S-91247A531 1"-14 x 4 1/2" ASME B18.2.1, SAE J429 Medium-Strength Grade 5 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 120,000 psi ensures reliable performance in high-stress applications, reducing the risk of fastener failure.
• Superior corrosion resistance from zinc plating extends service life in harsh industrial environments, minimizing maintenance needs.
• Precision Class 2A thread fit with extra fine 1"-14 spacing provides secure, vibration-resistant connections for critical assemblies.
• Grade 5 strength classification and Rockwell C25 hardness offer dependable durability for heavy-duty mechanical and structural uses.
• Partially threaded design allows for optimal clamping force distribution, enhancing joint integrity in varied material thicknesses.
• External hex drive and hex head enable easy installation with standard tools, improving assembly efficiency.
• Compliance with ASME B18.2.1 and SAE J429 ensures consistent quality and interchangeability in regulated industries.

Professional Applications & Engineering Value

This Grade 5 hex head screw is engineered to address common industrial challenges, such as vibration loosening and corrosion-induced degradation. The zinc plated steel construction provides a protective barrier against moisture and chemicals, crucial for outdoor machinery, automotive frames, and construction equipment. Its extra fine thread spacing (1"-14) and Class 2A fit deliver superior grip and resistance to dynamic loads, making it ideal for precision assemblies in aerospace, heavy machinery, and structural frameworks. The partially threaded shank design concentrates clamping force where needed, preventing joint slippage in multi-material applications. By integrating high tensile strength and standardized dimensions, this fastener reduces downtime and ensures long-term reliability in demanding environments.

Specification Summary & Compliance

This fastener meets Class 2A thread fit tolerances per UNS standards, with a thread size of 1"-14 extra fine and right-hand threading. It conforms to ASME B18.2.1 and SAE J429 specifications for dimensional accuracy and performance. Additionally, it is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and material restrictions are met for global industrial use.