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    10 Products
    About Pipe and Fittings
    industrial info icon

    Measure your pipe and fittings to identify their pipe size, thread size, schedule, and thread type. Then, find compatible components.

    Low-Pressure Iron and Steel Threaded Pipe Flanges

    Use these flanges for low-pressure applications in noncorrosive environments. Bolt two flanges of the same size together with a gasket (sold separately) to create an access point within a line.
    Forged Reducing Flanges
    Image of ProductInUse. Reducing Flange. Side1 orientation. Contains Annotated. Pipe and Fittings. Low-Pressure Iron and Steel Threaded Pipe Flanges, Forged Reducing Flanges, Female, Flanged Fitting Connection, Threaded Fitting Connection, Raised Surface.
    Image of Product. Raised Surface on Back. Front orientation. Pipe and Fittings. Low-Pressure Iron and Steel Threaded Pipe Flanges, Forged Reducing Flanges, Female, Flanged Fitting Connection, Threaded Fitting Connection, Raised Surface.
    Image of Product. Front. Front orientation. Pipe and Fittings. Low-Pressure Iron and Steel Threaded Pipe Flanges, Forged Reducing Flanges, Female, Flanged Fitting Connection, Threaded Fitting Connection, Raised Surface.

    Reducing

    Flange

    Raised

    Surface on

    Back

    Front

    Forged flanges have better strength than cast flanges.
    Reducing flanges allow you to transition your system to a smaller pipe size; attach to a flange with a larger pipe size but with the same flange dimensions.
    Bolt
    Hole
    Pipe Size
    (A)
    For Flange
    Pipe Size (B)
    Flanged Connection
    Surface (B)
    Flange
    OD
    For Bolt
    Dia.
    Dia.
    No.
    Of
    Bolt Circle
    Dia.
    Pressure
    Class
    Material
    Max. Pressure
    @ Temp.
    Each
    NPT Female
    1/4
    1
    Raised4 1/4"1/2"5/8"43.12"150
    Steel
    Not Rated1802N11000000
     

    Low-Pressure Stainless Steel Threaded Pipe Flanges

    Also known as Pressure Class 150 flanges, these are designed for low-pressure pipe applications. Bolt two flat-surface flanges or two raised-surface flanges of the same size together with a gasket (sold separately) to create an access point within a line.
    Forged Reducing Flanges
    Image of ProductInUse. Reducing Flange. Side1 orientation. Contains Annotated. Pipe and Fittings. Low-Pressure Stainless Steel Threaded Pipe Flanges, Forged Reducing Flanges, Female, Flanged Fitting Connection, Threaded Fitting Connection, Raised Surface.
    Image of Product. Front. Front orientation. Pipe and Fittings. Low-Pressure Stainless Steel Threaded Pipe Flanges, Forged Reducing Flanges, Female, Flanged Fitting Connection, Threaded Fitting Connection, Raised Surface.
    Image of Product. Raised Surface on Back. Back orientation. Pipe and Fittings. Low-Pressure Stainless Steel Threaded Pipe Flanges, Forged Reducing Flanges, Female, Flanged Fitting Connection, Threaded Fitting Connection, Raised Surface.

    Reducing

    Flange

    Front

    Raised

    Surface on

    Back

    Forged flanges have better strength than cast flanges.
    Reducing flanges allow you to transition your system to a smaller pipe size; attach to a flange with a larger pipe size but with the same flange dimensions.
    304/304L Stainless Steel—Flanges hold up in humid, damp, and washdown environments but will corrode if exposed to salt water or chemicals.
    316/316L Stainless Steel—Flanges are the most corrosion resistant. They stand up to wet environments, just like 304 stainless steel flanges, but unlike 304 stainless steel, they will not corrode from salt water, chlorine solutions, and chemicals.
    Bolt
    Hole
    304/304L
    Stainless Steel
    316/316L
    Stainless Steel
    Pipe Size
    (A)
    For Flange
    Pipe Size (B)
    Flanged Connection
    Surface (B)
    Flange
    OD
    For Bolt
    Dia.
    Dia.
    No.
    Of
    Bolt Circle
    Dia.
    Pressure
    Class
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    Each
    NPT Female
    1/4
    1
    Raised4 1/4"1/2"0.62"43 1/8"150
    230 psi @ 72° F150 psi @ 360° F44685K33100000044695K26000000
     

    Low-Pressure Iron and Steel Threaded Pipe Fittings

    Use these fittings for low-pressure applications in noncorrosive environments.
    Straight Adapters for Tanks
    Image of Product. Female × Butt Weld (For Flat Surface). Front orientation. Pipe and Fittings. Low-Pressure Iron and Steel Threaded Pipe Fittings, Straight Adapters for Tanks, Threaded Fitting Connection, Butt-Weld Fitting Connection, Female, For Flat Tank Surfaces.

    Female × Butt Weld

    (For Flat Surface)

    Fittings for tanks create an inlet or outlet connection on the surface of any tank, pressure vessel, or drum.
    Threaded Fitting Connection—Threaded female x butt weld straight adapters are also known as half couplings.
    Pipe
    Size
    For Hole
    Diameter (B)
    OD
    For Tank
    Surface (B)
    Material
    Max. Pressure
    @ Temp.
    Each
    NPT Female × Butt Weld
    1/4
    3/4"1 1/4"FlatCarbon SteelNot Rated12555K5100000
     
    Straight Adapters with Extension for Tanks
    Image of Product. Female × Butt Weld. Front orientation. Pipe and Fittings. Low-Pressure Iron and Steel Threaded Pipe Fittings, Straight Adapters with Extension for Tanks, Threaded Fitting Connection, Butt-Weld Fitting Connection, Female, For Flat Tank Surfaces.

    Female × Butt Weld

    Fittings for tanks create an inlet or outlet connection on the surface of any tank, pressure vessel, or drum.
    Adapters with extension fit tightly into the hole, which keeps the fitting steady during welding.
    Threaded Fitting Connection—Threaded female x butt weld straight adapters are also known as half couplings.
    Pipe
    Size
    For Hole
    Diameter (B)
    OD
    For Tank
    Surface (B)
    Material
    Max. Pressure
    @ Temp.
    Each
    NPT Female × Butt Weld
    1/4
    15/16"1 5/16"FlatCarbon SteelNot Rated12555K8100000
    1/4
    15/16"1 1/2"FlatCarbon SteelNot Rated12555K710000
     

    Low-Pressure Stainless Steel Threaded Pipe Fittings

    Use these fittings in a low-pressure pipe line.
    Straight Adapters with Extension for Tanks
    Image of Product. Female × Butt Weld. Front orientation. Pipe and Fittings. Low-Pressure Stainless Steel Threaded Pipe Fittings, Straight Adapters with Extension for Tanks, Threaded Fitting Connection, Butt-Weld Fitting Connection, Female, For Flat Tank Surfaces.

    Female × Butt Weld

    Fittings for tanks create an inlet or outlet connection on the surface of any tank, pressure vessel, or drum.
    Adapters with extension fit tightly into the hole, which keeps the fitting steady during welding.
    Threaded Fitting Connection—Threaded female x butt weld straight adapters are also known as half couplings.
    316 Stainless Steel—Fittings are the most corrosion resistant. They stand up to wet environments, just like 304 stainless steel fittings, but unlike 304 stainless steel, they will not corrode from salt water, chlorine solutions, and chemicals.
    316 Stainless Steel
    Pipe
    Size
    For Hole
    Diameter (B)
    OD
    For Tank
    Surface (B)
    Max. Pressure
    @ Temp.
    Each
    NPT Female × Butt Weld
    1/4
    15/16"1 1/2"FlatNot Rated1145K51000000
     

    Spin-Weld Plastic Pipe Fittings for Water

    Image of ProductInUse. Front orientation. Pipe and Fittings. Spin-Weld Plastic Pipe Fittings for Water.
    Create a leak-free, durable connection in plastic tanks, walls, or panels without gaskets or sealants. As you spin these fittings with a handheld electric router, they melt into the surface of your tank for a seal without any joints. To hold these fittings in your router, you’ll need the installation tool (sold separately). For proper installation, you’ll want to use a hole saw to drill a hole that matches the For Hole Diameter listed and check that your router meets the speed and power requirements shown in the table.
    To prevent leaks in threaded connections, apply a sealant to the male threads. Threaded connections can be taken apart as needed for maintenance and repair. For metal threads, use PTFE tape. For plastic threads, apply a non-hardening, plastic-compatible sealant. Tape or sealants with PTFE are not recommended for plastic-to-plastic connections. When making a threaded connection be careful not to overtighten the threads. To prevent cracks and leaks, finger tighten the fitting, then wrench-tighten one to two turns.
    Through-Wall Straight Adapters for Tanks
    Image of Product. Front orientation. Pipe and Fittings. Spin-Weld Plastic Pipe Fittings for Water, Through-Wall Straight Adapters for Tanks.
    Through-wall fittings are also known as bulkhead couplings; they mount through your wall or tank to create an inlet or outlet. When installing, the gasket should be on the inside of the wall.
    Fittings for tanks create an inlet or outlet connection on the surface of any tank, pressure vessel, or drum.
    Threaded Fitting Connection—Threaded female x butt weld straight adapters are also known as half couplings.
    Pipe
    Size
    For Hole
    Diameter (B)
    For Tank
    Surface (B)
    Material
    Color
    Each
    NPT Female × Butt Weld
    1/4
    0.88"FlatLDPEWhite4526N1100000
     
    Installation Tools
    Image of Product. Front orientation. Spin-Weld Installation Tools.
    For Pipe
    Size
    Shank
    Dia.
    Overall
    Lg.
    Material
    Shank
    Type
    For Tool
    Type
    Each
    For Pipe Connection
    1/4
    1/4"1 5/8"Aluminum
    RoundHand Router4526N10000000
     

    Low-Pressure Aluminum Threaded Pipe Fittings

    In addition to being lightweight, these aluminum fittings offer good corrosion resistance. Use them in low-pressure flow applications. To prevent cracking, do not tighten more than a 1/4-turn past hand tight.
    Straight Adapters with Extension for Tanks
    Image of Product. NPT Female × Butt Weld. Front orientation. Pipe and Fittings. Low-Pressure Aluminum Threaded Pipe Fittings, Straight Adapters with Extension for Tanks, Threaded Fitting Connection, Butt-Weld Fitting Connection, Female, For Flat Tank Surfaces.

    NPT Female × Butt

    Weld

    Fittings for tanks create an inlet or outlet connection on the surface of any tank, pressure vessel, or drum.
    Adapters with extension fit tightly into the hole, which keeps the fitting steady during welding.
    Threaded Fitting Connection—Threaded female x butt weld straight adapters are also known as half couplings.
    Pipe
    Size
    For Hole
    Diameter (B)
    OD
    For Tank
    Surface (B)
    Material
    Max. Pressure
    @ Temp.
    Each
    NPT Female × Butt Weld
    1/4
    7/8"1 5/16"Flat6061 AluminumNot Rated8694T42000000
     
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