Calculate pressure drop, outlet pressure and allowable normalised flow for a pneumatic hose and fittings.
Complete the inputs and calculate.
Estimate velocity, Reynolds number and line loss including fittings.
Flow, line length and diameter, pressure, temperature, density/viscosity and sum of local loss coefficients.
For the same normalized air flow, actual velocity rises when pressure or cross-section falls. A hose can therefore fit the connector yet slow the cylinder because of velocity, friction or fittings.
Darcy-Weisbach is used; laminar flow uses λ = 64/Re and turbulent flow a Colebrook approximation. Pressure and temperature refer to inlet state.
Smaller lines raise velocity and loss, so nominal size should not be selected from connector thread alone.
Sources and limits: ISO 4414 and ISO 6358 terminology and test context; add leakage and valve curves.
Estimate velocity, Reynolds number and line loss including fittings.
Pneumatics uses compressed air as the working medium. Force and speed depend on piston area and pressure as well as compressible air volume, normalized flow and valve characteristics.
Darcy-Weisbach is used; laminar flow uses λ = 64/Re and turbulent flow a Colebrook approximation. Pressure and temperature refer to inlet state.
Flow, line length and diameter, pressure, temperature, density/viscosity and sum of local loss coefficients. For the same normalized air flow, actual velocity rises when pressure or cross-section falls. A hose can therefore fit the connector yet slow the cylinder because of velocity, friction or fittings.
Enter flow, line length and diameter, operating pressure, temperature and the sum of local loss coefficients. The calculator determines flow velocity, Reynolds number and the resulting pressure loss.
Smaller lines raise velocity and loss, so nominal size should not be selected from connector thread alone.
For the same normalized air flow, actual velocity rises when pressure or cross-section falls. A hose can therefore fit the connector yet slow the cylinder because of velocity, friction or fittings. Normalized flow is air flow converted to reference conditions. It is not the geometric chamber volume, so small lines or valves can strongly limit real cycle time.
Flow in l/min or m³/h, length and diameter in millimetres or metres, pressure in bar, pressure loss in bar or mbar.
Checking whether a planned line causes an acceptable pressure loss to the consumer at a given flow, or sizing line diameter for a new pneumatic system.
ISO 4414 and ISO 6358 terminology and test context; add leakage and valve curves.
Common mistake: Don't select line size from connector thread alone – too small a nominal diameter noticeably raises velocity and pressure loss even if it matches the thread. Pressure and temperature refer to the line's inlet state; at a significantly different operating pressure, air density and therefore loss change.
At the same flow, velocity rises inversely with the square of diameter; pressure loss in turn grows with the square of velocity, so both effects compound.
Air is compressible; density, and therefore velocity and loss, depend on local pressure and temperature, which can change slightly along the line.
Only if their loss coefficients are included in the sum of local losses; for specific components, manufacturer curves usually give more accurate values.
Pressure drop is estimated with Darcy-Weisbach, a friction factor, and local losses at inlet conditions.
Results are preliminary engineering estimates. Manufacturer curves, loads, temperature, leakage, cushioning, and the complete safety and pressure-equipment assessment remain separate.
ISO 1219-1 and ISO 6358-1 provide symbols, terminology, and test-method context; ISO 4414 is used as a safety context. No standards compliance is certified.