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    46 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 Fittings

    Suitable for use in fire-protection applications, these fittings are cast iron, so they’re brittle enough to be opened with a sledgehammer. They’re also known as Pressure Class 125 fittings. Use in noncorrosive environments.
    Square-Drive Plugs
    Image of Product. NPT Male. Front orientation. Pipe and Fittings. FM-Approved Low-Pressure Iron and Steel Threaded Pipe Fittings, Square-Drive Plugs, Threaded Fitting Connection, Male.

    NPT Male

    Pipe
    Size
    Construction
    Pressure
    Class
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Certification
    Each
    NPT Male
    1
    		Solid125
    		Cast Iron175 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68115K105000000
    1 1/4
    		Solid125
    		Cast Iron175 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68115K10600000
    1 1/2
    		Solid125
    		Cast Iron175 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68115K10700000
    2
    		Solid125
    		Cast Iron175 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68115K10800000
    2 1/2
    		Solid125
    		Cast Iron175 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68115K10900000
    3
    		Solid125
    		Cast Iron175 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68115K11100000
    4
    		Solid125
    		Cast Iron175 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68115K112000000
     
    External-Square-Drive Plugs
    Image of Product. NPT Male. Front orientation. Pipe and Fittings. FM-Approved Low-Pressure Iron and Steel Threaded Pipe Fittings, External-Square-Drive Plugs, Threaded Fitting Connection, Male.

    NPT Male

    Pipe
    Size
    Construction
    Pressure
    Class
    Body
    Shape
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Certification
    Each
    NPT Male
    1
    		Solid125
    		SquareCast Iron175 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68115K11300000
    1 1/4
    		Solid125
    		SquareCast Iron175 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68115K1140000
    1 1/2
    		Solid125
    		SquareCast Iron175 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68115K1150000
    2
    		Solid125
    		SquareCast Iron175 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68115K11600000
    2 1/2
    		Solid125
    		SquareCast Iron175 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68115K11700000
    3
    		Solid125
    		SquareCast Iron175 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68115K11800000
    4
    		Solid125
    		SquareCast Iron175 psi @ 72° F125 psi @ 350° FFM Approved, UL Listed
    		68115K11900000
     

    Medium-Pressure Iron and Steel Threaded Pipe Fittings

    With better strength than our low-pressure iron and steel pipe fittings, these can handle medium-pressure applications. They are for use in noncorrosive environments.
    External-Square-Drive Plugs
    Image of Product. NPT Male. Front orientation. Pipe and Fittings. Medium-Pressure Iron and Steel Threaded Pipe Fittings, External-Square-Drive Plugs, Threaded Fitting Connection, Male, Square Body.

    NPT Male

    Pipe
    Size
    Construction
    Pressure
    Class
    Body
    Shape
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Certification
    Each
    NPT Male
    1/2
    		Solid300
    		SquareIron400 psi @ 72° F300 psi @ 550° FUL Listed
    		4627K33300000
    3/4
    		Solid300
    		SquareIron400 psi @ 72° F300 psi @ 550° FUL Listed
    		4627K3340000
    1
    		Solid300
    		SquareIron400 psi @ 72° F300 psi @ 550° FUL Listed
    		4627K3350000
    1 1/4
    		Solid300
    		SquareIron400 psi @ 72° F300 psi @ 550° FUL Listed
    		4627K33600000
    1 1/2
    		Solid300
    		SquareIron400 psi @ 72° F300 psi @ 550° FUL Listed
    		4627K33700000
    2
    		Solid300
    		SquareIron400 psi @ 72° F300 psi @ 550° FUL Listed
    		4627K33800000
    2 1/2
    		Solid300
    		SquareIron400 psi @ 72° F300 psi @ 550° FUL Listed
    		4627K41600000
     

    Low-Pressure Galvanized Iron and Steel Threaded Pipe Fittings

    Commonly used in low-pressure water supply and utility piping systems, these galvanized fittings won't rust in wet and outdoor environments.
    Bushing Straight Reducing Adapters
    Image of Product. Male x Female. Front orientation. Contains Annotated. Pipe and Fittings. Low-Pressure Galvanized Iron and Steel Threaded Pipe Fittings, Bushing Straight Reducing Adapters, Female, Threaded Fitting Connection, Male.
    Image of Product. Male x Female. Front orientation. Contains Annotated. Pipe and Fittings. Low-Pressure Galvanized Iron and Steel Threaded Pipe Fittings, Bushing Straight Reducing Adapters, Female, Threaded Fitting Connection, Male, Hex Body.

    Male x Female

    Male x Female

    Pipe
    Size
    (A)
    (B)
    Pressure
    Class
    Body
    Shape
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    NPT Male × NPT Female
    1 1/4
    		3/8
    		125
    		HexGalvanized Iron125 psi @ 72° F125 psi @ 350° F4638K06100000
    1 1/2
    		3/8
    		125
    		HexGalvanized Iron125 psi @ 72° F125 psi @ 350° F4638K06300000
    1 1/2
    		1/2
    		125
    		HexGalvanized Iron125 psi @ 72° F125 psi @ 350° F4638K0620000
    2
    		1/2
    		125
    		HexGalvanized Iron125 psi @ 72° F125 psi @ 350° F4638K06400000
    2
    		3/4
    		125
    		HexGalvanized Iron125 psi @ 72° F125 psi @ 350° F4638K06500000
    2 1/2
    		1 1/2
    		125
    		HexGalvanized Iron125 psi @ 72° F125 psi @ 350° F4638K05800000
    3
    		2
    		125
    		HexGalvanized Iron125 psi @ 72° F125 psi @ 350° F4638K05900000
    3
    		2 1/2
    		125
    		HexGalvanized Iron125 psi @ 72° F125 psi @ 350° F4638K0600000
     
    External-Square-Drive Plugs
    Image of Product. Front orientation. Pipe and Fittings. Low-Pressure Galvanized Iron and Steel Threaded Pipe Fittings, External-Square-Drive Plugs, Threaded Fitting Connection, Male.

    Male, Threaded

    Fitting

    Connection

    Pipe
    Size
    Construction
    Pressure
    Class
    Body
    Shape
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Certification
    Each
    NPT Male
    2 1/2
    		Hollow125
    		SquareGalvanized Iron125 psi @ 72° F125 psi @ 350° FUL Listed
    		4638K934000000
    3
    		Hollow125
    		SquareGalvanized Iron125 psi @ 72° F125 psi @ 350° FUL Listed
    		4638K93500000
    3 1/2
    		Hollow125
    		SquareGalvanized Iron125 psi @ 72° F125 psi @ 350° FUL Listed
    		4638K93600000
    4
    		Hollow125
    		SquareGalvanized Iron125 psi @ 72° F125 psi @ 350° FUL Listed
    		4638K939000000
     
    180° Bend Connectors
    Image of Product. Front orientation. Pipe Traps. Low-Pressure Galvanized 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 1/2
    		Galvanized Iron150 psi @ 72° F150 psi @ 350° FUL Listed
    		180° Bend4638K5560000000
    2
    		Galvanized Iron150 psi @ 72° F150 psi @ 350° FUL Listed
    		180° Bend4638K557000000
     
    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.
    Max. Steam
    Pressure @ Temp.
    Each
    NPSL Female
    1 1/4
    		Galvanized IronNot RatedNot Rated4638K617000000
    1 1/2
    		Galvanized IronNot RatedNot Rated4638K61800000
    2
    		Galvanized IronNot RatedNot Rated4638K61900000
     

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

    FM approved for fire protection lines, these cap flanges create access points that open with a sledgehammer. They’re made of brittle cast iron, so you can break the seal quickly to get into water mains and sprinkler systems. Bolt two flanges of the same size together with a gasket (not included). Also known as blind flanges.
    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
     
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