Freeze drying is a method for carefully extracting moisture from products like food or serums. Such products are sensitive to temperature and care has to be taken in order to protect their internal structure. Freezing is followed by an accurately controlled pressure decrease, which leads to sublimation of the microscopic ice crystals.
Losses of expensive product lots must be avoided and process run at reasonable cost. This is why the demands on the required vacuum gauges regarding repeatability and reliability are extremely high.
The VSP63MV Pirani is protected against vapor condensation by a stainless steel shield. Its metal sealed sensor with long-life helix filament and the stainless steel flange make the gauge especially robust. The results are an improved reliability of the process and a decrease of maintenance costs.