Gibraltar Z9281 Structural Flat Washer 1-1/4 in Alloy Steel

Product Description

The GIBRALTAR Z9281 is a structural flat washer designed for heavy-duty fastening applications requiring load distribution and corrosion resistance. Built from alloy steel with a zinc yellow dichromate finish, this washer meets the demands of structural bolted connections in construction, fabrication, and mechanical assembly work. It is sized for a 1-1/4 inch screw, with a 1-3/8 inch inside diameter, 2-1/2 inch outside diameter, and a 1/4 inch thickness. The Rockwell C43-C49 hardness rating makes it suitable for high-load structural joints where a standard washer would not hold up. Installers across structural steel, heavy equipment, and industrial maintenance trades will find this washer fits standard specification work.

This washer is used in structural bolting applications across residential, commercial, and industrial projects. Typical use cases include steel beam connections, anchor bolt assemblies, heavy machinery mounting, and infrastructure fastening where bearing surface area and material hardness are critical. The zinc yellow dichromate finish provides a corrosion-inhibiting layer suited for indoor and sheltered outdoor environments. It is sold individually and is appropriate wherever a 1-1/4 inch structural flat washer is specified per project or fabrication requirements.

Key Features

• Alloy steel construction with Rockwell C43-C49 hardness for structural-grade load bearing
• Zinc yellow dichromate finish for corrosion resistance in demanding environments
• 1-3/8 inch inside diameter fits 1-1/4 inch screw or bolt assemblies
• 2-1/2 inch outside diameter provides broad bearing surface for load distribution
• 1/4 inch thickness supports high-clamp-load structural connections
• Inch measurement system; UNSPSC Code 31161807

Compatibility

Designed as an OEM-style structural flat washer for use with 1-1/4 inch fasteners in structural bolting assemblies per applicable project specifications.

Installation Notes

Installation is typically performed by structural iron workers, millwrights, or general contractors following applicable building codes and bolt specification standards. Always ensure the mating fastener and nut are rated for the same structural class before assembly. Torque fasteners using calibrated tooling in accordance with the project engineer or specification sheet. Do not substitute this washer in applications requiring a different hardness class or dimensional standard without engineering review.