S-91257A752 1/2"-20 x 3 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 capability with Grade 8 classification and 150,000 psi tensile strength for demanding industrial applications.
- Superior corrosion resistance provided by zinc yellow-chromate plating, extending service life in harsh environments.
- Precise thread engagement with Class 2A fit and UNF fine threading, ensuring reliable fastening and vibration resistance.
- Optimized torque transmission through the external hex drive and 3/4" head width, enabling secure installation with standard tools.
- Controlled thread engagement via partial threading, preventing over-tightening and distributing stress effectively.
- High durability backed by Rockwell C33 hardness, maintaining structural integrity under repeated stress.
- Regulatory compliance with ASME B18.2.1, RoHS 3, and REACH standards, ensuring safety and environmental responsibility.
Professional Applications & Engineering Value
Engineered for heavy-duty industrial applications, this Grade 8 hex head screw combines high-strength steel and zinc yellow-chromate plating to address critical challenges like joint failure and corrosion in machinery, construction, and automotive assemblies. The 1/2"-20 UNF fine thread and Class 2A fit provide superior vibration resistance and precise alignment, reducing maintenance needs in dynamic environments. With partial threading, it minimizes stress concentration, making it ideal for securing thick materials where full threading is unnecessary. This hex head screw delivers reliable performance in high-stress scenarios, from structural frameworks to equipment mounts, ensuring long-term operational safety and efficiency.
Specification Summary & Compliance
This fastener adheres to Class 2A thread fit and UNF thread standards with a 1/2"-20 size and 3 1/2" length. It meets ASME B18.2.1 manufacturing specifications and complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring precision and sustainability in industrial use.
