F436 Structural Flat Washer with Plain Finish

F436 Structural Flat Washers for Critical Steel Connections

When structural integrity and code compliance are non-negotiable, F436 structural flat washers deliver the heavy-duty performance required in demanding steel-to-steel assemblies. Designed specifically for high-load applications, these washers provide superior load distribution, prevent bolt head embedding, and maintain long-term joint stability in critical infrastructure projects.

Engineered for Strength and Reliability

Through-Hardened Construction

F436 structural washers are manufactured from medium carbon steel or alloy steel and are fully heat-treated to achieve precise mechanical properties. The thru-hardening process ensures uniform hardness throughout the washer, preventing crushing, cupping, or deformation under extreme clamping forces.

High Mechanical Performance

With hardness levels typically ranging from 38–45 HRC (Rockwell), these washers resist galling and surface embedding. Their increased thickness—compared to standard flat washers—allows them to withstand the high preload forces generated by structural bolts without compromising joint integrity.

Designed for Structural Bolt Compatibility

ASTM-Compliant Performance

F436 washers meet ASTM F436 specifications and are commonly paired with ASTM A325 and A490 structural bolts, as well as SAE J429 Grade 8 fasteners. This compatibility ensures proper performance in engineered structural assemblies that must meet stringent building codes and industry standards.

Precision Dimensions and Tolerances

Available in sizes typically ranging from 1/2" to 1-1/2" inner diameters and larger upon request, F436 washers are produced with tight tolerances to promote optimal bolt-hole alignment and secure clamping.

Finish Options for Any Environment

Corrosion Protection Choices

F436 structural washers are offered in multiple finishes to match environmental demands, including:

• Plain (uncoated) for controlled environments

• Hot-Dip Galvanized for superior outdoor corrosion resistance

• Zinc-Plated (Clear Zinc Cr3) for indoor or mildly corrosive conditions

Built for Infrastructure and Heavy Industry

These structural flat washers are widely used in bridges, commercial buildings, wind towers, heavy equipment, energy infrastructure, and large-scale steel fabrication. When safety, strength, and compliance matter most, F436 structural flat washers provide the dependable performance professionals trust.