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    38 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.

    High-Pressure Stainless Steel Unthreaded Pipe Flanges

    These heavy duty forged flanges create an access point in a high-pressure pipeline. Bolt two flat-surface flanges or two raised-surface flanges of the same size together with a gasket (not included). Flanges are made of stainless steel for excellent corrosion resistance.
    Forged Flanges
    Image of System. Stub End with Straight Adapter (Front). Front orientation. Pipe and Fittings. High-Pressure Stainless Steel Unthreaded Pipe Flanges, Forged Flanges, Stub End, Flat Surface.

    Stub End with

    Straight Adapter

    (Front)

    Image of Product. Butt Weld. Front orientation. Pipe and Fittings. High-Pressure Stainless Steel Unthreaded Pipe Flanges, Forged Flanges, Butt Weld, Raised Surface.
    Image of Product. Slip-On. Front orientation. Pipe and Fittings. High-Pressure Stainless Steel Unthreaded Pipe Flanges, Forged Flanges, Slip-On Weld Female, Raised Surface.
    Image of Product. Socket-Connect. Front orientation. Contains Annotated. Pipe and Fittings. High-Pressure Stainless Steel Unthreaded Pipe Flanges, Forged Flanges, Socket-Connect Female, Raised Surface.

    Butt Weld

    Slip-On

    Socket-Connect

    Forged flanges have better strength than cast flanges.
    Butt-Weld Fitting Connection—Butt-weld flanges are also known as weld-neck flanges; the flange neck has a beveled end that, when flush to pipe, creates a trough for a strong weld.
    Slip-on-Weld Fitting Connection—Slip-on weld flanges have no internal stop; slide a pipe through the flange and weld on both sides.
    Stub-End Fitting Connection—Stub-end flanges are also known as lap-joint flanges. Use them with a stub-end straight adapter (not included). The stub-end straight adapter slides into the flange and welds to pipe (not the flange). Since the flange isn’t welded to the pipe, it can be disconnected easily for frequent cleaning and inspecting.
    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.
    Pipe
    Size
    Dash
    Size
    Bolt
    Hole
    304/304L
    Stainless Steel
    316/316L
    Stainless Steel
    (A)
    (B)
    (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
    Each
    Butt Weld
    334848Raised8 1/4"3/4"0.875"86 5/8"300
    		600 psi @ 72° F415 psi @ 360° F4448T29400000004452T3140000000
    334848Raised8 1/4"3/4"0.88"86 5/8"600
    		1,200 psi @ 72° F825 psi @ 400° F———01503N38000000
     
    Slip-On Weld Female
    334848Raised8 1/4"3/4"0.875"86 5/8"300
    		600 psi @ 72° F300 psi @ 360° F4448T2580000004452T268000000
    334848Raised8 1/4"3/4"0.88"86 5/8"600
    		1,200 psi @ 72° F840 psi @ 400° F1538N23000000———0
     
    Socket-Connect Female
    334848Raised8 1/4"3/4"0.875"86 5/8"300
    		600 psi @ 72° F300 psi @ 360° F4448T2720000004452T282000000
    334848Raised8 1/4"3/4"0.88"86 5/8"600
    		1,200 psi @ 72° F840 psi @ 400° F1538N43000000———0
     
    Stub End
    334848Flat8 1/4"3/4"0.875"86 5/8"300
    		600 psi @ 72° F300 psi @ 360° F4448T3150000004452T325000000
     
    Forged Blind Flanges
    Image of Product. Front. Front orientation. Pipe and Fittings. High-Pressure Stainless Steel Unthreaded Pipe Flanges, Forged Blind Flanges, Flanged, Raised.
    Image of Product. Raised Surface on Back. Back orientation. Pipe and Fittings. High-Pressure Stainless Steel Unthreaded Pipe Flanges, Forged Blind Flanges, Flanged, Raised.

    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.
    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
    Dash
    Size
    Flanged Connection
    Surface
    Flange
    OD
    For Bolt
    Dia.
    Dia.
    No.
    Of
    Bolt Circle
    Dia.
    Pressure
    Class
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    Each
    Flanged
    348Raised8 1/4"3/4"0.875"86 5/8"300
    		600 psi @ 72° F300 psi @ 360° F4448T28300000004452T2930000000
    348Raised8 1/4"3/4"0.88"86 5/8"600
    		1,200 psi @ 72° F840 psi @ 400° F1538N980000001503N58000000
     
    Stub-End Straight Adapters
    Image of Product. Straight Adapter. Front orientation. Pipe Stub Ends. High-Pressure Stainless Steel Unthreaded Pipe Flanges.

    Straight Adapter

    Stub-end straight adapters are used with flanges. Slide a flange onto the stub end and weld the stub end to pipe (not the flange). Since the flange isn’t welded to the pipe, it can be disconnected easily, which creates an access point for frequent cleaning and inspecting.
    304/304L
    Stainless Steel
    316/316L
    Stainless Steel
    Pipe
    Size
    Wall
    Thk.
    Flange
    OD
    Construction
    Pipe
    Schedule
    Each
    Each
    30.216"5"Welded4045605K66100000045555K661000000

    High-Pressure Iron and Steel Unthreaded Pipe Flanges

    Forged for extra strength, these heavy duty flanges create an access point in high-pressure lines. To connect, bolt two flat-surface flanges or two raised-surface flanges of the same size together with a gasket (not included). Flanges are made of steel and best for noncorrosive environments.
    Forged Flanges
    Image of Product. Butt Weld (Front). Front orientation. Pipe and Fittings. High-Pressure Iron and Steel Unthreaded Pipe Flanges, Forged Flanges, Butt Weld, Raised Surface.
    Image of Product. Butt Weld (Raised Surface on Back). Back orientation. Pipe and Fittings. High-Pressure Iron and Steel Unthreaded Pipe Flanges, Forged Flanges, Butt Weld, Raised Surface.
    Image of Product. Slip-On Weld (Front). Front orientation. Pipe and Fittings. High-Pressure Iron and Steel Unthreaded Pipe Flanges, Forged Flanges, Slip-On Weld Female, Raised Surface.
    Image of Product. Slip-On Weld (Raised Surface on Back). Front orientation. Pipe and Fittings. High-Pressure Iron and Steel Unthreaded Pipe Flanges, Forged Flanges, Slip-On Weld Female, Raised Surface.

    Butt Weld

    (Front)

    Butt Weld

    (Raised Surface

    on Back)

    Slip-On Weld

    (Front)

    Slip-On Weld

    (Raised

    Surface on

    Back)

    Image of Product. Socket Connect (Front). Front orientation. Contains Annotated. Pipe and Fittings. High-Pressure Iron and Steel Unthreaded Pipe Flanges, Forged Flanges, Socket-Connect Female, Raised Surface.
    Image of Product. Socket-Connect (Raised Surface on Back). Back orientation. Pipe and Fittings. High-Pressure Iron and Steel Unthreaded Pipe Flanges, Forged Flanges, Socket-Connect Female, Raised Surface.
    Image of Product. Stub-End (Front). Front orientation. Contains Annotated. Pipe and Fittings. High-Pressure Iron and Steel Unthreaded Pipe Flanges, Forged Flanges, Stub-End Female, Flat Surface.
    Image of Product. Stub-End (Flat Surface on Back). Back orientation. Pipe and Fittings. High-Pressure Iron and Steel Unthreaded Pipe Flanges, Forged Flanges, Stub-End Female, Flat Surface.

    Socket Connect (Front)

    Socket-Connect

    (Raised

    Surface on

    Back)

    Stub-End (Front)

    Stub-End (Flat

    Surface on

    Back)

    Forged flanges have better strength than cast flanges.
    Butt-Weld Fitting Connection—Butt-weld flanges are also known as weld-neck flanges; the flange neck has a beveled end that, when flush to pipe, creates a trough for a strong weld.
    Slip-on-Weld Fitting Connection—Slip-on weld flanges have no internal stop; slide a pipe through the flange and weld on both sides.
    Stub-End Fitting Connection—Stub-end flanges are also known as lap-joint flanges. Use them with a stub-end straight adapter (not included). The stub-end straight adapter slides into the flange and welds to pipe (not the flange). Since the flange isn’t welded to the pipe, it can be disconnected easily for frequent cleaning and inspecting.
    Pipe
    Size
    Dash
    Size
    Bolt
    Hole
    (A)
    (B)
    (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
    Butt Weld
    334848Raised8 1/4"3/4"7/8"86 5/8"300
    		Steel
    		600 psi @ 72° F300 psi @ 300° F6806K314000000
    334848Raised8 1/4"0.88"0.88"86.62"600
    		Steel
    		1,400 psi @ 72° F1,300 psi @ 300° F6806K45200000
     
    Slip-On Weld Female
    334848Raised8 1/4"3/4"7/8"86 5/8"300
    		Steel
    		600 psi @ 72° F300 psi @ 300° F6806K28400000
    334848Raised8 1/4"0.88"0.88"86.62"600
    		Steel
    		1,400 psi @ 72° F1,300 psi @ 300° F6806K43800000
     
    Socket-Connect Female
    334848Raised8 1/4"3/4"7/8"86 5/8"300
    		Steel
    		600 psi @ 72° F300 psi @ 300° F6806K29400000
    334848Raised8 1/4"0.88"0.88"86.62"600
    		Steel
    		1,400 psi @ 72° F1,300 psi @ 300° F6806K43200000
     
    Stub-End Female
    334848Flat8 1/4"3/4"7/8"86 5/8"300
    		Steel
    		600 psi @ 72° F300 psi @ 300° F6806K33400000
     
    Forged Blind Flanges
    Image of Product. Front. Front orientation. Pipe and Fittings. High-Pressure Iron and Steel Unthreaded Pipe Flanges, Forged Blind Flanges, Flanged, Raised.
    Image of Product. Raised Surface on Back. Back orientation. Pipe and Fittings. High-Pressure Iron and Steel Unthreaded Pipe Flanges, Forged Blind Flanges, Flanged, Raised.

    Front

    Raised

    Surface on

    Back

    Forged flanges have better strength than cast flanges.
    Bolt
    Hole
    Pipe
    Size
    Dash
    Size
    Flanged Connection
    Surface
    Flange
    OD
    For Bolt
    Dia.
    Dia.
    No.
    Of
    Bolt Circle
    Dia.
    Pressure
    Class
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    Flanged
    348Raised8 1/4"3/4"7/8"86 5/8"300
    		Steel
    		600 psi @ 72° F300 psi @ 300° F6806K324000000
    348Raised8 1/4"0.88"0.88"86.62"600
    		Steel
    		1,400 psi @ 72° F1,300 psi @ 300° F6806K45800000
     
    Stub-End Straight Adapters
    Image of Product. Straight Adapter. Front orientation. Pipe Stub Ends. High-Pressure Iron and Steel Unthreaded Pipe Flanges.

    Straight Adapter

    Stub-end straight adapters are used with flanges. Slide a flange onto the stub end and weld the stub end to pipe (not the flange). Since the flange isn’t welded to the pipe, it can be disconnected easily, which creates an access point for frequent cleaning and inspecting.
    Pipe
    Size
    Flange
    OD
    Construction
    Pipe
    Schedule
    Finished
    Material
    Each
    35"Seamless80Steel
    		4981T2810000000

    High-Pressure Stainless Steel Threaded Pipe Flanges

    Forged for high strength, these heavy duty flanges handle high-pressure applications. Also known as ANSI flanges, they create an access point in your line. To install, bolt two flat-surface or two raised-surface flanges of the same size together with a gasket (not included). Flanges are made of stainless steel, so they have excellent corrosion resistance.
    Forged Flanges
    Image of Product. Front. Front orientation. Pipe and Fittings. High-Pressure Stainless Steel Threaded Pipe Flanges, Forged Flanges, Female, Flanged Fitting Connection, Threaded Fitting Connection, Raised Surface.
    Image of Product. Raised Surface on Back. Back orientation. Pipe and Fittings. High-Pressure Stainless Steel Threaded Pipe Flanges, Forged Flanges, Female, Flanged Fitting Connection, Threaded 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.
    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.
    Pipe
    Size
    Dash
    Size
    Bolt
    Hole
    304/304L
    Stainless Steel
    316/316L
    Stainless Steel
    (A)
    (B)
    (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
    Each
    NPT Female
    334848Raised8 1/4"3/4"0.88"86 5/8"300
    		600 psi @ 72° F300 psi @ 300° F7977K1800000007469T380000000
    334848Raised8 1/4"3/4"0.88"86 5/8"600
    		1,200 psi @ 72° F840 psi @ 400° F1441N330000001501N28000000
     

    High-Pressure Iron and Steel Threaded Pipe Flanges

    Create access points in high-pressure systems. Also known as Pressure Class 300 or Pressure Class 600 flanges, they’re stronger than low-pressure flanges. To install, bolt two same-size flanges together with a gasket (not included). Made of steel, they’re best for noncorrosive environments.
    Flanges
    Image of Product. Front. Front orientation. Pipe and Fittings. High-Pressure Iron and Steel Threaded Pipe Flanges, Flanges, Female, Flanged Fitting Connection, Threaded Fitting Connection, Raised Surface.
    Image of Product. Raised Surface on Back. Back orientation. Pipe and Fittings. High-Pressure Iron and Steel Threaded Pipe Flanges, Flanges, Female, Flanged Fitting Connection, Threaded 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
    NPT Female
    33Raised8 1/4"3/4"7/8"86 5/8"300
    		Steel
    		600 psi @ 72° F300 psi @ 300° F6806K127000000
    33Raised8 1/4"7/8"0.88"86.62"600
    		Steel
    		1,400 psi @ 72° F1,300 psi @ 300° F6806K425000000
     

    Flange Unions

    Measure, throttle, and regulate the flow of liquids and gases in your line by adding an orifice plate to these unions. They consist of two flange halves, plus all of the components needed to connect them together. Tighten the jack bolts to separate the flange halves to inspect or replace the orifice plate.
    To throttle flow, mount an orifice plate between the two flanges. The orifice plate restricts the flow in order to regulate it.
    To measure flow, build the same assembly, except you’ll also connect a differential pressure gauge or transmitter to both flange halves using the threaded ports. Your gauge or transmitter will measure the difference between the pressure before and after the orifice plate. The pressure difference is proportional to flow rate, so you can use that measurement to calculate your line’s flow rate.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Butt Weld × Flanged
    Image of Product. Assembled. Front orientation. Orifice Valves. Flange Unions, Butt-Weld Fitting Connection.
    Image of Product. Exploded. Front orientation. Exploded view. Contains Annotated. Orifice Valves. Flange Unions, Butt-Weld Fitting Connection.

    Assembled

    Exploded

    Butt-weld flanges are also known as weld-neck flanges; the flange neck has a beveled end that, when flush to pipe, creates a trough for a strong weld.
    For 316/316L Stainless Steel Fittings—316/316L stainless steel flanges have excellent corrosion resistance.
    ASME B16.36—Flanges that meet ASME B16.36 adhere to specifications and testing requirements for temperature and pressure ratings, dimensions, materials, and tolerances.
    Bolt
    Hole
    Port
    For Carbon
    Steel Fittings
    For 316/316L
    Stainless Steel Fittings
    Pipe
    Size
    Construction
    Flange
    OD
    For Bolt
    Dia.
    Dia.
    No.
    of
    Bolt Circle
    Dia.
    Pipe
    Size
    No.
    of
    Includes
    Specs. Met
    For Use With
    Temp.
    Pressure
    Class
    For Pipe
    Material
    Each
    For Pipe Material
    Each
    3Seamless8 1/4"3/4"13/16"86 9/16"1/22Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    		Carbon Steel5291N150000000316/316L Stainless Steel
    		5291N280000000
    Slip-On Weld × Flanged
    Image of Product. Assembled. Front orientation. Orifice Valves. Flange Unions, Slip-on-Weld Fitting Connection.
    Image of Product. Exploded. Front orientation. Exploded view. Contains Annotated. Orifice Valves. Flange Unions, Slip-on-Weld Fitting Connection.

    Assembled

    Exploded

    Slip-on weld flanges have no internal stop; slide a pipe through the flange and weld on both sides.
    For 316/316L Stainless Steel Fittings—316/316L stainless steel flanges have excellent corrosion resistance.
    ASME B16.36—Flanges that meet ASME B16.36 adhere to specifications and testing requirements for temperature and pressure ratings, dimensions, materials, and tolerances.
    Bolt
    Hole
    Port
    For Carbon
    Steel Fittings
    For 316/316L
    Stainless Steel Fittings
    Pipe
    Size
    Flange
    OD
    For Bolt
    Dia.
    Dia.
    No.
    of
    Bolt Circle
    Dia.
    Pipe
    Size
    No.
    of
    Includes
    Specs. Met
    For Use With
    Temp.
    Pressure
    Class
    For Pipe
    Material
    Each
    For Pipe Material
    Each
    38 1/4"3/4"13/16"86 9/16"1/22Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    		Carbon Steel5291N220000000316/316L Stainless Steel
    		5291N35000000000

    High-Pressure Galvanized Iron and Steel Threaded Pipe Flanges

    Create an access point in high-pressure lines. Also known as Pressure Class 300 flanges, bolt two of the same size together with a gasket (not included). The thick galvanized finish protects them from rust in wet and outdoor environments.
    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. High-Pressure Galvanized Iron and Steel Threaded Pipe Flanges, Flanges, Female, Flanged Fitting Connection, Threaded Fitting Connection, Raised Surface.
    Image of Product. Raised Surface on Back. Back orientation. Pipe and Fittings. High-Pressure Galvanized Iron and Steel Threaded Pipe Flanges, Flanges, Female, Flanged Fitting Connection, Threaded 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
    NPT Female
    33Raised8 1/4"7/8"0.88"86 5/8"300
    		Galvanized Steel600 psi @ 72° FNot Rated1733N170000000
     
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