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    34 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 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.
    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
    1/4"-20
    1/2"1/4"ASTM Grade 8M
    ASTM A194
    Material Certificate
    5097619A890000000
    5/16"-18
    9/16"19/64"ASTM Grade 8M
    ASTM A194
    Material Certificate
    1097619A1100000
    3/8"-16
    11/16"23/64"ASTM Grade 8M
    ASTM A194
    597619A2200000
    7/16"-14
    3/4"27/64"ASTM Grade 8M
    ASTM A194
    Material Certificate
    597619A3300000
    1/2"-13
    7/8"31/64"ASTM Grade 8M
    ASTM A194
    Material Certificate
    597619A4400000
    5/8"-11
    1 1/16"39/64"ASTM Grade 8M
    ASTM A194
    Material Certificate
    197619A5500000
    3/4"-10
    1 1/4"47/64"ASTM Grade 8M
    ASTM A194
    Material Certificate
    197619A6600000
    7/8"-9
    1 7/16"55/64"ASTM Grade 8M
    ASTM A194
    Material Certificate
    197619A7700000
    1"-8
    1 5/8"63/64"ASTM Grade 8M
    ASTM A194
    Material Certificate
    197619A8800000
    1 1/8"-7
    1 13/16"1 9/64"ASTM Grade 8M
    ASTM A194
    Material Certificate
    197619A91000000
    1 1/8"-8
    1 13/16"1 9/64"ASTM Grade 8M
    ASTM A194
    Material Certificate
    197619A92000000
    1 1/4"-7
    2"1 1/4"ASTM Grade 8M
    ASTM A194
    Material Certificate
    197619A93000000
    1 1/4"-8
    2"1 1/4"ASTM Grade 8M
    ASTM A194
    Material Certificate
    197619A94000000
    1 1/2"-6
    2 3/8"1 1/2"ASTM Grade 8M
    ASTM A194
    Material Certificate
    197619A95000000
    1 1/2"-8
    2 3/8"1 1/2"ASTM Grade 8M
    ASTM A194
    Material Certificate
    197619A96000000
    1 5/8"-8
    2 9/16"1 5/8"ASTM Grade 8M
    ASTM A194
    Material Certificate
    197619A97000000
    1 3/4"-8
    2 3/4"1 3/4"ASTM Grade 8M
    ASTM A194
    Material Certificate
    197619A98000000
    2"-8
    3 1/8"2 1/64"ASTM Grade 8M
    ASTM A194
    Material Certificate
    197619A99000000
     

    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.
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Hex Nuts. 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
    5/16"-18
    1/2"17/64"ASTM Grade 8M
    ASTM A194
    595005A125000000
    3/8"-16
    9/16"21/64"ASTM Grade 8M
    ASTM A194
    195005A1300000
    1/2"-13
    3/4"7/16"ASTM Grade 8M
    ASTM A194
    Material Certificate
    195005A1350000
    5/8"-11
    15/16"35/64"ASTM Grade 8M
    ASTM A194
    Material Certificate
    195005A1400000
    3/4"-10
    1 1/8"41/64"ASTM Grade 8M
    ASTM A194
    Material Certificate
    195005A14500000
    1"-8
    1 1/2"55/64"ASTM Grade 8M
    ASTM A194
    Material Certificate
    195005A15000000
     

    Stainless Steel Heavy Hex Head Screw Kits for Metal Pipe Flanges

    Image of ProductInUse. Shown Installed. Front orientation. Hex Head Screws. Stainless Steel Heavy Hex Head Screw Kits for Metal Pipe Flanges.
    Image of Product. Front orientation. Hex Head Screws. Stainless Steel Heavy Hex Head Screw Kits for Metal Pipe Flanges.

    Shown Installed

    All the hardware you need to join aluminum or stainless steel pipe flanges. These kits come with corrosion-resistant screws and nuts in the right size and number to match your flange's bolt holes. With screw heads and nuts that are about 10% wider than standard, these kits handle heavier loads by distributing them over a larger area. The head also gives you six, flat contact points, so wrenches and sockets won't slip and round off the drive.
    Screw length is measured from under the head. For a tight seal, you’ll also need a gasket between the flanges.
    ASTM Grade B8M—Also known as pressure bolts, these screws meet ASTM standards for use in high-pressure and high-temperature applications. They're also good for cold temperatures.
    316 Stainless Steel—Superior to 18-8 stainless steel screws, these won't degrade when exposed to harsh weather, salt water, and most chemicals.
    Screw
    Nut
    316 Stainless Steel
    Screws and Nuts
    For Pipe
    Size
    Thread
    Size
    Lg.
    Head
    Wd.
    Head
    Ht.
    Threading
    Thread
    Spacing
    Tensile Strength,
    psi
    Wd.
    Ht.
    Includes
    Each
    ASTM Grade B8M for Class 125/150 Flanges
    1/2, 3/4
    1/2"-13
    2"7/8"11/32"Partially ThreadedCoarse
    75,0007/8"31/64"4 Heavy Hex Head Screws
    4 Heavy Hex Nuts
    97755A111000000
    1, 1 1/4
    1/2"-13
    2 1/4"7/8"11/32"Partially ThreadedCoarse
    75,0007/8"31/64"4 Heavy Hex Head Screws
    4 Heavy Hex Nuts
    97755A11400000
    1 1/2
    1/2"-13
    2 1/2"7/8"11/32"Partially ThreadedCoarse
    75,0007/8"31/64"4 Heavy Hex Head Screws
    4 Heavy Hex Nuts
    97755A12100000
    2
    5/8"-11
    2 3/4"1 1/16"27/64"Partially ThreadedCoarse
    75,0001 1/16"39/64"4 Heavy Hex Head Screws
    4 Heavy Hex Nuts
    97755A11500000
    2 1/2, 3
    5/8"-11
    3"1 1/16"27/64"Partially ThreadedCoarse
    75,0001 1/16"39/64"4 Heavy Hex Head Screws
    4 Heavy Hex Nuts
    97755A11200000
    3 1/2, 4
    5/8"-11
    3"1 1/16"27/64"Partially ThreadedCoarse
    75,0001 1/16"39/64"8 Heavy Hex Head Screws
    8 Heavy Hex Nuts
    97755A11600000
    5, 6
    3/4"-10
    3 1/4"1 1/4"1/2"Partially ThreadedCoarse
    75,0001 1/4"47/64"8 Heavy Hex Head Screws
    8 Heavy Hex Nuts
    97755A117000000
    8
    3/4"-10
    3 1/2"1 1/4"1/2"Partially ThreadedCoarse
    75,0001 1/4"47/64"8 Heavy Hex Head Screws
    8 Heavy Hex Nuts
    97755A11800000
     
    ASTM Grade B8M for Class 250/300 Flanges
    2
    5/8"-11
    3"1 1/16"27/64"Partially ThreadedCoarse
    75,0001 1/16"39/64"8 Heavy Hex Head Screws
    8 Heavy Hex Nuts
    97755A11300000
    3
    3/4"-10
    3 1/2"1 1/4"1/2"Partially ThreadedCoarse
    75,0001 1/4"47/64"8 Heavy Hex Head Screws
    8 Heavy Hex Nuts
    97755A11900000
     
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