Engineering reference tables
The data a pipe flow calculation actually runs on: loss coefficients, pipe dimensions, wall roughness, empirical coefficients and fluid properties. Every table here is published in full, free, with no account, and every one names where its values came from.
These are not summaries of the data Fluid Network Studio uses. They are that data. Each table is generated from the solver's own arrays when the site is built, so the coefficient you read here is the coefficient the software applies, and neither can quietly drift from the other.
The tables
Pipe fitting K factors (minor loss coefficients)
Minor loss coefficient K for pipe fittings, valves, bends and ducts, with the source named on every row, plus the Kv, Cv and rated-drop conversions.
50 fittings, valves, bends and duct components. Crane TP-410, NASA GFSSP and ASHRAE, named per row
Pipe schedule dimensions: DN, OD, wall and internal diameter
Internal diameter and wall thickness by DN and schedule for ASME B36.10M carbon steel, B36.19M stainless and PE100 to AS/NZS 4130. Every table names its standard.
334 size and schedule combinations, with bore and wall. ASME B36.10M, ASME B36.19M and AS/NZS 4130
Absolute pipe roughness values by material
Absolute wall roughness in mm and m for pipe and duct materials, including aged and corroded conditions, with the sources named and the ranges stated honestly.
28 materials and conditions, in mm and m. Moody roughness classes, Crane TP-410 and ASHRAE
Hazen-Williams C factors by material and condition
Hazen-Williams C coefficients by pipe material and condition, with the SI equation they belong to and where the method stops being valid.
15 material and condition presets. Williams and Hazen as reproduced in Crane TP-410 and AWWA practice
Fluid properties for pipe flow calculations
Density, viscosity, specific heat, conductivity and vapour pressure for common liquids, plus gas constants and real-gas data for gases. Sources named.
25 liquids and 12 gases. Solver correlations for water, published values for the rest
Why every row names a source
Most of the roughness and coefficient tables an engineer finds online carry no attribution at all. They are copied from one site to the next until the origin is untraceable, which is fine right up to the moment someone asks you to justify a number in a design review.
So these tables name their sources, and where a value's provenance is genuinely a range or a manufacturer typical rather than a standard, they say that instead of implying a precision that does not exist. Stainless wall thicknesses that have not been re-checked line by line against the standard are labelled as such. Composition-weighted pseudo-properties for gas mixtures are labelled as such. An honest boundary is more useful than a confident number.
A table, a calculator or a guide
Four kinds of page do four different jobs here, and reaching for the wrong one wastes time.
- A reference table gives you a number to put into a calculation you are already doing, with enough explanation to know whether that number applies to your case.
- A calculator does the arithmetic for one pipe and one question: a pressure drop, a velocity, a Reynolds number, a heat loss.
- An application guide frames a whole design task and tells you how to model it, including the parts that are easy to get wrong.
- A worked example is a complete network you can open in the Studio and re-solve as it stands.
Would rather not look anything up? Open the Studio and pick a material, a fitting, a pipe size or a fluid from these same libraries, then solve the whole network at once. Every value stays editable, so a preset is a starting point rather than a constraint.
How to use tabulated values well
A tabulated value is an engineering starting point, not design data for a specific installation. Three habits are worth more than any table.
- Prefer a measurement to a table. If the system exists and you can get a flow and a pressure difference, back-calculate the roughness or the coefficient. A calibrated value for the actual pipe beats the best handbook figure for its material.
- Check whether it matters at all. Roughness does not appear in laminar friction, fitting losses are often a small share of a long run, and a property you are agonising over may not move the answer. Solve the plausible range and see.
- Design for the pipe you will have. Almost every value here is for new, clean pipe. Metal mains in aggressive water roughen and narrow over a design life, and that change is frequently the largest uncertainty in the whole calculation.
Fluid Network Studio computes steady-state pressures, flows, velocities, temperatures and power from the data you enter. It supports your engineering work rather than replacing it, results should be reviewed by a qualified engineer for the specific application, and no compliance with or certification against any particular standard is claimed. Standards named on these pages are cited to identify the source of a dimension or a coefficient, and the standards themselves remain the authority.