Mass Flow Meters and Controllers

Mass flow meters measure flow rate in units of mass flow, for example, lbs/min.  Mass flow meters can be configured to either measure liquid or gas flow.  Common mass flow meter technology types are thermal meters and Coriolis meters.  Thermal meters use a heated sensing element isolated from the fluid flow path.  The flow stream conducts heat from the sensing element.  The conducted heat is directly proportional to the mass flow rate.  In a Coriolis meter fluid is passed through a small vibrating flow tube causing a deflection of the flow tube proportional to the mass flow rate of material.  The basis of good flowmeter selection is a clear understanding of the requirements of the particular application. Measuring the flow of liquids and gases is a critical need in many industrial plants. In some operations, the ability to conduct accurate flow measurements is so important that it can make the difference between making a profit and taking a loss. In other cases, inaccurate flow measurements or failure to take measurements can cause serious (or even disastrous) results.

Important specifications to consider when looking for mass flow meters include mass flow rate range, operating pressure, fluid temperature range, and accuracy.  Mass flow meters measure flow rate in units of mass flow, for example, lbs/min.  The operating pressure is the maximum head pressure of the process media the meter can withstand.  The maximum temperature of the media that can be monitored is usually dependent on construction and liner materials.  Accuracy is measured in () %.  Pipe diameter is also important to consider, especially when specifying specific mounting options.  Mounting options for mass flow meters include insertion types, in-line flanged, in-line threaded, and in-line clamp.  Insertion flow meters are inserted perpendicular to flow path. They usually require a threaded hole in the process pipe or other means of access.  In-line flanged flow meters are inserted parallel to the flow path, usually inserted between two pieces of existing flanged process pipes.  In-line threaded flow meters are inserted parallel to the flow path, and threaded into two existing process pipes.  NPT is the most common thread type.  In-line clamp flow meters are inserted parallel to the flow path, and clamped between two existing process pipes.

Mass flow meters can have one of several output types including analog voltage, analog current, frequency or pulse, and switch.  Interface options for mass flow meters include serial and parallel interfaces. 

• Technical Reference - Bulk Densities
• Technical Reference - Chemical Resistance
• Technical Reference - Dielectric Constants

Pages: 1 - 3 of 196