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    34 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.

    Low-Pressure Stainless Steel Threaded Pipe Flanges

    Also known as Pressure Class 150 flanges, these are designed for low-pressure pipe applications. 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 within a line.
    Cast Flanges
    Image of Product. Front. Front orientation. Pipe and Fittings. Low-Pressure Stainless Steel Threaded Pipe Flanges, Cast Flanges, Flanged Fitting Connection, Threaded Fitting Connection, Female, Flat Surface.
    Image of Product. Flat Surface on Back. Back orientation. Pipe and Fittings. Low-Pressure Stainless Steel Threaded Pipe Flanges, Cast Flanges, Flanged Fitting Connection, Threaded Fitting Connection, Female, Flat Surface.

    Front

    Flat

    Surface on

    Back

    Cast flanges are also called MSS flanges.
    304 Stainless Steel—Flanges hold up in humid, damp, and washdown environments but will corrode if exposed to salt water or chemicals.
    316 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
    Stainless Steel
    316
    Stainless Steel
    (A)
    (B)
    Flanged Connection
    Surface (B)
    Flange
    OD
    For Bolt
    Dia.
    Dia.
    No.
    Of
    Bolt Circle
    Dia.
    Pressure
    Class
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    Each
    NPT Female
    1/2
    		1/2
    		Flat3 1/2"1/2"0.625"42 3/8"150
    		230 psi @ 72° F150 psi @ 360° F43505K35100000043615K561000000
    3/4
    		3/4
    		Flat3 7/8"1/2"0.625"42 3/4"150
    		230 psi @ 72° F150 psi @ 360° F43505K3520000043615K56200000
    1
    		1
    		Flat4 1/4"1/2"0.625"43 1/8"150
    		230 psi @ 72° F150 psi @ 360° F43505K3530000043615K56300000
    1 1/4
    		1 1/4
    		Flat4 5/8"1/2"0.625"43 1/2"150
    		230 psi @ 72° F150 psi @ 360° F43505K3540000043615K56400000
    1 1/2
    		1 1/2
    		Flat5"1/2"0.625"43 7/8"150
    		230 psi @ 72° F150 psi @ 360° F43505K3550000043615K565000000
    2
    		2
    		Flat6"5/8"0.75"44 3/4"150
    		230 psi @ 72° F150 psi @ 360° F43505K3560000043615K566000000
    2 1/2
    		2 1/2
    		Flat7"5/8"0.75"45 1/2"150
    		230 psi @ 72° F150 psi @ 360° F43505K35700000043615K567000000
    3
    		3
    		Flat7 1/2"5/8"0.75"46"150
    		230 psi @ 72° F150 psi @ 360° F43505K35800000043615K568000000
    4
    		4
    		Flat9"5/8"0.75"87 1/2"150
    		230 psi @ 72° F150 psi @ 360° F43505K35900000043615K569000000
     

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

    Front

    Cast flanges are also called MSS flanges.
    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 Stainless Steel—Flanges hold up in humid, damp, and washdown environments but will corrode if exposed to salt water or chemicals.
    316 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
    Stainless Steel
    316
    Stainless Steel
    (A)
    (B)
    Flanged Connection
    Surface (B)
    Flange
    OD
    For Bolt
    Dia.
    Dia.
    No.
    Of
    Bolt Circle
    Dia.
    Pressure
    Class
    Max. Pressure
    @ Temp.
    Each
    Each
    Slip-On Weld Female
    1/2
    		1/2
    		Flat3 1/2"1/2"5/8"42 3/8"150
    		230 psi @ 72° F43505K34100000043615K551000000
    3/4
    		3/4
    		Flat3 7/8"1/2"5/8"42 3/4"150
    		230 psi @ 72° F43505K3420000043615K55200000
    1
    		1
    		Flat4 1/4"1/2"5/8"43 1/8"150
    		230 psi @ 72° F43505K3430000043615K55300000
    1 1/4
    		1 1/4
    		Flat4 5/8"1/2"5/8"43 1/2"150
    		230 psi @ 72° F43505K3440000043615K55400000
    1 1/2
    		1 1/2
    		Flat5"1/2"5/8"43 7/8"150
    		230 psi @ 72° F43505K3450000043615K555000000
    2
    		2
    		Flat6"5/8"3/4"44 3/4"150
    		230 psi @ 72° F43505K3460000043615K556000000
    2 1/2
    		2 1/2
    		Flat7"5/8"3/4"45 1/2"150
    		230 psi @ 72° F43505K34700000043615K557000000
    3
    		3
    		Flat7 1/2"5/8"3/4"46"150
    		230 psi @ 72° F43505K34800000043615K558000000
     
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