S-90044A266 5/16"-18 x 8 1/2" ASTM A574 Alloy Steel Socket Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 170,000 psi ensures reliable performance under high-stress conditions
• Superior corrosion resistance provided by black-oxide coating extends service life in demanding environments
• Precise Class 3A thread fit guarantees secure fastening with minimal vibration loosening
• Optimized partial threading design allows for focused engagement where maximum holding power is required
• Rockwell C37 hardness rating maintains structural integrity through repeated installation cycles
• Hex socket drive compatibility enables high-torque application with standard industrial tools
• Coarse UNC thread spacing facilitates quick assembly and disassembly in maintenance operations

Professional Applications & Engineering Value

Engineered for heavy-duty industrial applications, these black-oxide alloy steel socket head cap screws solve critical challenges in machinery assembly, automotive manufacturing, and equipment maintenance. The combination of 170,000 psi tensile strength and Rockwell C37 hardness ensures these fasteners withstand extreme mechanical stresses without deformation or failure. The 5/16"-18 UNC coarse thread configuration provides rapid installation in time-sensitive production environments, while the partial threading design concentrates engagement strength precisely where needed. The black-oxide surface treatment delivers reliable corrosion protection in environments exposed to moisture, chemicals, and industrial contaminants, making these screws ideal for outdoor equipment, manufacturing machinery, and automotive subsystems requiring durable, high-performance fastening solutions.

Specification Summary & Compliance

This 8 1/2" socket head cap screw features precise Class 3A thread fit with UNC coarse thread spacing and 1 1/8" minimum thread length. Manufactured to ASTM A574 specification for high-strength alloy steel socket head cap screws, ensuring consistent quality and performance. Fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, making them suitable for global industrial applications requiring strict regulatory adherence.