S-91257A973 1"-8 x 7" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional strength and reliability with Grade 8 classification, ensuring consistent performance under high-stress conditions and a tensile strength of 150,000 psi for demanding applications.
• Superior corrosion resistance provided by the zinc yellow-chromate plating, extending service life in harsh industrial environments and reducing maintenance needs.
• High hardness and durability with Rockwell C33 hardness, offering excellent wear resistance and minimizing deformation during installation and use.
• Easy installation and removal thanks to the external hex drive and coarse UNC thread design, allowing for quick assembly with standard tools and reducing labor time.
• Precise fit and reduced vibration loosening due to the Class 2A thread fit and partially threaded design, ensuring secure fastening in heavy machinery and structural applications.
• Compliance with industry standards including ASME B18.2.1 and SAE J429, guaranteeing quality, interchangeability, and safety for professional engineering projects.
• Environmental and regulatory safety with RoHS 3 and REACH compliance, making these screws suitable for global supply chains and eco-conscious industrial operations.

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 frameworks, and automotive systems. The steel material combined with zinc yellow-chromate plating provides robust protection against rust and chemical exposure, ideal for outdoor or corrosive environments. Its 1"-8 UNC coarse thread and partially threaded design enhance grip and load distribution, reducing the risk of joint failure under dynamic stresses. By meeting ASME B18.2.1 specifications, it ensures dimensional accuracy and reliability, making it a trusted choice for engineers seeking high-strength fasteners that minimize downtime and maintenance costs in applications like structural bracing, equipment mounts, and industrial vehicles.

Specification Summary & Compliance

This fastener adheres to precise dimensional standards, including Class 2A thread fit for consistent engagement and UNC coarse threading with a size of 1"-8. It complies with ASME B18.2.1 and SAE J429 manufacturing specifications, ensuring high-quality production. Additionally, it meets environmental regulations such as RoHS 3 (2015/863/EU) and REACH (EC 1907/2006), confirming its safety for use in regulated industries without hazardous substances.