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    22 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.

    Standard-Wall Butt-Weld Steel Unthreaded Pipe Stub Ends

    Image of System. Straight Pipe Stub End with Pipe Flange. Front orientation. Pipe Stub Ends. Standard-Wall Butt-Weld Steel Unthreaded Pipe Stub Ends.
    Image of Product. Straight Adapter. Front orientation. Pipe Stub Ends. Standard-Wall Butt-Weld Steel Unthreaded Pipe Stub Ends.

    Straight Pipe Stub

    End with Pipe Flange

    Straight Adapter

    Butt-weld pipe stub ends allow for a smooth connection that provides maximum flow. They have beveled ends that, when flush to pipe, create a trough for a strong, permanent weld. Pipe stub ends are also known as Schedule 40. They are for use in noncorrosive environments.
    Pipe stub ends 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 Stub Ends
    Flanges
    For Pipe
    For
    Flange
    Pipe
    Size
    Wall
    Thk.
    Flange
    OD
    Construction
    For Use With
    Specs. Met
    Schedule
    Material
    Class
    Material
    Each
    Each
    Straight Pipe Stub Ends, Butt Weld × Flanged
     
    Steel
    1/2
    		0.109"1 3/8"SeamlessAir, Natural Gas, Oil, Steam, WaterASME B16.9, ASTM A23440
    		Steel150
    		Steel43425K11500000068095K422000000
    3/4
    		0.113"1 11/16"SeamlessAir, Natural Gas, Oil, Steam, WaterASME B16.9, ASTM A23440
    		Steel150
    		Steel43425K1250000068095K38500000
    1
    		0.133"2"SeamlessAir, Natural Gas, Oil, Steam, WaterASME B16.9, ASTM A23440
    		Steel150
    		Steel43425K1350000068095K38600000
    1 1/4
    		0.14"2 1/2"SeamlessAir, Natural Gas, Oil, Steam, WaterASME B16.9, ASTM A23440
    		Steel150
    		Steel43425K14500000068095K38700000
    1 1/2
    		0.145"2 7/8"SeamlessAir, Natural Gas, Oil, Steam, WaterASME B16.9, ASTM A23440
    		Steel150
    		Steel43425K15500000068095K38800000
    2
    		0.154"3 5/8"SeamlessAir, Natural Gas, Oil, Steam, WaterASME B16.9, ASTM A23440
    		Steel150
    		Steel43425K16500000068095K38900000
    2 1/2
    		0.203"4 1/8"SeamlessAir, Natural Gas, Oil, Steam, WaterASME B16.9, ASTM A23440
    		Steel150
    		Steel43425K17500000068095K39100000
    3
    		0.216"5"SeamlessAir, Natural Gas, Oil, Steam, WaterASME B16.9, ASTM A23440
    		Steel150
    		Steel43425K18500000068095K39200000
    4
    		0.237"6 3/16"SeamlessAir, Natural Gas, Oil, Steam, WaterASME B16.9, ASTM A23440
    		Steel150
    		Steel43425K21500000068095K39300000
    6
    		0.28"8 1/2"SeamlessAir, Natural Gas, Oil, Steam, WaterASME B16.9, ASTM A23440
    		Steel150
    		Steel43425K23500000068095K39400000
    8
    		0.322"10 5/8"SeamlessAir, Natural Gas, Oil, Steam, WaterASME B16.9, ASTM A23440
    		Steel150
    		Steel43425K24500000068095K421000000
     

    Low-Pressure Iron and Steel Unthreaded Pipe Flanges

    Bolt two flat-surface flanges or two raised-surface flanges of the same size together with a gasket (sold separately) to create an access point in a pipe line. Flanges are for use with low-pressure applications in noncorrosive environments.
    Flanges
    Image of System. Stub-End Flange with Straight Adapter: Front. Front orientation. Contains Annotated. Pipe and Fittings. Low-Pressure Iron and Steel Unthreaded Pipe Flanges, Flanges, Stub-End Female, Flat Surface.
    Image of Product. Stub End: Flat Surface on Back. Back orientation. Pipe and Fittings. Low-Pressure Iron and Steel Unthreaded Pipe Flanges, Flanges, Stub-End Female, Flat Surface.

    Stub-End Flange with Straight

    Adapter: Front

    Stub End:

    Flat

    Surface

    on Back

    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
    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
    Stub-End Female
    1/2
    		1/2
    		Flat3 1/2"1/2"5/8"42 3/8"150
    		Steel285 psi @ 72° F150 psi @ 300° F68095K422000000
    3/4
    		3/4
    		Flat3 7/8"1/2"5/8"42 3/4"150
    		Steel285 psi @ 72° F150 psi @ 300° F68095K38500000
    1
    		1
    		Flat4 1/4"1/2"5/8"43 1/8"150
    		Steel285 psi @ 72° F150 psi @ 300° F68095K38600000
    1 1/4
    		1 1/4
    		Flat4 5/8"1/2"5/8"43 1/2"150
    		Steel285 psi @ 72° F150 psi @ 300° F68095K38700000
    1 1/2
    		1 1/2
    		Flat5"1/2"5/8"43 7/8"150
    		Steel285 psi @ 72° F150 psi @ 300° F68095K38800000
    2
    		2
    		Flat6"5/8"3/4"44 3/4"150
    		Steel285 psi @ 72° F150 psi @ 300° F68095K38900000
    2 1/2
    		2 1/2
    		Flat7"5/8"3/4"45 1/2"150
    		Steel285 psi @ 72° F150 psi @ 300° F68095K39100000
    3
    		3
    		Flat7 1/2"5/8"3/4"46"150
    		Steel285 psi @ 72° F150 psi @ 300° F68095K39200000
    4
    		4
    		Flat9"5/8"3/4"87 1/2"150
    		Steel285 psi @ 72° F150 psi @ 300° F68095K39300000
    6
    		6
    		Flat11"3/4"7/8"89 1/2"150
    		Steel285 psi @ 72° F150 psi @ 300° F68095K39400000
    8
    		8
    		Flat13 1/2"3/4"7/8"811 3/4"150
    		Steel285 psi @ 72° F150 psi @ 300° F68095K421000000
     
    Stub-End Straight Adapters
    Image of Product. Straight Adapter. Front orientation. Pipe Stub Ends. Low-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
    1/2
    		1 3/8"Seamless40
    		Steel43425K115000000
    3/4
    		1 11/16"Seamless40
    		Steel43425K12500000
    1
    		2"Seamless40
    		Steel43425K13500000
    1 1/4
    		2 1/2"Seamless40
    		Steel43425K145000000
    1 1/2
    		2 7/8"Seamless40
    		Steel43425K155000000
    2
    		3 5/8"Seamless40
    		Steel43425K165000000
    2 1/2
    		4 1/8"Seamless40
    		Steel43425K175000000
    3
    		5"Seamless40
    		Steel43425K185000000
    4
    		6 3/16"Seamless40
    		Steel43425K215000000
    6
    		8 1/2"Seamless40
    		Steel43425K235000000
    8
    		10 5/8"Seamless40
    		Steel43425K245000000
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