A quick note on availability: While you can find older, out-of-copyright editions (like the 1950s/60s versions) floating around as scanned PDFs,
: A pivotal moment in the manual's "deep story" was the integration of data based on Lewis F. Moody’s 1944 paper, "Friction Factors for Pipe Flow" hydraulic institute pipe friction manual pdf
Without the HI manual, you might use outdated roughness or ignore temperature effects on viscosity, leading to a 20% error. A quick note on availability: While you can