Value Collection 5188CH8O Hex Cap Screw 1/2-20 X 5-1/2 in Grade 8

Product Description

The VALUE COLLECTION 5188CH8O is a partially threaded hex head cap screw engineered for high-strength fastening applications. It is manufactured from Grade 8 steel and finished with a zinc yellow dichromate coating that provides corrosion resistance in demanding environments. The screw measures 1/2-20 UNF thread size with a 5-1/2 inch length under head, making it well suited for heavy-duty mechanical assemblies. With a tensile strength of 150,000 psi, it meets the requirements of ASME B18.2.1 and SAE J429. Installed with a 3/4 inch hex key or wrench, this fastener is a dependable choice for industrial and structural fastening work.

This fastener is appropriate for use in industrial machinery, structural steel assemblies, agricultural equipment, automotive applications, and other heavy-duty mechanical systems where high-clamp-load and torque resistance are required. The partial threading allows the unthreaded shank to bear shear loads, which is an advantage in joint designs that demand precise alignment or load distribution across the grip length. Maintenance technicians, millwrights, and mechanical contractors routinely spec Grade 8 fasteners like this one for critical bolted connections.

Key Features

• Grade 8 steel construction with 150,000 psi tensile strength for high-load fastening
• Zinc yellow dichromate finish for corrosion protection in industrial environments
• Partially threaded shank allows the grip length to carry shear loads
• 1/2-20 UNF thread form for fine-thread engagement and superior vibration resistance
• Meets ASME B18.2.1 and SAE J429 dimensional and mechanical standards
• 3/4 inch hex drive compatible with standard wrenches and sockets

Compatibility

Designed as a standard inch-series hex head cap screw for use in any application requiring a 1/2-20 UNF partially threaded fastener with a 5-1/2 inch length under head and Grade 8 mechanical properties.

Installation Notes

Installation is performed with a 3/4 inch open-end, box, or socket wrench. De-energize, depressurize, or otherwise render safe any equipment before removing or replacing structural fasteners. Apply fastener torque values per the joint designer's specification or applicable engineering standards — do not estimate torque without reference data for the specific joint. Inspect threads and mating surfaces for damage before assembly; replace any fastener that shows signs of thread galling, corrosion, or mechanical deformation.