Value Collection D39447 Hex Cap Screw 5/8-18 X 1-1/2 Grade 8

Product Description

The VALUE COLLECTION D39447 is a fully threaded hex head cap screw designed for high-strength fastening applications in mechanical, structural, and industrial assembly work. It is manufactured from Grade 8 steel, the highest commonly specified inch-series fastener grade, delivering a proof load strength suitable for demanding bolted joints. The screw measures 5/8-18 UNF in thread size with a 1-1/2 inch length under head. A zinc yellow dichromate finish provides corrosion resistance while serving as a visual identifier for Grade 8 hardware. This fastener conforms to ASME B18.2.1 dimensional standards and is installed by mechanics, millwrights, and general tradespeople across a wide range of applications.

This hex head cap screw is suited for use in high-load bolted assemblies where fine-thread engagement and Grade 8 strength are required. Fine-thread UNF fasteners offer greater resistance to loosening under vibration compared to coarse-thread equivalents, making this screw appropriate for equipment, machinery, and vehicle or trailer hardware where joint integrity under dynamic loads is a priority. It is sold individually with a minimum order quantity of 10 pieces.

Key Features

• Grade 8 steel construction for high proof load and tensile strength in demanding bolted joints
• 5/8-18 UNF fully threaded profile provides maximum thread engagement over the full 1-1/2 inch length under head
• Zinc yellow dichromate finish delivers corrosion resistance and serves as the standard Grade 8 visual identifier
• Conforms to ASME B18.2.1 dimensional standards for consistent fitment with Grade 8 nuts and washers
• Fine-thread UNF series resists loosening under vibration better than coarse-thread equivalents

Compatibility

Designed for use with 5/8-18 UNF Grade 8 hex nuts and hardened flat washers in standard inch-series bolted assemblies per ASME B18.2.1.

Installation Notes

This fastener is installed by mechanics, millwrights, and tradespeople using a standard hex wrench or socket. Always use a hardened flat washer under the head when bearing surface hardness requires it, and pair with a Grade 8 or equivalent nut. Ensure mating threads are clean and free of debris before assembly. Torque to the value specified by the equipment manufacturer or relevant structural standard for 5/8-18 Grade 8 fasteners.