Pump Piping, Components and their Arrangement
<<This article describes the process piping design with emphasis on components of piping installed on a typical centrifugal pump. >>Pump Suction Design
<<The design of a piping system can have an important effect on the successful operation of a centrifugal pump. Such items as sump design, suction piping design, suction and discharge pipe size, and pipe supports must all be carefully considered.>>Pump Alignment and Installation
S.A. Armstrong Limited
<<The following text and illustrations are offered as general suggestions for the preparation of a satisfactory foundation.>>Centrifugal Pump System Tutorial
Fluide Design Inc.Friction in a Pump System
Fluide Design Inc.
<<Another cause of friction is all the fittings (elbows, tees, y's, etc) required to get the fluid from point A to B. Each one has a particular effect on the fluid streamlines. For example in the case of the elbow, the fluid particles that are closest to the tight inner radius of the elbow lift off from the pipe surface forming small vortexes that consume energy. This energy loss is small for one elbow but if you have several elbows and other fittings they can become significant. Generally speaking they rarely represent more then 30% of the total friction due to the overall pipe length.>>Influence of Specific Gravity on Total Head
Fluide Design Inc.
<<The pump performance or characteristic curve is often referred to as a water performance curve (see Figure 1). Water is naturally the fluid of choice for testing pumps because of its availability. The question is: can the water performance curve be used for other fluids? The answer is yes with care.>>Concept of Cavitation
<<Cavitation is a common occurrence but is the least understood of all pumping problems. Cavitation means different things to different people. Some say when a pump makes a rattling or knocking sound along with vibrations, it is cavitating. Some call it slippage as the pump discharge pressure slips and flow becomes erratic. When cavitating, the pump not only fails to serve its basic purpose of pumping the liquid but also may experience internal damage, leakage from the seal and casing, bearing failure, etc. In summary, cavitation is an abnormal condition that can result in loss of production, equipment damage and worst of all, personnel injury.>>Testing and Maintenance of Fire Pumps
<<Fire pumps are perhaps the most critical single piece of fire protection equipment installed at a site. Just like people, fire pumps come in all shapes and sizes. Fire pumps are needed at sites where public water supply pressure is too low for sprinkler effectiveness or where there is no public water supply at all. In the former case, a booster fire pump is installed to boost public water pressure to increase sprinkler effectiveness. In the latter case, a fire pump is connected to a private water supply (storage tank, reservoir, lake, river, or other) to create water pressure needed for sprinkler effectiveness and fire-fighting efforts. Most fire pumps are either diesel engine driven or electric motor driven; however, some of those manufactured before 1974 are gasoline engine powered or even steam engine driven (though this is very rare). Booster fire pumps are usually electric pumps, whereas diesel fire pumps are more common on private water supplies. >>Rotary Pump Startups [PDF]
Warren Pumps Inc.
<<Many pump startups are the culmination of months if not years of work designing the process, machine or system, specifying components, instrumentation, protective devices, and reviewing and qualifying suppliers. It is also the most vulnerable time for any pump. This article describes cautions, reviews and inspections that should be conducted before startup to help insure that all those many gremlins of pumping systems are found out and eliminated in time. >>Pump Care Manual
<<All subjects covered, whether written or illustrated, are suggestions by Berkeley Pumps to aid in the proper installation and operation of end suction centrifugal pumps and apply to no particular application.>>Machinery Grouting
M&M Precision Grouting
<<Grout has to be used in conjunction with a properly torqued anchor bolt system when both static and dynamic loading is involved, such as with compressors, turbines, pumps, gear boxes and most heavy industrial machines. It takes both good grout and good bolts to properly hold the modern machines industry uses today.>>Pump Basics
Plant Engineering Magazine
<<Pumps are one of the oldest machines used by man for transporting energy from one form to another. It is not surprising that the there are many designs, resulting in some confusion when generic identification of a specific pump is attempted. The simplest way to classify pumps is based on the method used to transmit power to the pumped liquid, mechanical principle behind this energy transfer, and mechanical device for moving fluid. These considerations result in two major pump classes: kinetic (dynamic) and positive displacement.>>Pump Installation "To do" Lists
Plant Engineering Magazine
<<A process engineer has selected a pump, chosen a vendor, and placed the equipment on order. The project engineer begins managing the installation details. As he contemplates the remaining items required, he realizes that a variety of design activities lie ahead and a "To Do" list must be prepared.>>Advantages of Parallel Pumping
Plant Engineering Magazine
<<It is generally true that the larger the fluid flow requirement, the more viable parallel pumping can be. However, parallel pumping can be successfully applied to both large and small systems.>>How Does Pump Suction Limit the Flow?
<<One of the claimed advantages of the centrifugal pumps over positive displacement pumps is their ability to operate over a wide range of flow. Since a centrifugal pump operates at the intersection of a pump curve and a system curve, by varying the system curve the operating point of the pump is easily changed.>>Relief Valves for PD Pumps - Internal or External?
<<Positive Displacement pumps are knows as "flow generators", while centrifugal pumps can be thought as pressure (or head) generators. It is easy and convenient to control the centrifugal pump with a discharge valve: it changes a system curve, resulting in pump operating at different flows (see Article "How does pump suction limit the flow?"). Not so for the positive displacement pumps. All types of a PD pump (piston, rotary gear, lobe, vane, etc.) have a major similarity, which distinguishes them from the centrifugal pumps: PD pump curves show that they produce almost (depending on viscosity and internal clearances) the same flow, regardless of the differential pressure.>>Pump Out Vanes
<<The main reason to use pump-out vanes (POV) is to change the pump axial hydraulic thrust. The rotation of the impeller results in “dragging into rotation” of the fluid in the gap between the impeller and casing walls. This is similar to a motion of a teaspoon in a cup, or a disk spinning inside containment. The resulting motion is referred to as “forced vortex”.>>Free online pump selection software
<<Select from leading manufacturers' online catalog.>>Controlling Centrifugal Pumps
<<The centrifugal pump is one of the simplest pieces of equipment from the controls and instrumentation point of view. It is a two port device with a well defined characteristic. Its purpose is to provide the necessary pressure to move liquid at the desired rate from point A to point B of the process. Figure 1-1 shows a 'generic' process with a centrifugal pump connected to deliver liquid from A to B.>>Controlling Positive Displacement Pumps
<<There is a great variety of positive displacement pumps. They are divided into two broad categories: Rotary and reciprocating. From the controls point of view, however, they are all similar. Their characteristic curve is so simple that it is rarely drawn. It is essentially a straight vertical line, as shown in Figure 2-2. (For some reason PD pump curves are usually shown with the pressure and flow axis exchanged. I will not follow that convention in this article.) All are constant flow machines whose pressure rises to whatever value is necessary to put out the flow appropriate to the pump speed. If the discharge is blocked, the pressure will rise until something yields -- preferably a relief valve. Close examination of the curve shows a slight counter clockwise rotation. This is due to internal leakage.>>A Challenge Like No Other: Pumping Under the WTC Devastation
Thompson Pump & Manufacturing Co., Inc.
<<The goal of this on-line magazine is to provide a technical resource to the pumping community on a variety of subjects, relating to pump operation, design, maintenance and reliability, latest technologies, field case study examples, and the exchange of ideas - within a wide spectrum of pump topics. This is why the topics covered in PUMP MAGAZINE are, first of all - technical, and secondly, specific and focused on a given subject, or issue, as related to pumps. The objective is for users to find answers to their questions, and, more importantly be able to post questions, should the answers not be readily available. Such interactive and technically focused approach to pumps, we believe, provides the pump users what they really need - the answers to their questions, un-biased, and to the point. This technical and user-oriented approach is the specialty of the PUMP MAGAZINE. >>Online Pump Selector
Impeller.netDouble-Suction Pump in Cooling Water Application
Chemical Processing Magazine
<<Pumping applications involving cooling water have been especially difficult to solve because of the presence of dissolved air inherent in a cooling tower sump. Water that contains large amounts of dissolved air changes the apparent required net positive suction head (NPSH). In such applications, traditional correction techniques failed because the entire system was not analyzed and the source of the noise generation could not be pinpointed. This article explains the steps taken to solve this type of problem for Dow Chemical's plant in Freeport, TX, through computational fluid dynamics (CFD) and recounts the results.>>Pump Technology Before The Electric Motor [OFFLINE]
<<Before electric power was common-the turn of the century in most major cities, but not very long ago in many other parts of this country-water still needed to be moved. Sometimes it needed to be moved great distances, but sometimes only a small lift. Many applications were suited to gasoline powered pumps, but the gas engine only became available in the 1860s (steam engines being available a little before that). For many applications where neither option was practical (low flow applications; remote or unattended sites; areas where the cost of fuel for continuous duty applications was high; or areas where the initial cost of an engine and frame mounted pump could not be justified) other arrangements were needed.>>Pump Fundamentals (PDF Documents)
<<Centrifugal Pump Fundamentals, Pump Application Guide, Water Data, Properties of Liquids, Paper Stock, Mechanical Data, Motor Data, Conversion Factors & Engineering Data, Pump Operation & Maintenance, Miscellaneous Pump Information.>>Pump FAQs
<<How do I read a pump curve? How do centrifugal pumps work? Which type of tank should I use? How do I determine the energy consumption of a pump? Why should I care about suction lift? What is the purpose of a torque arrestor? Do I need a snifter valve, bleeder orifice or air release valve? Should I worry about below freezing temperatures? Why do submersible pumps fail? >>Select A Positive Displacement Pump In 10 Steps [OFFLINE?]
Viking Pump, Inc.
<<The following article is an abbreviated version of Viking Pump's PD pump selection process and discusses how and why certain application data is utilized during the selection process. The specific mathematical calculations for each step are beyond the scope of this overview but warrant discussion in future articles -- in fact, each step of the process contains enough information to be an article unto itself. And although this is the Viking Pump selection process, the basic steps and data requirements are similar for all PD pump manufacturers.>>Cheng Rotation Vane
Cheng Fluid Systems
<<The Cheng Rotation Vane (CRV® ) consists of a set of stationary vanes in a cylindrical body which is placed immediately upstream of an elbow or tee in a piping system. The CRV® eliminates elbow induced turbulence which negatively impacts the performance of pumps, compressors, flow meters, and other equipment. The CRV® inputs to the flow a counteracting gyroscopic motion to the resultant elbow induced gyroscopic motion, and enables the fluid to negotiate the turn through the elbow and then exit the elbow with a flat velocity profile. This results in an even distribution of process fluid through any cross-section of the elbow and transforms the elbow into the equivalent of a straight section of pipe. >>Large Angle Diffuser
Cheng Fluid Systems
<<The Large Angle Diffuser (LAD® ) ensures an even flow distribution in sudden expansions which occur ahead of the heat exchangers, boilers, condensors, and blow down systems. Without a LAD® long pipe runs or elaborate custom engineered baffles that consume pressure drop are required. The LAD® consists of a series of overlapping truncated cones, with a common focal point, that is located within the expansion. Despite a sudden increase in pipe diameter, the LAD® produces a flat velocity flow profile, that results in an even distribution of the process fluid during the concentric expansion. Using a LAD® avoids the limiting expansion of 15o between the expanding pipe diameters. >>Pump Selection
The Pump Centre
<<Pump selection is regarded by many engineers as a black art and they are only too happy to pass on as much of this task as possible to the prospective pump supplier or manufacturer. Using a manufacturer that has vast experience of pumps and undertakes similar selection procedures on a daily basis is a sensible strategy for saving valuable time and money. The major strength or weakness of this selection partnership is "communication" - making sure the manufacturer knows exactly what the pump is expected to do. For successful pump selection purchasing engineers must be clear in their own mind what they want and why they want it. They must complete a specification document including a suitable data sheet and system drawings. It is important that they have a good feel for what generic type of pump they require so that approaches are made to manufacturers who have suitable products to offer. Also they must be able to assess the relative merits of competitive bids from different suppliers. The needs and characteristics of the pumping system determine what pumps can be used. The guidelines given below address the issues that every engineer should consider before purchasing a pump. >>Pumps Galore! Dispelling Some Centrifugal Pump Fallacies
<<The field of centrifugal pump design and application is a specialized one. It has its own set of terminology that, if not completely understood by a designer, can affect the performance of a centrifugal pump installation. Complete familiarity of this vocabulary as well as a solid working knowledge of fluid dynamics and pump design is essential to being a member of the pumpology clergy. To narrow the scope here, let's consider water at 70 degrees F at sea level. To approach some centrifugal pump fundamentals, let's consider a few common myths:>>Well Pumps
General Dennis J. Reimer Training and Doctrine Digital LibraryHistory of the Disc Pump
Advanced Fluid Technologies
<<The disc pump concept dates back to 1850. A pump was invented in the US by Sargent, who took a series of 29 parallel discs spaced a few thousands of an inch apart, enclosed them with a metal band, and made a number of holes in the band to allow fluid to pass in and out (see Figure 1). It was the first example of a pump operating solely on the boundary layer/viscous drag principle.> >Cavitation Home Page
University of Texas at AustinRules of Thumb for Pumps
The Mc Nally InstitutePump and Process Protection
Process and Industrial Training Technologies
<<Positive displacement pumps deliver a given volume of fluid based on speed regardless of system pressure (disregarding slip). As process flow is decreased the pressure developed is increased and the flow from the pump must be directed elsewhere to avoid over pressurization. To protect the pump and system the fluid must be by-passed to another destination, or relieved within the pump itself from the higher pressure discharge side to low pressure suction.> >Pumping High Temperature Liquids
<<High-temperature applications are becoming more prevalent in the fluid handling industry. Consider an application to be high temperature when the operating temperature is above 110 degrees C / 225 degrees F. Pumps intended for use at ambient temperatures are not recommended for use at high temperatures without some modifications.In fact, if an engineer does not take into account some of the problems that can result from using a standard or "stock" pump on a high temperature application, a variety of consequences may result -- from leaky gaskets and stalled drives to broken pumps and shattered casings.> >Pump Cavitation
The Mc Nally Institute
<<Cavitation means that cavities are forming in the liquid that we are pumping. When these cavities form at the suction of the pump several things happen all at once. The cavities form for four basic reasons and it is common practice to lump all of them into the general classification of cavitation. This is an error because we will learn that to correct each of these conditions we must understand why they occur and how to fix them.> >Pump Cavitation - What Causes the Noise and Damage?
The Mc Nally InstituteWhat You Should Know about Piping Systems
The Mc Nally InstituteCentrifugal Pump Installation
The Mc Nally InstitutePump Grouting
The Mc Nally InstituteComputational Fluid Dynamics Analysis Solves Pump Noise Problem
Chemical Processing Magazine
<<Pumping applications involving cooling water have been especially difficult to solve because of the presence of dissolved air inherent in a cooling tower sump. Water that contains large amounts of dissolved air changes the apparent required net positive suction head (NPSH). In such applications, traditional correction techniques failed because the entire system was not analyzed and the source of the noise generation could not be pinpointed. This article explains the steps taken to solve this type of problem for Dow Chemical's plant in Freeport, TX, through computational fluid dynamics (CFD) and recounts the results.> >NPSH (Net Positive Suction Head) Calculation(s)
Henning, Metz, Hartford and Associates, Inc.
<<A pump is a device that expends energy to raise, transport, or compress fluids--liquids and gases. The term pump is generally used for liquid-handling or hand-operated devices, while the term compressor is used when the pressure of a gas is increased in a motor-driven machine.> >Fire Pump Systems-Design and Specification [OFFLINE]
<<Point of view is everything when discussing fire pump systems. For the engineering-contractor, they are relatively uncommon systems referencing specifications unheard of in conventional process units. To the purchaser, they are mandated systems that take time, space and capital away from money-making units. For users, fire pump systems are (or should be) a once a week test requirement. But in spite of the time, space and money constraints, fire pump systems must work as required. Period. Hundreds of lives and millions of dollars in hardware and production costs rely on the performance of these systems. Fortunately, they almost always work. Because of the critical nature of this service, one might think that industry standards could simply be invoked to insure reliable design and specification. Of course they can. They just never are. At least not without the addition of supplemental proprietary specifications that can conflict with industry standards, government regulations and sometimes with the basic system design. Seemingly minor requirements can result in the loss of a listing agency label and render a perfectly functional system unacceptable to insurers or governmental agencies.> >Piping-to-Pump Alignment: Getting It Right! [OFFLINE]
<<In theory, hardly anyone would disagree that proper piping alignment is crucial to pump operation. In a nutshell, piping should be designed and installed in such a way that no loads are transmitted to the pump. An unstressed pump is a happy pump. Most of us have heard the term "free bolt condition". The bolts that connect the suction and discharge pipe flanges to a pump should just "drop in", with no forcing effort applied. If the free-bolt-condition rule is violated, bad things are guaranteed to start happening. A pump structure is flexible, no matter how tough its casing is designed. It does not take much pipe-to-pump misalignment to distort the casing and warp the pump, flanges, feet, seal faces and coupling. The laws of physics are unforgiving.> >"Creating Pump Standards Since 1917"
Hydraulic InstitutePump Intakes / Pump Suction Piping
Richard Neff Irrigation Craft Corporation
<<Designing Intake Lines, Installing Intake Lines, Diagnosing and Repairing Intake Lines, Pump Cavitation In Depth> >Understanding Pump Cavitation
<<Cavitation is a major problem in the chemical industry because it affects a basic tool, the centrifugal pump. A sudden increase in the velocity of the pumped liquid reduces the inlet pressure, sometimes below the vapor pressure.The result is formation of gas and bubbles. Detecting the signs of cavitation, and correctly identifying and understanding the type of cavitation present, can help an operator prevent serious damage.> >Fluidedesign.com
Help to solve your fluid transfer problems
<<This site is designed to help you solve your fluid transfer problems. You will find all the information you need to design your pumping system and select the right pump for the job.> >Pumps - Directory.com
More than 5000 Links to pump manufacturers world-widePumpWorld.com
Educational Site, Contains Tutorials
<<Pump Terms, Pump Operation, How to read Pump Curves, How to Calculate Total Dynamic Head, How to Calculate System Head Curves, NPSH, Cavitation, Parallel Pump Operation, Pumps in Series, Pumping Viscous Liquids, Charts> >Troubleshoot Pumps Using Pump Curves and Gauge Readings
Contracting Business Magazine
<<A manufacturer's pump performance curves contain data that can help hvac technicians analyze a pumping instal-lation. Pump curves also help identify the system's operating point, find reasons for a system not performing, and even determine a pump's impeller size. After designing a pump, the manufacturer usually produces a number of units for testing. The tests are necessary to establish how the pump will perform. The data collected often includes water flow operating against various system resistances, brake horsepower required, efficiency, and the net positive suction head required for proper operation of the various diameter impellers allowable in the pump volute.> >A Working Man's Guide to Servicing Centrifugal Pumps
<<A pump is a wonderful thing when operating properly. You never give it a second thought. But when it's not running properly, you hear about it right away. People on the receiving end are not getting heat, cooling, process fluids, etc., and they're quick to let you know, usually very loudly. So here are some service procedures for centrifugal pumps that will help keep your customers in hot water and you out of it.>>The Mystery of Cooling Tower Pump Noise
<<The problem of "cavitating condenser water pumps" with adequate NPSH available is not uncommon. We discussed this phenomenon with cooling tower manufacturers and other centrifugal pump designer/manufacturer members of the Hydraulic Institute. All agree that this phenomenon commonly concerns cooling tower applications. We see on average one or two such cases per year. At this point, several theories are offered to explain the cavitation-like noise, but none validated.>>Armstrong Pump FAQ
S. A. Armstrong LimitedSuggested Piping Layout For PROCON Pumps
A Pump Engineer's Toolbox of InformationNPSH: Net Positive Suction Head
The Mc Nally InstitutePump Troubleshooting, Very Comprehensive
<<There are a number of complex equations that deal with water pump engineering. Although not difficult to work with pen and paper, they can be time-consuming. This page eliminates much of the labor. Simply "plug in" your values in the blanks and press the "Calculate" button. The results will be computed for you. Best of all, if the answer is used as a variable in another equation, it will automatically be placed in any other such equation, allowing for rapid calculation of pump technical data.> >Pump Protection
Process and Industrial Training Technologies
<<Positive displacement pumps deliver a given volume of fluid based on speed regardless of system pressure (disregarding slip). As process flow is decreased the pressure developed is increased and the flow from the pump must be directed elsewhere to avoid over pressurization. To protect the pump and system the fluid must be by-passed to another destination, or relieved within the pump itself from the higher pressure discharge side to low pressure suction.> >General Pump FAQs
Cole-Parmer Instrument CompanyPressure Drop / Flowrate Calculator
By Paul SeamonsWaterhammer : A Complex Phenomenon with a Simple Solution
Omega Engineering, Inc.
<<Waterhammer is an impact load that is the most misunderstood force known to pressure transducers today. A waterhammer is created by stopping and/or starting a liquid flow suddenly. The results of a waterhammer or impulse load are devastating to a pressure sensor. The impulse load occurs suddenly, in the millisecond time frame, but the effects of it last a life time. Waterhammers occur in almost all pressure systems and usually can not be stopped without extensive time, energy and studies.> >