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    49 Products

    Nylon-Insert Flange Nuts

    A nylon insert grips the screw for a stronger hold than a serrated flange, without damaging threads or marring the surface of your material. However, the insert may become brittle if exposed to high temperatures. These nuts have a flange that distributes pressure evenly across the mounting surface, so you don't need a separate washer. They are ideal for securing screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts. You can reuse them a handful of times, but their holding power will decrease with each use. Also known as collar nuts.
    High-Strength Steel
    Image of Product. Front orientation. Flange Nuts. Nylon-Insert Flange Nuts.
    Rated Grade 8, Grade G, or Class 10, these are about 25% stronger than medium-strength steel nuts. They are commonly used to fasten components in valves, pumps, and motors. 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.
    Black-Oxide Steel—Typically chosen for their appearance, these nuts have a dark, matte coating that creates a finished look. They offer minimal corrosion resistance, so they're best for dry environments.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Yellow-Chromate-Plated Steel
    1/4"-20
    7/16"19/64"0.56"0.04"ASME Grade G
    25010000000000000000
    5/16"-18
    1/2"11/32"0.68"0.05"ASME Grade G
    250500000000000000
    3/8"-16
    9/16"13/32"0.81"0.06"ASME Grade G
    2505000000000000000
    1/2"-13
    3/4"35/64"1.07"0.08"ASME Grade G
    2502500000000000000
    5/8"-11
    15/16"43/64"1.33"0.1"ASME Grade G
    2501000000000000000
     
    Black-Oxide Steel
    1/4"-20
    7/16"19/64"0.56"0.04"ASME Grade G
    25010000000000000000
    5/16"-18
    1/2"23/64"0.68"0.05"ASME Grade G
    25010000000000000000
    3/8"-16
    9/16"27/64"0.81"0.06"ASME Grade G
    2505000000000000000
    1/2"-13
    3/4"35/64"1.07"0.08"ASME Grade G
    2505000000000000000
    5/8"-11
    15/16"11/16"1.33"0.1"ASME Grade G
    2502500000000000000
    3/4"-10
    1 1/8"13/16"1.585"0.11"ASME Grade G
    2501000000000000000
     

    Distorted-Thread Flange Nuts

    The strongest hold of all the flange nuts we offer, these have irregularly shaped threads that grip the screw to resist loosening. The threads prevent the nut from backing out due to high vibration, but they also increase the effort to install and remove. To get these nuts off, you may need special tools, such as an impact wrench or propane torch, so they are not reusable. Nuts have a flange that distributes pressure evenly across the mounting surface without the need for a separate washer. They are ideal for securing screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts. Also known as collar nuts.
    High-Strength Steel
    Image of Product. Bottom orientation. Flange Nuts. Distorted-Thread Flange Nuts.
    Rated Grade 8, Grade G, or Class 10, these are about 25% stronger than medium-strength steel nuts. They are commonly used to fasten components in valves, pumps, and motors. 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.
    Black-Oxide Steel—Typically chosen for their appearance, these nuts have a dark, matte coating that creates a finished look. They offer minimal corrosion resistance, so they're best for dry environments.
    Black Phosphate-Coated Steel—The dark coating creates both a finished appearance and a barrier against rust that's more durable than clear zinc plating.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc-Yellow-Chromate-Plated Steel
    1/4"-20
    7/16"19/64"9/16"0.04"ASME Grade G
    50000000000000000
    1/4"-28
    7/16"19/64"9/16"0.04"ASME Grade G
    5000000000000000
    5/16"-18
    1/2"23/64"11/16"0.05"ASME Grade G
    2500000000000000
    5/16"-24
    1/2"23/64"11/16"0.05"ASME Grade G
    2500000000000000
    3/8"-16
    9/16"27/64"13/16"0.06"ASME Grade G
    2500000000000000
    3/8"-24
    9/16"27/64"13/16"0.06"ASME Grade G
    2500000000000000
    1/2"-13
    3/4"9/16"1 1/16"0.08"ASME Grade G
    100000000000000
    1/2"-20
    3/4"9/16"1 1/16"0.08"ASME Grade G
    1000000000000000
    5/8"-11
    15/16"11/16"1 21/64"0.1"ASME Grade G
    1000000000000000
    5/8"-18
    15/16"11/16"1 21/64"0.1"ASME Grade G
    1000000000000000
    3/4"-10
    1 1/8"13/16"1 37/64"0.11"ASME Grade G
    500000000000000
     
    Black-Oxide Steel
    1/4"-20
    7/16"19/64"9/16"0.04"ASME Grade G
    5000000000000000
    1/4"-28
    7/16"19/64"9/16"0.04"ASME Grade G
    5000000000000000
    5/16"-18
    1/2"23/64"11/16"0.05"ASME Grade G
    2500000000000000
    5/16"-24
    1/2"23/64"11/16"0.05"ASME Grade G
    2500000000000000
    3/8"-16
    9/16"27/64"13/16"0.06"ASME Grade G
    2500000000000000
    3/8"-24
    9/16"27/64"13/16"0.06"ASME Grade G
    2500000000000000
    1/2"-13
    3/4"9/16"1 1/16"0.08"ASME Grade G
    1000000000000000
    1/2"-20
    3/4"9/16"1 1/16"0.08"ASME Grade G
    1000000000000000
    5/8"-11
    15/16"11/16"1 21/64"0.1"ASME Grade G
    1000000000000000
    5/8"-18
    15/16"11/16"1 21/64"0.1"ASME Grade G
    1000000000000000
    3/4"-10
    1 1/8"13/16"1 37/64"0.11"ASME Grade G
    500000000000000
     
    Black Phosphate-Coated Steel
    1/4"-20
    7/16"19/64"9/16"0.04"ASME Grade G
    1000000000000000
    1/4"-28
    7/16"19/64"9/16"0.04"ASME Grade G
    1000000000000000
    5/16"-18
    1/2"23/64"11/16"0.05"ASME Grade G
    10000000000000000
    5/16"-24
    1/2"23/64"11/16"0.05"ASME Grade G
    10000000000000000
    3/8"-16
    9/16"27/64"13/16"0.06"ASME Grade G
    5000000000000000
    3/8"-24
    9/16"27/64"13/16"0.06"ASME Grade G
    2500000000000000
    1/2"-13
    3/4"9/16"1 1/16"0.08"ASME Grade G
    2500000000000000
    1/2"-20
    3/4"9/16"1 1/16"0.08"ASME Grade G
    250000000000000
    5/8"-11
    15/16"11/16"1 21/64"0.1"ASME Grade G
    1000000000000000
    5/8"-18
    15/16"11/16"1 21/64"0.1"ASME Grade G
    100000000000000
    3/4"-10
    1 1/8"53/64"1 37/64"0.11"ASME Grade G
    1000000000000000
    3/4"-16
    1 1/8"53/64"1 37/64"0.11"ASME Grade G
    100000000000000
    7/8"-9
    1 5/16"51/64"1 3/4"0.12"ASME Grade G
    500000000000000
    7/8"-14
    1 5/16"51/64"1 3/4"0.12"ASME Grade G
    500000000000000
    1"-8
    1 1/2"57/64"2 1/16"0.13"ASME Grade G
    500000000000000
    1"-14
    1 1/2"57/64"2 1/16"0.13"ASME Grade G
    500000000000000
     
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