S-91286A123 1/4"-20 x 2 1/2" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 150,000 psi ensures reliable performance in high-stress industrial applications, reducing the risk of fastener failure.
• Superior corrosion resistance from the zinc-flake coating extends service life in harsh environments, minimizing maintenance and replacement costs.
• High hardness (Rockwell C33) provides excellent wear resistance, maintaining thread integrity and drive engagement over repeated use.
• Coarse UNC threads enable quick and secure installation, reducing assembly time and improving efficiency in production lines.
• Partial threading design offers optimal grip and clamping force for specific joint requirements, enhancing structural stability.
• External hex drive allows for high-torque application with standard tools, ensuring tight fastening and ease of maintenance.
• Compliance with industry standards including ASME B18.2.1 and SAE J429 guarantees consistent quality and interoperability in mechanical assemblies.

Professional Applications & Engineering Value

This Grade 8 hex head screw is engineered to address critical challenges in heavy-duty applications, such as machinery, construction, and automotive assemblies, where high tensile strength and durability are paramount. The zinc-flake coated steel construction combats corrosion in demanding environments, reducing downtime and lifecycle costs. With a coarse UNC thread and partial threading, it ensures rapid installation and secure fastening in materials prone to vibration, preventing loosening. Its external hex drive facilitates easy torque application, making it ideal for maintenance and repair tasks. By meeting rigorous standards like ASME B18.2.1, this fastener delivers reliable performance, enhancing safety and efficiency in industrial settings where precision and compliance are essential.

Specification Summary & Compliance

This product adheres to precise dimensional tolerances, including a Class 2A thread fit for consistent engagement and interchangeability. It conforms to ASME B18.2.1 and SAE J429 specifications for mechanical properties and design. Additionally, it is 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.