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    5 Products
    About Hex Nuts
    industrial info icon

    Choose a hex nut with the right profile, material, and strength for your application.

    Heavy-Profile Hex Nuts

    Image of Product. Front orientation. Hex Nuts. Heavy-Profile Hex Nuts.
    About 10% wider and taller than standard-profile hex nuts, these handle heavier loads by distributing them over a larger area.
    Extreme-Strength Steel
    These nuts are about 20% stronger than high-strength steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    PTFE-Coated Steel—A slippery PTFE coating prevents these nuts from becoming stuck during installation. They resist rust in wet and outdoor environments, however they're not recommended for prolonged exposure since the coating can wear off.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Steel
    2"-8
    		3 1/8"1 31/32"ASTM Grade 2H
    		ASTM A194
    		190521A046000000
     
    Blue PTFE-Coated Steel
    2"-8
    		3 1/8"1 31/32"ASTM Grade 2H
    		ASTM A194
    		190212A81700000
     

    Heavy-Profile Hex Nuts for High-Pressure Applications

    These nuts are hardened, so they maintain their strength under high pressure and temperature. Pair them with ASTM A193 screws to fasten critical components, such as valves and flanges, in pressure tanks, boilers, and heat exchangers. About 10% wider and taller than standard-profile hex nuts, these handle heavier loads by distributing them over a larger area.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Corrosion-Resistant Stainless Steel
    Image of Product. Bottom orientation. Hex Nuts. Heavy-Profile Hex Nuts for High-Pressure Applications.
    Highly Corrosion-Resistant 316 Stainless Steel—Superior to 18-8 stainless steel, these nuts won't degrade when exposed to harsh weather, salt water, and most chemicals.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    Highly Corrosion-Resistant 316 Stainless Steel
    2"-8
    		3 1/8"2 1/64"ASTM Grade 8M
    		ASTM A194
    		Material Certificate
    		197619A990000000
     

    Nylon-Insert Locknuts

    Image of Product. Front orientation. Locknuts. Nylon-Insert Locknuts.
    Versatile yet economical, these are the most commonly used locknuts. The nylon insert grips the screw to prevent loosening from moderate vibration without damaging threads. However, the insert may become brittle if exposed to high temperatures. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    High-Strength Steel
    Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Black-Oxide Steel—Typically chosen for their appearance, these nuts have a dark, matte coating to create a finished look. They offer minimal corrosion resistance, so they're best for dry environments.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Black-Oxide Steel
    2"-8
    		3 9/64"2 13/32"SAE Grade 8
    		220197135A454000000
     
    Steel
    2"-8
    		3 9/64"2 13/32"SAE Grade 8
    		220190630A21900000
     
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