River water is an efficient and ecological coolant for industrial cooling distribution networks. However, the large volumes of water that must pass through the heat exchanger or chiller in the coolant production cycle require a low pressure drop and consistent flow levels. To accomplish these tasks, equipment must be selected to create the least possible resistance.
After evaluating several options, engineers chose the Stop-Silent check valve produced by Lasso Technik Inc., Basel, Switzerland, because it was able to achieve the required low pressure drop of 1.5 psi. The valve is constructed without movable mechanical parts and consists of only two components - a perforated stainless steel cone and a rubber membrane. When the valve is in the open position, the diaphragm deflects inward (figure 1, upper half). This movement allows passage of the coolant (in this case, river water) with minimal pressure loss. When the valve closes (figure 1, lower half), a backpressure condition allows the diaphragm to resume its relaxed position, covering all apertures in the cone and creating a tight shutoff.
As plants continue to look for ways to increase cooling efficiency and reduce maintenance requirements, new valve options will play an increasingly important role in helping to achieve these goals.PC
For more information about the cone-shaped valves, contact Great Western Supply Co., Houston, Texas, (713) 681-4786, e-mail Harry Boudreaux at email@example.com, or visit www.stopsilent.com.