Mon. Mar 8th, 2021

Calibration Procedures of Liquid Flowmeter

Calibration Procedures of Liquid Flowmeter

A flow meter is a tool meant to read flow rates of liquid, gas, and any other fluid. A flowmeter is used in many sectors to measure the flow in terms of volume or mass. The speed at which fluids move in pipelines, vessels, or orifices is called a flow rate. Experts who develop flow meters aim to check, control, or read flow rate and tools in speed. 

Flow meters play great roles in flow processes. After a while, these flowmeters need proper resetting from time to time to ensure that they give needed readings. A good example is when a weight scale reads 10lbs when no one is standing on it. This is incorrect reading, which needs to reset to read an initial zero value. For flow meters to maintain correct readings, they need constant resets, just like any other device. 

In this post, we will take you through the process of flow meter calibration and explain to you the reason behind regular flowmeter calibration. Read on for more insights. 

What is Flowmeter Calibration?

The preset scale checking flow meters to ensure that they give out correct reading based on stated liquid flow measurement standards is called calibration. This process is vital in many sectors that deal with liquids and gases such as gas, oil, and water. In flow meter calibration, flow meters are put through several tests focused on checking and comparing their readings to comply with given needed standards. 

Many flowmeter makers choose to reset their meters after production. Others may decide to send their flow meters to independent calibration facilities to be checked and reset.

Difference Between Flow Meter Calibration and Recalibration

Flowmeter calibration is the process of comparing different readings from a given liquid flow measurement while it’s operational. The readings are supposed to match with the set up standard flow readings. If they don’t, the device is fixed to meet up to the needed standards. Flowmeter calibration is meant to test and adjust flow meters that have just been produced and not yet in use. 

On the other hand, flowmeter recalibration is to reset a flow meter that is already in use. Flow meters should be recalibrated once in a while since they tend to go ‘out of phase’ after being used for long. What sets apart these two is that calibration is done before the meter is released out in the market. On the other hand, recalibration is done after a flow meter has been used for a while. It is done a couple of times in a flow meter’s lifespan. Various software can be used to check if the meter is giving correct readings once again.

Calibration Process of Flow Meters

There are many ways to reset a flow meter. All these ways are meant to make a flow meter conform to the standards. The process involves comparing and adjusting flow meters under a couple of tests to meet the set liquid flow measurement standards. Calibration in the U.S. is obtained from the National Institute of Standards and Technology (NIST). Calibration standard in Europe comes from the Netherlands in the Van Swinden Laboratory.

The most commonly used preset process in flow meters include. 

  • Master Meter
  • Gravimetric 
  • Piston Prover 

Master Meter Calibration 

In the master meter process, readings from a flow meter are compared under test. You compare between the flow meter that needs calibration and the ‘master’ flow meter that has undergone calibration. The master flow meter works and gives correct readings. The master flow meter readings meet the national or international standards. If you want to use this method to calibrate your flow meter, you need to follow the steps you need to follow. 

  • Put the flow meter that requires calibration in series with the master flow meter. 
  • Use the measured flow volume of liquid from the master meter and the flow meter that requires calibration to compare the readings. 
  • Confirm the flow meter tested by calibrating it to give the same reading as the master meter. 

Gravimetric Calibration  

One of the most-effective calibrations with high accuracy levels is gravimetric calibration. It is used to reset flow meters used for water purification, oil, and petrochemical industries. Below are steps that should be followed when using the gravimetric calibration procedure:

· Put a small portion of process fluid in a test meter, and while it flows in about 60 seconds, weigh it for a precise amount of time. 

  • To get a correct reading of the weight of test fluid, use a calibrated scale.
  • Use a discharge container to divert the test fluid after finishing the test period. 
  • Getting the flow rate entails dividing its volumetric weight by the test duration.
  • Compare the flow rate of the flow meter and the calculated flow rate and adjust it to the measured flow rate.

Conclusion

The performance of a flow meter is determined by the maintenance and calibration done to it. Therefore, ensure that your flowmeter is calibrated after a while. Some flow meter manufacturers offer calibration to their customers. Any calibration done to a flow meter should meet the required liquid flow measurement standards.

Author Bio
Naman Modi is a Professional Blogger, SEO Expert & Guest blogger at proteusind.com. He is an Award-Winning Freelancer & Web Entrepreneur helping new entrepreneurs launch their first successful online business.