Category » Pumps

There were 22 articles found in this category:

1. Pump Curve Accuracy
   Introduction What are the attributes that make one pump selection software package superior to another? Aside from all the bells and whistles, the key to a superior pump selection program is the ability to accurately reproduce the manufacturers’ performance curves and to place the pumps th ...
2. Add a Fixed dp Component to the Most Hydraulically Remote Loop
   In the process of sizing a pump in PIPE-FLO, an over-controlled error may be encountered. Typically, this occurs when your pump is set to the "Size pump for" lineup setting and your flow rates are defined at all points in the system. In Figure 1 below, the supply pump is being sized for 800 g ...
3. Should the pump affinity rules be used to correct pump curve data when trimming impellers?
   Q. Should I use the pump affinity rules to correct my pump curve data when trimming the impeller? A. While the affinity rules can give a good approximation of pump performance for a given impeller trim, in some cases the error can be as high as 15 to 20%. Generally speaking, lower specific spee ...
4. Entering Pump Curves into PIPE-FLO or Flow of Fluids
   If the pump that you wish to model in PIPE-FLO is not available in one of the electronic pump catalogs, then the next best thing is to manually enter the pump curve data. This article will describe how to extract the appropriate data points from a pump manufacturer’s paper curve and enter ...
5. Modeling Positive Displacement Pumps
   Both PIPE-FLO and Flow of Fluids can be used to model positive displacement (PD) pumps. PD pumps are modeled using a combination of a fixed flow pump and a slip component. This article reviews the operation of PD pumps and demonstrates how to create a slip component using an example pump opera ...
6. Customizing Pump Catalogs
   This article is intended for Manufacturers who want to add custom elements to their Pump Curve Catalog. The attached document describes items that can be distributed with your pump curve catalog to customize the operation of PUMP-FLO and all OEM versions of the Pump Selection software. Engineere ...
7. Sizing Pumps in Series with PIPE-FLO or Flow of Fluids
   Some system designs require pumps to be operated in series, in which the discharge of one pump eventually leads to the suction of another. This is often done when pipeline and component losses in the system are substantial and it is not feasible (or at least not economical) to achieve the requir ...
8. Specifying a Preferred Operating Region in PUMP-FLO
   It’s easy to specify a preferred operating region on a curve using PUMP-FLO. The steps are primarily the same on both our web-based selection tool at www.pump-flo.com and when using the desktop PUMP-FLO software. Figure 1. From the Design Point Search screen, go to the Advanced Cri ...
9. Formats for Centrifugal Pump Curves
   When displaying pump curves in PIPE-FLO or PUMP-FLO, the amount of information displayed on the curve varies based on the way the pump performance data was entered. In this article we will discuss both of the ways in which pump performance data can be entered in PIPE-FLO using the PUMP-FLO selec ...
10. Reading a Pump Curve
    Pump Name and Speed The customary naming of a pump provides the discharge diameter, suction diameter, and maximum impeller diameter. In figure 1 we see the pump curve for a 4x6-13 pump. That means the pump discharge nozzle diameter is 4 inches, the pump suction nozzle diameter is 6 inches, and ...
11. Pump Curve Landmarks
    Pump manufacturers provide pump head curves showing the head, and efficiency as a function of the flow rate through the pump. This knowledge base article describes the various landmarks found on a pump curve, and describes why it is so important to operate any centrifugal pump within the manufa ...
12. NPSH & Pump Selection
    Pump Net Positive Suction Head (NPSH) is one of the most misunderstood aspects of pump hydraulics and can be one of the most damaging. Many technical articles and papers have been written on the subject, but little has been written on how this damage is done. The best material on the subject is ...
13. Change in Viscosity Correction Formulas
    For viscosity corrections, previous versions of PUMP-FLO used a set of equations that were derived from Figures 71 and 72 of the Hydraulic Institute Standards (14th edition, Hydraulic Institute, 1983). Two sets of equations were used: the equations based on Figure 71 were for pumps with a best ...
14. Using the Multiple Pump Calculator in PUMP-FLO
    Both the desktop and web-based PUMP-FLO software have an easy-to-use Multiple Pump Calculator to assist you in searching for pumps in parallel or series. To use it, start your search on the Design Point Search screen and simply click on the "Multiple Pump Calculator" button (see figure 1). ...
15. Modeling a Variable Speed Pump in PIPE-FLO
    When designing systems in which the system demand varies (for example, HVAC systems with varying loads throughout the day or year), variable speed pumps may be an effective cost savings option. In these systems, the pump speed can be adjusted to meet the varying demands of the system. Figure ...
16. Process Fluid Pump Curves
    The procedure used to specify "Process fluid" pump data has changed for PIPE-FLO Professional and Flow of Fluids version 2007. In previous versions, if a user had pump curve data which had already been corrected for the viscosity of a particular process fluid, the user would select the Process ...
17. Modeling and Troubleshooting Fixed Flow Pumps
    Instead of entering performance curve data, you can also specify a fixed flow rate and have PIPE-FLO calculate the total dynamic head required for the pump. When troubleshooting fixed flow pump installations, it is helpful to know how PIPE-FLO internally models them. A schematic of how PIPE-FL ...
18. Troubleshooting Pump and Component Models
    When pump or component data is entered, PIPE-FLO generates a "best fit" equation to model the device. If the curve has abrupt changes in its slope, this method may result in an inaccurate model. To more accurately model these types of curves, the data can be adjusted to give a better fit over th ...
19. Modeling Submersible Pumps
    Submersible pumps are placed directly into tanks and sumps. As a result, the pump suction is located directly in the tank and there are no connecting pipelines. The PIPE-FLO program requires a pump to be connected to both a suction and discharge pipeline. This Knowledge Base article describ ...
20. Modeling a Degraded Pump
    Often a piping system needs to be evaluated with a new pump in operation, and then evaluate after the pump performance has degraded. Using the approach outlined in this article you will be able to evaluate the piping system with both the new pump curve and the degraded pump curve without havi ...