Value Collection 581578PS Hex Socket Cap Screw 1/2-20 Unf

Product Description

The VALUE COLLECTION 581578PS is a hex socket cap screw engineered for high-strength fastening applications in mechanical assemblies, fixtures, and industrial equipment. It features a 1/2-20 UNF thread size and measures 7/8 inches under the head with full threading along the shank. Driven by a 3/8-inch hex key, this fastener is manufactured from alloy steel with a black oxide coating that provides moderate corrosion resistance and reduces light glare in service environments. It meets ASME/ANSI B18.3 and ASTM A574 standards, making it a recognized fastener for precision and structural applications installed by machinists, millwrights, and mechanical contractors.

This socket cap screw is suited for use in tight-clearance installations where a standard hex head wrench cannot seat properly. The hex socket drive allows precise torque application with an Allen key or hex bit driver. Common applications include machinery frames, jigs and fixtures, hydraulic manifold assemblies, and general mechanical sub-assemblies in both residential and commercial equipment service. The black oxide finish is appropriate for indoor and low-moisture environments.

Key Features

• 1/2-20 UNF thread for fine-pitch fastening with greater thread engagement per inch
• Fully threaded shank for consistent clamping along the entire grip length
• 3/8-inch hex socket drive compatible with standard Allen keys and hex bit drivers
• Alloy steel construction meets ASTM A574 high-strength socket head cap screw requirements
• Black oxide coating provides mild corrosion resistance and a low-reflectance finish
• Conforms to ASME/ANSI B18.3 dimensional standards for consistent fit across tooling

Compatibility

Designed as a standard-dimension ASME/ANSI B18.3 hex socket cap screw suitable for any application requiring a 1/2-20 UNF fully threaded fastener with a 3/8-inch hex drive and 7/8-inch length under head.

Installation Notes

Installation is typically performed by machinists, millwrights, or mechanical service technicians using a 3/8-inch hex key or hex bit driver. De-energize and lock out all equipment before fastener removal or installation on powered machinery per OSHA lockout/tagout procedures. Do not exceed the rated torque range for 1/2-20 ASTM A574 alloy steel socket cap screws as specified by the equipment manufacturer. Inspect threads and seating surfaces for contamination or damage before installation to ensure proper clamp load.