It can take up to three years to turn bacteria, viruses or cell cultures into a vaccine. Since vaccines are injected directly into the body, safety and purity have the highest priority in production. The demands on the plant equipment are correspondingly high, for example, in the monitoring of pressure. The PG43SA series of diaphragm pressure gauges from WIKA are tailored to this.
Three instrument models to choose from
The hygienic instruments with flush, welded diaphragm elements are suitable for pressure monitoring in all areas of vaccine production. This applies, not only to the “upstream” and “downstream” stations, but also to the support processes.
There are three 3A and EHEDG-certified models to choose from:
- PG43SA-D with integrated diaphragm element monitoring
- PG43SA-C particularly compact with back mount process connection
Which variant a user chooses, and at which point in the process, depends on their safety requirements and the installation conditions – although the model PG43SA-S already meets a large part of the requirements for pressure monitoring.
Critical situation at a glance
The further the vaccine production progresses, the more valuable the product becomes. During the “downstream” filtration processes, the future active ingredient is increasingly purified. Here, pressure monitoring provides the decisive information as to whether the filters are still working correctly or are clogging up and need to be replaced. The model PG43SA-S with red limit value marking, for example, enables a critical situation to be detected, unmistakably, at a glance.
That the compact nature of the instruments can also be important in this task is illustrated by a filtration system at a vaccine manufacturer in China: in this case, a peristaltic pump conveys the active ingredient to the capsule filter via a hose. The challenge of the very cramped available space meant a small measuring instrument was required, and the model PG43SA-C met this.
The instrument was able to be easily attached to the hose before and after the filter due to its process connection being integrated into the case – a patented design. This measuring solution shows the operator whether the pump and filter are working normally. The PC43SA-C offers a good plan view for this. It is therefore also suitable for pressure monitoring in vertical pipelines.
The models in the PG43SA series, like all diaphragm pressure gauges, as a result of their mechanical principle, always reliably indicate the process pressure. They measure with high overload safety and independently of electrical energy. This meets the safety requirements, especially when transporting the intermediate products and the finished vaccine. These are transported in mobile tanks from the bioreactor via chromatograph and filtration systems through to filling into ampoules.
Multiple tasks in one application
When monitoring the pressure at the tanks, the PG43SA instruments fulfil several tasks: During transport, it is important to check whether the pressure remains constant. This is also a leak test: a falling pressure may be due to a leaking valve or a damaged seal. After emptying the tank at the transfer point, one look at the display can determine whether there is still pressure in the tank or whether it can be opened without danger. The same applies to pressure monitoring during tank cleaning and the pressure test before refilling.
In tank applications, in addition to the measurement quality described, another advantage of diaphragm pressure gauges comes to the fore: the instruments work with a “dry” measuring cell. This eliminates the risk of product contamination by a system fill fluid, as is the case with conventional diaphragm seal systems. In this way, they prevent potential damage that could amount to millions.
Further risk minimisation
In these and similar sensitive processes, the model PG43SA-D helps to further minimise risks to the vaccine. The instrument has an integrated diaphragm element monitor with red/white indicator. In the unlikely event that the very robust measuring element should break due to extreme process conditions or rough mechanical influences, the patented monitoring function immediately reports the damage via a “red” indicator. A second barrier in the instrument maintains the separation of process and environment.
Suitable for CIP/SIP and autoclavable
Process reliability in vaccine production includes residue-free cleaning of the equipment after each batch. Due to their hygienic design, the PG43SA diaphragm pressure gauges are suitable for CIP/SIP cleaning processes and are all autoclavable.
You can find an overview and technical details of the PG43SA series hygienic diaphragm pressure gauges on the WIKA website or in our flyer: “Safe and reliable: Pressure displays in hygienic design”. If you have any questions, your contact will gladly help you.
The following video also informs you about the PG43SA instruments: