About Differential Pressure (DP) Flow Measurement | Emerson US (2024)

Three essential elements are required to engineer a differential pressure flow meter. The primary element creates a pressure drop across the flow meter by introducing a restriction in the pipe, and this engineered restriction enables Bernoulli’s equation to be used for a flow rate calculation. The pressure drop is measured by a secondary element, a differential pressure transmitter, while tertiary elements consist of everything else within the system, such as impulse piping and connectors.

Pressure primary elements offer many designs and options for diverse line sizes and flow rates. Options include standard and conditioning orifice plates, averaging pitot tubes, and wedges. Each option features benefits, such as tighter process control, several mounting configurations, high accuracy, easy installation, low maintenance cost, reduced permanent pressure loss, and integral temperature sensor options for reduced process penetrations.

DP Flow is proportional to the square root of differential pressure, making pressure a critical component of DP Flow calculations. Other factors that influence the mass flow include: density, viscosity, temperature, pipe diameter and fluid type. In many industrial processes, numerous measurement and control devices are used to ensure accurate liquid, gas and steam flow rates for increased safety, productivity and cost-efficiency.

For best-in-class performance, MultiVariable™ transmitters measure static pressure, differential pressure and temperature and can be engineered to calculate flow. Flow meters can provide process variable outputs as well as calculated real-time mass, volumetric or energy flow. Calculated flow output delivers accurate, reliable information quickly for improved process performance.

DP Flow measurement can be utilized to optimize many aspects of a process, including product consistency, custody transfer, production efficiency and safety applications.Rosemount DP flow measurement solutions are versatile, easy to install and troubleshoot. Devices are suitable for use in a wide range of fluids including corrosive liquids, slurries, saturated or superheated steam, gas and many other process applications.

Wireless technology enables flowmeters to quickly obtain additional critical process information, even in adverse conditions. This technology helps extend asset life, increase process unit efficiency, minimize maintenance, and meet safety and environmental goals by delivering timely information. In addition, fully integrated wireless flowmeters reduce installation costs and provide process optimization.