CALCULATING FLOW VELOCITY
When designing a metal hose assembly, flow velocity should be taken into consideration.
Click here to use our Flow Velocity Calculator
Flow Velocity is given by:
= Flow Velocity
= Volumetric Flow Rate
= Medium Density
The Flow Velocity in a corrugated metal hose should never exceed 45m/sec for gas or 23m/sec for liquids. High Velocities can force the corrugations into resonant vibration; this can result in premature failure – such failures can be prevented through the use of an internal liner or change in the nominal size. The critical speed is mostly influenced by the medium conveyed and its working conditions, the shape of the corrugations and hose bending. It can start from 5m/s for liquids and 30m/s for gases. For higher values, it is intended that the manufacturer be consulted. (BS EN ISO 10380-2012)
This chart illustrates that Velocity varies with regards to whether the metal hose has a bend in it.
|MEDIA||HOSE ALIGNMENT||MAXIMUM VELOCITY
(without Liner) m/sec
|Liquid||45 deg Bend||17|
|Liquid||90 deg Bend||11|
|Gas||45 deg Bend||34|
|Gas||90 deg Bend||23|