S-91268A280 1/2"-20 x 2 1/4" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capability with 150,000 psi tensile strength for reliable performance in high-stress applications
• Superior wear resistance due to Rockwell C33 hardness, ensuring long service life and reduced replacement frequency
• Precise thread engagement with Class 2A fit and UNF fine thread design for secure, vibration-resistant connections
• Full-length threading provides consistent clamping force along the entire 2 1/4" length for uniform load distribution
• Heavy-duty Grade 8 classification guarantees consistent mechanical properties for critical industrial assemblies
• External hex drive compatibility allows for high-torque installation using standard tools without stripping risks
• Regulatory compliance assurance meeting ASME, SAE, RoHS 3 and REACH standards for global project suitability

Professional Applications & Engineering Value

Engineered for demanding industrial environments, this Grade 8 hex head screw delivers exceptional performance where failure isn't an option. The combination of high-strength steel material and UNF fine threading addresses critical challenges in heavy machinery, structural steel connections, and high-vibration equipment. The 1/2"-20 thread configuration with Class 2A tolerance ensures precise mating with corresponding nuts and tapped holes, eliminating play while maintaining disassembly capability. Fully threaded design maximizes surface contact area, distributing stress evenly to prevent localized fatigue failures. Ideal for construction equipment, automotive frames, and industrial manufacturing applications where 150,000 psi tensile strength and Rockwell C33 hardness provide the margin of safety needed for critical load-bearing assemblies.

Specification Summary & Compliance

This hex head screw features precision 1/2"-20 UNF threads with Class 2A thread fit per inch system requirements, ensuring interchangeability with standard components. Manufacturing complies with ASME B18.2.1 and SAE J429 Grade 8 specifications for dimensional accuracy and mechanical properties. The fastener is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, containing no restricted substances above threshold limits. All dimensional and performance characteristics are verified to meet industrial standards for high-strength bolting applications.