What is a Mass Flow Meter?

What are a flow meter and a mass flow meter?

A flow meter is a tool for determining the volume or mass of a gas or liquid. Flow meters are called by a variety of names depending on the application or functionality, including flow gauge, flow indicator, liquid meter, flow rate sensor, and so on.

A mass flow meter, also known as an inertial flow meter, measures the mass flow rate of a fluid flowing through a tube. The mass flow rate is defined as the mass of a fluid passing through a fixed point in one unit of time.

Why is flow measurement or monitoring required?

Flow monitoring is, without a doubt, one of the most common duties in any industrial setting. A variety of industrial processes need flow measurement of different liquids or gases for different reasons. These include billing the user, accurate metering to mix exact quantities, avoiding waste, filling the exact volume of gas or liquid in containers, custody transfer, and so on.

Is flow measurement or monitoring easy?

Often, it is difficult to ensure correct flow measurement. It begins with design challenges. Then there are installation issues while ensuring a good metering system. No matter how well-designed a flow metering system is, if it is not installed according to best practices, the flow meter will not function as expected in terms of dependability, performance, and accuracy.

More attention is necessary during installation in custody transfer applications such as steam condensate flow measurement. If it is not taken in the recommended format, the flow meter may not function properly or with the manufacturer’s stated accuracy. Although accuracy is not very critical in non-custody transfer applications, the repeatability of fine flow meter operation is necessary. During installation, some attention and maintenance are also required, or it may not work for many years.

Mass Flow Meter Installation

1. Dos and Don’ts:

• Ensure that the power supply provided is stable, noise-free, and within the specified tolerance.
• Ensure that the direction of flow matches the arrow indicating the flow direction on the flow tube.
• Do not install the flow meter in a place subjected to intense vibrations. Install the flow meter where no vibrations are present.
• Use proper snubber circuits across the coils of the switchgear assemblies near the transmitter. Do not intermix the cable with the power cable. The minimum distance between the signal cable and the power cable should be greater than 12 inches.
• The installation of the flow meter should be as far away as possible from heavy electrical loads.
• Ensure the load connected across the output terminal is within specifications.
• Ensure that the transmitter mounting screws and the lid screws for the transmitter are always tightened properly to maintain the specified ingress protection class (IP rating).
• Ensure that there is no leakage on the inlet side or outlet of the installed flow meter.

2. Specific pipe requirements: 

• The pipe should be with the correct gasket
• Flanges and gaskets to be correctly aligned
• It is to be ensured that the pipe is clean after installation
• Ensure that there are no leakages in the pipeline
• It is advised that the pipelines be painted or provided with protective chemicals according to the instructions given by the pipe manufacturer to ensure long life and leakage-free operation

3. Inlet and outlet runs-

To maintain the accuracy stipulated in the specification sheets, the sensor must be inserted in the center of a straight pipe section with an undisturbed flow progression. An undisturbed flow progression is achieved if the sections in front of the sensor (inlet) and behind the sensor(outlet) are sufficiently long, straight, and without any obstructions such as edges, seams, curves, etc. Therefore, it is necessary to ensure the recommended inlet and outlet run as per the flow meter manufacturer’s instructions.

For more information on Manas flowmeter please check- https://manasmicro.com/thermal-mass-flow-meter/. Also, we provide installation and commissioning services for the same. Write us at digimark@manasmicro.com