Valves, tees, and elbows introduce turbulence that causes additional pressure drops. This is accounted for using the method or the Resistance Coefficient ( ) method:
The final pipe inside diameter (ID) is a function of the chosen schedule. This true ID is often different from the initial tentative ID used in the hydraulic calculation. The engineer must now re-run the hydraulic analysis (steps 1 and 2) using this final ID to confirm that the velocity and pressure drop are still acceptable. Only when both the hydraulic and mechanical requirements are satisfied is the design considered complete.
(density, viscosity, vapor pressure) at operating and design temperatures.
What (e.g., Carbon Steel, Stainless Steel) are you planning to use?
Power Piping (Steam generation stations, industrial plants). Calculating Wall Thickness (ASME B31.3 formula) To determine the minimum required wall thickness (
The and its operating state (liquid, gas, or two-phase)
Compute actual velocity and Reynolds number.
: Utilizing friction factor correlations based on pipe roughness and Reynolds number. CEDengineering.com 2. Line Sizing Methodology
= Darcy friction factor (determined using the or the Colebrook-White equation ) = Equivalent length of the piping run ( = Acceleration due to gravity ( Minor Losses in Fittings and Valves
Ltotal=Lstraight+∑Leqcap L sub t o t a l end-sub equals cap L sub s t r a i g h t end-sub plus sum of cap L sub e q end-sub 3. Process Piping Line Sizing Methodology
Characterized by chaotic fluid motion, eddies, and rapid mixing. Most industrial process piping operates in the turbulent regime. The Reynolds Number (
: Key goals include maintaining safety, flexibility, maintainability, and economic efficiency. 2. Hydraulic Sizing Principles
): Extra thickness added to guarantee the pipe meets its design life despite predictable metal loss.
The friction factor depends on both the Reynolds number and the relative roughness (
Use the design volumetric flow rate ( ) and the maximum allowable velocity ( vmaxv sub m a x end-sub ) to find the minimum internal cross-sectional area:
