Your country is not included? Please visit our global website Language Liquid Transfer With Low Pressure Pulsation Reduction of pressure waves by using multi-diaphragm pumps or pulsation dampers In the following blog post, you will learn more about possible KNF technologies enabling particularly gentle liquid transfer at low pressure pulsation. Stop-and-go traffic – or: Why pressure pulsation occurs For some applications or areas of use, the pressure pulsation can be significantly reduced by interconnecting several diaphragms in parallel or by using dampeners. Why pressure pulsation should be avoided As a leading manufacturer of diaphragm pumps, KNF has developed solutions for low pulsation liquid transfer to enable optimal application functionality: The FP pump series is based on two different operating principles. These are discussed in more detail below. Principle 1: Utilization of multi-diaphragm pump technology For many years, the portfolio of proven KNF diaphragm pumps has included both a single-headed and a double-headed version, the so-called boxer-style pump. With this, the connecting rod drives two 180° phase-shifted diaphragms simultaneously (analogous to a two-cylinder motor). While one diaphragm draws liquid from the suction line, the other diaphragm discharges it into the pressure line. This 180° phase-shifted mode of operation leads to pulsation-reduced transfer of the liquid. Figure 1 shows the instantaneous flow rate of multi-diaphragm pumps, such as double diaphragm pumps, compared to a single-headed pump. It impressively shows that flow rate peaks can be heavily reduced if several diaphragms are interconnected out-of-phase. From three diaphragms in use, peaks are reduced by a factor of 3. Due to this reduction of the maximum instantaneous flow rate, the pressure pulsation caused by the hydraulic resistances inside the system can be reduced significantly. Figure 1: Simplified representation of liquid discharge by diaphragm pumps without back pressure. The maximum instantaneous flow rate of a single-headed pump is three times larger than the nominal flow rate. The more diaphragms are interconnected in parallel, the smaller this superelevation becomes. Joining the two separate inlets and outlets of a double diaphragm pump together is relatively cost and time-consuming for customers, requires more space, and poses the risk of potential leakage at the respective fittings. This is why KNF took it one step further with its FP pump series and developed low pulsation pumps with up to five phase-shifted pump diaphragms. The individual flow volumes are joined inside the pumps. This way, customers strongly benefit from having only one connection on the suction as well as on the pressure side. This considerably simplifies handling for the customer, reduces the space required, and eliminates additional tube connections. Principle 2: Utilization of pulsation dampers and hydraulic accumulators On the pressure side, the pulsation damper absorbs part of the volume expelled by the pump. This can be easily seen from the upward moving damper diaphragm. If the pump diaphragm now starts sucking in again, the volume stored in the damper on the pressure side is released to the pressure line (damper diaphragm on the pressure side moves downward). Thus, a continuous volume flow inside the tube is also achieved on the pressure side. Thanks to the low volume flow fluctuations in the tubes, the pressure pulsation on the suction and pressure side is minimal due to the integrated dampers. This innovative design provides the customer with a low pulsation liquid diaphragm pump that, except for back pressure, operates virtually independently of the customer’s system. Depending on the pump type and operating point, the pulsation can be reduced by up to a factor of 20. Furthermore, additional interfaces are eliminated for the customer. This content requires your consent To view this content, please accept marketing cookies . This allows us to display videos and maps from external platforms. Advantages of pumps with low pressure pulsation To learn more about low pulsation liquid diaphragm pumps and how they may fit your application, contact our KNF experts. We can offer you a solution that can be specifically tailored to your needs. Related Blog Posts Contact Us Do you want to find out more about our customized pump solutions and service opportunities? Get in touch with our local sales representatives.