Pressure Isolation
A flexible thin-walled barrier separates process fluids from internal sensing elements to prevent corrosion or physical damage. The isolation diaphragm transmits force through a fill fluid to the internal transducer while maintaining a hermetic seal against the medium. Manufacturing tolerances remain tight across the surface area to ensure the mechanical spring rate introduces minimal error into the total measurement uncertainty.
Material Compatibility
Chemical resistance dictates the selection of alloys or coatings that interface with the monitored process. Stainless steel grades provide baseline performance for neutral liquids, whereas tantalum or gold plating prevents degradation in acidic or reactive streams. Proper installation requires alignment to avoid localized stress that causes premature fatigue.
Temperature Correction
Volumetric expansion of the internal fill fluid shifts the zero point when process or ambient heat fluctuates. These thermal effects change the tension applied to the membrane, which alters the output signal relative to the calibration point. Compensatory algorithms in the transmitter circuitry account for this drift based on secondary temperature sensor inputs.
Installation Accuracy
Proper mounting orientation eliminates static head errors caused by the weight of the fill fluid pressing against the sensing face. Vertical or horizontal placement shifts the baseline voltage, a condition corrected during the initial field zeroing procedure. Calibration at the operating pressure verifies the stability of the entire assembly over the expected service life.
