Applied only to rows with no catalogue wall or inside diameter. A bore or wall typed on a row replaces it for that row. Catalogue wall and inside diameter are used when the API returns them.
Sources
Inside diameter is the stored inside diameter, or the stored outside diameter minus twice the stored wall thickness, from the Engineering API. If those facts are absent, enter a wall thickness or a bore. The page computes inside diameter as outside diameter minus twice the wall thickness. It does not substitute a dimension table. A result that uses a wall or a bore you typed is marked as user-entered. When the catalogue later stores a wall or an inside diameter, that stored value is used and the typed wall or bore is not.
Mean velocity is volumetric flow divided by the internal area. Maximum flow is the velocity limit times that area. Unit factors match the PipingDesigners unit converter: 1 in = 0.0254 m, 1 ft = 0.3048 m, 1 US gallon = 0.003785411784 m3, 1 lb = 0.45359237 kg, 1 ft3 = 0.028316846592 m3, 1 cP = 0.001 Pa·s.
Reynolds number is density times velocity times inside diameter, divided by dynamic viscosity. Laminar is below 2300, transitional is 2300 to 4000, and turbulent is above 4000. Those are the conventional Moody-diagram bands, not a code limit and not an API fact.
API RP 14E erosional velocity is Ve = C / sqrt(rho), with rho in lb/ft3 and Ve in ft/s. C is a user input. The starting value is 100. Confirm C against the edition you use. This page converts density into lb/ft3 and reports Ve in ft/s and m/s. It does not switch C to a metric coefficient.
Density and viscosity are user entries. This page does not store a fluid table.
The velocity limit is user-entered. This page does not print a typical velocity band.
Optional pressure drop uses the Darcy–Weisbach equation over 100 m. The friction factor is the Swamee–Jain explicit approximation of Colebrook–White (Swamee and Jain, Journal of the Hydraulics Division, ASCE, 1976), used only for Reynolds number 5000 to 100,000,000 and relative roughness 0.000001 to 0.01. It is not an iterated Colebrook solution. The roughness box starts at 0.045 mm, the rounded commercial-steel value 0.00015 ft. It is a user input. The Engineering API has no roughness fact. Confirm it against the roughness table you use.
Catalogue facts are UNVALIDATED observations unless the API says otherwise.
