Pressure Transducers

The Pressure Transducer is designed to directly measure the dynamic pressure of gasses, fluids and slurries flowing through pipes and conduits without the use of a probe or any other obstruction to the flow.  A short section of the line is replaced with a sensing component of the same cross-section that allows the free passage of the flow.  The sensing element of the transducer uses conventional strain gage technology applied directly to the wall of the conduit and can measure the dynamic fluid pressure acting against the wall.  The concept can be extended to measure flow rates and temperatures, providing a full flow process characterization. 

The transducer uses a double wall construction with a thin wall inner tube, isolated from the structural loads associated with the installation, and responsive only to the dynamic line pressure to provide a maximum signal sensitivity.  The outer shell provides for the safe support for all structural loads, while remaining insensitive to the dynamic line pressure.  The outer shell carries all loads associated with the attachment of the transducer to the line, the dead weight of the line and its contents, and any loading resulting from seismic loading, vibration and thermal expansion of the line.  The outer shell is designed to safely contain the flow, in the unlikely event of a structural failure of the sensing element.

The sensing element uses a Full Wheatstone Bridge, with electrically resistive strain gages applied to the exterior of the conduit, along with all temperature compensating circuit elements.  Gages are installed to be responsive to the dynamic line pressure at a single station along the conduit.   The Pressure Transducer directly measures the pressure of the contained flow with a high level of accuracy and dynamic response.  Furthermore, there is no need for an intermediate flexible bladder, hydraulic media or “T” connection to compromise the accuracy of the pressure reading, distort the time response, or introduce voids and disrupt the flow.
 
The Pressure Transducers are designed, manufactured and calibrated to each customer’s specifications.  A variety of materials are available for the sensing element, each selected for the particular application, e.g., corrosive liquids and gasses: sanitation products, foods, pharmaceuticals, and chemical processing; abrasive liquids: coal or dust slurries, cement/concrete slurries; and water/steam lines: utilities and power generation.  Two means of addressing the issues of wear resulting from the abrasion of hard particle slurry are available.  The sensing element can be constructed from a hardened material selected to resist the wear.  Alternatively, an energy absorbing liner has been designed and is available for installation for the bolted flange configuration.

The structural installation of the transducer can be accomplished with a variety of standard and specially designed attachments connecting the Outer Structural Shell to the flow line.  Bolted flanges, threaded fittings, frangible fittings
can be used as attachments.