Are pressure gauges ideal for pharmaceutical processes? Yes, if they’re available in a version with flush diaphragm element. There are two advantages of a mechanical pressure measurement with this kind of instrument: Diaphragm pressure gauges measure ?dry? and thus reduce the threat of contamination. In addition, they provide a reliable measurement, even in critical situations, because of their extremely robust diaphragm element and the high overload safety.
In numerous pharmaceutical processes, diaphragm seal systems are accustomed to control the procedure pressure, also in combination with a pressure gauge. A diaphragm seal separates the measuring instrument from the procedure and therefore protects it against influences. Its sensitive diaphragm for the transmission of pressure through liquid is relatively thin, as a result of accuracy of measurement. When compared to diaphragm as the pressure sensing part of a diaphragm pressure gauge, it is therefore more susceptible, both to unpredictable process conditions (pressure peaks, overload) also to mechanical influences. If the diaphragm is damaged, system fill fluid can enter the procedure.
The mechanism of a PG43SA pressure gauge with flush diaphragm element
No contamination
Pressure gauges with a flush diaphragm element eliminate such contamination since they operate without liquid. Their robust diaphragm element transmits the pressure, via a link, right to the movement. It is two to five times as thick as a conventional diaphragm seal diaphragm. The diaphragm element is therefore effectively protected against unexpected physical effects. In addition, it can absorb a high overload ? with WIKA instruments that is around five times the nominal pressure.
Furthermore, pressure gauges for pharmaceutical processes must meet the stringent requirements for sanitary applications in every respect. It has been implemented by WIKA in its PG43SA series. For pressure gauge octa , a diaphragm element of only 35 mm in diameter was developed. Because of its special wave contour and the thickness of its material, the diaphragm includes a measuring quality much like the diaphragm element of an average process instrument ? though this would become more than twice the size for a comparable pressure range.
Easily cleanable
All instruments of the PG43SA series comply with the rules of hygienic design, the 3-A Sanitary Standard and so are certified to EHEDG. They are suitable for CIP/SIP processes and are optionally completely autoclavable.
Two of the models (PG43SA-S and PG43SA-D) are pressure gauges with a radial process connection. For the model PG43SA-C, however, the procedure connection is integrated into the case. This patent-pending design enables space-saving and for that reason flexible installation.
Integrated safety system
The model PG43SA-D has been tuned to match particularly critical processes. The pressure gauge includes a patent-pending integrated safety system. It offers a second protective barrier and diaphragm element monitoring. Should an unexpected diaphragm rupture occur, the procedure and measuring instrument remain securely separated. The medium cannot escape in to the environment and likewise, nothing contaminating will get its way in to the process. Any instance of damage becomes known immediately: The diaphragm element monitoring reports it directly with a red indicator on the dial.
Designed as pressure gauges for pharmaceutical processes (f. l. t. r.): Model PG43SA-S (standard), model PG43SA-C (process connection in the event) and model PG43SA-D (with additional safety system).
Note
For detailed information about the three diaphragm pressure gauges PG43SA-S, PG43SA-D and PG43SA-C, please go to the WIKA website. A concise overview is supplied by the flyer for this instrument family.
For further information please watch the following video about the diaphragm pressure gauges of the PG43SA series: