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    23,533 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.
    Forged Flanges
    Image of Product. Front. Front orientation. Pipe and Fittings. Low-Pressure Stainless Steel Threaded Pipe Flanges, Forged Flanges, Flanged Fitting Connection, Threaded Fitting Connection, Female, Raised Surface.
    Image of Product. Raised Surface on Back. Back orientation. Pipe and Fittings. Low-Pressure Stainless Steel Threaded Pipe Flanges, Forged Flanges, Flanged Fitting Connection, Threaded Fitting Connection, Female, Raised Surface.

    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.
    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.
    Alloy 20 Stainless Steel—Flanges have the best corrosion resistance of all the stainless steel flanges we offer. Alloy 20 stainless steel is also known as Carpenter 20 and resists cracking from stress and corrosion.
    Pipe
    Size
    Bolt
    Hole
    304/304L
    Stainless Steel
    316/316L
    Stainless Steel
    Alloy 20
    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
    Each
    NPT Female
    1/2
    		1/2
    		Raised3 1/2"1/2"0.62"42 3/8"150
    		290 psi @ 72° F200 psi @ 360° F———0———02698K610000000
    1/2
    		1/2
    		Raised3 1/2"1/2"0.625"42 3/8"150
    		230 psi @ 72° F150 psi @ 360° F44685K1100000044695K11000000———0
    3/4
    		3/4
    		Raised3 7/8"1/2"0.62"42 3/4"150
    		290 psi @ 72° F200 psi @ 360° F———0———02698K62000000
    3/4
    		3/4
    		Raised3 7/8"1/2"0.625"42 3/4"150
    		230 psi @ 72° F150 psi @ 360° F44685K120000044695K1200000———0
    1
    		1
    		Raised4 1/4"1/2"0.62"43 1/8"150
    		290 psi @ 72° F200 psi @ 360° F———0———02698K63000000
    1
    		1
    		Raised4 1/4"1/2"0.625"43 1/8"150
    		230 psi @ 72° F150 psi @ 360° F44685K130000044695K1300000———0
    1 1/4
    		1 1/4
    		Raised4 5/8"1/2"0.625"43 1/2"150
    		230 psi @ 72° F150 psi @ 360° F44685K140000044695K1400000———0
    1 1/2
    		1 1/2
    		Raised5"1/2"0.62"43 7/8"150
    		290 psi @ 72° F200 psi @ 360° F———0———02698K64000000
    1 1/2
    		1 1/2
    		Raised5"1/2"0.625"43 7/8"150
    		230 psi @ 72° F150 psi @ 360° F44685K150000044695K1500000———0
    2
    		2
    		Raised6"5/8"0.75"44 3/4"150
    		230 psi @ 72° F150 psi @ 360° F44685K160000044695K1600000———0
    2
    		2
    		Raised6"5/8"0.75"44 3/4"150
    		290 psi @ 72° F200 psi @ 360° F———0———02698K65000000
    2 1/2
    		2 1/2
    		Raised7"5/8"0.75"45 1/2"150
    		230 psi @ 72° F150 psi @ 360° F44685K1700000044695K17000000———0
    3
    		3
    		Raised7 1/2"5/8"0.75"46"150
    		230 psi @ 72° F150 psi @ 360° F44685K1800000044695K18000000———0
    4
    		4
    		Raised9"5/8"0.75"87 1/2"150
    		230 psi @ 72° F150 psi @ 360° F44685K1900000044695K19000000———0
    6
    		6
    		Raised11"3/4"0.875"89 1/2"150
    		230 psi @ 72° F150 psi @ 360° F44685K2100000044695K21000000———0
    8
    		8
    		Raised13 1/2"3/4"0.88"811 3/4"150
    		230 psi @ 72° F150 psi @ 360° F44685K32100000044695K25000000———0
     
    BSPT Female
    1/2
    		1/2
    		Raised3 1/2"1/2"0.62"42 3/8"150
    		230 psi @ 72° F150 psi @ 360° F1384N1100000———0———0
    3/4
    		3/4
    		Raised3 7/8"1/2"0.62"42 3/4"150
    		230 psi @ 72° F150 psi @ 360° F1384N1200000———0———0
    1
    		1
    		Raised4 1/4"1/2"0.62"43 1/8"150
    		230 psi @ 72° F150 psi @ 360° F1384N1300000———0———0
    2
    		2
    		Raised6"5/8"0.75"44 3/4"150
    		230 psi @ 72° F150 psi @ 360° F1384N15000000———0———0
     
    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
     
    Forged Reducing Flanges
    Image of ProductInUse. Reducing Flange. Side1 orientation. Contains Annotated. Pipe and Fittings. Low-Pressure Stainless Steel Threaded Pipe Flanges, Forged Reducing Flanges, Flanged Fitting Connection, Threaded Fitting Connection, Female, Raised Surface.
    Image of Product. Front. Front orientation. Pipe and Fittings. Low-Pressure Stainless Steel Threaded Pipe Flanges, Forged Reducing Flanges, Flanged Fitting Connection, Threaded Fitting Connection, Female, Raised Surface.
    Image of Product. Raised Surface on Back. Back orientation. Pipe and Fittings. Low-Pressure Stainless Steel Threaded Pipe Flanges, Forged Reducing Flanges, Flanged Fitting Connection, Threaded Fitting Connection, Female, Raised Surface.

    Reducing

    Flange

    Front

    Raised

    Surface on

    Back

    Forged flanges have better strength than cast 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.
    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.
    Bolt
    Hole
    304/304L
    Stainless Steel
    316/316L
    Stainless Steel
    Pipe Size
    (A)
    For Flange
    Pipe Size (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
    1/4
    		1
    		Raised4 1/4"1/2"0.62"43 1/8"150
    		230 psi @ 72° F150 psi @ 360° F44685K33100000044695K26000000
    1/2
    		1
    		Raised4 1/4"1/2"0.625"43 1/8"150
    		230 psi @ 72° F150 psi @ 360° F44685K1410000044695K141000000
    1/2
    		1 1/2
    		Raised5"1/2"0.62"43.88"150
    		230 psi @ 72° F150 psi @ 360° F44685K23100000———0
    1/2
    		2
    		Raised6"5/8"0.75"44 3/4"150
    		230 psi @ 72° F150 psi @ 360° F44685K33500000044695K264000000
    1/2
    		3
    		Raised7 1/2"5/8"0.75"46"150
    		230 psi @ 72° F150 psi @ 360° F44685K232000000———0
    1/2
    		4
    		Raised9"5/8"0.75"87 1/2"150
    		230 psi @ 72° F150 psi @ 360° F44685K233000000———0
    3/4
    		1
    		Raised4 1/4"1/2"0.625"43 1/8"150
    		230 psi @ 72° F150 psi @ 360° F44685K1420000044695K142000000
    3/4
    		1 1/2
    		Raised5"1/2"0.62"43 7/8"150
    		230 psi @ 72° F150 psi @ 360° F44685K33300000044695K262000000
    3/4
    		2
    		Raised6"5/8"0.75"44 3/4"150
    		230 psi @ 72° F150 psi @ 360° F44685K33600000044695K265000000
    3/4
    		3
    		Raised7 1/2"5/8"0.75"46"150
    		230 psi @ 72° F150 psi @ 360° F44685K234000000———0
    3/4
    		4
    		Raised9"5/8"0.75"87 1/2"150
    		230 psi @ 72° F150 psi @ 360° F44685K235000000———0
    1
    		1 1/4
    		Raised4 5/8"1/2"0.62"43 1/2"150
    		230 psi @ 72° F150 psi @ 360° F44685K33200000044695K261000000
    1
    		1 1/2
    		Raised5"1/2"0.625"43 7/8"150
    		230 psi @ 72° F150 psi @ 360° F44685K14300000044695K143000000
    1
    		2
    		Raised6"5/8"0.75"44 3/4"150
    		230 psi @ 72° F150 psi @ 360° F44685K14400000044695K144000000
    1
    		2 1/2
    		Raised7"5/8"0.75"45 1/2"150
    		230 psi @ 72° F150 psi @ 360° F44685K236000000———0
    1
    		3
    		Raised7 1/2"5/8"0.75"46"150
    		230 psi @ 72° F150 psi @ 360° F44685K237000000———0
    1
    		4
    		Raised9"5/8"0.75"87 1/2"150
    		230 psi @ 72° F150 psi @ 360° F44685K238000000———0
    1 1/4
    		1 1/2
    		Raised5"1/2"0.62"43 7/8"150
    		230 psi @ 72° F150 psi @ 360° F44685K33400000044695K263000000
    1 1/4
    		2
    		Raised6"5/8"0.75"44 3/4"150
    		230 psi @ 72° F150 psi @ 360° F44685K33700000044695K266000000
    1 1/4
    		4
    		Raised9"5/8"0.75"87 1/2"150
    		230 psi @ 72° F150 psi @ 360° F44685K239000000———0
    1 1/2
    		2
    		Raised6"5/8"0.75"44 3/4"150
    		230 psi @ 72° F150 psi @ 360° F44685K33800000044695K267000000
    Low-Pressure 304/304L Stainless Steel Forged Pipe Flange, Reducer, 1-1/2 NPT x 2 Flange Pipe Size
    EachIn stock
    1 1/2
    		2 1/2
    		Raised7"5/8"0.75"45 1/2"150
    		230 psi @ 72° F150 psi @ 360° F44685K241000000———0
    1 1/2
    		3
    		Raised7 1/2"5/8"0.75"46"150
    		230 psi @ 72° F150 psi @ 360° F44685K242000000———0
    1 1/2
    		4
    		Raised9"5/8"0.75"87 1/2"150
    		230 psi @ 72° F150 psi @ 360° F44685K243000000———0
    2
    		2 1/2
    		Raised7"1/2"0.62"45 1/2"150
    		230 psi @ 72° F150 psi @ 360° F———044695K268000000
    2
    		2 1/2
    		Raised7"5/8"0.75"45 1/2"150
    		230 psi @ 72° F150 psi @ 360° F44685K339000000———0
    2
    		3
    		Raised7 1/2"5/8"0.75"46"150
    		230 psi @ 72° F150 psi @ 360° F44685K14500000044695K145000000
    2
    		4
    		Raised9"5/8"0.75"87 1/2"150
    		230 psi @ 72° F150 psi @ 360° F44685K34100000044695K269000000
    2 1/2
    		3
    		Raised7 1/2"5/8"0.75"46"150
    		230 psi @ 72° F150 psi @ 360° F44685K244000000———0
    2 1/2
    		4
    		Raised9"5/8"0.75"87 1/2"150
    		230 psi @ 72° F150 psi @ 360° F44685K245000000———0
    3
    		4
    		Raised9"5/8"0.75"87 1/2"150
    		230 psi @ 72° F150 psi @ 360° F44685K34200000044695K27000000
    4
    		6
    		Raised11"3/4"0.88"89 1/2"150
    		230 psi @ 72° F150 psi @ 360° F44685K34300000044695K271000000
    6
    		8
    		Raised13 1/2"3/4"0.88"811 3/4"150
    		230 psi @ 72° F150 psi @ 360° F44685K246000000———0
     
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