Value Collection 581549PR Hex Socket Cap Screw 1/2-13 Unc

Product Description

The VALUE COLLECTION 581549PR is a partially threaded hex socket cap screw designed for high-strength fastening in mechanical and structural assemblies. Sized at 1/2-13 UNC with a 3-3/4 inch length under head, it accepts a 3/8 inch hex drive for secure torque application. Constructed from alloy steel with a black oxide finish, this fastener resists corrosion and meets the dimensional and mechanical requirements of ASME/ANSI B18.3 and ASTM A574. It is suited for industrial maintenance, machine building, and fabrication work where a flush, recessed-drive fastener is required.

This socket cap screw is used in applications where a standard hex bolt head would interfere with surrounding components or clearance is limited. The partially threaded shank provides a clamp load bearing surface and is appropriate for through-bolting, fixture assembly, and equipment repair in manufacturing, heavy equipment, and general mechanical trade work. Its black oxide coating provides mild corrosion resistance for indoor and protected environments.

Key Features

• 1/2-13 UNC thread size for broad compatibility with standard inch-thread hardware
• 3-3/4 inch length under head with partial threading for shank bearing applications
• 3/8 inch hex socket drive for use with standard Allen keys and hex bit sockets
• Alloy steel construction meets ASTM A574 mechanical requirements
• Black oxide finish provides corrosion resistance in protected environments
• Conforms to ASME/ANSI B18.3 dimensional standards

Compatibility

Designed as a standard ASME/ANSI B18.3 hex socket cap screw for use in any application requiring 1/2-13 UNC partially threaded fasteners with a 3/8 inch hex drive.

Installation Notes

Installation is performed with a 3/8 inch hex key or socket bit driver; verify proper seating before applying final torque. Ensure the mating tapped hole or nut meets 1/2-13 UNC thread specifications to avoid cross-threading. De-energize and lock out all equipment before fastener service on machinery per applicable safety standards. Do not use this fastener in applications requiring stainless or plated finishes where black oxide is not rated for the service environment.