S-91268A159 1/4"-20 x 4 1/2" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws
High-Strength Grade 8 Steel Hex Head Screws
Image may differ from product. See technical specification for details.
Basic Information
Head Parameters
Dimensions
Thread Parameters
Tip & Drive Parameters
Material & Strength
Temperature & Environment
- Fast delivery
- Enjoy discounts on bulk purchases
- Secure Payment
- Fast Global Shipping
Key Features & Benefits at a Glance
- Exceptional load-bearing capacity with 150,000 PSI tensile strength for reliable performance in high-stress applications
- Superior wear resistance due to Rockwell C33 hardness, ensuring long service life in demanding environments
- Secure fastening with coarse UNC threads that provide excellent grip and reduce cross-threading risks during installation
- Optimized partial threading design for precise clamping force distribution and vibration resistance
- Heavy-duty Grade 8 steel construction delivering consistent performance in industrial and mechanical applications
- External hex drive compatibility with standard tools for quick installation and removal
- Full regulatory compliance meeting RoHS 3 and REACH environmental standards for safe industrial use
Professional Applications & Engineering Value
This Grade 8 hex head screw delivers critical engineering value through its high-strength steel construction and UNC coarse thread design, specifically engineered to address common industrial fastening challenges. The 1/4"-20 thread size with Class 2A thread fit ensures precise engagement while the partial threading configuration provides optimal stress distribution across the 4-1/2" length. These features combine to prevent joint failure in heavy machinery, construction equipment, and automotive assemblies where vibration resistance and structural integrity are paramount. The external hex drive facilitates efficient installation with standard tools, reducing assembly time while maintaining the 150,000 PSI tensile strength required for critical connections in industrial environments.
Specification Summary & Compliance
Manufactured to ASME B18.2.1 and SAE J429 specifications with Class 2A thread fit tolerance for precise engagement. This 1/4"-20 UNC coarse thread hex head screw features partial threading and meets comprehensive compliance standards including RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and industrial durability requirements are fully satisfied.
