Value Collection 581678BR Hex Socket Cap Screw 5/8-18 Unf

Product Description

The VALUE COLLECTION 581678BR is a partially threaded hex socket cap screw designed for high-strength fastening applications across industrial, mechanical, and structural assembly work. It features a 5/8-18 UNF thread size, a 3.5-inch length under head, and a 0.5-inch hex drive. Manufactured from alloy steel with a black oxide coating, this fastener delivers solid corrosion resistance and retains the mechanical strength required for demanding torque environments. It meets ASME/ANSI B18.3 and ASTM A574 standards, making it a reliable choice for precision-fit assemblies where thread engagement and material integrity are critical.

This cap screw is suited for mechanical equipment assembly, fixture fabrication, and structural fastening tasks where a fine-thread UNF specification is required. The 5/8-18 UNF thread pitch provides tighter thread engagement compared to coarse-thread equivalents, making it a preferred choice when vibration resistance or precise clamping force matters. Typical installations include machine frames, pump housings, motor mounts, and other heavy mechanical assemblies. This fastener is sold individually but requires a minimum order of 10 units.

Key Features

• 5/8-18 UNF fine thread for tight engagement and vibration resistance
• Partially threaded shank for controlled clamping and shear strength
• Alloy steel construction meets ASTM A574 high-strength requirements
• Black oxide finish for moderate corrosion resistance in dry or lightly oiled environments
• 0.5-inch hex socket drive compatible with standard hex keys and socket drivers
• Conforms to ASME/ANSI B18.3 dimensional standards

Compatibility

Designed as an OEM-style replacement or standard-fit fastener for any application requiring a 5/8-18 UNF partially threaded hex socket cap screw meeting ASME/ANSI B18.3 and ASTM A574 specifications.

Installation Notes

Installation is typically performed by machinists, millwrights, or maintenance technicians using a calibrated torque wrench with a 0.5-inch hex bit. Ensure mating threads are clean and free of debris before installation. Apply thread lubricant or anti-seize compound only when consistent with the application engineering requirements. Do not exceed the rated torque range for the alloy steel grade to avoid fastener failure or thread stripping.