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    57 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 Flanges
    Image of Product. Front. Front orientation. Pipe and Fittings. Low-Pressure Iron and Steel Threaded Pipe Flanges, Forged Flanges, Threaded Fitting Connection, Female, Flanged Fitting Connection, Raised Surface.
    Image of Product. Raised Surface on Back. Back orientation. Pipe and Fittings. Low-Pressure Iron and Steel Threaded Pipe Flanges, Forged Flanges, Threaded Fitting Connection, Female, Flanged Fitting Connection, Raised Surface.

    Front

    Raised

    Surface on

    Back

    Forged flanges have better strength than cast flanges.
    Pipe
    Size
    Bolt
    Hole
    (A)
    (B)
    Flanged Connection
    Surface (B)
    Flange
    OD
    For Bolt
    Dia.
    Dia.
    No.
    Of
    Bolt Circle
    Dia.
    Pressure
    Class
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    BSPT Female
    1/2
    		1/2
    		Raised3 1/2"1/2"5/8"42 3/8"150
    		Steel
    		285 psi @ 72° F230 psi @ 300° F8128K11000000
    3/4
    		3/4
    		Raised3 7/8"1/2"5/8"42 3/4"150
    		Steel
    		285 psi @ 72° F230 psi @ 300° F8128K1200000
    1
    		1
    		Raised4 1/4"1/2"5/8"43 1/8"150
    		Steel
    		285 psi @ 72° F230 psi @ 300° F8128K1300000
    1 1/4
    		1 1/4
    		Raised4 5/8"1/2"5/8"43 1/2"150
    		Steel
    		285 psi @ 72° F230 psi @ 300° F8128K1400000
    1 1/2
    		1 1/2
    		Raised5"1/2"5/8"43 7/8"150
    		Steel
    		285 psi @ 72° F230 psi @ 300° F8128K1500000
    2
    		2
    		Raised6"5/8"3/4"44 3/4"150
    		Steel
    		285 psi @ 72° F230 psi @ 300° F8128K16000000
    2 1/2
    		2 1/2
    		Raised7"5/8"3/4"45 1/2"150
    		Steel
    		285 psi @ 72° F230 psi @ 300° F8128K17000000
    3
    		3
    		Raised7 1/2"5/8"3/4"46"150
    		Steel
    		285 psi @ 72° F230 psi @ 300° F8128K18000000
    4
    		4
    		Raised9"5/8"3/4"87 1/2"150
    		Steel
    		285 psi @ 72° F230 psi @ 300° F8128K21000000
    6
    		6
    		Raised11"3/4"7/8"89 1/2"150
    		Steel
    		285 psi @ 72° F230 psi @ 300° F8128K23000000
     

    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 Flanges
    Image of Product. Front. Front orientation. Pipe and Fittings. Low-Pressure Stainless Steel Threaded Pipe Flanges, Forged Flanges, Threaded Fitting Connection, Female, Flanged Fitting Connection, Raised Surface.
    Image of Product. Raised Surface on Back. Back orientation. Pipe and Fittings. Low-Pressure Stainless Steel Threaded Pipe Flanges, Forged Flanges, Threaded Fitting Connection, Female, Flanged Fitting Connection, Raised Surface.

    Front

    Raised

    Surface on

    Back

    Forged flanges have better strength than cast flanges.
    304/304L Stainless Steel—Flanges hold up in humid, damp, and washdown environments but will corrode if exposed to salt water or chemicals.
    Pipe
    Size
    Bolt
    Hole
    304/304L
    Stainless Steel
    (A)
    (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
    BSPT Female
    1/2
    		1/2
    		Raised3 1/2"1/2"0.62"42 3/8"150
    		230 psi @ 72° F150 psi @ 360° F1384N11000000
    3/4
    		3/4
    		Raised3 7/8"1/2"0.62"42 3/4"150
    		230 psi @ 72° F150 psi @ 360° F1384N1200000
    1
    		1
    		Raised4 1/4"1/2"0.62"43 1/8"150
    		230 psi @ 72° F150 psi @ 360° F1384N1300000
    2
    		2
    		Raised6"5/8"0.75"44 3/4"150
    		230 psi @ 72° F150 psi @ 360° F1384N15000000
     

    Low-Pressure Brass and Bronze Threaded Pipe Flanges

    Also known as Pressure Class 150 flanges, these are designed for low-pressure applications. Bolt two same-size flanges together with a gasket (sold separately) to create an access point within a line. Flanges have good corrosion resistance. To adhere to safety standards for drinking water systems, use flanges that meet NSF/ANSI 61.
    Flanges
    Image of Product. Front. Front orientation. Pipe and Fittings. Low-Pressure Brass and Bronze Threaded Pipe Flanges, Flanges, Threaded Fitting Connection, Female, Flanged Fitting Connection, Flat Surface.
    Image of Product. Flat Surface on Back. Back orientation. Pipe and Fittings. Low-Pressure Brass and Bronze Threaded Pipe Flanges, Flanges, Threaded Fitting Connection, Female, Flanged Fitting Connection, Flat Surface.

    Front

    Flat Surface

    on Back

    Pipe
    Size
    Bolt
    Hole
    (A)
    (B)
    Flanged Connection
    Surface (B)
    Flange
    OD
    For Bolt
    Dia.
    Dia.
    No.
    Of
    Bolt Circle
    Dia.
    Pressure
    Class
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    BSPT Female
    1/2
    		1/2
    		Flat3 1/2"1/2"5/8"42 3/8"150
    		Bronze200 psi @ 72° F125 psi @ 400° F4978K194000000
    3/4
    		3/4
    		Flat3 7/8"1/2"5/8"42 3/4"150
    		Bronze200 psi @ 72° F125 psi @ 400° F4978K19500000
    1
    		1
    		Flat4 1/4"1/2"5/8"43 1/8"150
    		Bronze200 psi @ 72° F125 psi @ 400° F4978K196000000
    1 1/2
    		1 1/2
    		Flat5"1/2"5/8"43 7/8"150
    		Bronze200 psi @ 72° F125 psi @ 400° F4978K198000000
    2
    		2
    		Flat6"5/8"3/4"44 3/4"150
    		Bronze200 psi @ 72° F125 psi @ 400° F4978K199000000
     

    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 Connectors
    Image of Product. Female. Front orientation. Pipe and Fittings. Low-Pressure Aluminum Threaded Pipe Fittings, Straight Connectors, Threaded Fitting Connection, Female.

    Female

    Pipe
    Size
    Material
    Max. Pressure
    @ Temp.
    Each
    BSPT Female
    1/8
    		6061 Aluminum250 psi @ 72° F2617K3700000
    1/4
    		6061 Aluminum250 psi @ 72° F2617K380000
    3/8
    		6061 Aluminum250 psi @ 72° F2617K390000
    1/2
    		6061 Aluminum250 psi @ 72° F2617K4100000
    3/4
    		6061 Aluminum250 psi @ 72° F2617K4200000
    1
    		6061 Aluminum250 psi @ 72° F2617K4300000
    1 1/2
    		6061 Aluminum250 psi @ 72° F2617K4400000
    2
    		6061 Aluminum250 psi @ 72° F2617K4500000
     
    Straight Adapters
    Image of Product. Threaded Female × Threaded Male. Front orientation. Pipe and Fittings. Low-Pressure Aluminum Threaded Pipe Fittings, Straight Adapters, Male, Female, Threaded Fitting Connection, Hex Body.

    Threaded Female ×

    Threaded Male

    Pipe
    Size
    (A)
    (B)
    Body
    Shape
    Material
    Max. Pressure
    @ Temp.
    Each
    NPT Female × BSPT Male
    1/8
    		1/8
    		Hex6061 Aluminum150 psi @ 72° F1527N14000000
    1/4
    		1/4
    		Hex6061 Aluminum150 psi @ 72° F1527N1500000
    3/8
    		3/8
    		Hex6061 Aluminum150 psi @ 72° F1527N1600000
    1/2
    		1/2
    		Hex6061 Aluminum150 psi @ 72° F1527N1700000
    3/4
    		3/4
    		Hex6061 Aluminum150 psi @ 72° F1527N1800000
     
    BSPT Female × NPT Male
    1/8
    		1/8
    		Hex6061 Aluminum150 psi @ 72° F1527N100000
    1/4
    		1/4
    		Hex6061 Aluminum150 psi @ 72° F1527N200000
    3/8
    		3/8
    		Hex6061 Aluminum150 psi @ 72° F1527N300000
    1/2
    		1/2
    		Hex6061 Aluminum150 psi @ 72° F1527N400000
    3/4
    		3/4
    		Hex6061 Aluminum150 psi @ 72° F1527N500000
    1
    		1
    		Hex6061 Aluminum150 psi @ 72° F1527N600000
     
    Bushing Straight Reducing Adapters
    Image of Product. Male × Female. Front orientation. Contains Annotated. Pipe and Fittings. Low-Pressure Aluminum Threaded Pipe Fittings, Bushing Straight Reducing Adapters, Female, Male, Threaded Fitting Connection, Hex Body.

    Male × Female

    Pipe
    Size
    (A)
    (B)
    Body
    Shape
    Material
    Max. Pressure
    @ Temp.
    Each
    BSPT Male × BSPT Female
    1/4
    		1/8
    		Hex6061 Aluminum250 psi @ 72° F2617K5500000
    3/8
    		1/4
    		Hex6061 Aluminum250 psi @ 72° F2617K5600000
    1/2
    		1/4
    		Hex6061 Aluminum250 psi @ 72° F2617K5800000
    1/2
    		3/8
    		Hex6061 Aluminum250 psi @ 72° F2617K5700000
    3/4
    		1/2
    		Hex6061 Aluminum250 psi @ 72° F2617K5900000
    1
    		3/4
    		Hex6061 Aluminum250 psi @ 72° F2617K6100000
    1 1/2
    		1
    		Hex6061 Aluminum250 psi @ 72° F2617K6200000
    2
    		1 1/2
    		Hex6061 Aluminum250 psi @ 72° F2617K6300000
     
    180° Bend Connectors
    Image of Product. Front orientation. Pipe Traps. Low-Pressure Aluminum Threaded Pipe Fittings.
    180° bend connectors are also known as U-bends.
    Pipe
    Size
    Material
    Max. Pressure
    @ Temp.
    Shape
    Each
    NPT Female
    1/2
    		356 Aluminum150 psi @ 72° F180° Bend44705K479000000
    3/4
    		356 Aluminum150 psi @ 72° F180° Bend44705K48100000
    1
    		356 Aluminum150 psi @ 72° F180° Bend44705K48200000
     
    Locknuts
    Image of Product. Front orientation. Pipe Locknuts.
    NPSL Thread—NPSL (National Pipe Straight Locknut) threads are compatible with NPT threads.
    Pipe
    Size
    Finished
    Material
    Max. Pressure
    @ Temp.
    Each
    NPSL Female
    1/4
    		6061 Aluminum150 psi @ 72° F44705K41200000
    3/8
    		6061 Aluminum150 psi @ 72° F44705K4130000
    1/2
    		356 Aluminum150 psi @ 72° F44705K4140000
    3/4
    		356 Aluminum150 psi @ 72° F44705K41500000
    1
    		356 Aluminum150 psi @ 72° F44705K41600000
     

    Plastic Pipe Locknuts for Oil

    Image of Product. Front orientation. Pipe Locknuts. Plastic Pipe Locknuts for Oil.
    Made of corrosion-resistant plastic, these locknuts won’t deteriorate when used in oil applications. They also have high strength and impact resistance. Apply a non-hardening, plastic-compatible sealant to the male threads to prevent leaks. Tape or sealants with PTFE are not recommended for plastic-to-plastic threaded connections. When making a threaded connection be careful not to overtighten the threads. To prevent cracks and leaks, finger tighten the locknut, then wrench-tighten one to two turns.
    Warning: Never use plastic pipe locknuts and pipe with compressed air or gas.
    Pipe Locknuts
    Thread Sealants
    Pipe
    Size
    Lg.
    Thread
    Direction
    Color
    Max. Pressure
    @ Temp.
    For Use
    With
    Temp. Range,
    ° F
    Material
    Each
    Each
    BSPT Female
    1/2
    		29/64"Right Hand
    		White200 psi @ 72° FOil0 to 230Nylon3736K111000004586K9000000
     

    Low-Pressure Galvanized Iron and Steel Threaded Pipe Flanges

    The galvanized finish on these flanges provides fair corrosion resistance. Also known as Pressure Class 150 flanges, they are for use in low-pressure applications. Bolt two same-size flanges together with a gasket (sold separately) to create an access point within a line.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Flanges
    Image of Product. Front. Front orientation. Pipe and Fittings. Low-Pressure Galvanized Iron and Steel Threaded Pipe Flanges, Flanges, Threaded Fitting Connection, Female, Flanged Fitting Connection, Raised Surface.
    Image of Product. Raised Surface on Back. Back orientation. Pipe and Fittings. Low-Pressure Galvanized Iron and Steel Threaded Pipe Flanges, Flanges, Threaded Fitting Connection, Female, Flanged Fitting Connection, Raised Surface.

    Front

    Raised

    Surface on

    Back

    Pipe
    Size
    Bolt
    Hole
    (A)
    (B)
    Flanged Connection
    Surface (B)
    Flange
    OD
    For Bolt
    Dia.
    Dia.
    No.
    Of
    Bolt Circle
    Dia.
    Pressure
    Class
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    BSPT Female
    2
    		2
    		Raised6"3/4"3/4"44 3/4"150
    		Galvanized Steel285 psi @ 72° F150 psi @ 300° F1584N50000000
     
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