S-91879A030 5/16"-18 ASME B18.2.2, ASTM A194 Hex Nuts

Key Features & Benefits at a Glance

• Superior corrosion resistance with zinc-plated steel construction, extending service life in harsh industrial environments
• Exceptional load distribution due to the extra-wide thin profile, reducing risk of material deformation under high stress
• Reliable high-strength performance with ASTM Grade 2H rating, ensuring secure fastening in heavy-duty applications
• Easy installation and compatibility with UNC coarse threads and Class 2B fit, providing smooth assembly with standard 5/16"-18 bolts
• Guaranteed dimensional accuracy per ASME B18.2.2 specifications, ensuring consistent fit and interchangeability
• Compliance with global environmental standards including RoHS 3 and REACH, making them safe for regulated industries
• Optimized for space-constrained designs with a 13/64" height, ideal for thin-section assemblies without sacrificing strength

Professional Applications & Engineering Value

This 5/16"-18 UNC hex nut is engineered to address common industrial challenges such as vibration loosening and corrosion-induced failure. The zinc-plated steel material provides a durable barrier against moisture and chemicals, significantly reducing maintenance needs in outdoor or corrosive settings like construction, automotive, and machinery. Its extra-wide thin profile distributes clamping force more evenly, preventing joint fatigue in high-vibration environments. The coarse thread design ensures quick assembly and resistance to cross-threading, while the Class 2B thread fit offers a balance of ease in installation and reliable retention. Ideal for structural frameworks, equipment manufacturing, and assembly lines, this nut delivers consistent performance where ASTM Grade 2H strength and compliance with ASME B18.2.2 are critical for safety and durability.

Specification Summary & Compliance

This hex nut features precise Class 2B thread fit with UNC coarse threads (5/16"-18) and right-hand direction, manufactured to ASME B18.2.2 dimensional standards. It complies with material specifications under ASTM A194 and strength requirements for ASTM Grade 2H. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring adherence to environmental and safety guidelines. Dimensions include a width of 9/16" and height of 13/64", providing consistent performance in inch-system applications.