Remote probe differential pressure transducer

摘要

A differential pressure transducer assembly for measuring flow in dirty and solids bearing fluids utilizes small barrier diaphragms located at the pressure taps of a flow measuring restriction. The barrier diaphragms are of minimum size and minimum thickness with a minimum volumetric compliance and are connected to a pressure receiving body by equal length capillaries of minimum i.d. A measuring transducer with a diaphragm having low volumetric displacement for measured differential pressures and having minimum volume diaphragm cavities is connected to the capillaries by equal and minimum volume cavities in the pressure receiving body. The pressure receiving body cavities on both the high pressure side and the low pressure side incorporate close tolerance inserts of material having a low thermal expansion coefficient when compared to that of the pressure receiving body, so that with increases in temperature the volumes of the cavities, which are minimized as much as possible, will increase just enough to match the increase in volume of the fill fluid which fills the cavities and capillaries.