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    14 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.
    Hot-Dipped Galvanized Steel—Combines the strength of steel with the rust resistance of stainless steel. These nuts are an economical alternative to 18-8 stainless steel in wet and outdoor environments, but they won't hold up to salt water and chemicals. The galvanized finish is thicker than other types of coatings, so the threads may be more likely to stick during installation. Use with other hot-dipped galvanized fasteners.
    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.
    Hot-Dipped Galvanized Steel
    1 1/4"-8
    		2"1 7/32"ASTM Grade 2H
    		ASTM A194
    		195025A43600000
     
    Steel
    1 1/4"-8
    		2"1 7/32"ASTM Grade 2H
    		ASTM A194
    		190521A2750000
     
    Blue PTFE-Coated Steel
    1 1/4"-8
    		2"1 7/32"ASTM Grade 2H
    		ASTM A194
    		190212A81100000
     

    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.
    High-Strength Steel
    Image of Product. Bottom orientation. Hex Nuts. Heavy-Profile Hex Nuts for High-Pressure Applications.
    Rated Grade 7 or Grade 8, these nuts 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-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1 1/4"-8
    		2"1 7/32"ASTM Grade 7
    		ASTM A194
    		194485A24000000
     
    Steel
    1 1/4"-8
    		2"1 7/32"ASTM Grade 7
    		ASTM A194
    		194485A1120000
     
    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.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    Highly Corrosion-Resistant 316 Stainless Steel
    1 1/4"-8
    		2"1 1/4"ASTM Grade 8M
    		ASTM A194
    		Material Certificate
    		197619A940000000
     

    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 1/4"-8
    		2 1/64"1 41/64"SAE Grade 8
    		185197135A404000000
     
    Steel
    1 1/4"-8
    		2 1/64"1 41/64"SAE Grade 8
    		185190630A21100000
     

    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
    Tools
    Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    Each
    Pronged
     
    18-8 Stainless Steel
    1 1/4"-8
    		1.875"1 1/4"
    		1.250"192335A1110000092335A311000000091709A310000000092450A192000000
     
    Extraction Tools
    Remove installed helical inserts.
    For Pronged Helical Inserts—Place the tip into pronged inserts and lightly strike the tool’s head. Then, turn the tool counterclockwise with pressure to extract the insert.
    For Thread Size
    Each
    For Pronged Helical Inserts
    1 1/8"-7, 1 1/8"-12, 1 1/4"-7, 1 1/4"-8, 1 1/4"-12, 1 3/8"-6, 1 3/8"-12, 1 1/2"-6, 1 1/2"-8, 1 1/2"-12, M27, M30, M36, M39
    		90254A3600000000
     

    Threaded Rod and Hex Nut Kits for Pipe Flanges

    Image of ProductInUse. Front orientation. Threaded Rods. Threaded Rod and Hex Nut Kits for Pipe Flanges.
    These kits include the rods and nuts you need to connect standard-size pipe flanges. Their heavy duty material and construction keep tanks, valves, and flanges tightly sealed under heavy pressure. With a 10% wider profile than standard hex nuts, these hex nuts spread force over a larger area and can handle extra torque during installation. The rods are fully threaded to distribute and absorb high levels of clamping force. To ensure your pipe flange connection is tight, add a pipe flange gasket to your installation. These rods and nuts meet a number of rigorous industry specifications for high-pressure performance, high-temperature performance, and dimensional requirements.
    Medium-Strength Steel
    Image of Product. Front orientation. Threaded Rods. Threaded Rod and Hex Nut Kits for Pipe Flanges, Steel.
    With a tensile strength of 125,000 psi, these rods are strong enough for most industrial applications, such as anchoring machinery and connecting pipe flanges. They are about twice as strong as low-strength steel rods.
    Corrosion-Resistant PTFE-Coated Steel—A PTFE coating protects the steel from corrosion and pitting when exposed to chemicals, such as those found in cleaners and sanitizers. The coating is also slippery to thread on smoothly.
    Threaded Rod
    Hex Nut
    Corrosion-Resistant
    PTFE-Coated Steel
    For Pipe
    Size
    Thread
    Size
    Lg.
    Tensile Strength,
    psi
    Specs.
    Met
    Thread
    Size
    Wd.
    Ht.
    Hex Nut
    Profile
    Specs.
    Met
    Hardness
    Fastener Strength
    Grade/Class
    No. of Threaded
    Rods Included
    No. of Nuts
    Included
    Color
    Each
    For Flange Class 1500
    4
    		1 1/4"-8
    		7 3/4"125,000ASTM A193
    		1 1/4"-8
    		2"1 7/32"HeavyASTM A194
    		Rockwell C35ASTM Grade B7
    		816Blue95064A2610000000
     
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