The requirements for hygienic and operational safety in the pharmaceutical, biotechnology and the food and beverage industries are continuously increasing. In order to fulfill the requirements and the associated customer requirements, GEMÜ has developed the PD design (plug diaphragm) to combine the advantages of diaphragm valves with regard to cleanability with the advantages of globe valves with regard to controllability.
Diaphragm valves can also be used to implement rough control applications, provided that the desired flow rates are large enough. However, if a fine batch is required or a large control range must be covered, diaphragm valves soon reach their limits. Globe valves with flow restrictors may be precise control valves, but they are anything but aseptic. Due to the so-called lift effect on the spindle, medium is transported into the gland packing and is not removed during plant cleaning, which can lead to the accumulation of dirt particles in this area and/or the multiplication of bacteria. In order to avoid this, bellows made from PTFE or stainless steel are often used as actuator seals.
But with this design solution too, medium can be deposited between the folds of the bellows.
With the newly developed GEMÜ PD design, the GEMÜ 567 BioStar aseptic control valve offers the option of precisely controlling the addition of small volumes in the range of 80 l/h to 4100 l/h in aseptic conditions in the pharmaceutical industry, the biotechnology industry, as well as the food and beverage industries. This opens up versatile aseptic applications, such as the highly precise dosing and automatic controlling of trace elements, additives, growth substances, flavourings or dyes, the preparation of biocultures, pressure control for WFI systems, aseptic tanks and fermenters.
Image courtesy of GEMÜ