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    9 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

    About 10% wider and taller than standard-profile hex nuts, these handle heavier loads by distributing them over a larger area.
    Extreme-Strength Steel
    Image of Product. Front orientation. Hex Nuts. Heavy-Profile Hex Nuts.
    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
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    Steel
    1 3/4"-8
    		2 3/4"1 23/32"ASTM Grade 2H
    		ASTM A194
    		Material Certificate
    		190521A044000000
     
    Blue PTFE-Coated Steel
    1 3/4"-8
    		2 3/4"1 23/32"ASTM Grade 2H
    		ASTM A194
    		—190212A81500000
     

    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
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    Qty.
    Pkg.
    Highly Corrosion-Resistant 316 Stainless Steel
    1 3/4"-8
    		2 3/4"1 3/4"ASTM Grade 8M
    		ASTM A194
    		Material Certificate
    		197619A980000000
     

    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.
    Zinc-Yellow-Chromate-Plated Steel—With a more durable finish than clear zinc plating, these nuts are suitable for most wet and outdoor environments. However, they won't hold up to the harsh chemicals that stainless steel can.
    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.
    Zinc-Yellow-Chromate-Plated Steel
    1 3/4"-8
    		2 49/64"2 5/16"SAE Grade 8
    		185197135A411000000
     
    Steel
    1 3/4"-8
    		2 49/64"2 5/16"SAE Grade 8
    		185190630A21700000
     

    Helical Threaded Inserts

    Image of Product. Pronged. Bottom orientation. Threaded Inserts. Helical Threaded Inserts, Pronged.

    Pronged

    Restore, reinforce, or create threads in metal. The tough coils on these inserts expand once installed to anchor in a tapped hole. Also known as Heli-Coil inserts, they're often used in engine heads and machinery housings where strong connections are critical. Unlike threadlocking inserts, you can remove and reuse them without them losing their strength.
    Installation requires a drill bit, a helical insert tap, and an installation tool.
    Pronged—The prong attaches to an installation tool for precise control as you drive inserts in. Remove the prong with a punch or break-off tool before inserting a screw.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Through-Hole
    Taps
    Closed-End
    Hole Taps
    Installation
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    Pronged
     
    18-8 Stainless Steel
    1 3/4"-8
    		2.625"1 3/4"
    		1.750"192335A11900000092335A319000000091709A330000000092450A194000000
     
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