Daisy Brands, Garland, Texas, makes sour cream known for a recipe that does not use additives, preservatives or artificial growth hormones. At a plant recently opened in Casa Grande, Ariz., the technology of the Danfoss Flexline motor-control valves and control stations provides close temperature control to help maintain the quality of the sour cream.
Tom Cooper, president of Refrigeration Concepts Inc. (RCI), Comstock Park, Mich., the company that built the production line, explained that Daisy has specific requirements for its proprietary production process. As such, precise temperature control is a benchmark that Daisy insists on.
To meet these temperature requirements, Cooper installed the plant’s ammonia refrigeration system to produce chilled water to cool vats and silos, and to supply evaporator coils in the storage area. The circulation of ammonia refrigerant in the system is controlled by various valves assembled together in valve trains or stations. The valves open and close to regulate the flow of refrigerant from compressors to heat exchangers to evaporator coils to condensers.
A typical valve train is assembled from four or five components. Using the traditional method, each valve would have to be ordered, unpacked, assembled and welded into piping, and the finished valve train would then be shipped to the job. Because each valve requires two welds, that could involve up to 10 welds or more per valve train.
The Casa Grande project involved about 25 valve trains, which would have involved up to 250 welds had typical valve trains been used. Flexline allows for fabrication of valve trains from start to finish. An ICF station consists of a single valve body with multiple port openings. Individual valves can be specified and installed at the factory to build the required configuration. This allows replacement of a string of valves with just one valve station, allowing for faster installation.
The multi-ported ICF valve train is about a foot long. The body is a modular design that accepts ready-made inserts that are simply pushed into the precision-machined opening to accomplish the desired function. Then, a separate top cover is added for protection. Function modules that can be mounted on an ICF body include: stop valves, strainers, solenoid valves, check valves, combination stop/check valves and motorized or hand expansion valves.
For the Daisy Brands project, the ICF valve train was configured with Danfoss ICM motorized valves, which have a valve body, a combined function module/top cover and an ICAD actuator. Only two welds were needed on each valve train, which eliminated the need for flanges and gaskets, reducing the probability of leakage. The IFC valve train is also more compact, about one foot instead of four. This saved plant space and reduced the amount of refrigerant required for the line. Finally, it offered adaptability, with a multi-ported body that is able to accept over-stop valves and line sensors.
