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)
    7 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

    Performance

    Performance

    Low-Pressure Stainless 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.
    Forged Flanges
    Image of Product. Front. Front orientation. Pipe and Fittings. Low-Pressure Stainless Steel Unthreaded Pipe Flanges, Forged Flanges, Butt Weld, Raised Surface.
    Image of Product. Front. Front orientation. Pipe and Fittings. Low-Pressure Stainless Steel Unthreaded Pipe Flanges, Forged Flanges, Slip-On Weld Female, Raised Surface.

    Front

    Front

    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.
    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
    Bolt
    Hole
    304/304L
    Stainless Steel
    316/316L
    Stainless Steel
    (A)
    (B)
    Flanged Connection
    Surface (B)
    Flange
    OD, mm
    For Bolt
    Dia., mm
    Dia.,
    mm
    No.
    Of
    Bolt Circle
    Dia., mm
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    Each
    Butt Weld
    4
    		4
    		Raised22016188180230 psi @ 72° F125 psi @ 300° F1442N190000000———0
     
    Slip-On Weld Female
    4
    		4
    		Raised22016188180230 psi @ 72° F125 psi @ 300° F1442N14000000———0
    4
    		4
    		Raised22016188180230 psi @ 72° F145 psi @ 300° F———01458N140000000
     
    Forged Blind Flanges
    Image of Product. Front. Front orientation. Pipe and Fittings. Low-Pressure Stainless Steel Unthreaded Pipe Flanges, Forged Blind Flanges, Flanged, Raised.
    Image of Product. Raised Surface on Back. Back orientation. Pipe and Fittings. Low-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.
    Bolt
    Hole
    304/304L
    Stainless Steel
    Pipe
    Size
    Flanged Connection
    Surface
    Flange
    OD, mm
    For Bolt
    Dia., mm
    Dia.,
    mm
    No.
    Of
    Bolt Circle
    Dia., mm
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    Flanged
    4
    		Raised22016188180230 psi @ 72° F125 psi @ 300° F1442N250000000
     

    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 Product. Butt Weld: Front. Front orientation. Pipe and Fittings. Low-Pressure Iron and Steel Unthreaded Pipe Flanges, Flanges, Butt Weld, Raised Surface.
    Image of Product. Butt Weld: Raised Surface on Back. Back orientation. Pipe and Fittings. Low-Pressure Iron and Steel Unthreaded Pipe Flanges, Flanges, Butt Weld, Raised Surface.
    Image of Product. Slip-On Weld: Front. Front orientation. Pipe and Fittings. Low-Pressure Iron and Steel Unthreaded Pipe Flanges, Flanges, Slip-On Weld Female, Raised Surface.
    Image of Product. Slip-On Weld: Raised Surface on Back. Back orientation. Pipe and Fittings. Low-Pressure Iron and Steel Unthreaded Pipe Flanges, Flanges, Slip-On Weld Female, Raised Surface.

    Butt Weld:

    Front

    Butt

    Weld:

    Raised

    Surface

    on Back

    Slip-On

    Weld:

    Front

    Slip-On

    Weld:

    Raised

    Surface

    on Back

    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.
    Pipe
    Size
    Bolt
    Hole
    (A)
    (B)
    Flanged Connection
    Surface (B)
    Flange
    OD, mm
    For Bolt
    Dia., mm
    Dia.,
    mm
    No.
    Of
    Bolt Circle
    Dia., mm
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    Butt Weld
    4
    		4
    		Raised22016188180Steel
    		230 psi @ 72° F180 psi @ 300° F1132T14000000
     
    Slip-On Weld Female
    4
    		4
    		Raised22016188180Steel
    		230 psi @ 72° F180 psi @ 300° F1132T2300000
     
    Blind Flanges
    Image of Product. Front. Front orientation. Pipe and Fittings. Low-Pressure Iron and Steel Unthreaded Pipe Flanges, Blind Flanges, Flanged, Raised.
    Image of Product. Raised Surface on Back. Back orientation. Pipe and Fittings. Low-Pressure Iron and Steel Unthreaded Pipe Flanges, Blind Flanges, Flanged, Raised.

    Front

    Raised

    Surface

    on Back

    Bolt
    Hole
    Pipe
    Size
    Flanged Connection
    Surface
    Flange
    OD, mm
    For Bolt
    Dia., mm
    Dia.,
    mm
    No.
    Of
    Bolt Circle
    Dia., mm
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    Flanged
    4
    		Raised22016188180Steel
    		230 psi @ 72° F180 psi @ 300° F1132T18000000
     
    back to top