Autofrettage in pressure sensors ensures zero-point stability

In the manufacturing operation of pressure sensors, autofrettage denotes the procedure of active ?overload? by subjecting the pressure sensor selectively once or many times to a pressure above the nominal pressure range. This process is applied, to experience maximum stability, specifically of the zero point, in later operation. Assuming the right design of the sensor, autofrettage enables a long time of trouble-free operation of the sensors even at high load cycles achieving the specified overload range, without resulting in zero-point shift or similar effects.
In autofrettage, certain local regions of the sensor, where through the selective overload the yield point of the sensor material is locally exceeded, become plasticised, producing a permanent change of the instrumentation characteristics. This selective effect on the structural conditions through autofrettage is an integral area of the development of the sensor and of the associated manufacturing process. Which pressure the sensor is subjected to and how often, must be determined individually for each sensor design through an elaborate FEM simulation and extensive test series.
Caution ? no experiments of your! However, it must not be figured every sensor will automatically benefit from subjecting it to autofrettage. Autofrettage can only be used for ductile materials, but for no reason for brittle ones. Conditioning should be scheduled and completed very selectively and with great care during the production stages. เกจวัดแรงดันแก๊สอาร์กอน -considered ?overpressurising? of pressure sensors by laymen who like experimenting will not only damage the sensor permanently, but additionally result in dangerous preliminary damage and subsequently possibly in accidents caused by fatigue and bursting of the sensor. In this way, a noticable difference in instrumentation will only be achieved, if, by hit or miss.

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