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    8 Products
    About Measuring Fittings
    industrial info icon

    Measure the threaded ends of your fittings to identify their pipe size, thread size, schedule, and thread type. Then, find compatible components.

    Flange-Mount Orifice Valves

    Also known as orifice plates, these mount between orifice flange unions. They are used to throttle, vent, bleed, or regulate the flow of liquids and gases.
    304 Stainless Steel Body
    Image of Product. Front orientation. Orifice Valves. Flange-Mount Orifice Valves.
    For
    Orifice Flange
    Handle
    Orifice
    Dia.
    Water Flow
    Airflow @
    Pressure
    For Flange
    Pipe Size
    For Pipe
    Schedule
    ANSI
    Class
    Surface
    Lg.
    Thk.
    OD
    Ht.
    Wd.
    For Use With
    Max. Pressure
    @ Temp.
    Temp. Range,
    ° F
    Each
    0.525"9.9 gpm @ 40 psi71.2 scfm @ 40 psi1
    		40
    		300
    		Raised7 7/8"1/8"2 7/8"5"1 1/2"Air, Argon, Carbon Dioxide, Helium, Neon, Nitrogen, Oil, Water, Xenon740 psi @ 100° F-20 to 9502206N130000000
     

    Orifice Valves for Water

    Image of Product. Front orientation. Orifice Valves. Orifice Valves for Water.
    Also known as flow restrictors and precision orifice valves, these orifices are used to throttle, vent, bleed, or regulate flow in water systems. They automatically adjust to changing inlet pressure to maintain consistent outlet flow.
    Nickel-Plated Brass Body—Nickel-plated brass orifices are more corrosion resistant than orifices with a plain brass body.
    316 Stainless Steel Body—316 stainless steel orifices have the best corrosion resistance.
    Pipe
    Size
    Lg.
    Max. Pressure
    @ Temp.
    Temp. Range,
    ° F
    Choose an Outlet Water Flow
    Each
    Nickel-Plated Brass Body
     
    NPT Female × NPT Female
    12 3/4"200 psi @ 180° F33 to 1801 gpm, 2 gpm, 3 gpm, 4 gpm, 5 gpm, 6 gpm, 8 gpm, 10 gpm, 12 gpm, 15 gpm, 20 gpm, 25 gpm, 30 gpm4762K47000000
     
    316 Stainless Steel Body
     
    NPT Female × NPT Female
    12 3/4"200 psi @ 180° F33 to 1801 gpm, 2 gpm, 3 gpm, 4 gpm, 5 gpm, 6 gpm, 8 gpm, 10 gpm, 12 gpm, 15 gpm, 20 gpm, 25 gpm, 30 gpm4762K57000000
     

    Pressure-Compensating Threaded Orifice Valves

    Image of Product. NPT Female × NPT Female. Front orientation. Orifice Valves. Pressure-Compensating Threaded Orifice Valves, NPT Female × NPT Female.

    NPT Female × NPT

    Female

    When inlet pressure changes, these orifices automatically adjust to deliver a consistent outlet flow. They connect to threaded pipe, or fit into threaded holes. Also known as flow restrictors and precision orifice valves, they are commonly used to regulate the flow of water during treatment.
    Pipe
    Size
    Lg.
    For Use
    With
    Max. Pressure
    @ Temp.
    Temp. Range,
    ° F
    Water Flow
    Each
    Buna-N Body
     
    NPT Female × NPT Female
    1
    		2 1/2"Water120 psi @ 140° F40 to 1405 gpm @ 120 psi2264N31000000
     

    Flange Unions

    Measure, throttle, and regulate the flow of liquids and gases in your line by adding an orifice plate to these unions. They consist of two flange halves, plus all of the components needed to connect them together. Tighten the jack bolts to separate the flange halves to inspect or replace the orifice plate.
    To throttle flow, mount an orifice plate between the two flanges. The orifice plate restricts the flow in order to regulate it.
    To measure flow, build the same assembly, except you’ll also connect a differential pressure gauge or transmitter to both flange halves using the threaded ports. Your gauge or transmitter will measure the difference between the pressure before and after the orifice plate. The pressure difference is proportional to flow rate, so you can use that measurement to calculate your line’s flow rate.
    Butt Weld × Flanged
    Image of Product. Assembled. Front orientation. Orifice Valves. Flange Unions, Butt-Weld Fitting Connection.
    Image of Product. Exploded. Front orientation. Exploded view. Contains Annotated. Orifice Valves. Flange Unions, Butt-Weld Fitting Connection.

    Assembled

    Exploded

    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.
    For 316/316L Stainless Steel Fittings—316/316L stainless steel flanges have excellent corrosion resistance.
    ASME B16.36—Flanges that meet ASME B16.36 adhere to specifications and testing requirements for temperature and pressure ratings, dimensions, materials, and tolerances.
    Bolt
    Hole
    Port
    For Carbon
    Steel Fittings
    For 316/316L
    Stainless Steel Fittings
    Pipe
    Size
    Construction
    Flange
    OD
    For Bolt
    Dia.
    Dia.
    No.
    of
    Bolt Circle
    Dia.
    Pipe
    Size
    No.
    of
    Includes
    Specs. Met
    For Use With
    Temp.
    Pressure
    Class
    For Pipe
    Material
    Each
    For Pipe Material
    Each
    1Seamless4 7/8"5/8"11/16"43 1/2"1/2
    		2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    		Carbon Steel5291N120000000316/316L Stainless Steel
    		5291N250000000
    Slip-On Weld × Flanged
    Image of Product. Assembled. Front orientation. Orifice Valves. Flange Unions, Slip-on-Weld Fitting Connection.
    Image of Product. Exploded. Front orientation. Exploded view. Contains Annotated. Orifice Valves. Flange Unions, Slip-on-Weld Fitting Connection.

    Assembled

    Exploded

    Slip-on weld flanges have no internal stop; slide a pipe through the flange and weld on both sides.
    For 316/316L Stainless Steel Fittings—316/316L stainless steel flanges have excellent corrosion resistance.
    ASME B16.36—Flanges that meet ASME B16.36 adhere to specifications and testing requirements for temperature and pressure ratings, dimensions, materials, and tolerances.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Bolt
    Hole
    Port
    For Carbon
    Steel Fittings
    For 316/316L
    Stainless Steel Fittings
    Pipe
    Size
    Flange
    OD
    For Bolt
    Dia.
    Dia.
    No.
    of
    Bolt Circle
    Dia.
    Pipe
    Size
    No.
    of
    Includes
    Specs. Met
    For Use With
    Temp.
    Pressure
    Class
    For Pipe
    Material
    Each
    For Pipe Material
    Each
    14 7/8"5/8"11/16"43 1/2"1/2
    		2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    		Carbon Steel5291N180000000316/316L Stainless Steel
    		5291N320000000
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