Value Collection 581790BR Hex Socket Cap Screw 7/8-14 Unf

Product Description

The VALUE COLLECTION 581790BR is a hex socket cap screw designed for high-strength fastening applications in industrial, mechanical, and structural assemblies. This fastener measures 4 inches in length under the head and features a 7/8-14 UNF thread form — a fine-thread specification that provides superior thread engagement and vibration resistance compared to coarse-thread equivalents. Drive is a 3/4-inch hex socket interface. The screw is partially threaded, which is standard for longer-body cap screws used in through-hole and clearance-fit assemblies. Manufactured from alloy steel with a black oxide coating, it offers improved corrosion resistance over bare steel in moderate-exposure environments. Machinists, millwrights, and maintenance technicians are the primary installers.

This cap screw is suited for use in precision machinery, hydraulic assemblies, tooling fixtures, and heavy equipment where a fine-thread fastener with high tensile strength is required. The 7/8-14 UNF size is commonly found in demanding mechanical joints, hydraulic cylinder ports, and equipment flanges. The black oxide finish blends into ferrous assemblies and provides light surface protection. It is sold as a single piece, making it appropriate for replacement or low-volume repair work.

Key Features

• 7/8-14 UNF fine thread for high clamping force and vibration resistance
• 4-inch length under head suits deep through-hole and thick flange applications
• 3/4-inch hex socket drive for high-torque installation with standard socket tooling
• Partially threaded shank provides a bearing surface in clearance-fit holes
• Alloy steel construction meets ASME/ANSI B18.3 and ASTM A574 standards
• Black oxide coating provides light corrosion resistance and reduces light reflection

Compatibility

Designed as a standard ASME/ANSI B18.3 and ASTM A574 compliant hex socket cap screw for use in any 7/8-14 UNF tapped hole requiring a 4-inch partially threaded fastener with a 3/4-inch hex socket drive.

Installation Notes

Installation should be performed by a qualified machinist, millwright, or maintenance technician using a 3/4-inch hex key or socket driver. Ensure the mating tapped hole is clean, free of debris, and threads are in good condition before installation. Apply thread lubricant or thread-locking compound as appropriate for the application and torque to the value specified by the equipment manufacturer or applicable engineering standard. Never install into a damaged or cross-threaded hole.