Bowmalloy 36412 Hex Head Cap Screw 1/2-20 X 3 in Grade 9

Product Description

The BOWMALLOY 36412 is a Grade 9 alloy steel hex head cap screw designed for high-strength fastening applications in mechanical, structural, and industrial assemblies. It features a 1/2-20 UNF thread size with a 3-inch length under head and a partial thread configuration, making it well-suited for clamping joints where a shank grip length is required. The zinc-plated clear chromate finish provides a baseline level of corrosion resistance for general-purpose use. This fastener is installed by millwrights, maintenance technicians, and mechanical contractors working on equipment, machinery mounts, and structural connections.

The 36412 is suited for demanding fastening applications that require higher proof load and tensile strength than Grade 5 or Grade 8 hardware. The 1/2-20 fine-thread profile provides better thread engagement and resistance to loosening under vibration compared to coarse-thread equivalents. Partial threading allows the unthreaded shank to bear shear loads at the joint interface, a common requirement in precision mechanical assemblies and equipment mounting situations.

Key Features

• Grade 9 alloy steel construction for high proof load and tensile strength demands
• 1/2-20 UNF fine thread for improved vibration resistance and thread engagement
• 3-inch length under head with partial threading to support shear load at the joint
• Zinc-plated clear chromate finish for baseline corrosion protection
• Hex head drive for standard hex socket or open-end wrench installation

Compatibility

Designed as a standard UNF hex head cap screw for use in any application requiring a 1/2-20 x 3-inch Grade 9 alloy steel fastener with a zinc-plated clear chromate finish.

Installation Notes

Install with a calibrated torque wrench to the torque specification appropriate for Grade 9 1/2-20 fasteners per the applicable engineering or equipment service documentation. Ensure mating threads are clean and free of debris before installation. Do not use an impact driver at full torque without a torque-limiting setting, as over-torquing can damage the fastener or mating material. Follow applicable ASME or equipment OEM standards for fastener installation procedures.