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There were 28 articles found in this category:

1. How Not to Save Energy by Installing a High Efficiency Motor
   As Seen in the June 2011 Issue of Plant Engineering Magazine Introduction The Energy Independence and Security Act of 2007 (EISA), which mandates that all new motors sold in the United States must meet a minimum motor efficiency, went into effect on December 19, 2010. The law doesn’t app ...
2. 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 ...
3. Value of the System Resistance Curve (Part 2)
   System Operation with a System Resistance Curve Introduction This article is a continuation of the newsletter article dealing with the System Resistance Curve. As discussed in the last installment we saw how a system curve was created by calculating the head loss for each pipeline in the system ...
4. Value of the System Resistance Curve (Part 3)
   This is the last installment of the three part series on the System Resistance Curve. In this section we will explore the difficulties of generating a system resistance for piping system with multiple destinations. We will also see how this type of system can be better understood using a Pump Sy ...
5. Time Simulation with PIPE-FLO
   It is often necessary to see how a piping system operates over time. For example, as a tank is pumped down, the static head increases resulting in a smaller flow rate through the pump. This reduction in flow rate causes the tank to take longer to pump down. This type of calculation is called an ...
6. Using Overtime In Ship Deballasting Operation
   Background A naval architect and PIPE-FLO® user recently called for technical support on a unique piping system problem he was trying to solve. He was working with a shipyard and was tasked with determining a method to pump out six ballast tanks on a ship while the ship's cargo was being loa ...
7. What is suction specific speed and how can it be used in centrifugal pump selection?
   Q. What is suction specific speed and how can it be used in centrifugal pump selection? A. Suction specific speed is an index that describes the characteristics of the suction side of the impeller. It is calculated using the NPSHr in feet, speed (N) in rpm, and flow rate (Q) in gpm at the pump& ...
8. 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 ...
9. Value of the System Resistance Curve (Part 1)
   Introduction This knowledge base article describes the value of a system resistance curve in understanding of how the various elements in a fluid piping system operate together. System resistance curves can be used to graphically determine flows and pressures in process systems where there is ty ...
10. How Pressure Independent Control Valves Work
    Introduction The Pressure Independent Control Valve (PICV) technology was brought to market 18 years ago. This technology has now matured and is accepted as a proven application for optimizing hydronic system delta T, enhancing system performance and reducing energy cost. A high quality, indus ...
11. How Can a Pipeline Have Positive Differential Pressure
    Q. I’ve noticed that some of my pipelines have positive differential pressures being calculated. How can a pipeline have a positive dP? A. Customers often wonder how a pipeline can have a positive dP or how PIPE-FLO can calculate flow going from a lower pressure to a higher pressure. Th ...
12. Pump Sizing
    Selecting the proper pump is the most important step in the development of a piping system. The pump must be sized to handle the desired flow rate at the required pressure from the supply to the destination. In order to size a pump, you must take into account the change in elevation and pressur ...
13. How to Model a Pressure Independent Control Valve in PIPE-FLO
    Introduction The use of Pressure Independent Control Valves (PICVs) has gained wide acceptance in many HVAC chilled and heating water applications. Quality PICVs with high turndown provide accurate control of flow rate regardless of the differential pressure fluctuations across the valve. This a ...
14. VFD Pumps Can Cut Energy Costs but Static Head Reduces Savings
    The pump affinity rules describe how pump flow rate (Q), total developed head (H), and power consumption (P) change with a change of impeller speed (N) for a centrifugal pump or fan, and are shown in Equation 1 below. Since the flow rate changes in direct proportion to the speed, and head change ...
15. Minimizing Pumping Costs
    In this example we will see how selecting the proper design point can improve a pump's operation and minimize pumping cost. Before a pump is selected for a given application, a series of calculations must be performed to determine the system's static head and pipeline head loss for a given desi ...
16. Balancing a System
    Piping systems providing heat transfer fluid to a variety of loads can present their own special problems. Since there are multiple paths for the fluid to travel, the system naturally balances so the pressure drop around each loop is equal. It is highly unlikely that when all of the valves are ...
17. Correcting Problem Control Valves
    Piping systems are a collection of pumps, control valves, components, tanks and vessels. Often even the simplest piping system can present a large problem when it is not operating properly. In this example, we have a single pump circuit that pumps from a storage tank to a pressurized tank. A he ...
18. Method of Solutions Version 2009
    These method of solution files are provided for users who want detailed documentation on the 2009 version of PIPE-FLO software and its modules. PIPE-FLO software incorporates industry standard calculation methods to insure consistent program operation and accurate results. Detailed documentati ...
19. Method of Solutions Version 2007
    These method of solution files are provided for users who want detailed documentation on the 2007 version of PIPE-FLO software and its modules. PIPE-FLO software incorporates industry standard calculation methods to insure consistent program operation and accurate results. Detailed documentati ...
20. Method of Solutions Version 2005
    These method of solution files are provided for users who want detailed documentation on the 2005 version of PIPE-FLO software and its modules. PIPE-FLO software incorporates industry standard calculation methods to insure consistent program operation and accurate results. Detailed documentati ...