Plain washers for high-strength structural bolting, hardened and tempered
This International Standard specifies those hardened and tempered circular washers intended for assembly with large series hexagon high-strength structural bolts and nuts of diameters from M12 to M36 inclusive.

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ISO general purpose metric screw threads — Tolerances — Part 4: Limits of sizes for hot -dip galvanized external screw threads to mate with internal screw threads tapped with tolerance position H or G after galvanizing
Hexagon washer head tapping screws
“TWIST OFF” TYPE TENSION CONTROL STRUCTURAL BOLT/NUT/WASHER ASSEMBLIES, STEEL, HEAT TREATED, 150 KSI MINUMUM TENSILE STRENGTH
TEST PROCEDURE FOR THE PERFORMANCE OF NONMETALLIC RESISTANT ELEMENT PREVAILING-TORQUE NUTS-INCH SERIES
SURFACE DISCONTINUITIES OF BOLTS, SCREWS, AND STUDS
ALUMINUM TRANSMISSION TOWER BOLTS AND NUTS