S-91268A170 5/16"-18 x 1 1/2" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Maximum load-bearing capability with 150,000 psi tensile strength for critical structural applications
• Superior wear resistance due to Rockwell C33 hardness, extending service life in high-stress environments
• Reliable thread engagement with Class 2A thread fit ensuring consistent assembly performance
• Quick installation through coarse UNC threading and external hex drive design
• Full thread coverage along the 1-1/2" length for maximum grip and load distribution
• Heavy-duty construction using Grade 8 steel for demanding industrial applications
• Regulatory compliance with ASME B18.2.1 standards and environmental regulations including RoHS 3 and REACH

Professional Applications & Engineering Value

These Grade 8 hex head screws deliver exceptional engineering value in demanding industrial settings where fastener failure is not an option. The combination of 150,000 psi tensile strength and Rockwell C33 hardness provides critical protection against shear forces and vibrational loosening in heavy machinery, structural steel connections, and high-pressure equipment. The 5/16"-18 UNC coarse thread design ensures rapid installation while maintaining secure fastening, significantly reducing assembly time in production environments. The fully threaded configuration offers maximum clamping force distribution across the entire 1-1/2" length, making these steel fasteners ideal for applications requiring uniform stress distribution and vibration resistance in construction, manufacturing, and automotive industries.

Specification Summary & Compliance

This Grade 8 hex head screw features precise Class 2A thread fit tolerances with 5/16"-18 UNC coarse threading and right-hand thread direction. Manufactured to ASME B18.2.1 specifications where applicable under SAE J429 standards. The fastener demonstrates full compliance with RoHS 3 (2015/863/EU) regulations and REACH (EC 1907/2006) requirements, including the latest SVHC updates. With dimensions of 1-1/2" length, 1/2" head width, and 7/32" head height, these industrial-grade screws maintain consistent performance across demanding applications while meeting international quality and environmental standards.