Pump Selection Handbook

8/10/2019 Pump Selection Handbook

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PumpSelectionHandbook


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Lets Talk About PumpsHow many pumps do you own? Its actually a very interestingquestion. If you asked a contractor or rental store operator theymight respond with a number anywhere between 1 and 50. Onthe other hand a layperson might reply that he has no need forpumps in his home or workplace. So, getting back to our originalquestion, how many pumps do you own?

Even if you think you dont own any, the chances are very good

that you own a few pumps and simply forgot to consider them.Pumps are among the most widely manufactured items in theworld and their many designs permit their use in a variety ofapplications. They are used in everything from washing machines,refrigerators, cars and trucks to construction sites, wastewatertreatment facilities and food-processing plants.

Pumps make possible many everyday tasks that we often takefor granted. Indeed without pumps our world would be a much

different place than we know it today.

Pumps & The Contractor

As noted previously, there are many types of pumps available intodays market. Yet there is not one pump ideally suited for everyapplication. Since Multiquip primarily targets the constructionindustry our pumps are engineered to meet the requirements ofthe professional contractor.

Construction is a competitive business with deadlines andbudgets that contractors have to meet in order to be successful.A heavy storm can set a job back several days or even weeks.Prolonged downtime can cost contractors substantial amountsof money since bonuses are often paid for finishing jobs underbudget and ahead of schedule. Ask a contractor this question,What do you expect out of a water pump? and the answers will

likely be along these lines:

Performance the ability to quickly move a high volume ofwater

Low Downtime the ability to pass debris withoutclogging

Durability the abil ity to withstand harsh workenvironments

Value all of the above features at an economical price

Centrifugal. High-pressure. Trash. Submersible. Diaphragm.Self-priming. Zero-prime. With so many types of pumps availableto contractors, how can you be sure what to recommend fora specific application? Once you become familiar with thecharacteristics of the most common rental pumps its actuallyeasier than you might think.

Common Water Pump DesignsWhile many pumps can be found on job sites there are twovery general types of water pumps in the construction industry.Different in design and application they each basically serve the

same purpose, which is to move water from point A to point B.

The first type of pump is the centrifugaldesign. This type uses arotating impeller to draw water into the pump and pressurize thedischarge flow. Common rental pumps include standard, trashand submersible models.

The second type of pump is the positive displacementdesign,the most common of which is the diaphragm type. These pumpsdeliver a fixed amount of flow per cycle through the mechanicalcontraction and expansion of a flexible diaphragm.

These pumps will be covered in greater detail later after reviewingsome basic pump theory.

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Figure 1

The Basics Of Pump TheoryIt is common for customers to say they need a pump to suckwater out of a hole or trench. However, centrifugal and diaphragmpumps do not actually suck water so much as they raise or lift itwith help from mother nature.

Water, like electricity, will always flow along the path of leastresistance. In order to liftwater the pump must provide a path(area of low pressure) to which water will naturally seek to flow.

It is critical then to recognize the role atmospheric pressureplays in creatingsuction lift. At sea level the atmosphere exertsa force of 14.7 lb/in2(PSI) on the earths surface. The weight ofthe atmosphere on a body of water will prevent lift from occurringunless vacuum is created.

Figure 1shows three hollow tubes, each with a surface area of1-square inch, rising from sea level up into the atmosphere. Intube (A) atmospheric pressure is the same inside the tube as itis outside: 14.7 PSI. Since the weight of the atmosphere is beingexerted equally across the surface, no change occurs in the waterlevel inside the tube.

In tube (B) a perfect vacuum is created making atmosphericpressure greater on the water outside the tube. The resultingdifferential causes water, flowing naturally to the area of lowestpressure to begin filling the tube until it reaches a height of33.9-feet.

Why is 33.9-feet the highest water can be lifted in this example?Because at this point the weight of the water inside the tube exertsa pressure equal to the weight of the atmosphere pushing downon the oceans surface. This height represents the maximum

theoretical suction liftand can be verified using the followingcalculation.

Divide atmospheric pressure at sea level by .0361 lb/in3 (theweight of one cubic inch of water) to obtain the theoreticasuction lift.

14.7 (lb/in) .0361 (lb/in3) = 407.28 (in)

407.28 (in) (12 in/foot) = 33.9 (ft)

Remember that 33.9-feet is the maximum theoretical heighwater can be lifted under perfect conditions at sea level. It doesnot take into consideration altitude, friction loss, temperaturesuspended particles or the inability to create a perfect vacuum. Athese variables affect pump performance and reduce theoreticasuction lift. The practical suction lift, attainable for cold wate(60F) at sea level by creating a partialvacuum, is the 25-feereflected in tube (C).

Centrifugal DesignsThe overwhelming majority of contractor pumps use centrifuga

force to move water. Centrifugal forceis defined as the actionthat causes something, in this case water, to move away fromits center of rotation.

All centrifugal pumps use an impeller and volute to create thepartial vacuum and discharge pressure necessary to move watethrough the casing. The impeller and volute form the heart of apump and help determine its flow, pressure and solid handlingcapability.

An impelleris a rotating disk with a set of vanes coupled to theengine/motor shaft that producescentrifugal force within the pumpcasing. A volute is the stationaryhousing in which the impeller rotatesthat collects, discharges and recirculates water entering the pumpA diffuseris used on high-pressurepumps and is similar to a volutebut more compact in design. Manytypes of material can be used in theimanufacture but cast iron is moscommonly used for constructionapplications.

In order for a centrifugal, or self

priming, pump to attain its initiaprime the casing must first bemanually primed or filled with waterAfterwards, unless it is run dryor drained, a sufficient amount owater should remain in the pump toensure quick priming the next timeit is needed.

As the impeller churns the wate(Figure 2), it purges air from thecasing creating an area of lowpressure, or partial vacuum, at the


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eye (center) of the impeller. The weight of the atmosphere on theexternal body of water pushes water rapidly though the hose andpump casing toward the eye of the impeller.

Centrifugal force created by the rotating impeller pushes wateraway from the eye, where pressure is lowest, to the vane tipswhere pressure is the highest. The velocity of the rotating vanespressurizes the water forced through the volute and dischargedfrom the pump.

If The Pump Is Self-PrimingWhy Do I Need To Add Water?Most centrifugal pumps require the pump casing to be filled withwater (manually primed) before starting. Self-priming is a termused to generally describe many centrifugal pumps. This simplymeans the needs water added to the casing in order to create apartial vacuum to remove the air from the suction hose and pump

casing allowing water to flow freely into the pump.

There are many high-end pumps on the market that do notneed to be manually primed before operation. These pumps aregenerally referred to as Prime-assist pumps. They use a vacuumpump or an air compressor to remove the air out of the suctionhose and pump body in order to prime the pump. This enablesthe pump to start dry and re-prime itself without manually addingwater. In addition, these pumps can be used when lots of air hasto be moved such as with well point dewatering systems.

Water passing through the pump brings with it solids and otherabrasive material that will gradually wear down the impeller or

volute. This wear can increase the distance between the impellerand the volute resulting in decreased flows, heads and longerpriming times. Periodic inspection and maintenance is necessaryto keep pumps running like new.

Another key component of the pump is its mechanical seal. Thisspring-loaded component consists of two faces, one stationaryand another rotating, and is located on the engine shaft betweenthe impeller and rear casing (Figure 3). It is designed to preventwater from seeping into and damaging the engine. Pumpsdesigned for work in harsh environments will require a seal thatis more abrasion resistant.

Figure 2

Typically seals are cooled by water as it passes through the pump.If the pump is dry or has insufficient water for priming it coulddamage the mechanical seal. Oil-lubricated and occasionallygrease-lubricated seals are available on some pumps that providepositive lubrication in the event the pump is run without water.The seal is a common wear part that should also be periodicallyinspected.

Regardless of whether the application calls for a standard, high-pressure, or trash, every centrifugal pump lifts and dischargeswater in the same way. The following section will point out designdifferences between these pumps.

Standard Centrifugal PumpsStandard centrifugal pumps provide an economical choicefor general purpose dewatering. A number of different sizes areavailable but the most common model offerings are in the 2 to4-inch range with flows from 142 to 500 gallons per minute (GPM)and heads in the range of 90 to 115 feet.

These pumps should only be used in clear water applications

(agricultural, industrial, residential) as they have a limited solidhandling capability of only 10% by volume. The impellers typicallyuse a three-vane design (Figure 4A), and the volute(Figure 4D)is compact, preventing the passage of large solids. The rule ofthumb is the pump will only pass spherical solids the diameterof the suction inlet.

One advantage these pumps have over comparably sized trashmodels is their low initial cost. There are several reasons for thisdifference. Lower horsepower engines are utilized that are smallerin size and more fuel-efficient. The mechanical seals, since theyare not subjected to harsh working conditions, can be made ofless costly material. Additionally, the casings are smaller and

have fewer machined parts that when combined with the smallerengines make the pumps much lighter in weight.

High-pressure CentrifugalPumpsHigh-pressure centrifugal pumps are designed for use inapplications requiring high-discharge pressures and low flows.Contractors may use them to wash down equipment on the jobsite as well as install them on water trailers. Other uses includeirrigation and as emergency standby pumps for firefightingapplications.

Figure 3


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Typically these pumps will discharge around 145 GPM andproduce heads in excess of 300 feet. The pump may have a 2- or3-inch suction port and up to three discharge ports of varyingsize for added versatil ity. The impellers used on these pumps area closed design (Figure 4C)and not open like those used onother types of centrifugal pumps. Similarly the diffuser (Figure4F)is more compact than a regular volute in order to generatethe high discharge pressures.

These pumps by design are not capable of handling any typesof solids or even sandy water. Silt, sand or debris would almostimmediately clog the pump if allowed to enter into the casing.Additionally, the impeller and diffuser may be made of aluminumrather than wear-resistant cast iron since they are not subject toabrasive materials. It is recommended that a mesh net alwaysbe placed over the suction strainer if the pump is being used indirty water.

Trash Centrifugal PumpsTrash centrifugal pumpsget their name from their ability tohandle large amounts of debris and are the preferred choice of

contractors and the rental industry. The most common sizes arein the 2 to 6-inch range producing flows from 200 to 1,600 GPMand heads up to 150-feet.

The rule of thumb is that a trash pump will generally handlespherical solids up to the diameter of the suction inlet. Solids(sticks, stones and debris) flow through without clogging makingthem ideal for the water conditions typically found on job sites.Trash pumps handle up to 25% suspended solids by volume.

Trash pumps offer another benefit in that they can be quickly andeasily disassembled for service or inspection. While standardpumps require special tools that arent always available the insideof a trash pump housing can be accessed with common tools.

Customers occasionally ask why a trash pump costs morethan standard centrifugal pumps. One big reason is that higher

Figure 4

IMPELLERS

VOLUTES

CENTRIFUGAL TRASH HIGH PRESSURE

A B C

D E F

horsepower engines are needed for trash pumps. The impelleis a cast iron two-vane design (Figure 4B)and a large volute(Figure 4E) is required to handle the higher volume of water anddebris. The mechanical seal like the impeller and volute isselected for its abrasion resistance and more parts are machinedfor the casing. While there is a higher initial cost it must be notedthat this is recovered through the reduced maintenance over thelife of the pump.

Prime-assist pumps are by design trash pumps. Their uniquehigh-flow and high air handling characteristics are well suited folarge volume dewatering projects, well point dewatering, sewebypass applications, and other auto-start applications.

Diaphragm PumpsDiaphragm pumps use a positive displacement design rathethan centrifugal force to move water through the casing. Thismeans that the pump will deliver a specific amount of flow pestroke, revolution or cycle.

Engine-powered versions are the most common and typically usethe drive shaft to turn an offset connecting rod that is coupled

to a flexible diaphragm. The connecting rod alternately raises(expands) and lowers (contracts) the diaphragm at a rate of 60cycles per minute (RPM).

A vacuum is created inside the pump casing each time thediaphragm is raised (Figure 5A). This opens the inlet valve andseals the discharge valve allowing water and air to enter the

Diaphragm Pump Suction Stroke

Diaphragm Pump Discharge Stroke

Figure 5A

Figure 5B

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pump. When the diaphragm is lowered the resulting pressureseals the inlet and opens the outlet valve purging the pumphousing of water and air (Figure 5B). Unlike centrifugal designsthe water inside the casing is positively displacedand no re-circulation occurs.

Diaphragm pumps are commonly referred to as mud hogs, mudhens and mud suckers. Their names reflect their popularity foruse in applications where shallow depths and slurry water rendercentrifugal pumps ineffective.

A diaphragm pump provides the lowest rate of discharge andhead by comparison of any contractor pump. The most popularare 2 and 3-inch gasoline-powered models producing flows inthe range of 50 to 85 GPM. They have the ability to handle airwithout losing their prime and of handling water with a solidcontent greater than 25% by volume.

Slow-seepage applications are the most common uses fordiaphragm pumps. These conditions exist in any trench orexcavation where groundwater seeps slowly into the work siteand in areas with high water tables. In these environments

centrifugal pumps are unable to perform effectively because theirhigh-discharge volumes combined with low water levels wouldcause the pumps to quickly lose their prime.

Another design benefit is that diaphragm pumps do not run therisk of being damaged if run dry for long periods of time. Sincethere is no impeller or volute the only wear parts are the flapper(inlet and outlet) valves along with the diaphragm.

Submersible PumpsFew items provide as quick a return on investment and as long awork life as submersible pumps. Their compact and streamlined

design makes them ideal for wells and other jobs where spaceis limited. A typical rental company may stock pumps in sizesfrom 2 to 6-inches producing flows ranging from 45 to 790 GPMand heads up to 138 feet.

Submersibles have the advantage of being able to be work inthe water source being pumped. As a result the submersible isnot subject to the suction lift limitations of other typical contractorpumps. No suction hose is required helping to save money andtime while eliminating a potential source of problems. The pumpis limited only by the discharge head it is capable of producing.

Standard High Pressure Trash Diaphragm

COMMON 2-INCH PUMP DESIGNS

The pumps can also be classified by motor size and voltagerequirements. Smaller units, with !/3 and !/2 horsepower 115-volt motors are ideal for homeowner use or light-duty jobs.Experienced dewatering contractors will often choose pumps with230/460-volt 3-phase motors as they provide higher performanceand cost less to run over time.

The pump motors use a vertical shaft to turn the impeller andgenerate the velocity needed to create the discharge pressure.Water flows in through the bottom and is discharged out the topof the pump casing. Submersible trash pumps use a vortex designthat allows the pump to handle some solids without passingthrough the casing.

Typical electric submersible pumps

Combining electricity and water obviously brings a certainelement of risk. Further, it is difficult and often impossible to knowif there is a problem once the pump is submerged. As a result thepump should provide some built-in protections to ensure safetyand guard against damage to the equipment.

A high quality pump will have its motor housed in a watertightcompartment and equip it with thermal overload sensors thatshut down the motor to prevent damage from overheating. Pumpsshould also be used with GFCI protected circuits.

Some manufacturers may choose to list their pumps with anindependent testing laboratory. There are many laboratories


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Pumping FactorsThe altitude at which a pump is operated will enhance or diminishits performance. At higher elevations atmospheric pressure isdecreased reducing suction lift. For this reason the pump shouldbe located as close to the water source as possible. Table 1 shows

suction lift at several elevations.

TABLE 1 Suction Lift At Various Elevations

Altitude Suction Lift In Feet

Sea Level 10.0 15.0 20.0 25.02,000 Feet 8.8 13.2 17.6 22.04,000 Feet 7.8 11.7 15.6 19.56,000 Feet 6.9 10.4 13.8 17.38,000 Feet 6.2 9.3 12.4 15.510,000 Feet 5.7 8.6 11.4 14.3

Altitude affects engine performance as well. A rule of thumb isthat gasoline and diesel engines will lose 3% of their power forevery 1,000 feet of elevation. This is due to the thinner air or lackof oxygen at higher altitudes. The reduced engine speed resultsin reduced flow and head. Table 2 shows percentage drops in

performance as elevation increases.

Many engine manufacturers offer methods of overcoming this lossby offering high altitude cylinder heads, as well as carburetor jetsand air cleaners designed for use at higher elevations.

TABLE 2 Performance Loss At Various Elevations

Altitude Discharge Flow Discharge Head

Sea Level 100% 100%2,000 Feet 97% 95%4,000 Feet 95% 91%6,000 Feet 93% 87%

8,000 Feet 91% 83%10,000 Feet 88% 78%

Water temperature and suction lift have an inverse relationship.As water temperature increases the practical suction lift willdecrease, because warm water contains more entrained air,causing the pump to lose its ability to prime. If the water is toowarm, it may be necessary to locate the pump below the waterlevel. This creates a net posit ive suction head (NPSH). Always becautious when pumping hot water, as it can damage your pump.It is advisible to contact the pump manufacturer to determine themaximum operating temperature.

The Vacuum TestEach time the pump is returned from a rental, it is wise to runa simple vacuum test to determine the pumping and primingcapabilities of your equipment. This test takes only a fewseconds to run, and in no way requires a skilled technician.

To perform the vacuum test, the pump case should be filledwith water and a small amount of grease applied to the rubberface of the vacuum gauge. The discharge port should be openand free of obstruction. After the engine has been star ted andbrought up to the proper RPM, simply apply the vacuum gauge

assembly to the suction opening. In a few seconds, a vacuumwill start to develop and the gauge should remain in positionduring the test.

If the vacuum gaugereads 25", then restassured that the pump iscapable of lifting water 25feet (assuming that thesuction hose and fittingsare correctly applied). If this test is performed each time apump is sent out on a rent, you can eliminate the customerscomplaints of the pumps inability to prime.

If the pump has been checked and it pulls 25" of vacuum, thenthe problem will be elsewhere and you should refer to PumpTroubleshooting Guide.

VacuumGauge

SELECTING THE IDEAL PUMP FOR TYPICAL CONDITIONS

StandardApplication Centrifugal Diaphragm Trash Submersible

Clear Water X X

Slimy Water X X X XMuck Water X X X X

Mud Water X X X

Silt Water X X X

Abrasive Water X X X

High Solid Content Water X X

Slow Seepage Ditch Water X X

Septic Tank X X

Man Holes X X X


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Pump Troubleshooting GuideShould you receive calls from the field indicating that the pumpis not functioning properly, the following list may aid you in de-termining the problem.

If the pump does not deliver enough water:

Engine may not be running at the rated speed.

Strainer, inlet valve or the suction line may be clogged.

Suction line or fittings may leak air. Mechanical seal may be worn and leaking air or water. Check

weep hole.

There may be too much clearance between impeller andthe volute due to wear. For best performance refer tomanufacturers recommendations for proper adjustment.

Lining in the suction hose may be collapsing. This rubberlining inside the fabric layers may have pulled together underthe vacuum created by the pump.

Suction lift may be too high. At a 25-foot lift the pump deliversonly about 50% of the water it delivers at a 10-foot lift.

The suction hose may be too long, causing excessive frictionloss and reducing pump capacity.

Discharge head may be too high. Check hose or pipe frictionlosses. A larger hose or pipe may correct this condition.

If the pump does not develop enough pressure:

Engine may not be running at its rated speed.

Mechanical seal may be leaking. Check weep hole.

There may be too much clearance between the impeller andpump body or volute due to wear. For good performance, referto the manufacturers instructions for proper adjustment.

If the pump does not prime properly:

Make sure that the pump casing is filled with water.

Look in the suction line or fittings. Check to see that all fittingsare tight in the suction line and make sure there is no leak inthe hose itself.

Mechanical seal may be worn and leaking air.

Inlet valve rubber may be frozen to the seat.

Pump may be running too slowly.

The clearance between the impeller and pump body or volute

may be greatly worn. Refer to the manufacturers instructionmanual for proper adjustment.

Suction lift may be too high. At sea level the pump shouldnot be used on lifts in excess of 25 feet from the level of thewater to the center of the impeller. Keep the pump as closeto the water source as is safely possible.

Suction line or suction strainer may be clogged.

Water may be too warm for the suction lift being used (as thetemperature of the water increases above 60F, the practicasuction lift will decrease) making priming difficult. It may benecessary to replace the water in the pump case with freshcold water.

Making Your Pump Last

The following check list may aid you in keeping your pumps in topcondition. Check the following points on a monthly basis:

Priming speed

Capacity

Noise in pump casing

Gaskets and O-rings

Shaft seal leakage of air or water

Hose, hose washers and suction strainer

Check the following performance points on the engine:

Crankcase oil level

Spark plug condition

Air cleaner

Unusual engine noise

Proper RPM

Carburetor adjustment

Every six months, check the impeller for wear, and for clearancebetween the impeller face and the volute. Refer to the manufacturers recommendations. Check the shaft seal for wear, as welas the shaft sleeve. Clean the casing and volute passages.

Pump Storage Tips Drain the pump casing completely of water to prevent

damage from freezing.

If complete draining is not possible, pour a small amountof anti-freeze into the casing and rotate the pump shaftto ensure mixing.

Seal suction and discharge ports to prevent the entry of

debris or other foreign material. If the pump has an oil lubricated seal, drain the oil from

the seal cavaity and refill with 30-weight non-detergentmotor oil.

For water cooled-seals, place one-half pint of lubricating oil(new or used) through the discharge opening in the pumpand turn the engine over several times. This will preventexcessive corrosion and also will keep the mechanicalseal lubricated.


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Performance Curves chart water flow by comparing total head toflow rate.

Prime The creation of a vacuum inside the pump casing.

Pump Housing The pump body or casing. Depending on the designmay be made of plastic, aluminum, cast-iron or stainless steel.

Self-Priming The ability of a pump to purge air from its systemand creating an area of low pressure that permits water to flow into

the pump casing.Shock Mounts Rubber mounts used to dampen vibration from theengine and help prevent the pump from walking away.

Skid Mount Pump and engine mounting mounted on a base.

Slow Seepage Water that drains slowly into a trench or work areafrom the surrounding area. Possibly caused from run off or high watertables.

Solids Any particulate that passes through the pump: mud, sand,rock or other debris.

Staticacting by weight not motion, as opposed to dynamic.

Strainer A fitting at the end of the suction hose that prevents solids

from entering the pump larger than what it is capable of passing.Strain Relief Protector A support that prevents the electrical cord ofa submersible pump from being accidentally pulled out of the casing.

Suction Hose A reinforced hose used through which water flowsinto the suction end of a pump.

Suction Port Same as the inlet. The point where the suction hoseor pipe is connected to the pump.

System the network of hoses, pipes and valves linked to thepump.

Thermal Overload Sensors A feature built into the motor ofsubmersible pump that shuts it down should the operating temperaturebecome too high.

Viscosity The resistance to flow of a liquid at a given temperature.High viscosity liquids such as motor oil are more resistant to flow thanwater.

Volute A stationary housing inside the pump housing in which theimpeller rotates. It is used to separate air and water.

Water Hammer Energy transmitted from a sudden stoppage in theflow of water out of the pump.

Wear Plate A replaceable steel insert that fits inside the volute orsuction cover of a pump. Helps to form a vacuum with the impeller andreduce the cost of replacement parts.

Weep Hole A small opening on the underside of the pump where

it is joined to the engine. Allows quick detection of a leak before waterseeps into the oil sump of the engine.

GlossaryAir Bound A condition occurring when a centrifugal pump body isfilled with air and a vacuum can no longer be formed allowing waterto flow into the pump.

Capacity is the water handling capability of a pump commonlyexpressed as either gallons per minute (GPM) or gallons per hour(GPH).

Cavitationis the result of vapor bubbles imploding. This occurs whenthe amount of water flowing into the pump is restr icted or blocked.

Cleanout Covers On trash pumps a removable cover that allowseasy access to the interior of the pump casing for removal of anydebris.

Dewatering The removal of unwanted water-clear or dirty but freefrom hazardous material.

Diffuser A stationary housing similar to a volute in which the impellerrotates. Compact in design, it enables the pump to produce higherheads/pressures.

Discharge Hose A collapsible hose used to move the waterdischarged from the hose.

Discharge Port Same as the outlet. The point where the discharge

hose or pipe is connected to the pump.Drain Plugs Removable plugs used to drain water from the pumpduring periods of inactivity.

Dynamictakes into account motion, as opposed to static.

Flapper Valve Rubber molded around a steel weight that seals offthe inlet or outlet preventing water from either entering or exiting thepump.

Frame A wraparound tubular steel frame provides protection forthe casing and engine. These frames can simplify storage (stacking)and lifting.

Friction Lossrefers to reductions in flow due to turbulence as water

passes through hoses, pipes, fittings and elbows.Hazardous Material Any volatile, explosive or flammable liquid thatrequires special handling and should not be used with a dewateringpump.

Head A measurement of pressure typically expressed in feet/heador lb/in

Impeller A disk with multiple vanes. It is attached to the pump engineor motor and is used to create the centrifugal force necessary for movingwater through the pump casing.

Mechanical Seal A common wear part that forms a seal betweenthe pump and the engine or motor. Also prevents water from seepinginto the engine or motor.

Net Positive Suction Head (NPSH) positive flow of water to thesuction port of a pump.


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Notes


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MULTIQUIP INC.POST OFFICE BOX 6254CARSON, CA 90749310-537-3700 800-421-1244FAX: 310-537-3700E-MAIL: [email protected]

COPYRIGHT 2011, MULTIQUIP INC.PUMGID-929 Rev. D (04-11)

Documents

Pump Selection Handbook