fit with precise diameter and length tolerances ensures accurate alignment and smooth rotation in pivoting or guiding applications.
• Compliance with RoHS 3 and REACH regulations guarantees environmental safety and meets global industry standards for hazardous substance restrictions.

Professional Applications & Engineering Value

This 5/16"-18 UNC shoulder screw is engineered to address critical challenges in machinery and equipment design. The alloy steel core, hardened to Rockwell C30, provides the necessary strength to withstand repetitive stress and shock loads in automated systems. The coarse thread spacing and Class 3A thread fit ensure quick assembly and secure fastening, reducing installation time while preventing thread stripping. The black oxide finish adds a layer of corrosion resistance, making it ideal for environments exposed to moisture or chemicals. Commonly used in pivoting mechanisms, bearing mounts, and precision guides, the low-profile socket head with knurling allows for tool-friendly access without protruding, maintaining clean lines in compact designs. Its right-hand thread and standardized shoulder dimensions facilitate seamless integration into existing industrial setups, enhancing operational reliability.

Specification Summary & Compliance

This shoulder screw adheres to UNC thread standards with a Class 3A thread fit for tight tolerances and optimal performance. Key dimensions include a thread size of 5/16"-18, shoulder diameter of 3/8" (tolerance: -0.004" to -0.002"), and shoulder length of 1 1/4" (tolerance: -0.005" to 0.005"). Manufactured from alloy steel with a black oxide finish, it meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliance, ensuring adherence to environmental and safety regulations for industrial use.