Value Collection 581588PR Hex Socket Cap Screw 1/2-20 Unf

Product Description

The VALUE COLLECTION 581588PR is a partially threaded hex socket cap screw engineered for high-strength fastening in precision mechanical assemblies. It features a 1/2-20 UNF thread size, a 3-1/2 inch length under head, and a 3/8 inch hex drive socket. Constructed from alloy steel and finished with a black oxide coating, this cap screw provides solid tensile strength and moderate corrosion resistance in controlled environments. It meets ASME/ANSI B18.3 and ASTM A574 standards, making it a recognized choice for structural and mechanical fastening applications where torque and clamping load matter.

This cap screw is suited for use in manufacturing, maintenance, and mechanical assembly applications across industrial and commercial settings. The 1/2-20 UNF fine thread pitch is commonly specified where thread engagement strength and vibration resistance are priorities. The partial threading allows the unthreaded shank to bear shear loads, a common requirement in flanged joints, tooling fixtures, and machinery frames. Installation is performed by qualified millwrights, machinists, or maintenance technicians using a standard 3/8 inch hex key or Allen driver.

Key Features

• 1/2-20 UNF fine thread for strong thread engagement and vibration resistance
• 3-1/2 inch length under head with partial threading for shear load capability
• 3/8 inch hex socket drive for torque application with standard Allen tooling
• Alloy steel construction provides high tensile and yield strength
• Black oxide finish offers mild corrosion resistance and reduced light reflection
• Meets ASME/ANSI B18.3 and ASTM A574 standards

Compatibility

Designed as an OEM-style replacement or standard-specification fastener for mechanical assemblies requiring a 1/2-20 UNF partially threaded hex socket cap screw conforming to ASME/ANSI B18.3 and ASTM A574.

Installation Notes

Installation should be performed by a qualified technician using a properly sized 3/8 inch hex key or torque wrench attachment. Always de-energize and lock out any equipment before servicing fasteners in live assemblies. Do not exceed the fastener's rated torque specification for the thread and material class. Use thread lubricant or anti-seize only where specified by the equipment manufacturer.