McMaster-Carr logo
    Forward
    Enter e-mail addresses in the fields below
    Message
    Cancel
    Print
    How can we improve?
    Comments
    E-mail address (if you would like a response)
    28 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.

    Fitting Type

    Fitting Type

    Threading

    FM-Approved Low-Pressure Iron and Steel Threaded Pipe Flanges

    Suitable for use in fire-protection applications, these flanges are brittle and can be quickly opened with the strike of a sledge hammer. Bolt two flanges of the same size together with a gasket (sold separately) to create an access point within a line. Use in noncorrosive environments.
    Cast Flanges
    Image of Product. Front. Front orientation. Pipe and Fittings. FM-Approved Low-Pressure Iron and Steel Threaded Pipe Flanges, Cast Flanges, Flanged Fitting Connection, Threaded Fitting Connection, Female, Flat Surface.

    Front

    Cast flanges are also called MSS flanges.
    Pipe
    Size
    Bolt
    Hole
    (A)
    (B)
    Flanged Connection
    Surface (B)
    Flange
    OD
    For Bolt
    Dia.
    Dia.
    No.
    Of
    Bolt Circle
    Dia.
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Certification
    Each
    NPT Female
    3/4
    		3/4
    		Flat3 7/8"1/2"5/8"42 3/4"Cast Iron125 psi @ 72° F125 psi @ 350° FFM Approved
    		68185K111000000
    1
    		1
    		Flat4 1/4"1/2"5/8"43 1/8"Cast Iron125 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68185K11200000
    1 1/4
    		1 1/4
    		Flat4 5/8"1/2"5/8"43 1/2"Cast Iron125 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68185K11300000
    1 1/2
    		1 1/2
    		Flat5"1/2"5/8"43 7/8"Cast Iron125 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68185K11400000
    2
    		2
    		Flat6"5/8"3/4"44 3/4"Cast Iron125 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68185K11500000
    2 1/2
    		2 1/2
    		Flat7"5/8"3/4"45 1/2"Cast Iron125 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68185K11600000
    3
    		3
    		Flat7 1/2"5/8"3/4"46"Cast Iron125 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68185K11700000
    4
    		4
    		Flat9"5/8"3/4"87 1/2"Cast Iron125 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68185K118000000
    5
    		5
    		Flat10"3/4"7/8"88 1/2"Cast Iron125 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68185K131000000
    6
    		6
    		Flat11"3/4"7/8"89 1/2"Cast Iron125 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68185K132000000
    8
    		8
    		Flat13 1/2"3/4"7/8"811 3/4"Cast Iron125 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68185K133000000
     
    Cast Reducing Flanges
    Image of ProductInUse. Reducing Flange. Side1 orientation. Contains Annotated. Pipe and Fittings. FM-Approved Low-Pressure Iron and Steel Threaded Pipe Flanges, Cast Reducing Flanges, Flanged Fitting Connection, Threaded Fitting Connection, Female, Flat Surface.
    Image of Product. Front. Front orientation. Pipe and Fittings. FM-Approved Low-Pressure Iron and Steel Threaded Pipe Flanges, Cast Reducing Flanges, Flanged Fitting Connection, Threaded Fitting Connection, Female, Flat Surface.

    Reducing

    Flange

    Front

    Cast flanges are also called MSS 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.
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Certification
    Each
    NPT Female
    2
    		2 1/2
    		Flat7"5/8"3/4"45 1/2"Cast Iron175 psi @ 72° F125 psi @ 350° FFM Approved
    		68185K1010000000
    2
    		3
    		Flat7 1/2"5/8"3/4"46"Cast Iron175 psi @ 72° F125 psi @ 350° FFM Approved
    		68185K102000000
    2
    		4
    		Flat9"5/8"3/4"87 1/2"Cast Iron175 psi @ 72° F125 psi @ 350° FFM Approved
    		68185K103000000
    3
    		4
    		Flat9"5/8"3/4"87 1/2"Cast Iron175 psi @ 72° F125 psi @ 350° FFM Approved
    		68185K104000000
    4
    		6
    		Flat11"3/4"7/8"89 1/2"Cast Iron175 psi @ 72° F125 psi @ 350° FFM Approved
    		68185K105000000
     

    FM-Approved Low-Pressure Iron and Steel Unthreaded Pipe Flanges

    FM-approved for fire protection applications, these flanges are cast iron, so they're brittle and can be quickly opened by hitting them with a sledge hammer. Bolt them together with a gasket (not included) to create an access point within a low-pressure pipe line. All are cap flanges, which are also known as blind flanges. Use them in noncorrosive environments.
    Cast Blind Flanges
    Image of Product. Front. Front orientation. Pipe and Fittings. FM-Approved Low-Pressure Iron and Steel Unthreaded Pipe Flanges.
    Image of Product. Back. Back orientation. Pipe and Fittings. FM-Approved Low-Pressure Iron and Steel Unthreaded Pipe Flanges.

    Front

    Back

    Cast flanges are also called MSS flanges.
    Bolt
    Hole
    Pipe
    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.
    Certification
    Each
    Flanged
    1
    		Flat4 1/4"1/2"5/8"43 1/8"125
    		Cast Iron200 psi @ 72° F165 psi @ 300° FFM Approved
    		4824N11000000
    1 1/2
    		Flat5"1/2"5/8"43 7/8"125
    		Cast Iron200 psi @ 72° F165 psi @ 300° FFM Approved
    		4824N1200000
    2
    		Flat6"5/8"3/4"44 3/4"125
    		Cast Iron200 psi @ 72° F165 psi @ 300° FFM Approved
    		4824N1300000
    2 1/2
    		Flat7"5/8"3/4"45 1/2"125
    		Cast Iron200 psi @ 72° F165 psi @ 300° FFM Approved
    		4824N1400000
    3
    		Flat7 1/2"5/8"3/4"46"125
    		Cast Iron200 psi @ 72° F165 psi @ 300° FFM Approved
    		4824N1500000
    3 1/2
    		Flat8 1/2"5/8"3/4"87"125
    		Cast Iron200 psi @ 72° F165 psi @ 300° FFM Approved
    		4824N16000000
    4
    		Flat9"5/8"3/4"87 1/2"125
    		Cast Iron200 psi @ 72° F165 psi @ 300° FFM Approved
    		4824N17000000
    6
    		Flat11"3/4"7/8"89 1/2"125
    		Cast Iron200 psi @ 72° F165 psi @ 300° FFM Approved
    		4824N18000000
     

    FM-Approved Low-Pressure Iron and Steel Flanged-End Pipe Fittings

    FM approved, these fittings are suitable for use in fire-protection systems. All have flat-surface flanged ends that only mate to another same-size flat-surface flange, pump, or valve with a gasket (sold separately) to create an access point in a pipeline. Use them in noncorrosive areas.
    Straight Reducers
    Image of Product. Front orientation. Contains Annotated. Pipe and Fittings. FM-Approved Low-Pressure Iron and Steel Flanged-End Pipe Fittings, Straight Reducers, Flanged × Flanged.

    Flanged × Flanged

    Pipe
    Size
    Flange
    OD
    (A)
    (B)
    (A)
    (B)
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Mil. Spec.
    Certification
    Each
    Flanged × Flanged
    2 1/2
    		2
    		7"6"Iron150 psi @ 72° F125 psi @ 350° FFed. Spec. WW-F-406FM Approved, UL Listed
    		1117T190000000
    3
    		2
    		7 1/2"6"Iron150 psi @ 72° F125 psi @ 350° FFed. Spec. WW-F-406FM Approved, UL Listed
    		1117T22000000
    3
    		2 1/2
    		7 1/2"7"Iron150 psi @ 72° F125 psi @ 350° FFed. Spec. WW-F-406FM Approved, UL Listed
    		1117T21000000
    4
    		3
    		9"7 1/2"Iron150 psi @ 72° F125 psi @ 350° FFed. Spec. WW-F-406FM Approved, UL Listed
    		1117T23000000
     
    back to top