Bowmalloy BOWMP36112 Hex Head Cap Screw 1/2-13x3 Grade 9

Product Description

The BOWMALLOY BOWMP36112 is a 1/2-13 x 3-inch hex head cap screw manufactured from Grade 9 steel with a Bowma-Guard protective finish. This is a partially threaded fastener, meaning the shank transitions from an unthreaded grip area to the threaded section, which provides shear strength and accurate clamping in structural and mechanical assemblies. It is installed by millwrights, maintenance mechanics, and field service technicians working on heavy equipment, industrial machinery, and structural steel applications. The Bowma-Guard finish provides corrosion resistance beyond standard zinc plating, making this screw appropriate for demanding environments.

This cap screw is suited for industrial and commercial applications where high-strength fastening is required. Typical use cases include securing flanges, brackets, bearing housings, and structural members in manufacturing, agriculture, mining, and transportation equipment. The 1/2-13 thread designation follows Unified National Coarse (UNC) standard, compatible with standard 1/2-13 hex nuts and tapped holes of the same specification. Partial threading is standard for bolts where a smooth shank is needed through clearance holes before threading into a tapped bore or nut.

Key Features

• Grade 9 steel construction for high tensile and proof load strength beyond Grade 8
• Bowma-Guard finish provides enhanced corrosion resistance over standard zinc plate
• Partially threaded shank supports shear loading and accurate joint clamping
• 1/2-13 UNC thread conforms to Unified National Coarse inch-series standard
• 3-inch length under head suits medium to deep grip-length applications
• Hex head drive accepts standard hex wrenches and impact sockets

Compatibility

Designed for use with standard 1/2-13 UNC hex nuts, flat washers, and lock washers in inch-series fastener applications. Fits any clearance hole and tapped bore sized for 1/2-13 UNC thread engagement.

Installation Notes

Installation is performed by qualified mechanics or millwrights using a calibrated torque wrench or impact driver with the appropriate 3/4-inch hex socket. Always verify thread engagement depth and ensure the mating nut or tapped hole is clean and undamaged before assembly. Follow equipment manufacturer torque specifications and applicable ASME or industry fastener standards for the joint being assembled. Do not mix Grade 9 fasteners with lower-grade nuts or hardware, as mismatched strength grades can compromise joint integrity.