The purpose of the system resistance curve is to show where the pump operates on its pump curve. One creates a system curve is by calculating the head loss for various flow rates through the system piping and superimposing the system curve on the pump curve. The intersection of the pump and system curves is the balanced flow rate through the pump.

This works well for simple systems with one supply, one pump, and one destination, but the system curve becomes very difficult to understand with multiple sources for pumps, multiple pumps, and multiple paths and destination points. That is where a program like PIPE-FLO comes in.

Rather that graphically creating a complex system curve by hand, PIPE-FLO performs a full numerical analysis and calculates the balanced flow rate through the pump. In addition, since PIPE-FLO has the pump curve data it shows the flow rate through the pump you can easily see where the pump runs on its curve.  

Since PIPE-FLO has detailed operating information about the pump, the program provides you indication when a pump is running outside a range of operation, when the pumps Net Positive Suction Head requirements are not being met, or when the pump is running below the manufacturers minimum flow requirement.

Engineered Software will be conducting two FLO-MASTER seminars in:

• Chicago, IL on October 19 & 20, 2004

• Las Vegas, NV on November 9 & 10, 2004

By attending one of our two-day FLO-MASTER seminars, you will:

• See how to get the most from PIPE-FLO on your next piping projects

• Learn how to build a piping system model quickly using pipe specifications and PIPE-FLO’s various copy commands

• Discover how PIPE-FLO can provide you with a clear picture of any fluid piping system

To find out more about the upcoming FLO-MASTER seminars, call your Engineered Software Territory Rep, toll free at (800) 786-8545, or direct your browser to www.eng-software.com/products/flomaster.htm. These hands-on seminars qualify for 15 Professional Development Hours needed to fulfill Professional Engineers’ continuing education requirements in many states.

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A pump curve describes how a centrifugal pump will operate. The system pressure at the pump's discharge fixes the flow rate through the pump. By knowing the flow rate and desired discharge pressure you can select a pump by looking at the pump curves.

The manufacturers pump curve contains additional information regarding the allowable operating range of flows through the pump, along with the minimum flow rate allowed through the pump. For more information on centrifugal pumps curves please click on the Knowledge Base article "Pump Curve Landmarks" http://www.eng-software.com/kb/item.asp?ID=1387

The minimum flow and allowable operating range are limits placed on the pump by the manufacturer. If these limits are exceeded the pumps operation and life is degraded.

The electronic pump catalogs, supplied by the pump manufacturers (http://www.eng-software.com/pml), are critically reviewed by each manufacturers and contain their limits. By loading the pump performance data from the manufacturers supplied electronic pump catalog PIPE-FLO is aware of all the manufacturers limits. If the operation of the pump falls outside the manufacturers supplied limits PIPE-FLO provides you with immediate notification of the problem.

Using PIPE-FLO and the manufacturers supplied electronic pump catalog, you can make sure your total piping system is operating properly.

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Recently the Hydraulics Institute developed HI Standard 9.6.3 "Allowable Operating Region" describing the importance of operating a pump within the manufacturer’s allowable operating region. The standard also introduces the preferred operating region.

In PIPE-FLO version 8 we incorporated a preferred operating region that can be established for each pump. When the pump is running outside of the preferred operating region PIPE-FLO notifies you of the problem.

PUMP TRAINING CLASSES AVAILABLE

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Our support desk continually gets the question "Can I model a pump that is not in a manufacturers catalog?" The answer is yes. There are two ways you can manually insert a pump into a PIPE-FLO model.

The easiest way is to enter the operating data in the pump dialog box. Here you can insert up to 10 operation points of flow and head for the pump. You can also enter the pump efficiency and NPSH required as well. If this information is entered PIPE-FLO can let you know if the pumps NPSH requirements are not being met. If you enter the pump data based on a water performance, and enter the efficiency PIPE-FLO can automatically adjust the pump curve when viscous fluid is being pumped.

If you use the same pump in multiple applications within your plant, you may want to add the pump to your own pump list. When a pump is entered into the pump list, you can evaluate the pump and insert the pump performance data into your PIPE-FLO system without having to re-enter the data.

Both of these methods are great ways to enter pumps from manufacturers without electronic pump catalogs. So as you can see PIPE-FLO can model centrifugal pumps from any manufacturer.

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Engineered Software will be exhibiting the PIPE-FLO program at the Water Environment Federation annual meeting WEFTEC in New Orleans, LA from October 2-6, 2004. We’ll be demonstrating PIPE-FLO Professional 2004 showing how the software is helping engineering firms design pressurized waste collection piping systems and waste treatment plants. If you plan on attending the WEFTEC exposition please stop by booth 5747.

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HOW TO USE THIS MAILING LIST