STAINLESS STEEL USA 800 SERIES FLAT WASHERS

USA 800 Series Flat Washers — The 800 Series is a heavier-gauge option within the broader USA flat washer catalogue - running noticeably thicker than a standard USS-pattern flat washer for the same imperial bolt size, in much the same way DIN 9021 or a large-series ISO washer offers more material than a general-purpose metric flat washer. That extra thickness and bearing area matters specifically where a joint is working closer to its rated preload than typical general assembly, or where the clamped material is soft enough that a standard-gauge imperial washer would risk embedding or crushing under load; for ordinary general-purpose fixing work, a standard USA flat washer usually remains the more economical and entirely adequate choice. Whether the 800 Series is suitable for high-tensile imperial bolts depends on the washer's hardness and thickness relative to the bolt grade and preload it is carrying - where Grade 8 equivalent or higher-tensile bolts are involved, the washer's hardness should be checked as adequate for the resulting bearing stress before specifying it, rather than assuming a heavier gauge automatically means it can handle any bolt grade. It is specified alongside its own position within the wider imperial flat washer catalogue, so the exact outside diameter and thickness for a given bolt size should be checked against the catalogue dimensions before quoting, rather than assumed to scale directly from the standard series. Material selection follows the usual pattern: carbon steel with a protective plating for general-purpose imperial fixing work, and stainless steel grades - A2 (304-equivalent) as the default, A4 (316-equivalent) for marine, coastal, or chemically aggressive environments - wherever the equipment operates somewhere A2's corrosion resistance would eventually be tested by chloride exposure. To choose correctly, confirm the imperial bolt diameter, verify the 800 Series designation matches the outside diameter and thickness the application actually needs, and select a material and finish suited to the service environment.

FAQs
How does the 800 Series differ from a standard USA flat washer?
Standard USA flat washers cover a general-purpose series, while the 800 Series represents a specific size and weight designation within the broader imperial flat washer family, distinguished by its own outside diameter and thickness for a given bolt size.

Is the 800 Series suitable for use with high-tensile imperial bolts?
Suitability depends on the washer's hardness and thickness relative to the bolt grade and preload; where high-tensile bolts are used, washer hardness should be confirmed as adequate for the resulting bearing stress before specifying.

What materials is the 800 Series available in?
Commonly carbon steel with a protective plating and, where corrosion resistance is needed, stainless steel grades suited to the application environment.