S-91251A007 7/16"-20 x 3 1/2" ASTM A574 Alloy Steel Socket Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 170,000 psi ensures reliable performance in high-stress industrial applications, reducing failure risks.
• Black-oxide coating on alloy steel provides enhanced corrosion resistance, extending service life in harsh environments.
• Class 3A thread fit delivers superior precision and vibration resistance for secure, long-lasting assemblies.
• Partially threaded design allows for optimal clamping force control and easier alignment in machinery setups.
• Hex socket drive enables high-torque installation with standard tools, minimizing stripping and improving efficiency.
• Fine thread spacing (UNRF) offers improved load distribution and finer adjustment capabilities in precision equipment.
• Compliance with ASTM A574, RoHS 3, and REACH ensures material consistency and environmental safety for global supply chains.

Professional Applications & Engineering Value

These Black-Oxide Alloy Steel Socket Head Cap Screws are engineered to address critical challenges in demanding sectors like automotive, aerospace, and heavy machinery. The UNRF fine thread configuration enhances fatigue resistance and prevents loosening under dynamic loads, while the Rockwell C37 hardness balances durability with machinability. The partially threaded rod type concentrates stress away from the head, reducing fracture risks in assembled components. Ideal for precision industrial applications, the hex drive facilitates secure installations in confined spaces, and the black-oxide surface treatment provides a protective layer against oxidation without compromising dimensional accuracy. This combination ensures reliable performance in corrosive or high-vibration environments, supporting long-term operational integrity.

Specification Summary & Compliance

This product adheres to Class 3A thread fit for precise tolerance and UNRF fine thread standards with a size of 7/16"-20. It meets ASTM A574 specifications for alloy steel socket head cap screws, ensuring material and manufacturing consistency. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, it supports environmental and safety requirements in industrial procurement.