S-91257A698 7/16"-20 x 1 3/4" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional Load-Bearing Capacity: With a 150,000 psi tensile strength and Rockwell C33 hardness, this screw provides reliable performance in high-stress applications, reducing the risk of fastener failure.
• Superior Corrosion Resistance: The zinc yellow-chromate plating on steel offers enhanced protection against rust and environmental degradation, extending the service life of your assemblies.
• Precise Thread Engagement: UNF fine threading and Class 2A thread fit ensure tight, secure fastening with reduced likelihood of loosening under vibration.
• Optimized for Heavy-Duty Use: As a Grade 8 fastener, it meets rigorous standards for strength and durability, ideal for demanding industrial and mechanical applications.
• Easy Installation and Removal: The external hex drive and hex head design allow for straightforward torque application with standard tools, improving assembly efficiency.
• Regulatory Compliance Assurance: Compliant with ASME B18.2.1, RoHS 3, and REACH, ensuring safety, environmental standards, and global market acceptance.
• Versatile Thread Configuration: Partially threaded design with a 1 1/8" minimum thread length provides flexibility for applications requiring unthreaded shank sections.

Professional Applications & Engineering Value

This Grade 8 hex head screw is engineered to address critical challenges in heavy-duty industrial settings, such as machinery assembly, construction equipment, and automotive systems. The zinc yellow-chromate plated steel construction combats corrosion in harsh environments, while the 7/16"-20 UNF fine thread and Class 2A fit deliver precise, vibration-resistant connections. Its 150,000 psi tensile strength and Rockwell C33 hardness ensure it withstands extreme loads and impacts, minimizing maintenance needs. Ideal for applications requiring reliable fastening solutions under high stress, this screw enhances structural integrity and operational safety in sectors like manufacturing, transportation, and infrastructure.

Specification Summary & Compliance

This screw adheres to Class 2A thread fit tolerances and UNF fine thread standards, ensuring dimensional accuracy and compatibility. It is manufactured in compliance with ASME B18.2.1 and SAE J429 specifications, guaranteeing consistent quality and performance. Additionally, it meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming its safety and environmental responsibility for global industrial use.