Flow Measurement Instrumentation Interview Questions and Answers

 Flow Meter Questions and Answers

1. What are the major three methods of flow meters?
Area flow meter
Mass flow meter
Quantity meters
2. List some examples of the inferential flow meter.
In the inferential type of flow metering techniques, the out quantity flow rate is inferred from a characteristic effect of a related phenomenon.
Turbine flow meters
Target flow meters
Ultrasonic flow meters
3. What are the different types of positive displacement meters?
Reciprocating piston type
Rotating vane type
Nutating disk type
Lobed impellar type
Oscillating piston type
4. What are the different types of thermal flow meters?
Heat transfer flow meters
Hot wire flow meters
5. Name the different types of weighing methods
 Semiconductor feed belt weighing ( Batch weighing)
Continuous conveyor scale
radio active transmission gauge
volumetric solid methods
6. Write any two points of calibration of flow meter
Wet meter – manometer which is calibrated with mercury
Dry meter – manometer which is calibrated with mercury
7. what is Rotameter?
It is an example of a variable area flow meter. When fluid enters lopped moves from the bottom to top. Distance is proportional to the flow rate.
8. Explain the principle of calorimeter flow meter
Consist of two coil type resistance thermometer, the difference of temperature between the thermometer is maintained constant.
9. Explain the principle of turbine flow meter
when the liquid enters through the inlet, due to the inflow, the shaft rotates which cuts the magnetic pickup, and produces the voltage which is proportional to the inflow of water.
10. List the advantages & disadvantages of turbine flow meter
  • Better Accuracy [± 0.25% to ± 0.5%].
  • It provides excellent repeatability [± 0.25% to ± 0.02%] and rangeability (10 : 1 and 20 : 1).
  • It has fairly low pressure drop.
  • It is easy to install and maintain.
  • It has good temperature and pressure ratings.
  • It can be compensated for viscosity variation.
  • It is not suitable for non-lubricating fluids.
  • They cannot maintain its original calibration over a very long period and therefore periodical recalibration is necessary.
  • limited use for slurry application
  • They are sensitive to changes in the viscosity of the liquid passing through the meters.
  • They are sensitive to flow disturbances.
  • Due to high bearing friction is possible in small meters, they are not preferred well for low flowrates.