Hex Nuts

Hex nuts are six-sided internally threaded fasteners that are used to secure connections. 

Frequently Asked Questions About Hex Nuts

What are hex nuts used for? 

Hex nuts are used in virtually every industry, including construction/engineering, electrical, and OEM/MRO. 

What grades are hex nuts available in?

Hex nuts are available in the following grades:
•    Grade 2: most versatile and commonly used nut design, paired with any non-heat-treated low carbon bolt or screw
•    Grade 5: paired with bolts with a minimum tensile strength equal to or less than the specified proof stress of the nut (typically Grade 5 hex cap screws) 
•    Grade 8: paired with bolts with a minimum tensile strength equal to or less than 150,000 psi (typically Grade 8 hex cap screws) 
•    Stainless Steel 18-8 & 316: corrosion resistant, designed for use with stainless steel bolts and screws with a specified minimum tensile strength equal to or less than the specified proof stress of the mating nut

What is the difference between a hex nut and a heavy hex nut? 

Hex nuts are of standard thickness and strength, whereas heavy hex nuts are thicker and stronger (as well as wider). 

What sizes do hex nuts come in?

AFT offers hex nuts in both metric and imperial sizes. Diameter-thread sizes range from #2-56 to 3”-12 or M1.6-0.35 to M90-4.00. 

What materials and finishes are hex nuts available in? 

Hex nuts are available in many materials and finishes. They are made of steel, stainless steel, brass, aluminum, silicon bronze, nylon, and ni-cu alloy steel. Finishes include black, black oxide, cadmium yellow and wax, hot dipped galvanized, plain, zinc, zinc bake Cr+3, zinc Cr+3, zinc yellow, or zinc yellow Cr+6. Stainless steel and zinc offer additional corrosion resistance.