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    138 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

    Use these heavy duty forged flanges for high-pressure applications. Bolt two flat-surface flanges or two raised-surface flanges of same size together with a gasket (sold separately) to create an access point in a pipe line.
    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
    1/2
    1/2
    0808Raised3 3/4"1/2"0.625"42 5/8"300
    600 psi @ 72° F415 psi @ 360° F4448T2860000004452T296000000
    3/4
    3/4
    1212Raised4 5/8"5/8"0.75"43 1/4"300
    600 psi @ 72° F415 psi @ 360° F4448T287000004452T29700000
    1
    1
    1616Raised4 7/8"5/8"0.75"43 1/2"300
    600 psi @ 72° F415 psi @ 360° F4448T288000004452T29800000
    1 1/4
    1 1/4
    2020Raised5 1/4"5/8"0.75"43 7/8"300
    600 psi @ 72° F415 psi @ 360° F4448T2890000004452T299000000
    1 1/2
    1 1/2
    2424Raised6 1/8"3/4"0.875"44 1/2"300
    600 psi @ 72° F415 psi @ 360° F4448T2910000004452T311000000
    2
    2
    3232Raised6 1/2"5/8"0.75"85"300
    600 psi @ 72° F415 psi @ 360° F4448T2920000004452T312000000
    2 1/2
    2 1/2
    4040Raised7 1/2"3/4"0.875"85 7/8"300
    600 psi @ 72° F415 psi @ 360° F4448T2930000004452T313000000
    3
    3
    4848Raised8 1/4"3/4"0.875"86 5/8"300
    600 psi @ 72° F415 psi @ 360° F4448T2940000004452T314000000
    4
    4
    6464Raised10"3/4"0.875"87 7/8"300
    600 psi @ 72° F415 psi @ 360° F4448T2950000004452T315000000
    6
    6
    9696Raised12 1/2"3/4"0.875"1210 5/8"300
    600 psi @ 72° F415 psi @ 360° F4448T2960000004452T316000000
     
    Slip-On Weld Female
    1/2
    1/2
    0808Raised3 3/4"1/2"0.625"42 5/8"300
    600 psi @ 72° F300 psi @ 360° F4448T251000004452T26100000
    3/4
    3/4
    1212Raised4 5/8"5/8"0.75"43 1/4"300
    600 psi @ 72° F300 psi @ 360° F4448T252000004452T26200000
    1
    1
    1616Raised4 7/8"5/8"0.75"43 1/2"300
    600 psi @ 72° F300 psi @ 360° F4448T253000004452T26300000
    1 1/4
    1 1/4
    2020Raised5 1/4"5/8"0.75"43 7/8"300
    600 psi @ 72° F300 psi @ 360° F4448T254000004452T264000000
    1 1/2
    1 1/2
    2424Raised6 1/8"3/4"0.875"44 1/2"300
    600 psi @ 72° F300 psi @ 360° F4448T2550000004452T265000000
    2
    2
    3232Raised6 1/2"5/8"0.75"85"300
    600 psi @ 72° F300 psi @ 360° F4448T2560000004452T266000000
    2 1/2
    2 1/2
    4040Raised7 1/2"3/4"0.875"85 7/8"300
    600 psi @ 72° F300 psi @ 360° F4448T2570000004452T267000000
    3
    3
    4848Raised8 1/4"3/4"0.875"86 5/8"300
    600 psi @ 72° F300 psi @ 360° F4448T2580000004452T268000000
    4
    4
    6464Raised10"3/4"0.875"87 7/8"300
    600 psi @ 72° F300 psi @ 360° F4448T2590000004452T269000000
    6
    6
    9696Raised12 1/2"3/4"0.875"1210 5/8"300
    600 psi @ 72° F300 psi @ 360° F4448T2610000004452T271000000
    8
    8
    Raised15"7/8"1"1213"300
    600 psi @ 72° F300 psi @ 360° F4448T43000000———0
     
    Socket-Connect Female
    1/2
    1/2
    0808Raised3 3/4"1/2"0.625"42 5/8"300
    600 psi @ 72° F300 psi @ 360° F4448T264000004452T27400000
    3/4
    3/4
    1212Raised4 5/8"5/8"0.75"43 1/4"300
    600 psi @ 72° F300 psi @ 360° F4448T265000004452T27500000
    1
    1
    1616Raised4 7/8"5/8"0.75"43 1/2"300
    600 psi @ 72° F300 psi @ 360° F4448T266000004452T27600000
    1 1/4
    1 1/4
    2020Raised5 1/4"5/8"0.75"43 7/8"300
    600 psi @ 72° F300 psi @ 360° F4448T2670000004452T277000000
    1 1/2
    1 1/2
    2424Raised6 1/8"3/4"0.875"44 1/2"300
    600 psi @ 72° F300 psi @ 360° F4448T268000004452T278000000
    2
    2
    3232Raised6 1/2"5/8"0.75"85"300
    600 psi @ 72° F300 psi @ 360° F4448T2690000004452T279000000
    2 1/2
    2 1/2
    4040Raised7 1/2"3/4"0.875"85 7/8"300
    600 psi @ 72° F300 psi @ 360° F4448T271000000———0
    3
    3
    4848Raised8 1/4"3/4"0.875"86 5/8"300
    600 psi @ 72° F300 psi @ 360° F4448T2720000004452T282000000
    4
    4
    6464Raised10"3/4"0.875"87 7/8"300
    600 psi @ 72° F300 psi @ 360° F4448T2730000004452T283000000
    6
    6
    9696Raised12 1/2"3/4"0.875"1210 5/8"300
    600 psi @ 72° F300 psi @ 360° F4448T274000000———0
     
    Stub End
    3/4
    3/4
    1212Flat4 5/8"5/8"0.75"43 1/4"300
    600 psi @ 72° F300 psi @ 360° F4448T29800000———0
    1
    1
    1616Flat4 7/8"5/8"0.75"43 1/2"300
    600 psi @ 72° F300 psi @ 360° F4448T299000004452T31900000
    1 1/2
    1 1/2
    2424Flat6 1/8"3/4"0.875"44 1/2"300
    600 psi @ 72° F300 psi @ 360° F4448T3120000004452T322000000
    2
    2
    3232Flat6 1/2"5/8"0.75"85"300
    600 psi @ 72° F300 psi @ 360° F4448T3130000004452T323000000
    2 1/2
    2 1/2
    4040Flat7 1/2"3/4"0.875"85 7/8"300
    600 psi @ 72° F300 psi @ 360° F4448T3140000004452T324000000
    3
    3
    4848Flat8 1/4"3/4"0.875"86 5/8"300
    600 psi @ 72° F300 psi @ 360° F4448T3150000004452T325000000
    4
    4
    6464Flat10"3/4"0.875"87 7/8"300
    600 psi @ 72° F300 psi @ 360° F4448T262000000———0
    6
    6
    9696Flat12 1/2"3/4"0.875"1210 5/8"300
    600 psi @ 72° F300 psi @ 360° F4448T263000000———0
     
    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
    1/2
    08Raised3 3/4"1/2"0.625"42 5/8"300
    600 psi @ 72° F300 psi @ 360° F4448T2750000004452T285000000
    3/4
    12Raised4 5/8"5/8"0.75"43 1/4"300
    600 psi @ 72° F300 psi @ 360° F4448T276000004452T28600000
    1
    16Raised4 7/8"5/8"0.75"43 1/2"300
    600 psi @ 72° F300 psi @ 360° F4448T277000004452T28700000
    1 1/4
    20Raised5 1/4"5/8"0.75"43 7/8"300
    600 psi @ 72° F300 psi @ 360° F4448T278000004452T288000000
    1 1/2
    24Raised6 1/8"3/4"0.875"44 1/2"300
    600 psi @ 72° F300 psi @ 360° F4448T2790000004452T289000000
    2
    32Raised6 1/2"5/8"0.75"85"300
    600 psi @ 72° F300 psi @ 360° F4448T2810000004452T291000000
    2 1/2
    40Raised7 1/2"3/4"0.875"85 7/8"300
    600 psi @ 72° F300 psi @ 360° F4448T2820000004452T292000000
    3
    48Raised8 1/4"3/4"0.875"86 5/8"300
    600 psi @ 72° F300 psi @ 360° F4448T2830000004452T293000000
    4
    64Raised10"3/4"0.875"87 7/8"300
    600 psi @ 72° F300 psi @ 360° F4448T2840000004452T294000000
    6
    96Raised12 1/2"3/4"0.875"1210 5/8"300
    600 psi @ 72° F300 psi @ 360° F4448T2850000004452T295000000
    8
    Raised15"7/8"1"1213"300
    600 psi @ 72° F300 psi @ 360° F4448T480000004452T116000000
    10
    Raised17 1/2"1"1.12"1615 1/4"300
    600 psi @ 72° F300 psi @ 360° F4448T49000000———0
     
    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
    3/4
    0.113"1 11/16"Welded40
    45605K652000000———0
    1
    0.133"2"Welded40
    45605K6530000045555K653000000
    1 1/2
    0.145"2 7/8"Welded40
    45605K6550000045555K65500000
    2
    0.154"3 5/8"Welded40
    45605K6560000045555K65600000
    2 1/2
    0.203"4 1/8"Welded40
    45605K6570000045555K65700000
    3
    0.216"5"Welded40
    45605K6610000045555K66100000
    4
    0.237"6 3/16"Welded40
    45605K66300000———0
    6
    0.28"8 1/2"Welded40
    45605K665000000———0

    High-Pressure Stainless Steel Threaded Pipe Flanges

    Forged for high strength, these heavy duty flanges can handle high-pressure applications. They are also known as ANSI flanges. Bolt two same-size flanges 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. High-Pressure Stainless Steel Threaded Pipe Flanges, Forged Flanges, Flanged Fitting Connection, Female, 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, Flanged Fitting Connection, Female, 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
    1/2
    1/2
    0808Raised3 3/4"1/2"0.62"42 5/8"300
    600 psi @ 72° F300 psi @ 300° F7977K110000007469T31000000
    3/4
    3/4
    1212Raised4 5/8"5/8"0.75"43 1/4"300
    600 psi @ 72° F300 psi @ 300° F7977K12000007469T3200000
    1
    1
    1616Raised4 7/8"5/8"0.75"43 1/2"300
    600 psi @ 72° F300 psi @ 300° F7977K13000007469T3300000
    1 1/4
    1 1/4
    2020Raised5 1/4"5/8"0.75"43 7/8"300
    600 psi @ 72° F300 psi @ 300° F7977K14000007469T34000000
    1 1/2
    1 1/2
    2424Raised6 1/8"3/4"0.88"44 1/2"300
    600 psi @ 72° F300 psi @ 300° F7977K15000007469T35000000
    2
    2
    3232Raised6 1/2"5/8"0.75"85"300
    600 psi @ 72° F300 psi @ 300° F7977K16000007469T36000000
    2 1/2
    2 1/2
    4040Raised7 1/2"3/4"0.88"85 7/8"300
    600 psi @ 72° F300 psi @ 300° F7977K170000007469T37000000
    3
    3
    4848Raised8 1/4"3/4"0.88"86 5/8"300
    600 psi @ 72° F300 psi @ 300° F7977K180000007469T38000000
    4
    4
    6464Raised10"3/4"0.875"87 7/8"300
    600 psi @ 72° F300 psi @ 300° F7977K190000007469T39000000
     

    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.
    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 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
    3/4Seamless4 5/8"5/8"11/16"43 1/4"1/2
    2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsAir, Natural Gas, Oil, WaterNot Rated300
    316/316L Stainless Steel
    5291N240000000
    1Seamless4 7/8"5/8"11/16"43 1/2"1/2
    2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    316/316L Stainless Steel
    5291N25000000
    1 1/2Seamless6 1/8"3/4"13/16"44 1/2"1/2
    2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    316/316L Stainless Steel
    5291N26000000
    2Seamless6 1/2"5/8"11/16"85"1/2
    2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    316/316L Stainless Steel
    5291N27000000
    3Seamless8 1/4"3/4"13/16"86 9/16"1/2
    2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    316/316L Stainless Steel
    5291N28000000
    4Seamless10"3/4"13/16"87 7/8"1/2
    2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    316/316L Stainless Steel
    5291N2900000000
    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.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Bolt
    Hole
    Port
    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
    3/44 5/8"5/8"11/16"43 1/4"1/2
    2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsAir, Natural Gas, Oil, WaterNot Rated300
    316/316L Stainless Steel
    5291N310000000
    14 7/8"5/8"11/16"43 1/2"1/2
    2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    316/316L Stainless Steel
    5291N32000000
    1 1/26 1/8"3/4"13/16"44 1/2"1/2
    2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    316/316L Stainless Steel
    5291N33000000
    26 1/2"5/8"11/16"85"1/2
    2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    316/316L Stainless Steel
    5291N34000000
    38 1/4"3/4"13/16"86 9/16"1/2
    2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    316/316L Stainless Steel
    5291N3500000000
    410"3/4"13/16"87 7/8"1/2
    2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    316/316L Stainless Steel
    5291N3600000000
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