Do you even need a flowmeter?

Many users often just want to know the rate at which a liquid or gas is moving through a pipeline. In such cases, a simple flow indicator, available from any flowmeter vendor at a fraction of the cost of the simplest flowmeter, will usually suffice. Simple and easy to install and requiring no external power, these instruments can be used to provide local indication of flow.
Even where there is a demand for something more sophisticated, such as an indication of flow to within 10%, there may still be no need to purchase a flowmeter. Many installations typically feature bends or joints that can be readily converted into a crude flowmeter by purchasing a differential pressure transmitter and installing sensors to measure the difference in pressure between two or more points. Provided that calibration can be correctly achieved, these simplified flowmeters can achieve an accuracy of around 5%.  

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