S-91268A177 1/4"-20 x 6" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

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 extended service life in demanding environments
• Optimized torque transmission through external hex drive design for secure installation and removal
• Enhanced thread engagement with UNC coarse threading and Class 2A fit for vibration resistance and quick assembly
• Strategic partial threading provides unthreaded shank section for improved shear strength and precise clamping
• Industry-standard compliance with ASME B18.2.1 and SAE J429 specifications for guaranteed interchangeability
• Environmental responsibility through RoHS 3 and REACH compliance, meeting modern regulatory requirements

Professional Applications & Engineering Value

These Grade 8 hex head screws deliver critical engineering solutions where high tensile strength and durability are paramount. The steel construction with Rockwell C33 hardness withstands extreme mechanical stresses in heavy machinery, construction equipment, and automotive assemblies. The 1/4"-20 UNC coarse thread configuration ensures rapid installation and superior resistance to vibration loosening, while the 6-inch length with partial threading provides optimal clamping force distribution. External hex drive design facilitates high-torque applications common in industrial maintenance and manufacturing, making these ASME B18.2.1 compliant fasteners ideal for critical structural connections requiring predictable performance and long-term reliability.

Specification Summary & Compliance

Manufactured to precise inch system dimensions with Class 2A thread fit tolerance for consistent performance. Thread specifications conform to UNC coarse thread standards with 1/4"-20 threading and 3/4" minimum thread length. Complies with ASME B18.2.1 mechanical specifications and SAE J429 Grade 8 requirements. Meets environmental standards including RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliance for hazardous substance restrictions.