Design and applications

The DDM-EM measuring orifice measures and monitors the flow of gases and liquids.

The device works according to the principle of differential pressure. A differential pressure exists on the orifice, which is proportional to the square of the volume flow through the pipeline. The user mounts the orifice between flanges or with Rp pipe unions into the conduit. The unimpeded, straight tube length has to be 6 DN before and 4 DN behind the mounting position.

A tough and insensitive sensing diaphragm is embedded in the EM-transmitter housing. By the differential pressure a spring force occurs at the measuring diaphragm. The resulting displacement is transmitted to the core of an inductive displacement transducer via an axial rod. The built-in electronics evaluates this deflection and transforms them into direct display, limit value switches and output signal.