Pump Ed 101
Understanding Pumps, Motors, and Their Controls
Joe Evans, Ph.D   (About the Author)         Pump Ed 101 Seminars & Training         About the Tutorials

Click on the categories below to view the available tutorials



                    Basic Hydraulics - Centrifugal Pumps                Pump Evaluation, Selection & Testing Tools

                    Basic Hydraulics - Displacement Pumps              Electricity, Motors, & Controls

                    Other Pump Topics                                    The Puzzler

                    Sewage & Wastewater                                Pumps & Systems Magazine Columns

                    Variable Speed Pumping                               Other Educational Sites

                                                                            
VAST  (Various And Sundry Things)

Some of my older papers have an invalid email address. Contact me at joeeevans@gmail.com





































































Basic Hydraul
ics - Centrifugal Pumps

Click on a topic below for a brief description of its contents.

A Brief Introduction to Centrifugal Pumps

Centrifugal Farce & Affinity

Centrifugal Pump Dynamics

Liquid Friction - The Tarantino Effect

Specific Gravity & Viscosity - Parts 1 & 2

Net Positive Suction Head - NPSHa & NPSHr

Centrifugal Pump Efficiency

Preservation of Efficiency - Affinity Revisited



Cavitation - A Largely Misunderstood Phenomenon

When Bubbles Don't Burst - Why Cavitation is Damaging

Waterhammer - Its All About Conserving Energy

Waterhammer - Parts 1 & 2

Radial Thrust Calculator

Suction Specific Speed & Suction Energy Calculators


Wire to Water Energy Calculator


Centrifugal Pump Operation at Off Design Conditions - Karassik


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Waterhammer - Parts 1 & 2

This waterhammer tutorial looks at the subject from a different perspective than does my earlier one.  Part 1 covers what? & why? while Part 2 looks the the causes and variables.  See my August & September 2008 Pumps & Systems magazine articles for additional reading.

Download Part 1

Download Part 2

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When Bubbles Don't Burst - Why Cavitation is Damaging

This tutorial takes a look at cavitation from a different perspective.  It expands upon my original turoral "Cavitation - A Largely Misunderstood Phenomenon.

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Preservation of Efficiency - Affinity Revisited

In "Centrifugal Farce & Affinity" we took a look at the affinity laws and showed how the predict pump performance when its speed changes or its impeller is trimmed.  This tutorial goes a step further and describes the effect of these changes on pump efficiency.

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Net Positive Suction Head - NPSHa & NPSHr

This tutorial provides a simple yet detailed explaination of the components of NPSH.  It also discusses their relationship to cavitation in a centrifugal pump.  See my May 2008 Pumps & Systems magazine article for additional reading.

Download

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Specific Gravity & Viscosity - Parts 1 & 2

Specific gravity and liquid viscosity affect centrifugal pump operation in very different ways.  This two part tutorial discusses the impact of each.  Part 1 covers SG while Part 2 looks at Viscosity.  See my March & April 2009 Pumps & Systems magazine articles for additional reading.

Download Part 1

Download Part 2

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Liquid Friction - The Tarantino Effect

The physics of liquid friction is still pretty sketchy.  Unlike solid friction, velocity and surface area are major considerations.  This tutorial compares these two forms of friction and goes into some detail about each.

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Centrifugal Farce & Affinity

Centrifugal force is a farce!  It is all about the velocity added by a pump's impeller.  This tutorial dispells this myth and explains the relationship of velocity to the three affinity laws.

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Energy Calculators


Wire to Water Energy Calculator

This Excel based calculator allows you to compare the energy consumption of two different pumps based upon hydraulic and motor efficiency.  It computes annual operating costs for both and the payback period for the more efficient system.  See my March 2001 Pumps & Systems magazine article for additional information.

Download

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System Energy Calculator

This Excel based calculator allows you to compare the energy consumption of two pumps operating under different system conditions.  It computes annual operating costs for both and the payback period for the more efficient system.  The example included is for a pump that is pumping 600 GPM through 600 feet of 6" and 8" steel pipe.

Download

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Off BEP Energy Calculator

See my January 2012 Pumps & Systems article for information on this calculator.

Download

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Basic Hydraulics - Displacement Pumps


Click on a topic below for a brief description of its contents.

Positive Displacement Pumps - Part 1 Reciprocating Pumps

Positive Displacement Pumps - Part 2 Rotary Pumps

Viking Pump Company - PD Pump White Papers


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Other Pump Topics


Click on a topic below for a brief description of its contents.

Constant Pressure Booster Systems

The Self Priming Pump

How Curve Shape Can Influence Pump Selection


Siphons & the Siphon Effect - That Sucking Sound

Pascal's Principle - Paradox Lost

Parallel Pumping - Parts 1 & 2

Two Steps to Longer Pump Life - Parts 1 & 2


Centrifugal Pump Operation at Off Design Conditions - Igor Karassik


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Centrifugal Pump Operation at Off Design Conditions - Parts 1 - 3

In the mid eighties, Igor Karassik wrote a three part series that described the problems associated with off BEP operation.  Part 1 explores radial thrust and temperature rise while Part 2 looks at internal recirculation and air binding.  Part 3 discusses discharge recirculation and discharge bypasses.  All are written in a very understandable manner which is the goal of Pump Ed 101.  These are scanned files and the resolution is not very good.  In your Acrobat tool bar, increase the page size to 130% for an easier read.

Download Part 1

Download Part 2

Download Part 3

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Two Steps to Longer Pump Life - Parts 1 & 2


This tutorial explores the two most important preventive maintenance steps that influence pump and motor life.  Part 1 looks at off BEP operation and outlines how to determine the "as built" operating point.  Part 2 investigates current unbalance and the corrective measures that should be taken.

Download Part 1

Download Part 2

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Parallel Pumping - Parts 1 & 2


Sometimes the flow and head of two pumps operating in paralle is not what we expect it to be.  This tutorial takes a look at the performance of identical and dissimilar pumps and the effect of the system curve.  Part 1 compares the pumps and Part 2 factors in the system curve.

Download Part 1

Download Part 2

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Pascal's Principle - Paradox Lost


The pressure exerted by a colum of water depends upon its density and hight - - it has absolutely nothing to do with the its volume.  In this tutorial we take a close look at this paradox and provide various examples that support Pascal's Principle.

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Siphons & The Siphon Effect - That Sucking Sound


In this turorial we explain how a pipeline siphon works and provide several examples of how they can affect pump performance.

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How Curve Shape Can Influence Pump Selection


Some pump curves are very steep while others are pretty flat.  And, ofcourse there many inbetween.  This turorial looks at how the shape of a performance curve can influence a pump's performance in a particular application.

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Sewage & Wastewater


Click on a topic below for a brief description of its contents.

Air vs Oil Filled Sewage Pump Motors

Sewage Pump Impeller Selection

Vortex Action - How Lower Efficiency Can Reduce Cost

Lower Flow Nonclogs - Solids Handling Options


Pressure Sewer Systems

Lift Station Maintenance

Pump Cycle Time Calculator

Wastewater Pump Draw Down Calculator


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Pump Start and Cycle Time Calculator


See my April 2010 Pumps & Systems article for a description of this calculator.

Download   excel  xlsx

Download    excel xls

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Lower Flow Nonclogs - Solids Handling Options


There are times when pumps installed in lower flow applications need the ability to pass a full 3" spherical solid.  Should you install a 4" pump and run to the left of the performance curve?  Probably not.  This tutoral provides several options that will enhance pump life.

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Vortex Action - How Lower Efficiency Can Reduce Cost


Vortex pumps have a bad reputation in the engineering community because of their low hydraulic efficiency.  It turns out that their lower maintenance will often substantially reduce overall operating costs even though electrical costs may be slightly higher.  This tutorial explains vortex action and provides several examples that show why this type of pump may be a better choice.

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Variable Speed Pumping Systems


Click on a topic below for a brief description of its contents.

Variable Frequency 101

Resonant Frequency & Critical Speed

Resonant Frequency Demonstration

PID Control - What, Why, How ?

Balancing Voltage & Frequency - Fluxuating Flux

Variable Frequency Control - Other Advantages


Comparing Energy Consumption - To VFD or Not to VFD

VFD Pump Selection - Frequency vs RPM ?
Lift Station Level Control - Almost Utopia

Variable Fixed Speed Control - Float Switch Activation

VFD Pump Selection - Constant Pressure

VFD Pump Selection - Circulation

VFD Pump Selection - Level Control

Variable Speed Pump Selection - Parts 1 - 3



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Variable Speed Pump Selection - Parts 1 - 3


This tutorial takes a different approach to pump selection for VFD operation.  Part 1 addresses constant pressure / variable flow while Part 2 addresses variable pressure / variable flow.  Part 3 adds an elevation or constant pressure component to variable pressure / variable flow.

Download Part 1

Download Part 2

Download Part 3

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Lift Station Level Control - Almost Utopia

Back in the old days level control had nothing to do with saving energy.  In fact it was often a necessary evil.  With the advent of the VFD you may be able to achieve relatively constant flows and reduce the energy required.  This tutorial investigates the possibilities.

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Comparing Energy Consumption - To VFD or Not to VFD


If the goal of your VFD application is to reduce energy consumption, you have to do a careful comparison between VFD and constant speed operation.  This tutorial uses a constant pressure application to show you the proper way to do that comparison.

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Variable Frequency Control - Other Advantages


VFD's can reduce energy consumption by allowing a pump to run at the duty point required by the system and it can change that duty point in real time.  But they offer several other advantages that can often justify their use even if pump speed is not varied.  This tutorial explores those other advantages.

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Balancing Voltage & Frequency - Fluxuating Flux


We all know that a VFD varies the frequency seen by an electric motor.  That is how it varies the motor speed.  But, did you know that it must also vary the voltage?  If it did not, the magnetic field produced by the stator would become saturated and torque would become unreliable.  This tutorial explains the volts / hertz relationship that must be maintained by the VFD.

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Resonant Frequency & Critical Speed


The vibration that occurs in a pumping system due to resonance is not a good thing.  Resonance arrises when a variable speed pump reaches a critical speed.  It turns out that the first or lowest critical speed can be easily calculated from simple data provided by the manufacturer.  This tutorial explores resonant frequency and shows how to calculate the speed that causes it.

Download

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Pump Evaluation, Selection & Testing Tools


Click on a topic below for a brief description of its contents.

VFD Evaluation & Selection Tools

Variable Speed Pump Analysis Comprehensive - Excel

Parallel Pump Control Analysis - Excel

Parallel Pump Performance Analyzer 12/13 - Excel

VSPA50 - 50hz Variable Speed Pump Analyzer - Excel

VSPA60 - 60hz Variable Speed Pump Analyzer - Excel

Hertz: My Original Variable Frequency Sizing Tool - Excel

CPSA: An Older Centrifugal Pump Selection Assistant - Exel

WWPSA: A Variable Frequency Sizing Tool for Level Control - Excel

Pump Evaluation & Testing Tools

Series / Parallel Pumping Analyzer - Excel

SDSCA: Simplex / Duplex System Curve Analyzer - Excel


Radial Thrust Calculator - Excel

Suction Specific Speed & Suction Energy Calculators - Exce




Pump Field Test Calculator - Excel

Pump Cycle Time Calculator - Excel

Simple Wastewater Pump Draw Down Calculator - Excel

Wire To Water Energy Calculator - Excel

System Energy Calculator - Excel

Off BEP Energy Calculator - Excel

Other Calculators

Pump RPM, Hertz, Impeller Trim & Pulley Calculators - Excel

Submersible Motor Flow Velocity Calculator - Excel


TDH Calculator - Domestic Submersible Well Pumps - Excel

Pump & Motor HP At Lower Frequencies - Excel

Pipe & Fitting Friction Calculator - Excel

Lots of Pump & Motor Stuff Calculator - Excel
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Parallel Pump Performance Analyzer (12/13)


PPPA provides both across the line and variable speed analysis of up to eight pumps running in parallel.  See my December, 2013 Pumps & Systems article for a full description of its capabilities.

Download    excel xlsx

Download    50 Hz Version excel xlsx

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Pump Field Test Calculator


The 2013 version of my field test calculator allows detailed testing of pumps in the field.  There are four different tabs that directly address testing of above ground centrifugals (suction & discharge gauge method), submersible wastewater (discharge gauge method) and lineshaft turbines (discharge gauge method).  After entering the required data the calculator will calculate velocity, velocity head, TDH, average voltage, average current, unbalanced voltage and current, water HP, test point HP, pump efficiency and the cost per 1000 gallons pumped.  If multiple points are tested an H/Q test curve is generated automatically on page 3.  All equations used for calculations are shown on the spreadsheet.  Complete instructions are included.  See my Jan 2011 and May 2014 Pumps & Systems articles for more information.

Download    excel xlsx


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Submersible Motor Flow Velocity Calculator


This simple calculator allows you to enter the motor OD and casing ID for a submersible well pump application.  It then calculates the flow velocity past the motor, the effective flow ID and the friction per motor foot.

Download    excel xlsx

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Wastewater Pump Draw Down Calculator

Draw Down is a common technique for evaluating wastewater pump performance.  This simple, Excel program standardizes the measurement process and also calculates TDH.  Both flow and TDH are required to evaluate pump performance and locate the operating point on the pump H/Q curve.  Discharge velocity head is also calculated and included in the TDH calculation.  See my December 2011 Pumps & Systems article for more information.  The Drawdown combo calculator is designed for older wells that use a partition to accommodate both wet and dry pits in the same well.  A drawing on the sheet explains their use.

Drawdown    excel xlsx  updated 12/13

Drawdown combo    excel xlsx   updated 12/13

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  Pump RPM, Hertz, Impeller Trim & Pulley Calculators

These four calculators use the affinity laws to calculate changes in pump flow, head & BHP based upon changes in pump speed or impeller diameter.  Follow the directions for data entry and then click on the tabs to view the H/Q curves.  (These calculators were updated on 11/17/12.  The origional versions were test versions that were uploaded accidentally.  If you downloaded the calculators prior to 11/17/12, you should replace them with the current ones.)

RPM Calculator    excel xlsx

Hertz Calculator    excel xlsx

Trim Calculator    excel xlsx

Pulley Calculator    excel xlsx

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Pump Start and Cycle Time Calculator


See my April 2010 Pumps & Systems article for a description of this calculator

Download    excel xlsx

Download    excel xls

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Pump & Motor HP At Lower Frequencies


When pump speed is reduced, the required HP reduces as the cube of the change in speed.  When a VFD reduces motor speed the available HP is also reduced.  In cases where lower HP motors are used to run a pump at some maximum frequency, it is important to make sure that the HP available at that frequency is sufficienct.  This calculator will show you the required vs available HP.  See my January 2013 Pumps & Systems article for more information.

Download    excel xlsx

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Pipe & Fitting Friction Calculator


There are many online friction calculators available but, there are times when you cannot go online to use them.  Although not as comprehensive as some of the online versions, this calculator allows you to compute the friction for up to three piping segments.  It also allows you to select the valves and fittings for each segment.

Download    excel xlsx

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Lots of Pump & Motor Stuff Calculator


This calculator allows you to compute lots of pump and motor stuff from catalog and field test data.  On the pump side it computes specific speed, suction specific speed, min & max acceptable flow, actual pump efficiency and cost per 1000 gallons pumped just name a few.  On the motor side it computes HP, torque, kVA, power cost per hour, voltage unbalance and current unbalance just to name a few.  It also includes a simple pipe friction calculator.  You will have to check it out to see the rest.

Download    excel xlsx

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Electricity, Motors, & Controls


Click on a topic below for a brief description of its contents.


AC Power

The AC Induction Motor

The Single Phase Induction Motor


The Cowern Papers
Power Factor - Parts 1 & 2

Process Control - Parts 1 & 2

Confusing Units of Measure - Work, Power,  & Torque

Inertia - Confusing Units Revisited



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Confusing Units of Measure - Work, Power, & Torque


This tutorial could be located under other categories because it applies to all rotating machinery.  It compares the units of measure, used in a rotational environment, with their linear cousins.  Hopefully it makes them a little more understandable.

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Inertia - Confusing Units Revisited

Rotational inertia is quite different than its linear cousin but there are times when we need to understand its relationship with torque.  This tutorial investigates rotational inertia, compares it with linear inertia, and uses some simple examples to show the effects of its contributors.

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Process Control - Parts 1 & 2


This two part tutorial attempts to make process control understandable.  Part 1 takes a look at very simple control algorithms while Part 2 investigates the more complex PID control used in VFD applications.  Also see "PID Control" under the Variable Speed section for another approach.

Download Part 1

Download Part 2

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Power Factor - Parts 1 & 2


This tutorial takes a detailed look at the cause and effects of PF.  Part 1 (Electricity Behaving Badly) explains PF and it causes.  Part 2 (Electricity Behaving Better) investigates potential fixes and shows their effect.

Download Part 1

Download Part 2

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VAST
(Various And Sundry Things)


Click on a topic below for a brief description of its contents.

Publications From a Previous Life

Other Educational Sites

Pump Calcs

Operators Guide to Centrifugal Pumps

SALINITY - The Very Best Finishing Salts

Hawaiian Vacation

Pump Ed 101 Background Image
Convert - Desktop Conversion Utility

Why Newton Invented Calculus

Sizing Pumps After Sunset

PumpTech Pipeline Newsletters & Product Info

Web Site Development & Hosting



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The Tutorials

The tutorials and topics presented here were developed over the past twenty years.  Several were written for my own employees in an effort to further their understanding of the equipment and applications that were our life's blood.  Others were written specifically for specifying engineers so that they could gain an unbiased understanding of different options.  But, most were developed to provide information for the overall pump community.  So far, they have been well received and I have shared them via one web site or another since 1997.  Many emails from around the world have offered compliments, corrections, and suggestions.  Please keep them coming.

Some are short and simple -- "The Self Priming Pump", for example, gives a brief overview of self priming pumps and the applications for which they are intended.  These will usually reference another tutorial for more detailed study.  Others, like "AC Power", are far more detailed and present a thorough overview from generation to consumption.  "Hertz" and "HPSA", on the other hand, are designed to be interactive learning and sizing tools.  "Centrifugal Pump Dynamics" is html based and uses animations to get its points across.  My "Pumps & Systems" magazine articles offer a short review of a broad range of pump, motor and control topics.  Some of the "two part" articles, such as "Power Factor" provide an in depth review.

The "Puzzler" is a totally different animal.  It uses the findings of simple Physics to help explain some of the every day and, even more complex phenomena that we encounter in  pumping applications.  I developed the Puzzler as the basis for my weekly "lunch & learn" seminars that I presented to my employees.  The beauty of the "Puzzler" is that it promotes learning rather than memorization.  For example, why memorize a fact such as -- the head produced by a centrifugal pump changes as the square of a change in speed -- when the "falling body" equation shows you why?

If you have questions or suggestions, please drop me an email.

Joe Evans

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THE PUZZLER - Joe Evans, Ph.D 

Have you ever wondered why the pressure of a fluid flowing in a pipe decreases as its velocity increases? Could it have something to do with why airplane's fly? Why does 115 volts plus 115 volts equal 230 volts in some cases, but only 208 volts in others? Doesn't the pressure that a liquid exerts have anything to do with its volume? When is a watt not a volt-amp?  Is centrifugal force really a farce?   How come liquid friction, but not solid friction, is affected by velocity and surface area?

If you find these and other questions relating to pumps, motors, and electricity especially titillating, you are going to love the Puzzler. The Puzzler poses a pointed question, but that question is just the tip of the iceberg! The discussion that follows explores not only the question but also the physics surrounding it.

The current Puzzler Series consists of more than forty brain teasers designed to expand your knowledge of mechanics, hydraulics, and electricity.  The dowload button is below the titles.

Basic Puzzlers

The Up And Down Puzzler (Initial & Final Velocity)
The Restricted Pipe Puzzler (Bernoulli Principle)

The Water Column Puzzler (Hydrostatic Paradox)
The Sinking Float Puzzler (Buoyancy)

The Barrel Burst Puzzler (Pascal’s Experiment)
The False Force Puzzler (Centrifugal Force)

The My Shaft’s Bigger Than Yours Puzzler (Torque)
The WK2 Puzzler (Inertia)
The Belt Tightening Puzzler (Mechanical Friction)
The Warranty Puzzler (Time Dilatation)

The Water Supply Puzzler (Exponential Function)

Hydraulic Puzzlers

The Affinity Puzzler (The Affinity Laws)
The Impeller Trim Puzzler (Peripheral Velocity)

The Variable Speed Puzzler (Variable Frequency Control)
The Crazy Impeller Puzzler (Runners)

The Hot And Cold Puzzler (Liquid Friction & Viscosity)


The Worn Pump Puzzler ( Axial & Radial Thrust)
The Differing Pressure Puzzler (Eductors)

The Corrupted Curve Puzzler (Positive Displacement Pumps I & II)
The Leaking Pump Puzzler (Hydraulic Ram)
The Air Lock Puzzler (Siphon)

The Drawdown Puzzler (Hydropneumatic Tanks)
The Priming Puzzler (Centrifugal Pump Priming)
The Suction Air Puzzler (Pipeline & System Air)

Electrical Puzzlers
 
The Mumbo-Jumbo Puzzler (Motor Insulation)

The Right Motor Puzzler (Service Factor)
The Kill A Watt Puzzler (Reactance)

The Starting Puzzler (Motor Starting Techniques)
The Changing Voltage Puzzler (Three Phase Connections)

The Distorted Wave Puzzler (Harmonics)
The Syntax Puzzler (Boolean Logic)

The Grounded Pump Puzzler (Corrosion Protection)
The Country Boy Puzzler (Phase Generator)

The 4” Motor Puzzler (Tesla Meets Newton)

Download The Complete Puzzler Series (918 K Acrobat Document)    

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A BRIEF INTRODUCTION TO CENTRIFUGAL PUMPS - Joe Evans, Ph.D                        

This short course is intended for the new comer to the centrifugal pump environment. It is also a good review for those who are a bit rusty. Topics covered include the performance curve, centrifugal force & peripheral velocity, series operation, parallel operation, the affinity laws, friction, specific gravity & viscosity, suction lift, and NPSH. It also references several "Puzzlers" for further study of specific topics.

Download ( 1001 K Acrobat Document) 

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CONSTANT PRESSURE BOOSTER SYSTEMS - Joe Evans, Ph.D

This tutorial will allow you to enter the realm of constant pressure and the booster systems that support it.  It starts with a brief overview of the differential pressure booster and then takes a look at PRV controlled simplex, duplex, and triplex constant pressure systems.  From there it moves on to VFD control and the advantages it can offer.  Topics covered include tank vs tankless systems, sequencing, pressure vs flow control, and pump selection.  If you are unfamiliar with the VFD, download "Variable Frequency 101"  as you will need an understanding of their operation for the second half of this discussion.

Download ( 263 K Acrobat Document)

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THE SELF PRIMING PUMP

This brief overview discusses the advantages and limitations of self priming centrifugal pumps.  It also references a "Puzzler" for a more detailed understanding of centrifugal pump priming.

Download ( 108 K Acrobat Document)

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THE AC INDUCTION MOTOR - Joe Evans, Ph.D

This introduction is intended for those with little or no background in electric motors. It begins with the very basics including magnetism, direct current, and the operation of a simple DC motor. From there it moves on to alternating current, induction, and the operation of a simple AC motor. It concludes with a discussion of work, torque, and horsepower. It is an excellent primer for some of the electrical "Puzzlers".  For a more comprehensive review of induction motors, see my five part series (March - July 2011) on the "Pumps & Systems Magazine Columns" page of PumpEd101.

Download ( 422 K Acrobat Document)

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THE SINGLE PHASE INDUCTION MOTOR - Joe Evans, Ph.D

The major difference in single and three phase motors is that the single phase motor requires some sort of starting mechanism to get it rotating.  This overview looks at four of the most popular starting (and two running) techniques and the pros and cons of each.  It also includes a discussion of single and three phase rotational fields.  It is aimed at the pump professional who works with single phase submersible wastewater pumps, well pumps, and small centrifugals.  For a more comprehensive review of induction motors, see my five part series (March - July 2011) on the "Pumps & Systems Magazine Columns" page of PumpEd101.

Download ( 547 K Acrobat Document)

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AC POWER - Joe Evans, Ph.D

Why is AC power the standard in the US?  What is the difference between single phase and three phase sine waves?  Why does a voltmeter read 115V, 230V, or 460V when the actual voltage is quite a bit higher?  How does a transformer work? What is the difference between Wye & Delta versions?  Do resistive and inductive circuits behave differently?  What is power factor and what does it have to do with reactance?  How can capacitive reactance be used to correct the problems caused by inductive reactance? This short course is designed for the pump professional who wants to gain a basic understanding of AC power and its application to electric motors.  See my June through September 2010 Pumps & Systems magazine articles for additional reading.

Download  ( 397K Acrobat Document)

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VARIABLE FREQUENCY 101 - Joe Evans, Ph.D

Why not debunk some of those myths surrounding VFD's and learn how simple they really are.  Did you know that they have been around, in one form or another, since the invention of the AC induction motor?  This short introduction will help the pump professional gain an understanding of their inner workings, potential problems, and some of the applications for which they are well suited. Topics include: the relationship between frequency and motor windings (poles), Pulse Width Modulation (PWM) output, effective voltage, insulation stress, harmonics, bearing damage, and typical applications in the pumping environment.

Download (368 K Acrobat Document) 

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CENTRIFUGAL PUMP MOTOR SELECTION, INSTALLATION, & START UP - Joe Evans, Ph.D

The vast majority of failures of new electric motors can be attributed to improper selection, installation, and start up. Although factory defects do occur, they are rare and are quite apparent upon tear down and inspection.  This short publication is a guide to the proper selection, installation, and start up of new and replacement centrifugal pump motors.  (This tutorial was updated on 2/12/06)

Download ( 35 K Acrobat Document)

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RESONANT FREQUENCY 

The resonant frequency of and object is the frequency at which it begins to vibrate of its own accord.  In this demonstration, by the University of Michigan Physics Laboratory, sound waves are porduced at various frequencies and projected upon a wine glass.  A strobe light allows us to view its vibrations and eventual shattering.  Download "Variable Frequency 101" for a detailed explaination of resonant frequency and its potentially damaging effect upon pumps.

Download ( 3.48M Quick Time Movie)

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AIR VS OIL FILLED SEWAGE PUMP MOTORS - Joe Evans, Ph.D

Some manufacturers believe that filling a motor with oil is the only way to go while others think air to be a better solution (pun intended). This paper takes an honest look at these two popular submersible sewage pump motor designs and compares the advantages and disadvantages of each. Topics covered include motor efficiency, heat transfer, bearing lubrication, maintenance, and environmental concerns.

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SEWAGE PUMP IMPELLER SELECTION - Joe Evans, Ph.D                                                    

This overview discusses the various impeller designs used in raw sewage pumping applications.  Designs covered include the major members of the radial vane family, the vortex impeller, and the centrifugal screw.   Topics include centrifugal impeller basics, design pros & cons, operational characteristics, and application selection criteria.  

Download (339K Acrobat Document)


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PRESSURE SEWER SYSTEMS:  CENTRIFUGAL VS POSITIVE DISPLACEMENT - Joe Evans, Ph.D

During the past thirty years, low pressure grinder pump sewer systems have become a popular alternative to traditional gravity systems. The two basic pump designs, centrifugal and positive displacement, used in these systems are as different as night and day. This short article discusses the operating characteristics of centrifugal and positive displacement grinder pumps when installed in a pressure sewer system.  Topics covered include pipeline velocity, unvarying vs dynamic flow, self limiting system pressure, operating power, and impeller / cutter design.

Download (115K Acrobat Document)

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HERTZ:  A VARIABLE FREQUENCY / SPEED CALCULATOR AND PLOTTING TOOL - Joe Evans, Ph.D

Hertz is an Excel program that allows you to illustrate the laws of affinity, perform a design point calculation, and plot centrifugal pump performance curves as a function of frequency or RPM.  It is named for the German physicist, Heinrich Hertz, who discovered the very low frequency electromagnetic radiation we now call radio waves. After many decades of cps (cycles per second) we are finally giving him credit.

Directions for its use can be found at the bottom of the spread sheet.  "Auto Plot" automatically plots the 60, 55, 50, 45, 40, 35 and 30hz  performance curves (in feet and PSI) for the data you entered.  You can also enter a system curve so that you can evaluate your selection.  Instructions for custom plots are also included.
 

Download (115K Excel Document)

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Variable Speed Pump Analysis - Joe Evans, Ph.D

VSPAnalysis is a comprehensive excel program that will allow you to view the operational characteristics of a centrifugal pump operating under VFD control and allows you to select the best pump for a particular application.   It produces variable speed curves showing head, efficiency, horsepower, KW and cost per 1000 gallons pumped.  It has complete instructions and a discription of the included example.  For more information see my Jan 2011 Pumps & Systems magazine article.  The standard version plots the variable frequency curves from 30-60hz in 5hz increments.  "VSPAnalysys 2hz" plots the variable frequency curves from 40-60hz in 2hz increments.


VSPAnalysis

VSPAnalysis 2hz

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Variable Speed Parallel Pump Control Analysis - Joe Evans, Ph.D

VFPPA is excel programs that allows you to view the operational characteristics of two or more centrifugal pumps operating under VFD control.  It will help you determine the most efficient operating method (synchronous or individual speed control).  It has complete instructions and a discription of the included example.  For more information see my Oct 2010 Pumps & Systems magazine article.


VFPPAnalysis 07 version

VFPPAnalysis 03 version

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CPSA:  Centrifugal Pump Selection Assistant - Joe Evans, Ph.D

CPSA is an abbreviated and simpler version of Hertz but, also has some additional features.  It plots a system curve and  the 60 - 30 hz curves (in feet and PSI) for the pump selected.  There is nothing else to muddle the picture and there is no need to scroll side to side or up and down.  It also asks for the hydraulic efficiencies for each of the flow points and, in return, prints the HP required as "data lables" on each of the frequency curves.  This allows you to quickly determine the power savings for an application using a given pump.


Download  (121K Excel Document)

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VSPA-50:  Variable Speed Pump Analyzer 50hz - Joe Evans, Ph.D

VSPA-50 is an international version of CPSA.  It plots a system curve and  the 50 - 25 hz performance curves (in any unit of measure).  It can accomodate up to eight H/Q points.  If you enter the power requirement for each of the flow points for the 50hz curve, it will generate "power data lables" on each of the frequency curves.  This allows you to quickly determine the power savings for an application using a given pump.  See my May 2009 Pumps & Systems magazine article for additional information.


Download  (116K Excel Document)

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VSPA-60:  Variable Speed Pump Analyzer 60hz - Joe Evans, Ph.D

VSPA-60 is an international version of CPSA.  It plots a system curve and  the 60 - 30 hz performance curves (in any unit of measure).  It can accomodate up to eight H/Q points.  If you enter the power requirement for each of the flow points for the 60hz curve, it will generate "power data lables" on each of the frequency curves.  This allows you to quickly determine the power savings for an application using a given pump.  See my May 2009 Pumps & Systems magazine article for additional information.


Download  (116K Excel Document)

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Radial Thrust Calculator - Joe Evans, Ph.D

The unbalanced radial thrust that arises in a single volute pump is lowest at or near BEP depending upon the Pump's Specific Speed (Ns).  But as operation moves away from BEP (especially to the left) the net radial thrust increses quickly.  Unbalanced radial thrust can cause increased shaft deflection which can lead to increased seal, bearing, and wear ring wear.  In some cases it can cause the shaft to break.  This calculator allows you to quickly calculate the radial thrust in PSI at any point on a pump's H/Q curve.  See my Jan 2010 Pumps & Systems magazine article for additional information.


Download  (58K Excel Document .xlsx)

Download  (58K Excel Document .xls)

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Suction Calculators - Joe Evans, Ph.D

Two useful pieces of information that can be used to identify pumps that are prone to cavitation due to suction recirculation are Suction Specific Speed (S) and Suction Energy (SE).  This calculator will allow you to calculate both.  For more information on S see Terry Henshaw's Oct - Dec 2009 Pumps & Systems
articles on NPSH and Suction Specific Speed.  You can read them at www.pump-zone.com
See my Feb 2010 Pumps & Systems magazine article for additional information.  The calculators were updated on 3/31/11.


Download  (2.4M Excel Document .xlsx)

Download  (480K Excel Document .xls)

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CONVERT:  A DESKTOP CONVERSION UTILITY

Convert is a Windows based, desktop, conversion utility that is one of the most comprehensive I have run across.  It allows you to convert just about any unit of measure to dozens of others.  It also allows you to set up your own custom conversions.

It was eveloped by Josh Madison ( http://www.joshmadison.com/software/convert/ )


Download  (156k WinZip file - unzips to a 548k exe file)


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VFD Pump Selection - Constant Pressure - Joe Evans, Ph.D

This tutorial goes into a fair amount of detail concerning the proper selection of booster pumps for VFD applications.  It starts by comparing a PRV controlled booster with one under VFD control and then outlines five rules that should be followed during pump selection.  It ends with examples of good and poor selections.  Another discussion of this topic can be found in the "Pumps & Systems" section of this site.

Download  (215K Acrobat Document)

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VFD Pump Selection - Variable Flow / Variable Pressure - Circulation - Joe Evans, Ph.D

With this tutorial, we begin our discussion of applications that require varying flows but do not require constant pressure. Circulation is one of the more popular variable speed applications for many reasons.  We begin with a discussion of closed loop applications, show a typical system curve, and then illustrate the pump curves used for single and variable speed operation.  We then move on to open loop systems and provide  similar information.  Another discussion of this topic can be found in the "Pumps & Systems" section of this site.

Download  (183K Acrobat Document)

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VFD Pump Selection - Level Control - Joe Evans, Ph.D

In this tutorial, we take a close look at waste water pump down applications and show how they can often benefit from conversion to level control.  We begin with a discussion of wet and dry pit installations and show an example of the pumps used in pump down applications.  We then show the same pump operating in a level control environment.  We end with some guidelines on pump selection.  Another discussion of this topic can be found in the "Pumps & Systems" section of this site.

Download  (232K Acrobat Document)

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TDH Calculator - Domestic Submersible Well Pumps - Joe Evans, Ph.D

The TDH Calculator is a very simple visual that allows easy calculation of the TDH required for domestic submersible well pump applications.  It breaks down TDH into six, individual components and illustrates their relationship both above and below ground.  They are available as a PDF document or Excel spreadsheet.  The Excel version performs interactive calculations.

Download  (54K Acrobat Document)

Download  (Excel Spreadsheet)

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Lift Station Maintenance for the Complete Idiot - Steve Cottrell, Enco Southwest Inc.

Don't let the title offend you (Dummies was already taken).  Steve's guide is written for that building maintenance guy who wakes up one morning and finds that he now has responsibility for a submersible lift station!  It is simple, straight forward and will keep that station up and running.  Steve can be reached at:   steve@encosouthwest.com

Download  (1120K Acrobat Document)

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Centrifugal Pump Intro for PP (Part 1 Elementary Mechanics & Hydraulics) - Joe Evans, Ph.D

This Power Point presentation is designed for audiences with a "limited" knowledge of centrifugal pumps.  It can be presented in as little as an hour or as a morning or afternoon class if you go into more detail.  Use the script to guide you through the slide show.  Don't have Power Point on your PC?  No problem - - download the pdf version and show it as slides on  a PP projector or TV monitor.

As the title implies, this tutorial presents the basic mechanics and hydraulics of centrifugal pump operation.  It begins by dispelling the myth of "centrifugal force" and shows that acceleration of a fluid is its sole purpose.  It then moves on to a discussion of the pump "curve" and shows examples of series and parallel operation.  It touches on specific gravity and why we typically rate pump performance in feet of head.  We review the laws of affinity and illustrate them with a pump operating under VFD control.  We finish with a discussion of suction conditions and liquid friction.


Download  (707K Power Point)         DownLoad  (177K pdf Version)       Download  (92K pdf Script)

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WWPSA  A Variable Frequency Sizing Tool - Level Control - Joe Evans, Ph.D

The Wastewater Pump Selection Assistant is an excel program that allows you to evaluate a submersible or dry pit pump that will be used in a level control application.  You can enter up to eight flow and head points from a 60 hz performance curve and then view its operating curves from 30 to 60 hz.  If you enter a system curve and the "pump down" elevation you can also view the same pump operating in a pump down environment.  Finally, if you enter the hydraulic efficiencies for each point, brake horsepower will be calculated automatically and displayed as "data labels" on each of the curves.  Scroll down to the bottom of the spreadsheet for complete directions and notes on the example that is included.

Download  (128K Excel Document)


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Cavitation - A Largely Misunderstood Phenomenon - Joe Evans, Ph.D

The goal of this tutorial is to help you gain a intuitive understanding of the cavitation process and its causes.  I will leave its prevention to the many articles that already exist.  Since boiling is the precursor to cavitation, we begin by taking a look at some of the properties of water and their role in the cavitation process.  We then put NPSH into perspective and  review some of the dynamics of centrifugal pump operation that also directly affect the process.  We conclude with a discussion of the different types of centrifugal pump cavitation and the conditions that can cause them to occur.  Another discussion of this topic can be found in the "Pumps & Systems" section of this site.

Download  (519K Acrobat Document)


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About the Author

Joe Evans lives in beautiful Rhododendron Oregon and works for PumpTech Inc.  Since entering graduate school, a continuing interest has been one of computer control of mechanical and electronic systems.  It began with the introduction of the minicomputer, in the late sixties, and continued with the advent of the PC and PLC in the eighties and nineties.  He accidentally entered the pump industry in 1986, and has been trapped there since.  He is passionate about the sharing of knowledge and its ability to replace memorization with understanding.  Click below if you would like to view a resume of his academic and professional experience.  For a little history, click on the "Publications From a Previous Life" link which can be found in the VAST section of my home page.

Download  (Resume Acrobat Document)


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The Cowern Papers

Ed Cowern received his BS in Electrical Engineering from MIT and is a district manager for Baldor.  His clear and understandable technical papers on electricity and electric motors make them a very useful reference.

Download  (1 MB Acrobat Document)


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Web Site Development & Hosting

Pueo Advanced Media offers web site development & hosting and is the brain child of my son Jamie.  Whether you need a "plain Jane" site like mine (well maybe not quite as plain as mine) or something much more sophisticated, he can provide it at a reasonable cost.  Hosting is also inexpensive and starts at under $ 7.00 per month.  Click below and take a look at some of his work.  And, I am sure that he would want to make it perfectly clear that he did not do mine (but he does host it).  I have to take full responsibility for its "no frills" look.

Pueo Advanced Media


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Why Newton Invented Calclus - Joe Evans, Ph.D

Math -- one of those four letter words that can bring on anxiety attacks.  It is sad that such a useful science has gotten such a bad rap.  But, quite frankly, you can blame it on the teachers for it is they who have missed this great opportunity.  This short tutorial provides a brief history of calculus and gives some every day examples of why is still needed today -- even in the pump industry.  It also takes a few jabs at our educational system for not doing a better job of presenting math in high school and college.  But, most importantly, it promotes less complex math (algebra) as a component that can help us better understand basic hydraulics and mechanics.

Download  (122K Acrobat Document)

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Three Phase Motor Starting Techniques - Joe Evans, Ph.D

New comers to the pump industry are often unfamiliar with many of the three phase motor starting techniques that employed “pre-semiconductor” technology.  Surprise - - most of them are still in use and will probably be here for some time to come.  The primary purpose of alternative starting techniques is to reduce the system loading during starting.  The typical AC induction motor has an inrush current, during starting, that is about five to seven times that of run current.  Today, the VFD can provide a soft start and stop automatically just by ramping the input frequency.  In the past it was not always that easy.  This tutorial will review the most common methods of motor starting.

Download  (282K Acrobat Document)

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Positive Displacement Pumps - Parts 1 & 2 - Joe Evans, Ph.D

There are many pump designs that fall into the positive displacement category but, for the most part, they can be nicely divided into two basic groups.  The reciprocating group operates via pistons, plungers, or diaphragms while rotary pumps use gears, lobes, screws, vanes, and peristaltic action.  Their common design thread is that energy is added to the pumped fluid only periodically where, in dynamic pumps, it is added continuously.  See my September & October 2009 Pumps & Systems magazine articles for additional reading.

Part 1 of this tutorial covers reciprocating designs while Part 2 deals with rotary units.

Download  (Part 1 - 187k Acrobat Document)     
Download  (Part 2 - 138k Acrobat Document)

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Viking Pump PD Pump White Papers

In the mid 80's Viking Pump Company published a couple of very useful white papers for positive displacement pump users.  AD-19 was all about NPSH while AD-6 covered pressure and vacuum.  Both are available below in pdf format.

Download  AD-19 2 mb pdf

Download  AD-6  2 mb pdf



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Sizing Pumps After Sunset - Joe Evans, Ph.D

I really had to think long and hard about putting this up on my web site.  Hopefully you will never have to use it but, it can allow you to size a replacement end suction, centrifugal pump with a minimal amount of information.  It uses something I call BEP sizing and includes several "family" curves that are made up of average BEP flows and heads from almost 400 individual pumps.  If you decide to download this tutorial, use it carefully.

Download  (79k Acrobat Document)


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Background Image - Impellers

The background on my home page is one I developed for my first web site in the mid 90's.  It provides a bit of pump based art work without detracting from the content.  Below are a couple of images of the area where I live.  Mt. Hood is a dormant volcano that last erupted in 1907 and is the second most climbed mountain in the world.  It is surrounded by the 1.2 million acre Mt. Hood National Forest which has over 1200 miles of hiking trails.  Most importantly, it is in my back yard!  The image on the left is the North side as seen from Lost Lake.  The one on the right is the Sandy river which originates in
the glaciers and runs through our community.
                                                       

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Series / Parallel Pumping Analyzer with Autoplot - Joe Evans, Ph.D

The resulting pressure and flows obtained when identical pumps are operated in series or parallel can be intuitively obvious. But, when those pumps are not identical, our analog brains often need to see a graphical presentation of those results.  The Series / Parallel Calculator is an Excel program that allows you to view the combined performance curves of identical and similar pumps when running in series and parallel installations.  It also allows you to enter a system curve so that you can  evaluate their performance.  After you download and start the program, scroll down for detailed instructions and a description of the example that is included.

Download  (130k Excel File Revised 5/20/06)


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VFD Pump Selection - Frequency vs RPM ? - Joe Evans, Ph.D

I receive several emails each month asking why my VFD sizing programs (Hertz, Hertz VHF, HPSA, & PPSA) show the resulting curves in hz rather than RPM.  This short paper explains my reasoning.

Download  (55k Acrobat File)


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Centrifugal Pump Efficiency - What, How, Why, When ? - Joe Evans, Ph.D


In this tutorial, we will investigate several aspects of centrifugal pump efficiency.  First I will define efficiency and give some examples.  Next we will examine some of the design criteria that ultimately dictate the efficiency exhibited by a particular pump.  We will also try to make that somewhat nebulas quantity, known as specific speed, more meaningful.  I will also show its effect on the shape of a pump’s performance and power curves.  Finally, we will discuss the importance of (or, sometimes, unimportance) of efficiency as it relates to a particular application or process.  We will also illustrate the relationship of efficiency, head, and flow as they apply to both steep and flat performance curves and their roles in constant and variable speed applications.  We will end with a brief look at the combined efficiency of a pump and its driver.  For a more recent look at this topic see my Feb through July 2012 Pumps & Systems magazine articles.

Download  (461k Acrobat File)


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Waterhammer - Its All About Conserving Energy - Joe Evans, Ph.D


Most of us are familiar with the phenomenon known as waterhammer (water hammer) but few realize how destructive its force can be.  Neither can we visualize some of the events that lead to its inception and those that occur afterwards.  Did you know that waterhammer is a real life example of one of Physics' most fundamental laws?  In this tutorial we will investigate both the cause and effect of waterhammer.  We will also look at several methods of mitigating its damage and inception.  Another discussion of this topic can be found in the "Pumps & Systems" section of this site.

Download  (233k Acrobat File)


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Educational Seminars &  Training


The recipie for Pump Ed 101's educational seminars and training is a simple one.  Combine the subject matter with many years of hands on experience, a dash of simple physics, a bit of history, and a generous portion of practical examples.  Stir well and sprinkle with interaction.  The result is a learning experience for everyone involved, regardless of their prior knowledge of the subject.

The seminars shown below have been presented to a wide range of audiences over the past twenty years.  They are updated continuously and the current Power Point versions include lots of Java based animations that can often clarify many of those, otherwise, subtle points.  My audiences include engineering firms, refineries, utilities, AWWA, WEF, MEA, NGWA, RWA, and other pump oriented organizations.  Drop me an email if you are interested in an on site seminar or have questions.

Click below to download the pdf that describes the seminars that are approved for CEU credits in Oregon, Washington & Idaho.  Depending upon the acrediting agency, presentations must be a minimum of one or three hours.   Half day seminars can be a mix of various one hour presentations.  Seminars are sponsored by PumpTech and can be presented in Washington, Oregon, Idaho and parts of Montana.


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Centrifugal Pump Dynamics - Joe Evans, Ph.D


"Dynamics - the branch of mechanics that deals with the motion and equilibrium of systems under the action of forces related to motion."  Well, no wonder you have never investigated this before - - it sounds pretty boring!  But, believe or not, dynamics is actually quite interesting (and simple) and it is the key to understanding how centrifugal pumps work.  This short tutorial will allow you to fully appreciate what goes on inside those pumps - - all the way from the inlet to the discharge.  I have chosen the html format for this one so that I can take advantage of some imbedded animations and links to several other sites that will help us visualize what is going on.  Make sure that Java and Flash are enabled.  It is also available as a pdf document but you will not be able to take advantage of the animations.  Enjoy!

Dynamics Html Version                     Dynamics Acrobat Version (98k pdf file)


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Anti VFD (Beware of the Nazi's)


As you search the web for more information on variable frequency applications you might get the feeling that we have reentered the era of pre WWII.  Some of the sites out there profess that VFD's have no rightful place in our society and that there is no pump application worthy of their use.  Most of these opinions come from those who offer competing products and they will show a pump curve or power analysis that proves that their product can always do a better job.  I have even read some tax payer sponsored research that goes way over the line.  One concluded that magnetic coupling systems offer power savings similar to that of VFD's.  This certainly may be true in some instances but, the data used in this particular study was so skewed even Enron would have been concerned !

The same thing can happen on the other side of the aisle - - but it is usually due to a lack of knowledge rather than deceit.  Many of the VFD articles in the trade press tend to be written by VFD manufacturers.  And, although they have some pretty smart people, most have a limited knowledge of pump applications. Therefore the examples given tend to be more theoretical than practical.

Here is a good rule of thumb:  no single application control technique will always be the best choice for a given application.  If someone tells you that theirs is always best - - take them off your "favorites" list.  In my variable frequency tutorials, I try to use pump curves that are more typical rather than one that is "perfect".  This allows you to compare application results in a more realistic light.  


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PID Control - What, Why, How ? - Joe Evans, Ph.D



The P (proportional) in PID is not too frightening but, what about those other two letters?  Are not the integral and derivative parts of that mathematics known as calculus?  And, isn't calculus frightening?  Well fear no more because this "layman's" discussion of PID control will help you understand what it is, why we use it, and how it works.  We start with a discussion of open and closed loop control and give examples of each.  We then move on to proportional control and the applications it supports.  We end with a discussion of the integral and derivative functions and how they can temper the, sometimes, unruly nature of the proportional controller.  Another discussion of this topic can be found in the "Pumps & Systems" section of this site.


Download  (75k Acrobat File)


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Variable Fixed Speed Control - Float Switch Activation - Joe Evans, Ph.D



So, your waste water application will not lend itself to level control operation.  Or, maybe you just prefer float switches over transducers and ultrasonic devices.  Whatever the reason, VFS or variable fixed speed control might be a viable alternative to that pump down application.  Today you can combine an inexpensive VFD with standard float switch technology and get a multispeed pumping system that can increase application flexibility and efficiency.  This short tutorial takes a look at VFS control and how it compares to standard pump down applications.


Download  (92k Acrobat File)


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SDSCA - Simplex / Duplex System Curve Analyzer - Joe Evans, Ph.D



There can be times when we over estimate the flow expected during parallel operation of two non-clogs.  SDSCA is an excel spread sheet that allows you to analyze the operation of the same non-clog running under simplex and duplex (parallel) operation.  It will generate a system curve based upon the information entered and give you the head required at design flow.  You can then enter the curve data for a selected pump and the simplex and duplex operational curves will be plotted against the system curve.  Scroll down for detailed instructions.  The data used in the example can be found under the "Notes" tab.


Download  (80k excel file)


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Pumps & Systems Magazine Columns - Joe Evans, Ph.D

In September of 2006 I began contributing a monthly educational column to Pumps & Systems Magazine.  The unedited versions will be available here in pdf format as they are published.  Some of these columns are also listed under the proper category on the home page and include a short description.  Most, however, are not so be sure to browse through all of the titles below.  If you do not already subscribe to P & S you can do so online at http://www.pump-zone.com/

Sept 2006 - Centrifugal Farce & Affinity                                            

Nov 2006 - Preservation of Efficiency - Affinity Revisited                   Dec 2006 - Liquid Friction - The Tarantino Effect

Jan 2007 - When Bubbles Don't Burst - Why Cavitation is Damaging      Feb 2007 - Pascal's Principle - Paradox Lost

Mar 2007 - Balancing Voltage & Frequency - Fluxuating Flux                 Apr 2007 - Comparing Energy Consumption - To VFD or Not to VFD

May 2007 - How Curve Shape Can Influence Pump Selection                  Jun 2007 - Power Factor Part 1 - Electricity Behaving Badly

July 2007 - Power Factor Part 2 - Electricity Behaving Better                Aug 2007 - Vortex Action - How Lower Efficiency Can Reduce Cost

Sept 2007 - Lift Station Level Control - Almost Utopia                            Oct 2007 - Confusing Units of Measure - Work, Power, & Torque

Nov 2007 - Siphons and the Siphon Effect - That Sucking Sound            Dec 2007 - Variable Frequency Control - Other Advantages

Jan 2008 - Process Control Part 1 - Smart and Not So Smart Control       Feb 2008 - Process Control Part 2 - Even Smarter Control

Mar 2008 - Parallel Pumping Part 1 - Parallel and  Not So Parallel           April 2008 - Parallel Pumping Part 2 - Other Considerations


May 2008 - Net Positive Suction Head - NPSHa & NPSHr                       June 2008 - Two Steps to Longer Pump Life - Part 1

July 2008 - Two Steps to Longer Pump Life - Part 2                               Aug 2008 - Waterhammer - Part 1  What & Why

Sept 2008 - Waterhammer - Part 2  Causes & Variables                           Oct 2008 - Lower Flow Nonclogs - Solids Handling Options

Nov 2008 - Variable Speed Pump Selection - Part 1 Cp-Vf                       Dec 2008 - Variable Speed Pump Selection - Part 2 Vp-Vf

Jan 2009 - Variable Speed Pump Selection - Part 3 Vp-Vf (+Cp)              Feb 2009 - Resonant Frequency & Critical Speed

Mar 2009 - Specific Gravity & Viscosity - Part 1                                     April 2009 - Specific Gravity & Viscosity - Part 2

May 2009 - Variable Speed Performance Analyzer - 50hz                       June 2009 - Inertia - Confusing Units Revisited

July 2009 - Why The Left Can Be Dangerous                                          Aug 2009 - Planning for System Growth

Sept 2009 - PD Pump Hydraulics - Part 1 Reciprocating                           Oct 2009 - PD Pump Hydraulics - Part 2 Rotary

Nov 2009 - Corrosion - A Natural Process                                               Dec 2009 - Magnetic Couplings - Extra Benefits

Jan 2010 - Radial Thrust Calculator                                                        Feb 2010 - Suction Calculators

Mar 2010 - Energy Calculator                                                                 April 2010 - Cycle Time

May 2010 - BEBOP                                                                                  June 2010 - AC Power - Part 1

July 2010 - AC Power - Part 2                                                                 Aug 2010 - AC Power - Part 3

Sept 2010 - AC Power - Part 4                                                                 Oct 2010 - VFD Parallel Pump Analyzer

Nov  2010 - Coating & Restoration - Part 1                                                Dec  2010 - Coating & Restoration - Part 2

Jan 2011 - Variable Speed  Pump Analysis                                                Feb 2011 - Testing Pumps in the Field

Mar 2011 - AC Motors Part 1                                                                     April 2011 - AC Motors Part 2

May 2011 - AC Motors Part 3                                                                    June 2011 - AC Motors Part 4

July 2011 - AC Motors Part 5                                                                    Aug 2011 - AC Motor Torque

Sept 2011 - Switched Reluctance Motors                                                   Oct 2011 - Modeling & Design Software

Nov 2011 - Suction Specific Speed Revisited                                             Dec 2011 - Wastewater Drawdown Calculator

Jan 2012 - Off BEP Energy Calculator                                                       Feb 2012 - Centrifugal Pump Efficiency Part 1

Mar 2012 - Centrifugal Pump Efficiency Part 2                                          April 2012 - Centrifugal Pump Efficiency Part 3

May 2012 - Centrifugal Pump Efficiency Part 4                                          June 2012 - Centrifugal Pump Efficiency Part 5

July 2012 - Centrifugal Pump Efficiency Part 6                                          Aug 2012 - Bernoulli - Part 1

Sept 2012 - Bernoulli - Part 2                                                                     Oct 2012 - Velocity Head

Nov 2012 - Affinity Calculators                                                                  Dec 2012 - Learning

Jan 2013 - Volts per Hertz & VFD HP                                                         Feb 2013 - Branch Line Pumping Options Part 1

Mar 2013 - Branch Line Pumping Options Part 2                                          April 2013 - Three False Forces & One Real Force

May 2013 - Motor HP & Torque Versus VFD Frequency                               June 2013 - Wye / Delta Part 1

July 2013 - Wye / Delta Part 2                                                                  Aug 2013 - Wye / Delta Part 3

Sept 2013 - Breadth of Efficiency                                                             Oct 2013 - Dezincification

Nov 2013 - Wastewater Pump S Values                                                       Dec 2013 - Parallel Analyzer

Jan 2014 - Hydraulic Rams                                                                        Feb 2014 - The Cost of Pumping

Mar 2014 - AC Motor Efficiency                                                                April 2014 - Igor Karassik

May 2014 - Submersible WW Pump Testing Part 1                                       June 2014 - Submersible WW Pump Testing Part 2

July 2014 - Voltage Variation & Unbalance Part 1                                       Aug 2014 - Voltage Variation & Unbalance Part 2

Sept 2014 - Power Factor A Tale of Two Currents Part 1                            Oct 2014 - Power Factor A Tale of Two Currents Part 2

Nov 2014 - Power Factor A Tale of Two Currents Part 3                             Dec 2014 - Goodbye!!

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Other Publications - Joe Evans, Ph.D


The work I did prior to 1986 was quite different than what I do today.  I attended grad school (69 - 73) during an interesting era.  The advent of the minicomputer in the late 60's and early 70's allowed us to accomplish things that were impossible for those before us.  All of a sudden, data generated by scientific instruments (especially the gas chromatograph - mass spectrometer (GC-MS)) that used to take months to analyze provided results within days.  Back then the typical minicomputer was the size of a filing cabinet and had 2 - 4 K of memory.  Data storage was on paper tape or maybe mag tape if you were lucky.  It was still the time of the slide rule and analog recorders and just comparing the area under two plotted curves could take hours.  Much of our work on instrument automation was sponsored by NASA and the Robert A Welch Foundation. We were also chosen as one of the few labs to analyze the soil samples gathered by the first NASA Lunar Lander project.

In 1973 I entered the army as captain and chief of the Air Chemistry Branch of the Army Environmental Hygiene Agency.  This agency was the army's version of the EPA/NIH and its research was designed to protect our troops and reduce our impact on the environment.  One of our major projects at the time was monitoring the detoxification and disposal of our WWII nerve gas stock pile at Rocky Mountain Arsenal (which, by the way, was stored for decades right at the end of the main runway of the old Denver airport).  During my stay I continued my work on instrument automation and also the miniaturization of those instruments for use in the field.

After leaving the army in 1975 I joined Finnigan Corporation, a major GC-MS developer and manufacturer of the era.   I was in charge of the East Coast applications lab in Washington DC and later moved into the position of product manager.  By the mid 70's the minicomputer had advanced substantially and this technology gave us the ability analyze the data provided by a GC-MS in real time - - not days.

In 1977 I made the decision to move to Hawaii and, except for the University of Hawaii, there were no job opportunities that could make use of my past experience.  Hawaii is a major union state and unfortunately this spilled over to the university and I doubted that I would fit in well in that environment.  So, on a lark, I changed directions and took a position with IBM.  Oddly enough, my minicomputer experience paid off and over the next five years I worked in industrial automation as well as distributed processing in the business community.  One of our major accomplishments was the implementation of a on line directory assistance system at Hawaiian Telephone.  It was a distributed processing system that consisted of three layers of minicomputers and fixed head disk drives that could perform searches as deep as nine levels of indent in seconds.   The result was a directory assistance operator reduction of about two thirds which the union, of course, did not see this as a useful technological advance.  Although it was nowhere near the speed of Google, it was lightning fast for its day.

In 1983, the Queen's Medical Center (Hawaii's largest healthcare organization) offered me the position of VP of Information Services.  I learned early on that accepting this job was a mistake as I was unaware of the politics and in fighting that went on in these "non-profit" organizations.  Still, in less than three years we were able to take them to the forefront of the information age.  We were the first company in Hawaii to employ personal computers instead of dumb terminals and we had our own "intranet" email system in early '84.  Unfortunately continuing confrontations with the CEO (a psychiatrist who was having an affair with the head of nursing who had a striking resembalance to "Miss Piggy") led to my demise in late '85.

In 1986 I accidentally fell into the pump industry.  And, as most of you know, once you are in this industry it is hard to escape!  Below are several papers that I published or took part in prior to that fall.


Isolation and Partial Characterization of Supernatant and Mitochondrial Shrimp Muscle Malate Dehydrogenases


This paper, published in Comparative Biochemistry & Physiology (Pergamon Press), was a result of the research performed for my masters thesis.  It is co-authored by my advisor and two of my associates.  The work was sponsored by the National Institutes of Health and the Robert A Welch Foundation.

Program ELAL:  An Interactive Minicomputer Based Elemental Analysis of Low & Medium Resolution Mass Spectra


This paper, published in Analytical Chemistry (American Chemical Society), was a result of some of my doctorial research and follow on work done at the U.S. Army Environmental Hygene Agency.  The program was the first to computerize the manual elemental analysis methods developed by Dr. Fred McLafferty at Cornell University.

Monitoring Organic Vapors

This paper, published in  Environmental Science & Technology (American Chemical Society), was a result of my continuing work at the U.S. Army Environmental Hygene Agency.  It discusses the ongoing micro-computerization and miniaturization of environmental monitoring instruments.  It was co-authored by Jim Arnold of Varian Associates, a physicist and major contributor to technology advances in mass spectrometry and nuclear magnetic resonance (NMR) spectrometry (now known as magnetic resonance imaging (MRI) due to our ignorance and fear of that other "n" word).  The mass spectrometer described in this paper was the predecessor of the one that was aboard the Mars Lander.

User Written Software Extends the Use of GC-MS Data Systems

Published in Finnigan Spectra (Finnigan Corporation), this article revisits the use of Program ELAL and introduces a new program known as FINL (fragment ion and neutral loss analysis).  FINL automated another manual elemental analysis methodology that was developed by McLafferty at Cornell University.

INFO

In 1983 I left IBM and assumed the position of VP of Information Services at The Queen's Medical Center in Honolulu.  One of the first things that we did was to initiate a news letter to keep the employees of our almost 150 departments up to date on what we were doing.  This is the first issue.

The Queen's Medical Center - - A Royal Link to the Past and the Future

In late '83 we entered into an agreement with Management Science America (MSA) to install their GL, AP, and Payroll/Personnel systems and their "Peachpak" interactive PC products.  This article highlights our accomplishments over a period of just one year.

OA Reigns Supreme at Queen's Medical Center

In 1985, "Today's Office" (Hearst Business Publications) selected Queen's as one of the nation's leader's in office automation and asked me to write an article outlining what we had done to get there.  This was my last non-pump article!

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Education Links
If you have suggestions for additional educational links, please e-mail me at
joeeevans@gmail.com

Pump Fundamentals - Lots of Good Pump & Pump System Info
http://www.pumpfundamentals.com

 
FreeCalc.Com - Lots of Good Online Calculators
http://www.freecalc.com
 
All About Circuits - AC, DC, and Much More
http://www.allaboutcircuits.com/vol_2/index.html

Integrated Publishing - Electrical Engineering Training Series
http://www.tpub.com/content/neets/
 
The Engineering Tool Box - Pump Information & Calculators
http://www.engineeringtoolbox.com/

Light & Matter - Free Physics Text Books
http://www.lightandmatter.com/

Pump School -
A Rotary Pump Course
 www.pumpschool.com/

Cheresources - Chemical Engineering Resource
http://www.cheresources.com/indexzz.shtml

Math and Physics Help - Simplifying Math & Physics by Kenny Felder
www.ncsu.edu/felder-public/kenny/home.html

  Motion Mountain- Free Physics Text Book
http://www.motionmountain.net/

  Applied Flow Technology - Free Pump System Modeling Software
http://www.aft.com/products/PSIM.php

University of Michigan - PID Tutorial
http://www.engin.umich.edu/group/ctm/PID/PID.html


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Pump Calcs

Pump Calcs is a web site that offers a number of very useful calculators and conversion utilities.  It is sponsored by Pumps & Systems magazine.

http://www.pumpcalcs.com


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Your Hawaiian Retreat

My nephew Hugh and his wife Elvira own and operate a very different vacation rental outside Puna, on the Big Island of Hawaii, just 25 miles north of the Volcanos National Park.  It offers ocean views in a truly rual environment.  In this area of the island, lava pools and black sand beaches rim the coast but just a few yards inland it becomes a beautiful forest.  They have several different units that can accomodate from two to fifteen people and will even provide three meals a day if you wish.  The rates - - outrageously inexpensive!  The picture below is of the Ohana House.  For more information and a tour of the grounds, click on their web site link below.



http://www.yourhawaiianretreat.org


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Robert Perez has worked in the petrochemical Industry
for 30 years.  He has written many papers on rotating
equipment and also taught the Rotating Equipment course
at Texas A & M University.  His new book was written
specifically for those who are responsible for the
operation and maintenance of centrifugal pumps. Click on
the link below to review the topics covered.

http://www.noria.com/secure/product_detail.asp?catalogid=149

You can also purchase the book at Amazon.com, Barnes and Noble, etc.,
or contact Mr. Perez directly at rxperez@pumpcalcs.com for quantity
discount orders.




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PumpTech, Inc. Newsletter - - PumpTech Pipeline

In 2010, I began a quarterly newsletter for my employer PumpTech.  Pdf versions are available below.  In addition to featuring our products and packaged systems, it also has lots of pump related info.  If you use full screen mode in Acrobat you can use the page links to move through the document.  If you would like to subscribe to the email version, click on the email link below and send us your name, company and preferred email address.

Check out PumpTech at: http://www.PumpTechnw.com  or sign up for the email newsletter at:  newsletter@PumpTechnw.com

Spring 2010            Summer 2010           
Fall 2010            Winter 2011        Spring 2011        Summer 2011         Fall 2011        Winter 2012

Spring 2012               Summer 2012               Fall 2012           Winter 2013        Summer 2013      Winter (Feb) 2014

Winter (Dec) 2014


Chick on the links below to download the brochures & data sheets for several PumpTech packaged systems.

iRover   Wet Well Retrofit   Vacuum Assist   Hydronix Brochure   MeterMan Brochure   PolyMan


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SALINITY LLC - Gourmet herb and spice infused finishing salts handcrafted in Southern Oregon

My stepdaughter, Laine, and her friend Jody own a very unique business down in Grants Pass Oregon.  They handcraft the most delicious finishing salts that I have ever tasted.  They combine the finest grey sea salt with organically grown herbs and spices to create a unique end to any of your favorite dishes.  The herbs and spices are all grown locally with one exception.  The ginger comes from my nephew Hugh's organic ginger farm on the Big Island of Hawaii !  Click on the link below to learn more and order online.

                           

http://www.salinitysalts.com


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