S-91286A141 1/4"-28 x 1 1/2" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional strength and durability with Grade 8 classification, providing 150,000 psi tensile strength and Rockwell C33 hardness for heavy-duty applications
• Superior corrosion resistance due to the zinc-flake coating, ensuring long-lasting performance in harsh industrial environments
• Precise thread engagement with 1/4"-28 UNF fine threads and Class 2A fit, reducing the risk of cross-threading and ensuring reliable fastening
• Optimized load distribution from the partially threaded design, minimizing stress concentration and enhancing joint integrity
• Easy installation and removal with the external hex drive and standard 7/16" head width, allowing for quick assembly with common tools
• Compliance with industry standards including ASME B18.2.1 and SAE J429, ensuring consistent quality and interchangeability
• Environmental and safety adherence with RoHS 3 and REACH compliance, making it suitable for regulated industries

Professional Applications & Engineering Value

This Grade 8 hex head screw is engineered to address critical challenges in demanding industrial settings, such as machinery assembly, automotive systems, and structural frameworks. Its high-strength steel construction and zinc-flake coating provide robust protection against corrosion and wear, extending service life in environments exposed to moisture, chemicals, or high stress. The 1/4"-28 UNF fine threads with Class 2A fit ensure tight, vibration-resistant connections, reducing maintenance needs and preventing loosening under dynamic loads. Partially threaded design allows for precise clamping force control, making it ideal for applications where thread engagement length must be optimized to avoid weak points. By meeting ASME B18.2.1 and SAE J429 specifications, it guarantees reliability in heavy-duty fastening scenarios, from construction equipment to manufacturing lines, enhancing overall operational efficiency and safety.

Specification Summary & Compliance

This fastener adheres to precise dimensional tolerances, including Class 2A thread fit for consistent assembly and UNF fine threading (1/4"-28) to meet inch system requirements. It conforms to ASME B18.2.1 and SAE J429 standards for material and mechanical properties, ensuring high-quality manufacturing. Additionally, it is RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, supporting environmental safety and regulatory adherence in industrial supply chains.