Value Collection R57001291 Hex Head Cap Screw 18-8 Ss

Product Description

The VALUE COLLECTION R57001291 is a partially threaded hex head cap screw designed for heavy-duty fastening applications. Machined to an inch-series 1-1/8-7 UNC thread and measuring 5-1/2 inches under the head, this screw is manufactured from 18-8 stainless steel with no additional finish coating. The 18-8 alloy provides reliable corrosion resistance in wet, outdoor, and mildly chemical environments. At 2.5 pounds, this is a large-diameter fastener intended for structural or mechanical assemblies where a standard coarse-thread hex cap screw is specified. Machinists, millwrights, pipefitters, and general contractors typically install this type of fastener.

This hex head cap screw is suited for use in industrial, commercial, and heavy mechanical installations. Partial threading allows for a smooth shank section, making it appropriate for joints where the unthreaded shank spans a clamped material layer and only the threaded end engages the mating nut or tapped hole. Typical applications include structural steel connections, pump and compressor mounting, flange bolting, and equipment frame assembly where UNC thread engagement and stainless corrosion resistance are both required.

Key Features

• 1-1/8-7 UNC coarse thread for broad compatibility with standard inch-series hardware
• 5-1/2 inch length measured under the head
• Partially threaded shank for precise clamping and load distribution across joined materials
• 18-8 stainless steel construction for corrosion resistance without additional coating
• Uncoated finish maintains true dimensional tolerances on thread engagement
• Sold individually, no minimum quantity required beyond a single piece

Compatibility

Designed as a standard inch-series UNC hex head cap screw for use with any 1-1/8-7 threaded nut, tapped hole, or mating fastener hardware in that size and thread standard.

Installation Notes

Installation is typically performed by a millwright, pipefitter, or maintenance mechanic using a hex wrench, socket, or impact driver sized to the hex head. Always torque to the value specified in the relevant engineering or code document for the assembly. De-energize, depressurize, or otherwise isolate any equipment before fastener replacement. Avoid mixing stainless fasteners with dissimilar metals in applications where galvanic corrosion is a concern.