Bowmalloy 36441 Hex Head Cap Screw 9/16-18 X 4 in Grade 9

Product Description

The BOWMALLOY 36441 is a Grade 9 alloy steel hex head cap screw in a 9/16-18 UNF thread size with a 4-inch length under the head. It carries a zinc-plated clear chromate finish for corrosion resistance in demanding service environments. The screw is partially threaded, which allows it to bear shear loads along the unthreaded shank. Licensed tradespeople and industrial maintenance crews specify this fastener for high-strength bolted connections where a standard Grade 5 or Grade 8 fastener would be undersized for the application.

This cap screw is suited for heavy equipment assembly, structural mounting, and mechanical drive applications where elevated tensile and proof-load requirements apply. Grade 9 alloy steel exceeds the minimum tensile strength of Grade 8, making it a common choice in agricultural equipment, off-highway machinery, and industrial fabrication. It installs with standard hex tooling and seats against flat or hardened washers depending on the joint design.

Key Features

• Grade 9 alloy steel construction for high tensile and proof-load performance
• 9/16-18 UNF (fine) thread profile for precise clamping force control
• 4-inch length under head accommodates thick stack-ups and structural members
• Partially threaded shank handles shear loads without thread engagement in the shear plane
• Zinc-plated clear chromate finish provides baseline corrosion protection
• Inch measurement system for compatibility with standard SAE tooling and hardware

Compatibility

Designed as an OEM-style replacement or upgrade fastener for applications requiring a 9/16-18 UNF partially threaded hex head cap screw meeting Grade 9 alloy steel specifications.

Installation Notes

Installation should be performed by a qualified mechanic or maintenance technician familiar with torque specifications for Grade 9 fasteners. Always confirm joint design requirements before substituting fastener grades. Apply a calibrated torque wrench to reach the specified clamp load for the joint; do not rely on impact tools alone for final torque. Inspect mating threads for damage or contamination before assembly.