S-91251A891 10-24 x 4 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 applications, reducing the risk of fastener failure.
• Superior corrosion resistance from the black-oxide finish extends service life in demanding industrial environments.
• Precise Class 3A thread fit provides tighter tolerances for secure, vibration-resistant assemblies with minimal backlash.
• Partially threaded design with a minimum 7/8" thread length allows for controlled clamping force and easier alignment in assemblies.
• High hardness (Rockwell C37) enhances wear resistance, maintaining thread integrity through repeated use.
• Coarse UNC 10-24 threads enable quick installation and are less prone to clogging in dirty or debris-filled conditions.
• Standard hex socket drive (5/32") offers efficient torque transfer and access in confined spaces.

Professional Applications & Engineering Value

Engineered for heavy-duty industrial applications, these black-oxide alloy steel socket head cap screws address critical challenges in machinery, automotive, and construction sectors. The UNC coarse thread design ensures rapid assembly and resistance to cross-threading, while the partially threaded shank concentrates stress away from the head, reducing the risk of fatigue failure. With a 170,000 psi tensile strength and Rockwell C37 hardness, they withstand extreme loads and repetitive motion, making them ideal for high-vibration environments. The black-oxide surface treatment provides a durable, mildly corrosion-resistant layer, prolonging fastener life without sacrificing dimensional accuracy. These screws are trusted in applications requiring reliable, high-strength fastening with consistent performance under demanding conditions.

Specification Summary & Compliance

This socket head cap screw adheres to Class 3A thread fit for precise, tight-tolerance assemblies and follows UNC 10-24 coarse thread standards. Manufactured in compliance with ASTM A574 specifications, it meets rigorous quality and performance benchmarks. The product is fully RoHS 3 (2015/863/EU) compliant and REACH (EC 1907/2006) compliant, ensuring environmental safety and regulatory adherence for global supply chains.