Flow Measurement

Description:

Our experience in flow measurement has been gained over several years and encompasses many of the flow measurement technologies available today. Our expertise are concentrated in three main areas, Absolute flow measurement, Comparative flow measurement and Mass flow measurement.

Specifications:

Flow Range:	0-500 L/min
Pressure Range:	0-3000 bar
Back Pressure:	Up to 200 bar
Temperature Range:	Ambient to 150°C
Viscosity Range:	0.8 to 120 cSt

Absolute Flow Measurement

This is the most common form of flow measurement and involves measuring the flow rate and determining an absolute value for it. The flow meter/machine must be calibrated so the reading given by the equipment is meaningful. This method uses proprietary flow meters, calibrated and traceable to National Standards, incorporated into pressure and temperature control systems to measure the flow. Numerous types of meter are available some of which have specific advantages over others in some applications and for some fluids.

DP 500 Flow Test Machine Fixture

Comparative Flow Measurement

This form of flow measurement does not give an absolute flow measurement but a comparative measurement. It involves producing master components on an absolute flow measurement or mass flow measurement device and then using those to calibrate the machine. The master components are flowed on the machine which is then registered to what the flow rates are (as determined by the absolute measurement device). A high and a low master are used to give points at either end of the measuring range and so provide a calibrated range over which measurements may be taken.
Pressure is generated by a falling mass where the time taken for the mass to fall a known distance is proportional to the flow rate of the nozzle. By recording this time for the high and low masters and measuring it for a test component, the flow rate of the test component is determined by comparison to the master values.
The big advantage of this type of flow measurement is that all other factors that would influence the flow reading (fluid density, fluid temperature etc), are taken into account when the machine is mastered. Providing the machine is mastered regularly and the masters themselves are correct the machine will continue to provide accurate comparative measurements.

Flow Comparator

Mass Flow Measurement

This means of flow measurement is the definitive standard by which flow measurement devices themselves are calibrated. It uses first principles to calculate the rate of flow through a component. Mass flow measurement is used mainly where very accurate measurements are required and long cycle times are acceptable. The main draw back is that continuous flow measurement is not possible.
Fluid is flowed through the component for a known period of time and collected. The mass of the fluid collected is measured and then the flow rate determined using the relationship between density, mass and volume.

Mass Flow Measurement Machine