The measurement element composed by a concentric waving diaphragm, separates an upper housing called “of reference” which is empty, from a lower housing where the fluid pressure gets in. The upper housing is isolated by a bellows from the atmospheric pressure and it allows to transmit the bending diaphragm movement, under the fluid pressure action, to the pointer through a joint and a linkage. In order to be a suitable support for the diaphragm and to ensure a high instrument resistance to overpressure, the upper part of the reference housing is as rippled as the diaphragm. The instrument case is exposed to the atmospheric pressure therefore it is possible to install optional accessories inside or outside it.
The most popular type of diaphragm seals used in the industries.
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Diaphragm pressure gauges with flange connection
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Diaphragm pressure gauges with threaded connection
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