ABSTRACT
Typically diaphragms, bellows, or Bourdon tubes are most commonly used; the choice depending primarily on the amount of elastic deflection required for the data presentation element. The diaphragm is not only the simplest to construct of all the elastic members but is the best sensing element that can be used in a high-Vibration environment. In designing diaphragms the designer is interested not only in its deflection for a given pressure but also in a linear deflection-pressure relationship. The relationship between applied load and deflection of a diaphragm may be represented in tabular or graphical forms. Since diaphragms are elastic links, the spring rate and its reciprocal, the sensitivity, are normally used in evaluating their Performance characteristics. It is common, where high sensitivity is desired, to mount diaphragms in series as is the case with bellows and capsules. In some rare applications, diaphragm elements may be mounted in parallel.
