Module 3 Process Piping Hydraulics Sizing And Pressure Rating Pdf -

: Sizing typically begins with basic fluid flow equations to calculate the necessary ID based on the required flow rate and target velocity.

: This is the most critical parameter for hydraulic calculations. It is derived from the Outside Diameter (OD) and the calculated wall thickness (t).

: As the pipe schedule increases, wall thickness grows to handle higher pressures, reducing the internal diameter. 3. Standards and Safety Factors Process Piping Fundamentals, Codes and Standards : Sizing typically begins with basic fluid flow

Selected for highly corrosive processes, food-grade applications, or cryogenic service. 6. Practical Design Considerations

The friction factor depends on both the Reynolds number and the relative roughness of the pipe ( : As the pipe schedule increases, wall thickness

Manufacturing processes allow pipe walls to vary. For seamless pipe, a standard mill tolerance of is applied. The calculated must be multiplied by 1.1431.143

). Liquid boils, forming vapor bubbles that violently collapse when moving into higher pressure zones, pitting the metal. NPSH Available ( NPSHAcap N cap P cap S cap H sub cap A Class 300) for flanges

= Total allowances, including the (typically 1.5 mm to 3.0 mm) and any thread/groove depths. Tolcap T o l

Once a standard pipe size is selected, you must verify that the pressure drop over the run is within acceptable limits. Darcy-Weisbach Equation The primary method for calculating frictional head loss ( ) in a pipe is:

Furthermore, the overall pressure rating of a system is determined by its weakest component. While the pipe wall may be rated for a certain pressure, the flanges, valves, and fittings must be rated to the same or higher standard. For instance, ASME B16.5 dictates standard pressure classes (e.g., Class 150, Class 300) for flanges, which must be selected to match the system's design conditions.