S-91257A650 3/8"-16 x 7" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Maximum Load-Bearing Capacity: Grade 8 classification and 150,000 psi tensile strength ensure reliable performance in high-stress industrial environments.
• Superior Corrosion Resistance: Zinc yellow-chromate plating provides excellent protection against rust and environmental degradation, extending service life.
• High Mechanical Durability: Rockwell C33 hardness offers exceptional wear resistance and maintains structural integrity under repeated use.
• Optimized Thread Engagement: UNC coarse thread design with Class 2A fit enables faster assembly and secure fastening in various materials.
• Enhanced Torque Application: External hex drive with 9/16" head width allows for high-torque installation using standard tools.
• Versatile Partial Threading: 1 1/4" minimum thread length provides both threaded engagement and smooth shank for precise clamping applications.
• Regulatory Compliance Assurance: Meets ASME B18.2.1 specifications and environmental standards including RoHS 3 and REACH for global acceptance.

Professional Applications & Engineering Value

Engineered for demanding industrial applications, these Grade 8 hex head screws deliver exceptional performance in construction, heavy machinery, and structural assemblies where high tensile strength is critical. The zinc yellow-chromate plating effectively combats corrosion in harsh environments, while the UNC coarse threads provide superior grip in both metal and composite materials. The partial threading design allows for precise load distribution, making these 7-inch hex screws ideal for applications requiring both clamping force and shear strength. Their external hex drive ensures compatibility with standard industrial tools, streamlining installation processes in manufacturing and maintenance operations.

Specification Summary & Compliance

This 3/8"-16 x 7" hex head screw features Class 2A thread fit tolerance for consistent engagement and meets ASME B18.2.1 manufacturing specifications. The fastener maintains UNC coarse thread standards with precise dimensional accuracy and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. Manufactured to SAE J429 Grade 8 requirements, it delivers guaranteed mechanical properties including 150,000 psi tensile strength and Rockwell C33 hardness for reliable performance in critical applications.