Value Collection 581647PR Hex Socket Cap Screw 9/16-18 Unf

Product Description

The VALUE COLLECTION 581647PR is a partially threaded hex socket cap screw engineered for high-strength fastening applications. It features a 9/16-18 UNF thread size, a 4-inch length under head, and a 7/16-inch hex drive. Constructed from alloy steel with a black oxide coating, this fastener meets ASME/ANSI B18.3 and ASTM A574 standards, making it suitable for demanding mechanical and structural assemblies where tensile strength and dimensional precision are required. The black oxide finish provides a degree of corrosion resistance and reduces light reflection in finished assemblies.

This socket cap screw is used in industrial, mechanical, and trade service applications where a recessed hex drive is preferred over external-drive fasteners. Typical installations include machine frames, fixture plates, hydraulic component mounting, and equipment panels. The partial threading allows the unthreaded shank to act as a shoulder-like bearing surface in appropriate clearance-hole applications. It is handled by millwrights, machinists, HVAC equipment assemblers, and general mechanical contractors.

Key Features

• 9/16-18 UNF thread for fine-pitch engagement and vibration resistance
• 4-inch length under head suits deeper stack-up and thick-material fastening
• 7/16-inch hex socket drive for use with standard hex keys and socket drivers
• Alloy steel construction meets ASTM A574 high-strength requirements
• Black oxide coating provides mild corrosion resistance and low-reflectance finish
• Partial threading provides an unthreaded shank for precision clearance-hole alignment

Compatibility

Designed as a standard ASME/ANSI B18.3 hex socket cap screw compatible with any 9/16-18 UNF tapped hole requiring a 4-inch length under head and 7/16-inch internal hex drive.

Installation Notes

Installation requires a 7/16-inch hex key or socket bit driver rated for the torque demands of an ASTM A574 alloy steel fastener. Ensure mating threads are clean and free of debris before installation. Do not use an impact driver without a torque-limiting mechanism, as overtorquing can yield the fastener or damage tapped threads. Follow applicable machinery or equipment torque specifications for the assembly being serviced.