Introduction When discussing automated cleaning systems, it is essential to distinguish between the rinse and foam functions. Nilfisk FOOD systems are engineered to deliver 200 Liters per minute (l/ min) of water for rinsing and, by default, 300 l/ min of foam. While it is not critical to utilize the full 200 l/min during the rinsing process, you must ensure you do not exceed this limit in any way. It is primarily a matter of managing the workload on the pump. In contrast, maintaining a flow rate as close as possible to 300 l/min is crucial when using the foam function. Insufficient flow can result in poor foam quality (either too thin or too thick), inade - quate foam delivery through the piping system, limited reach to the final nozzles, or pulsation within the system. It is important to note that of the 300 l/min foam output, only approximately 8% consists of water and cleaning chemicals; the remainder is air, which is introduced into the system to create foam. Valve Types: Ball Valves, Butterfly Valves, and Angle Seat Valves. The choice of valve is largely based on system designers preferences. At Nilfisk FOOD, we typically utilize ball valves with dual-action (DA) actuators. However, butterfly valves and an - gle seat valves are also suitable, each offering distinct advantages and limitations. There are no strict requirements regarding which type must be used. Ball valve with actuator. Optional configurations are available allowing for replacement of the injector block to adjust foam capacity to either 150 l/min or 450 l/min. However, foam output must be carefully bal- anced in accordance with the number of circuits and nozzles in operation. This topic is covered in more detail in the following section on system balancing. Driving Force: Water vs. Foam In rinse mode, water pressure serves as the system’s driving force. In foam mode, however, air pressure takes over this role. This is be - cause the water pressure passing through the injector is fully consumed in creating a vacuum that draws the cleaning chemicals into the sys- tem. 2 Balancing an Automated Cleaning System Effective system balancing is essential to ensure thorough cleaning performance and full surface coverage. In rinse mode, it is critical to ensure that the total flow requirement from all active nozzles and circuits does not exceed the system’s 200 l/ min capacity. Exceeding this limit may not only overstrain the pump but also result in insufficient water delivery to the nozzles furthest from the source, leading to inadequate cleaning cover- age. For foam, the standard injector output is 300 l/ min. To maintain optimal system performance, it is important to operate as close to this capac- ity as possible. Because foam output volume is 50% greater than that of rinse water (300 l/min vs. 200 l/min), the system should be divided into zones. This allows the operator to engage addi- tional nozzles during the foaming process to ac- commodate the increased volume. Drawing next page illustrates the appropriate configuration and zoning for both rinse and foam operations.
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