Are pressure gauges suitable for pharmaceutical processes? Yes, if they are available in a version with flush diaphragm element. There are two advantages for a mechanical pressure measurement with this particular kind of instrument: Diaphragm pressure gauges measure ?dry? and therefore reduce the threat of contamination. In addition, they offer a reliable measurement, even yet in critical situations, because of their extremely robust diaphragm element and the high overload safety.
In various pharmaceutical processes, diaphragm seal systems are accustomed to control the process pressure, also in conjunction with a pressure gauge. A diaphragm seal separates the measuring instrument from the process and thus protects it against influences. Its sensitive diaphragm for the transmission of pressure through liquid is relatively thin, as a result of accuracy of measurement. Compared to the diaphragm as the pressure sensing component 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 process.
The mechanism of a PG43SA pressure gauge with flush diaphragm element
Pressure gauges with a flush diaphragm element eliminate such contamination given that they operate without liquid. Their robust diaphragm element transmits the pressure, via a link, right to the movement. It really is two to five times as thick as the standard diaphragm seal diaphragm. The diaphragm element is therefore effectively protected against unexpected physical effects. In addition, it can absorb a higher 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 all respects. This has been implemented by WIKA in its PG43SA series. Because of their instruments, a diaphragm part of only 35 mm in diameter originated. Due to its special wave contour and the thickness of its material, the diaphragm includes a measuring quality much like the diaphragm component of a typical process instrument ? though this might be more than twice the size for a comparable pressure range.
pressure gauge 10 bar of the PG43SA series comply with the guidelines of hygienic design, the 3-A Sanitary Standard and so are certified to EHEDG. They’re 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 has a patent-pending integrated safety system. It offers a second protective barrier and diaphragm element monitoring. Should an unexpected diaphragm rupture occur, the process and measuring instrument remain securely separated. The medium cannot escape into the environment basically, nothing contaminating will get its way into the process. Any instance of damage becomes known immediately: The diaphragm element monitoring reports it directly via 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).
For detailed information regarding the three diaphragm pressure gauges PG43SA-S, PG43SA-D and PG43SA-C, please go to the WIKA website. A concise overview is provided by the flyer for this instrument family.
For more info please watch the next video concerning the diaphragm pressure gauges of the PG43SA series: