Flow Measurement

JetsFlow | Orifice Plates | Flow Measurement Product Manufacturer

Hole Plate Flow Calculations and Design

One of the key challenges when dealing with flow measurement using differential pressure flow yards is the style of the primary flow component such as an orifice plate, flow nozzle, venturi or other differential producer. The design of an orifice platter or any other movement meter starts with the accumulation of several data items. These data factors are then used to design physical dimensions of the orifice plate including the outer diameter, the platter thickness, the handle requirements, and the orifice bore. Process data are being used in a calculation iteration to develop the orifice bore, and once the physical dimensions of the hole are decided, this information can now be used to complete the overall flow calculation. Worksheets are often applied to order to accumulate the needed data for the flow calculation. Sample worksheets can be obtained from online sources including those at the end of this quick.

The flow calculation will take into consideration all of the process flow conditions and the physical characteristics of the orifice dish. It then provides key results flow measurement as relieve coefficient, beta ratio, flow velocity, expected differential pressure, total pressure loss, etc. The flow calculation also takes into consideration modification factors such as temperature compensation, compressibility factors, liquid properties and other parameters to ensure the most highly accurate instrument possible.

There are many conditions that are being used for the basic flow calculation. A few of the common conditions are: flow calculation data sheet, flow calculation, lose interest calculation; orifice bore computation, orifice data sheet, etc. For that purposes in this brief, the outcome of this process will be referred to as the Flow Calculation.

Once the flow calculation is complete, the physical attributes of the flow meter can be designed. There are many standard making authorities who may have developed guidelines for the physical design of primary circulation meters such as orifice plates. These include ASME MFC-3M, ISO 5167, AGA 3, Performance Test Program code 6 and Performance Analyze Code 19. 5. Dependent on the details of these standards, the physical advantages of the meter such as bore design, lose interest location, pressure tap design, pressure tap location, required pipe straight run requirements, flow conditioning requirements, pipe material, pipe thickness, etc., can be determined.

These physical attributes are accumulated into an engineering design drawing which is utilized for the manufacture of the orifice plate or other flow meter. The merchandise is then produced with very tight tolerances. In the circumstance of a Performance Analyze Code 6 Nozzle, deviations in measured bores as small as 3/1000th of the inch can lead to a meter that satisfies the code requirements and one which does not. As such the manufacturing process is tightly managed and detailed measurements are delivered to ensure that the flow meter will perform as you expected.

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