Longer shelf life, less preservatives
The P/DV type D-tec® control valve uses hermetically sealed D-tec® stem diaphragms. These provide improved contamination protection against the atmosphere and thus ensure microbial stability of the product throughout the entire process. While the D-tec® valve line can be used in aseptic processes, GEA sees the application of the new control valve primarily for ultraclean applications. The control valves are selected for products that require an extended shelf life, with or without cooling, depending on the pH value, cold chain and storage characteristics. These products include iced tea, fruit juice, fruit yoghurt and ESL milk.
Pascal Bär, product manager for aseptic valves at GEA, adds: “Durability is important to the consumer, but not at any price. Today’s consumers are very sensitive to the topic of preservatives. Ultraclean processing is beneficial here because it helps to achieve the desired shelf life of a product with less preservatives. As part of a customized process chain, our new D-tec® P/DV valve control valve takes manufacturers this one step further.”
Special valve diaphragm connection increases pathogen barrier and service life
“The critical point between valve stem and stem diaphragm has an increased risk of pathogen introduction: Here, metal and plastic – two materials that react differently to temperature and pressure – come into contact. For this reason, we have designed a supporting ring that guides and counteracts the stem diaphragm during stroke movement. This approach is more effective than other options available on the market”, says Bär, explaining how the valve contributes to increased process and product safety.
In addition, this type of connection ensures that the membrane is subject to minimal mechanical stress during the switching process. With this approach, GEA has succeeded in making the stem diaphragm last longer as well as demonstrably keeping its temperature resistance and cleanability high. “Our main goal is to ensure system availability and economic viability for food and beverage producers. This is achieved by our new control valve, which combines functional flexibility and quality with manageable operating costs”, concludes Bär. Producers gain further operational safety through reliable leak detection. GEA’s valve experts have designed the entire construction to be easy to maintain in order to reduce system downtime during maintenance.
Modular construction enables process adaptation
The P/DV D-tec® control valve is part of the VARIVENT® modular principle, which is characterized by its variability for different requirements. This enables the valve to be configured according to the prevailing process conditions. It has an equal-percentage control cone characteristic and is available in the valve sizes DN40 up to DN100 and OD1.5” up to OD4”. Different KVS values are available for each valve size and different housing combinations can be implemented. The valve seat can be executed with a metallic stop as well as soft (V-Ring) and hard sealing – the latter with the new TEFASEP® gold material, which GEA recently introduced. In addition, D-tec® control valves are equipped by default with the proven GEA T.VIS® P-15 position controller.
