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    75 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

    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
     

    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, Flanged Fitting Connection, Threaded Fitting Connection, Female, Flat Surface.
    Image of Product. Flat Surface on Back. Back orientation. Pipe and Fittings. Low-Pressure Brass and Bronze Threaded Pipe Flanges, Flanges, Flanged Fitting Connection, Threaded Fitting Connection, Female, Flat Surface.

    Front

    Flat Surface

    on Back

    NSF/ANSI 61—To adhere to safety standards for drinking water systems, use pipe that meets NSF/ANSI 61.
    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.
    Food Industry
    Std.
    Each
    NPT Female
    1/2
    		1/2
    		Flat3 1/2"1/2"5/8"42 3/8"150
    		Brass225 psi @ 72° FNSF/ANSI 61
    		4429K551000000
    3/4
    		3/4
    		Flat3 7/8"1/2"5/8"42 3/4"150
    		Brass225 psi @ 72° FNSF/ANSI 61
    		4429K55200000
    1
    		1
    		Flat4 1/4"1/2"5/8"43 1/8"150
    		Brass225 psi @ 72° FNSF/ANSI 61
    		4429K55300000
    1 1/4
    		1 1/4
    		Flat4 5/8"1/2"5/8"43 1/2"150
    		Brass225 psi @ 72° FNSF/ANSI 61
    		4429K55400000
    1 1/2
    		1 1/2
    		Flat5"1/2"5/8"43 7/8"150
    		Brass225 psi @ 72° FNSF/ANSI 61
    		4429K555000000
    2
    		2
    		Flat6"5/8"3/4"44 3/4"150
    		Brass225 psi @ 72° FNSF/ANSI 61
    		4429K556000000
    2 1/2
    		2 1/2
    		Flat7"5/8"3/4"45 1/2"150
    		Brass225 psi @ 72° FNSF/ANSI 61
    		4429K557000000
    3
    		3
    		Flat7 1/2"5/8"3/4"46"150
    		Brass225 psi @ 72° FNSF/ANSI 61
    		4429K558000000
    4
    		4
    		Flat9"5/8"3/4"87 1/2"150
    		Brass225 psi @ 72° FNSF/ANSI 61
    		4429K559000000
     

    Low-Pressure Iron and Steel Threaded Pipe Fittings

    Use these fittings for low-pressure applications in noncorrosive environments.
    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, Female, Butt-Weld Fitting Connection, 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
    1/8
    		15/16"1 5/16"FlatCarbon SteelNot Rated12555K7900000
    1/8
    		15/16"1 1/2"FlatCarbon SteelNot Rated12555K690000
    1/4
    		15/16"1 5/16"FlatCarbon SteelNot Rated12555K810000
    1/4
    		15/16"1 1/2"FlatCarbon SteelNot Rated12555K710000
    3/8
    		15/16"1 5/16"FlatCarbon SteelNot Rated12555K820000
    3/8
    		15/16"1 1/2"FlatCarbon SteelNot Rated12555K720000
    1/2
    		1 1/8"1 5/8"FlatCarbon SteelNot Rated12555K830000
    1/2
    		1 1/8"1 3/4"FlatCarbon SteelNot Rated12555K730000
    3/4
    		1 5/16"1 15/16"FlatCarbon SteelNot Rated12555K840000
    3/4
    		1 3/8"2 1/8"FlatCarbon SteelNot Rated12555K740000
    1
    		1 5/8"2 3/8"FlatCarbon SteelNot Rated12555K750000
    1
    		1 11/16"2 1/4"FlatCarbon SteelNot Rated12555K850000
    1 1/4
    		2"2 9/16"FlatCarbon SteelNot Rated12555K8600000
    1 1/4
    		2"2 11/16"FlatCarbon SteelNot Rated12555K760000
    1 1/2
    		2 1/4"2 13/16"FlatCarbon SteelNot Rated12555K870000
    1 1/2
    		2 1/4"3"FlatCarbon SteelNot Rated12555K770000
    2
    		2 5/8"3 3/8"FlatCarbon SteelNot Rated12555K880000
    2
    		2 5/8"3 1/2"FlatCarbon SteelNot Rated12555K7800000
    2 1/2
    		3 1/8"4 1/16"FlatCarbon SteelNot Rated12555K8900000
    3
    		3 5/8"4 5/8"FlatCarbon SteelNot Rated12555K9100000
    4
    		4 11/16"5 13/16"FlatCarbon SteelNot Rated12555K9200000
     
    180° Bend Connectors
    Image of Product. Front orientation. Pipe Traps. Low-Pressure Iron and Steel Threaded Pipe Fittings.
    180° bend connectors are also known as U-bends.
    Pipe
    Size
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Certification
    Shape
    Each
    NPT Female
    1/2
    		Iron150 psi @ 72° F150 psi @ 350° FUL Listed
    		180° Bend44605K563000000
    3/4
    		Iron150 psi @ 72° F150 psi @ 350° FUL Listed
    		180° Bend44605K56400000
    1
    		Iron150 psi @ 72° F150 psi @ 350° F—180° Bend44605K56500000
    1 1/4
    		Iron150 psi @ 72° F150 psi @ 350° FUL Listed
    		180° Bend44605K56600000
    1 1/2
    		Iron150 psi @ 72° F150 psi @ 350° FUL Listed
    		180° Bend44605K567000000
    2
    		Iron150 psi @ 72° F150 psi @ 350° FUL Listed
    		180° Bend44605K568000000
     

    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
     

    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, Female, Butt-Weld Fitting Connection, Threaded Fitting Connection, 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
    3/8
    		15/16"1 1/2"FlatNot Rated1145K5200000
    1/2
    		1 1/8"1 3/4"FlatNot Rated1145K5300000
    3/4
    		1 3/8"2 1/8"FlatNot Rated1145K5400000
    1
    		1 11/16"2 3/8"FlatNot Rated1145K5500000
    1 1/4
    		2"2 11/16"FlatNot Rated1145K5600000
    1 1/2
    		2 1/4"3"FlatNot Rated1145K5700000
    2
    		2 5/8"3 1/2"FlatNot Rated1145K5800000
    2 1/2
    		3 3/16"4 1/16"FlatNot Rated1145K59000000
    3
    		3 11/16"4 5/8"FlatNot Rated1145K61000000
    4
    		4 7/8"5 3/4"FlatNot Rated1145K62000000
     
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