Mass flowmeter is an important flow measurement instrument. It is widely used in many fields to directly measure the medium passing through the flowmeter and indirectly measure the medium temperature with the densitometer. It mainly has two types: direct type and indirect type. What are the characteristics of indirect type flowmeter?

①When selecting mass flow meter, we should first consider whether to use direct type or indirect type, which can be considered according to the performance characteristics, scope of application, accuracy requirements and cost of the two mass flow meters.

②For liquid flow measurement, density volume flow method, temperature volume flow method or double flowmeter method can be used. Generally, the pressure correction is not needed, because the influence on the liquid density can be ignored in the normal range of pressure variation.

③The adaptability of the selected densimeter to the measured fluid should be considered when using the density volume flow method. There are two connection methods for the fluid density in the pipeline at the inspection side of the densimeter. One is to insert the densimeter directly into the pipeline. The other is to connect the densimeter to the branch pipe of the main pipe.

④Due to the small range of differential pressure flowmeter in the dual flowmeter method, the application range is affected, but the dual flowmeter method can solve the problem that there is no suitable densimeter when measuring gas.

⑤When it is used to measure gas, the pressure / temperature volume flow method is the most common.

Because there are many kinds of mass flow meters, such as flow computer, flow display totalizer with calculation function, intelligent flow totalizer, etc., the functions are very different, so the detailed information should be obtained from the manufacturer when selecting. Some models are only suitable for the measurement of near ideal gases such as air, while some can use natural gas and steam.