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| {{other uses of|pump" or "pumps|Pump (disambiguation)}}
| | If you are a new business owner, then you've probably been contacted by organizations offering unbelievable marketing bargains to you. Like A novice in the business world, you'll be looking to increase your business and won't be certain that's what these advertising birds will rely on and where to turn. They will rely on the fact that you'll have marketing bucks sitting around that you feel you should spend to help increase your business.<br><br>Advertising strategies mightn't need imagination nonetheless it is absolutely needed for [http://www.advertisingservicesguide.com/ Ad Agency]. There's another common myth that government jobs are not acceptable in this industry. But the government careers provide security together with an excellent opportunity to learn your job.<br><br><br><br>Advertisement doesn't mean that you bombard people with ads even yet in their sleep! True, companies have enhanced advertisement spending but that is an overall effectation of the newer companies coming into the arena at the same time. publicity advertisement specialists were never this full with jobs! It's your liability if you are in this function to spell out your board of managers how an excessive amount of advertisement can backfire, when working for a company.<br><br>Plans like google adsense permit you to make by both ticks or page-perceptions. Ticks make reference to the clicks of the visitor of one's website for the ads you have inserted. The proportion of ticks per impression depends upon the click-through-rate or CTR. You are paid per-click towards the advertisements in your corner. The total amount varies depends on lots of factors. That means it's never continuous.<br><br>Bigger businesses understand the value of sub boards, too. Exactly how many times have you ever driven past folks supporting "moving away from business" or "Approval" signals around 119th and Metcalf? These high-traffic places are great locations to show off your communication. Add a sign spinner to produce a show of spinning putting and the sign and consumers may recognize.<br><br>You need to have quality information, to get traffic to your website. Those include articles, text, pictures, and other things that is media related. Be sure that they're unique and are your own work. Copying other's work is frowned upon by everyone who makes their very own stuff and is named plagiarism.<br><br>There's no way this might be complete without taking a look at two of the most used phrases in advertising, phrases which should setoff alarms each and every time you hear them yet always appear to hook somebody. This one always makes me wonder how stupid they think we're: "At this value, it will not last!" Really? Just how much more will it cost me for just one that will last? Oh, and just how can we forget "it's this that you have been waiting for"? Not me-what I've been awaiting is just a supermodel and a thousand dollars. |
| [[Image:Jet pump.jpg|thumb|right|A small, electrically powered pump]]
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| [[Image:Wasserwerk pumpe01.jpg|thumb|right|A large, electrically driven pump (electropump) for [[Water supply network|waterworks]] near the [[Hengsteysee]], [[Germany]].]]
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| A '''pump''' is a device that moves fluids ([[liquid]]s or [[gas]]es), or sometimes [[Slurry|slurries]], by mechanical action. Pumps can be classified into three major groups according to the method they use to move the fluid: ''direct lift'', ''displacement'', and ''gravity'' pumps.<ref>[http://www.fao.org/docrep/010/ah810e/AH810E05.htm#5.3.1 Pump classifications]. Fao.org. Retrieved on 2011-05-25.</ref>
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| Pumps operate by some mechanism (typically [[Reciprocating motion|reciprocating]] or [[Rotation|rotary]]), and consume [[energy]] to perform [[mechanical work]] by moving the fluid. Pumps operate via many energy sources, including manual operation, electricity, [[engines]], or [[wind power]], come in many sizes, from microscopic for use in medical applications to large industrial pumps.
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| Mechanical pumps serve in a wide range of applications such as [[Water well pump|pumping water from wells]], [[aquarium filter]]ing, [[Pond|pond filtering]] and [[aeration]], in the [[car industry]] for [[Water cooling|water-cooling]] and [[fuel injection]], in the [[energy industry]] for [[Pumping (oil well)|pumping oil]] and [[natural gas]] or for operating [[cooling tower]]s. In the [[medical industry]], pumps are used for biochemical processes in developing and manufacturing medicine, and as artificial replacements for body parts, in particular the [[artificial heart]] and [[penile prosthesis]].
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| In biology, many different types of chemical and bio-mechanical pumps have [[Evolutionary biology|evolved]], and [[biomimicry]] is sometimes used in developing new types of mechanical pumps.
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| ==Types==
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| Mechanical pumps may be '''submerged''' in the fluid they are pumping or be placed '''external '''to the fluid.
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| Pumps can be classified by their method of displacement into [[#Positive displacement pump|positive displacement pumps]], [[#Impulse Pumps|impulse pumps]], [[#Velocity pumps|velocity pumps]], [[#Gravity pumps|gravity pumps]], [[steam pumps]] and [[#Valveless pumps|valveless pumps]].
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| ===Positive displacement pump===
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| [[Image:Drehkolbenpumpe.jpg|thumb||right|A [[lobe pump]]]]
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| [[Image:Common Lobe Pump.png|thumb|right|upright|lobe pump internals]]
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| [[Image:Two moving spirals scroll pump.gif|thumb|Mechanism of a [[scroll pump]]]]
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| A positive displacement pump makes a fluid move by trapping a fixed amount and forcing (displacing) that trapped volume into the discharge pipe.
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| Some positive displacement pumps use an expanding cavity on the suction side and a decreasing cavity on the discharge side. Liquid flows into the pump as the cavity on the suction side expands and the liquid flows out of the discharge as the cavity collapses. The volume is constant through each cycle of operation.
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| ==== Positive displacement pump behavior and safety ====
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| Positive displacement pumps, unlike [[Centrifugal pump|centrifugal]] or [[roto-dynamic]] pumps, theoretically can produce the same flow at a given speed (RPM) no matter what the discharge pressure. Thus, positive displacement pumps are ''constant flow machines''. However, a slight increase in internal leakage as the pressure increases prevents a truly constant flow rate.
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| A positive displacement pump must not operate against a closed valve on the discharge side of the pump, because it has no shutoff head like centrifugal pumps. A positive displacement pump operating against a closed discharge valve continues to produce flow and the pressure in the discharge line increases until the line bursts, the pump is severely damaged, or both.
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| A relief or [[safety valve]] on the discharge side of the positive displacement pump is therefore necessary. The relief valve can be internal or external. The pump manufacturer normally has the option to supply internal relief or safety valves. The internal valve is usually only used as a safety precaution. An external relief valve in the discharge line, with a return line back to the suction line or supply tank provides increased safety.
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| ==== Positive displacement types ====
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| [[Image:Lysholm screw rotors.jpg|thumb|upright|Screw pump]]
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| A positive displacement pump can be further classified according to the mechanism used to move the fluid:1
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| * ''Rotary-type'' positive displacement: internal gear, screw, shuttle block, [[rotary vane pump|flexible vane or sliding vane]], circumferential piston, [[flexible impeller]], helical twisted roots (e.g. the Wendelkolben pump) or [[liquid ring]] [[vacuum pump]]s
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| * ''Reciprocating-type'' positive displacement: [[piston]] or [[diaphragm pump]]s
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| * ''Linear-type'' positive displacement: [[rope pump]]s and [[chain pump]]s
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| ===== Rotary positive displacement pumps =====
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| [[File:Rotary vane pump.svg|thumb|Rotary vane pump]]
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| Positive displacement rotary pumps move fluid using a rotating mechanism that creates a vacuum that captures and draws in the liquid{{Citation needed|date=May 2012}}.
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| ''Advantages:'' Rotary pumps are very efficient{{Citation needed|date=May 2012}} because they naturally remove air from the lines, eliminating the need to bleed the air from the lines manually. | |
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| ''Drawbacks:'' The nature of the pump demands very close clearances between the rotating pump and the outer edge, making it rotate at a slow, steady speed. If rotary pumps are operated at high speeds, the fluids cause erosion, which eventually causes enlarged clearances that liquid can pass through, which reduces efficiency.
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| Rotary positive displacement pumps fall into three main types:
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| * [[Gear pump]]s - a simple type of rotary pump where the liquid is pushed between two gears
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| * [[Screw pump]]s - the shape of the internals of this pump is usually two screws turning against each other to pump the liquid
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| * [[Rotary vane pump]]s - similar to [[scroll compressor]]s, these have a cylindrical rotor encased in a similarly shaped housing. As the rotor orbits, the vanes trap fluid between the rotor and the casing, drawing the fluid through the pump.
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| ===== Reciprocating positive displacement pumps =====
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| {{Main|Reciprocating pump}}
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| [[Image:Hand pump.png|thumb|Simple hand pump]]
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| [[Image:Pump-tah.jpg|thumb|upright|Hand-operated, reciprocating, positive displacement, water pump in [[Košice]]-[[Ťahanovce]], [[Slovakia]] (walking beam pump)]]
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| Reciprocating pumps move the fluid using one or more oscillating pistons, plungers, or membranes (diaphragms), while valves restrict fluid motion to the desired direction.
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| Pumps in this category range from ''simplex'', with one cylinder, to in some cases ''quad'' (four) cylinders, or more. Many reciprocating-type pumps are ''duplex'' (two) or ''triplex'' (three) cylinder. They can be either ''single-acting'' with suction during one direction of piston motion and discharge on the other, or ''double-acting'' with suction and discharge in both directions. The pumps can be powered manually, by air or steam, or by a belt driven by an engine. This type of pump was used extensively in the 19th century—in the early days of steam propulsion—as boiler feed water pumps. Now reciprocating pumps typically pump highly viscous fluids like concrete and heavy oils, and serve in special applications that demand low flow rates against high resistance. Reciprocating hand pumps were widely used to pump water from wells. Common [[bicycle pump]]s and foot pumps for [[Inflatable|inflation]] use reciprocating action.
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| These positive displacement pumps have an expanding cavity on the suction side and a decreasing cavity on the discharge side. Liquid flows into the pumps as the cavity on the suction side expands and the liquid flows out of the discharge as the cavity collapses. The volume is constant given each cycle of operation.
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| Typical reciprocating pumps are:
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| * ''[[Plunger pump]]s'' - a reciprocating plunger pushes the fluid through one or two open valves, closed by suction on the way back.
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| * ''[[Diaphragm pump]]s'' - similar to plunger pumps, where the plunger pressurizes hydraulic oil which is used to flex a diaphragm in the pumping cylinder. Diaphragm valves are used to pump hazardous and toxic fluids.
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| * ''[[Piston pump]]s'' displacement pumps'' - usually simple devices for pumping small amounts of liquid or gel manually. The common hand soap dispenser is such a pump.
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| * ''[[Radial piston pump]]s''
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| ===== Various positive displacement pumps =====
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| The positive displacement principle applies in these pumps:
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| * [[Lobe pump|Rotary lobe pump]]
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| * [[Progressive cavity pump]]
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| * [[Gear pump|Rotary gear pump]]
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| * [[Piston pump]]
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| * [[Diaphragm pump]]
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| * [[Screw pump]]
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| * [[Gear pump]]
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| * [[Hydraulic pump]]
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| * [[Rotary vane pump]]
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| * [[Regenerative pump|Regenerative (peripheral) pump]]
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| * [[Peristaltic pump]]
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| * [[Rope pump]]
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| * [[Flexible impeller]]
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| * Rotolliptic pump
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| ======Gear pump======
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| {{Main|Gear pump}}
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| [[Image:Gear pump.png|thumb|Gear pump]]
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| This is the simplest of rotary positive displacement pumps. It consists of two meshed gears that rotate in a closely fitted casing. The tooth spaces trap fluid and force it around the outer periphery. The fluid does not travel back on the meshed part, because the teeth mesh closely in the centre. Gear pumps see wide use in car engine oil pumps and in various [[hydraulic power pack]]s.
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| ======Screw pump======
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| {{Main|Screw pump}}
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| A [[Screw pump]] is a more complicated type of rotary pump that uses two or three screws with opposing thread—e.g., one screw turns clockwise and the other counterclockwise. The screws are mounted on parallel shafts that have gears that mesh so the shafts turn together and everything stays in place. The screws turn on the shafts and drive fluid through the pump. As with other forms of rotary pumps, the clearance between moving parts and the pump's casing is minimal.
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| ======Progressing cavity pump======
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| {{Main|Progressive cavity pump}}
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| [[Image:Pcp-thumb.gif|right|link=Image:Progressive_cavity_pump_animation.gif|Cavity pump]]
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| Widely used for pumping difficult materials, such as sewage sludge contaminated with large particles, this pump consists of a helical rotor, about ten times as long as its width. This can be visualized as a central core of diameter ''x'' with, typically, a curved spiral wound around of thickness half ''x'', though in reality it is manufactured in single casting. This shaft fits inside a heavy duty rubber sleeve, of wall thickness also typically ''x''. As the shaft rotates, the rotor gradually forces fluid up the rubber sleeve. Such pumps can develop very high pressure at low volumes.
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| ======Roots-type pumps======
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| {{main|Roots-type supercharger}}
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| [[image:lobbenpomp.gif|right|thumb]]
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| Named after the Roots brothers who invented it, this [[lobe pump]] displaces the liquid trapped between two long helical rotors, each fitted into the other when perpendicular at 90°, rotating inside a triangular shaped sealing line configuration, both at the point of suction and at the point of discharge. This design produces a continuous flow with equal volume and no vortex. It can work at low [[pulsation]] rates, and offers gentle performance that some applications require.
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| Applications include:
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| * High capacity [[gas compressor|industrial air compressors]]
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| * [[Roots supercharger]]s on [[internal combustion engine]]s.
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| * A brand of civil defense siren, the [[Federal Signal Corporation]]'s [[Thunderbolt siren|Thunderbolt]].
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| ======Peristaltic pump======
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| {{Main|Peristaltic pump}}
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| [[Image:eccentric pump.gif|thumb|360 Degree Peristaltic Pump]]
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| A ''peristaltic pump'' is a type of positive displacement pump. It contains fluid within a flexible tube fitted inside a circular pump casing (though linear peristaltic pumps have been made). A number of ''rollers'', ''shoes'', or ''wipers'' attached to a [[rotor (turbine)|rotor]] compresses the flexible tube. As the rotor turns, the part of the tube under compression closes (or ''occludes''), forcing the fluid through the tube. Additionally, when the tube opens to its natural state after the passing of the cam it draws (''restitution'') fluid flow into the pump. This process is called [[peristalsis]] and is used in many biological systems such as the [[gastrointestinal tract]].
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| ======Plunger pumps======
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| {{Main|Plunger pump}}
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| [[File:Piston VS Plunger Pump.png|thumb|right|A plunger pump compared to a [[piston pump]] ]]
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| ''Plunger pumps'' are reciprocating positive displacement pumps.
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| These consist of a cylinder with a reciprocating plunger. The suction and discharge valves are mounted in the head of the cylinder. In the suction stroke the plunger retracts and the suction valves open causing suction of fluid into the cylinder. In the forward stroke the plunger pushes the liquid out of the discharge valve.
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| Efficiency and common problems: With only one cylinder in plunger pumps, the fluid flow varies between maximum flow when the plunger moves through the middle positions, and zero flow when the plunger is at the end positions. A lot of energy is wasted when the fluid is accelerated in the piping system. Vibration and ''[[water hammer]]'' may be a serious problem. In general the problems are compensated for by using two or more cylinders not working in phase with each other.
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| ======Triplex-style plunger pumps======
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| Triplex plunger pumps use three plungers, which reduces the pulsation of single reciprocating plunger pumps. Adding a pulsation dampener on the pump outlet can further smooth the ''pump ripple'', or ripple graph of a pump transducer. The dynamic relationship of the high-pressure fluid and plunger generally requires high-quality plunger seals. Plunger pumps with a larger number of plungers have the benefit of increased flow, or smoother flow without a pulsation dampener. The increase in moving parts and crankshaft load is one drawback.
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| Car washes often use these triplex-style plunger pumps (perhaps without pulsation dampeners). In 1968, William Bruggeman significantly reduced the size of the triplex pump and increased the lifespan so that car washes could use equipment with smaller footprints. Durable high pressure seals, low pressure seals and oil seals, hardened crankshafts, hardened connecting rods, thick ceramic plungers and heavier duty ball and roller bearings improve reliability in triplex pumps. Triplex pumps now are in a myriad of markets across the world.
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| Triplex pumps with shorter lifetimes are commonplace to the home user. A person who uses a home pressure washer for 10 hours a year may be satisfied with a pump that lasts 100 hours between rebuilds. Industrial-grade or continuous duty triplex pumps on the other end of the quality spectrum may run for as much as 2,080 hours a year.
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| The oil and gas drilling industry uses massive semi trailer-transported triplex pumps called [[mud pump]]s to pump [[drilling mud]], which cools the drill bit and carries the cuttings back to the surface.<ref>
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| [http://www.pumpingperfected.com/pumps/ "Drilling Pumps"].
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| [[Gardner Denver]].
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| </ref> | |
| Drillers use triplex or even quintuplex pumps to inject water and solvents deep into shale in the extraction process called ''[[fracking]]''.<ref>
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| [http://www.pumpingperfected.com/pumps/stimulation-fracturing/gd-2500/ "Stimulation and Fracturing pumps: Reciprocating, Quintuplex Stimulation and Fracturing Pump"]. | |
| Gardner Denver.
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| </ref>
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| ======Compressed-air-powered double-diaphragm pumps======
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| One modern application of positive displacement diaphragm pumps is compressed-air-powered double-[[Diaphragm (mechanical device)|diaphragm]] pumps. Run on compressed air these pumps are intrinsically safe by design, although all manufacturers offer ATEX certified models to comply with industry regulation. These pumps are relatively inexpensive and can perform a wide variety of duties, from pumping water out of [[bunding|bunds]], to pumping hydrochloric acid from secure storage (dependent on how the pump is manufactured – elastomers / body construction). Lift is normally limited to roughly 6m although heads can reach almost 200 Psi.{{Citation needed|date=November 2009}}.
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| ======Rope pumps======
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| {{Main|Rope pump}}
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| [[File:Rope Pump.svg|thumb|Rope pump schematic]]
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| Devised in China as chain pumps over 1000 years ago, these pumps can be made from very simple materials: A rope, a wheel and a PVC pipe are sufficient to make a simple rope pump. For this reason they have become extremely popular around the world since the 1980s. Rope pump efficiency has been studied by grass roots organizations and the techniques for making and running them have been continuously improved.<ref>[http://tanzaniawater.blogspot.com/2010/08/hi-its-cai.html Tanzania water] blog - example of grass roots researcher telling about his study and work with the rope pump in Africa.</ref>
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| ======Flexible impeller pump======
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| {{Main|Flexible impeller}}
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| [[Image:Flexible_impeller_pump.gif|thumb|Flexible impeller pump<br>
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| The variation of vane volume during the rotation cause the dry selfpriming feature of the pump.<br>
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| Pump is also reversible.]]
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| [[File:pulser pump.jpg|thumb|The pulser pump]]
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| ======Rotolliptic pumps======
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| The [[Rotolliptic Mechanism]] is a rotary positive displacement pump that draws in and discharges fluid continually, without the need for valves. The mechanism operates based on a principle that an ellipse of a specific geometry, rotating about its centre at half the rate as its circular orbit maintains a constant contact vertex on the housing. This contact vertex acts as a seal to separate the intake and outlet regions and facilitates a movement of fluid trapped between the rotor and the housing. {{Citation needed|date=December 2013}}.
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| ===Impulse Pumps===
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| Impulse pumps use pressure created by gas (usually air). In some impulse pumps the gas trapped in the liquid (usually water), is released and accumulated somewhere in the pump, creating a pressure that can push part of the liquid upwards.
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| Impulse pumps include:
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| * ''[[Hydraulic ram]] pumps'' – kinetic energy of a low-head water supply is stored temporarily in an air-bubble [[hydraulic accumulator]], then used to drive water to a higher head.
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| * ''[[Pulser pump]]s'' - run with natural resources, by kinetic energy only.
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| * ''[[Airlift pump]]s'' - run on air inserted into pipe, pushing up the water, when bubbles move upward, or on pressure inside pipe pushing water up.
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| ====Hydraulic ram pumps====
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| [[Image:Airlift Pump vs Geyser Pump.JPG|thumb|Airlift pump vs. Geyser pump]]
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| A [[hydraulic ram]] is a water pump powered by hydropower.
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| It takes in water at relatively low pressure and high flow-rate and outputs water at a higher hydraulic-head and lower flow-rate. The device uses the [[water hammer]] effect to develop pressure that lifts a portion of the input water that powers the pump to a point higher than where the water started.
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| The hydraulic ram is sometimes used in remote areas, where there is both a source of low-head hydropower, and a need for pumping water to a destination higher in elevation than the source. In this situation, the ram is often useful, since it requires no outside source of power other than the kinetic energy of flowing water.
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| ===Velocity pumps===
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| [[Image:Centrifugal 2.png|thumb|right|A centrifugal pump uses a spinning "impeller" with backward-swept arms]]
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| [[Rotodynamic pump]]s (or dynamic pumps) are a type of velocity pump in which [[kinetic energy]] is added to the fluid by increasing the flow velocity. This increase in energy is converted to a gain in potential energy (pressure) when the velocity is reduced prior to or as the flow exits the pump into the discharge pipe. This conversion of kinetic energy to pressure is explained by the ''[[First law of thermodynamics]]'', or more specifically by ''[[Bernoulli's principle]]''.
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| Dynamic pumps can be further subdivided according to the means in which the velocity gain is achieved.<ref>[http://www.pumps.org/content_detail_pumps.aspx?id=1768 Welcome to the Hydraulic Institute]. Pumps.org. Retrieved on 2011-05-25.</ref>
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| These types of pumps have a number of characteristics:
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| # Continuous energy
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| # Conversion of added energy to increase in [[kinetic energy]] (increase in velocity)
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| # Conversion of increased velocity (kinetic energy) to an increase in pressure head
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| A practical difference between dynamic and positive displacement pumps is how they operate under closed valve conditions. Positive displacement pumps physically displace fluid, so closing a valve downstream of a positive displacement pump produces a continual pressure build up that can cause mechanical failure of pipeline or pump. Dynamic pumps differ in that they can be safely operated under closed valve conditions (for short periods of time).
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| ====Centrifugal pump====
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| {{Main|Centrifugal pump}}
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| [[Image:Centrifugal Pump.png|thumb|Centrifugal pump]]
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| [[File:Open Type Centrifugal Pump Impeller.ogv|thumb|Open Type Centrifugal Pump Impeller]]
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| A ''centrifugal pump'' is a rotodynamic pump that uses a rotating [[impeller]] to increase the pressure and flow rate of a fluid. Centrifugal pumps are the most common type of pump used to move liquids through a piping system. The fluid enters the pump impeller along or near to the rotating axis and is accelerated by the impeller, flowing radially outward or axially into a diffuser or [[volute]] chamber, from where it exits into the downstream piping system. Centrifugal pumps are typically used for large discharge through smaller heads.
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| Centrifugal pumps are most often associated with the radial-flow type. However, the term "centrifugal pump" can be used to describe all impeller type rotodynamic pumps<ref name=PumpHandbook >{{cite book
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| | last1 = Karassik | first1 = Igor J.
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| | last2 = Messina | first2 = Joseph P.
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| | last3 = Cooper | first3 = Paul
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| | last4 = Heald | first4 = Charles C.
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| | title = Pump Handbook
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| | edition = 3rd
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| | publisher = McGraw-Hill
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| | location = New York
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| | year = 2001
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| | isbn = 978-1-59124-361-8}}
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| </ref> including the radial, axial and mixed-flow variations. | |
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| ====Radial-flow pumps====
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| Often simply referred to as centrifugal pumps. The fluid enters along the axial plane, is accelerated by the impeller and exits at right angles to the shaft(radially). Radial-flow pumps operate at higher pressures and lower flow rates than axial and mixed-flow pumps.
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| ====Axial-flow pumps====
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| {{Main|Axial-flow pump}}
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| [[Image:Axial 2.png|thumb|Axial pump (propeller in pipe)]]
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| Axial-flow pumps differ from radial-flow in that the fluid enters and exits along the same direction parallel to the rotating shaft. The fluid is not accelerated but instead "lifted" by the action of the impeller. They may be likened to a propeller spinning in a length of tube. Axial-flow pumps operate at much lower pressures and higher flow rates than radial-flow pumps.
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| ====Mixed-flow pumps====
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| Mixed-flow pumps function as a compromise between radial and axial-flow pumps. The fluid experiences both radial acceleration and lift and exits the impeller somewhere between 0 and 90 degrees from the axial direction. As a consequence mixed-flow pumps operate at higher pressures than axial-flow pumps while delivering higher discharges than radial-flow pumps. The exit angle of the flow dictates the pressure head-discharge characteristic in relation to radial and mixed-flow.
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| ====Eductor-jet pump====
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| {{Main|Eductor-jet pump}}
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| This uses a jet, often of steam, to create a low pressure. This low pressure sucks in fluid and propels it into a higher pressure region.
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| ===Gravity pumps===
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| Gravity pumps include the ''[[syphon]]'' and ''[[Heron's fountain]]''. The ''[[hydraulic ram]]'' is also sometimes called a gravity pump.
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| ===Steam pumps===
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| Steam pumps have been for a long time mainly of historical interest. They include any type of pump powered by a [[steam engine]] and also [[pistonless pump]]s such as [[Thomas Savery]]'s or the [[Pulsometer steam pump]].
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| Recently there has been a resurgence of interest in low power solar steam pumps for use in smallholder irrigation in developing countries. Previously small steam engines have not been viable because of escalating inefficiencies as vapour engines decrease in size. However the use of modern engineering materials coupled with alternative engine configurations has meant that these types of system are now a cost effective opportunity.
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| ===Valveless pumps===
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| [[Valveless pumping]] assists in fluid transport in various biomedical and engineering systems. In a valveless pumping system, no valves (or physical occlusions) are present to regulate the flow direction. The fluid pumping efficiency of a valveless system, however, is not necessarily lower than that having valves. In fact, many fluid-dynamical systems in nature and engineering more or less rely upon valveless pumping to transport the working fluids therein. For instance, blood circulation in the cardiovascular system is maintained to some extent even when the heart’s valves fail. Meanwhile, the embryonic vertebrate heart begins pumping blood long before the development of discernible chambers and valves. In [[microfluidics]], valveless [[impedance pump]]s have been fabricated, and are expected to be particularly suitable for handling sensitive biofluids. Ink jet printers operating on the [[Piezoelectricity#Actuators|Piezoelectric transducer]] principal also use valveless pumping. The pump chamber is emptied through the printing jet due to reduced flow impedance in that direction and refilled by capillary action.
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| ==Pump repairs==
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| Examining pump repair records and MTBF (mean time between failures) is of great importance to responsible and conscientious pump users. In view of that fact, the preface to the 2006 Pump User’s Handbook alludes to "pump failure" statistics. For the sake of convenience, these failure statistics often are translated into MTBF (in this case, installed life before failure).<ref name="mt-online.com">[http://www.mt-online.com/mt-rokstories-places-holder/73-october/839-pump-statistics-should-shape-strategies.html Pump Statistics Should Shape Strategies]. Mt-online.com (2008-10-01). Retrieved on 2011-05-25.</ref>
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| In early 2005, Gordon Buck, [[John Crane Inc.]]’s chief engineer for Field Operations in Baton Rouge, LA, examined the repair records for a number of refinery and chemical plants to obtain meaningful reliability data for centrifugal pumps. A total of 15 operating plants having nearly 15,000 pumps were included in the survey. The smallest of these plants had about 100 pumps; several plants had over 2000. All facilities were located in the United States. In addition, considered as "new," others as "renewed" and still others as "established." Many of these plants—but not all—had an alliance arrangement with John Crane. In some cases, the alliance contract included having a [[John Crane Inc.]] technician or engineer on-site to coordinate various aspects of the program.
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| Not all plants are refineries, however, and different results occur elsewhere. In chemical plants, pumps have traditionally been "throw-away" items as chemical attack limits life. Things have improved in recent years, but the somewhat restricted space available in "old" DIN and ASME-standardized stuffing boxes places limits on the type of seal that fits. Unless the pump user upgrades the seal chamber, the pump only accommodates more compact and simple versions. Without this upgrading, lifetimes in chemical installations are generally around 50 to 60 percent of the refinery values.
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| Unscheduled maintenance is often one of the most significant costs of ownership, and failures of mechanical seals and bearings are among the major causes. Keep in mind the potential value of selecting pumps that cost more initially, but last much longer between repairs. The MTBF of a better pump may be one to four years longer than that of its non-upgraded counterpart. Consider that published average values of avoided pump failures range from $2600 to $12,000. This does not include lost opportunity costs. One pump fire occurs per 1000 failures. Having fewer pump failures means having fewer destructive pump fires.
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| As has been noted, a typical pump failure based on actual year 2002 reports, costs $5,000 on average. This includes costs for material, parts, labor and overhead. Extending a pump's MTBF from 12 to 18 months would save $1,667 per yr—which might be greater than the cost to upgrade the centrifugal pump's reliability.<ref name="mt-online.com" /><ref>[http://www.engineeringnews.co.za/article/submersible-slurry-pumps-in-high-demand-2006-10-06 Submersible slurry pumps in high demand]. Engineeringnews.co.za. Retrieved on 2011-05-25.</ref><ref>{{cite news| last = Wasser, Goodenberger | first = Jim and Bob | title = Extended Life, Zero Emissions Seal for Process Pumps | work= John Crane Technical Report | publisher = Routledge | id = TRP 28017 | date=November 1993}}</ref>
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| ==Applications==
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| [[Image:Dosierpumpe.gif|thumb|Metering pump for [[gasoline]] and [[Gasoline additive|additive]]s.]]
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| Pumps are used throughout society for a variety of purposes. Early applications includes the use of the [[windmill]] or [[watermill]] to pump water. Today, the pump is used for irrigation, [[plumbing|water supply]], gasoline supply, [[air conditioning]] systems, [[refrigeration]] (usually called a compressor), chemical movement, [[sewage]] movement, flood control, marine services, etc.
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| Because of the wide variety of applications, pumps have a plethora of shapes and sizes: from very large to very small, from handling gas to handling liquid, from high pressure to low pressure, and from high volume to low volume.
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| ===Priming a pump===
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| Typically, a liquid pump can't simply draw air until the feed line and pump fill with the liquid that requires pumping. An operator must introduce liquid into the system to initiate the pumping. This is called ''priming'' the pump. Loss of prime is usually due to ingestion of air into the pump. The clearances and displacement ratios in pumps for liquids and other more viscous fluids usually cannot displace air due to its lower density.
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| ===Pumps as public water supplies===
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| [[File:Taccola first piston.jpg|thumb|First European depiction of a [[piston]] pump, by [[Taccola]], c.1450.<ref>{{cite book| last = Hill | first = Donald Routledge | title = A History of Engineering in Classical and Medieval Times | location = London | publisher = Routledge | year = 1996 | page = 143 | isbn = 0-415-15291-7 | url = http://books.google.com/books?id=MqSXc5sGZJUC&pg=PA143&dq=Taccola+first+piston}}</ref>]]
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| One sort of pump once common worldwide was a hand-powered water pump, or 'pitcher pump'. It was commonly installed over community [[water well]]s in the days before piped water supplies.
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| In parts of the British Isles, it was often called ''the parish pump''. Though such community pumps are no longer common, people still used the expression ''parish pump'' to describe a place or forum where matters of local interest are discussed.<ref>{{cite web|url=http://dictionary.reference.com/browse/parish+pump|title=Online Dictionary – Parish Pump|accessdate=2010-11-22}}</ref>
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| Because water from pitcher pumps is drawn directly from the soil, it is more prone to contamination. If such water is not filtered and purified, consumption of it might lead to gastrointestinal or other water-borne diseases. A notorious case is the [[1854 Broad Street cholera outbreak]]. At the time it was not known how cholera was transmitted, but physician [[John Snow (physician)|John Snow]] suspected contaminated water and had the handle of the public pump he suspected removed; the outbreak then subsided.
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| Modern hand-operated community pumps are considered the most sustainable low-cost option for safe water supply in resource-poor settings, often in rural areas in developing countries. A hand pump opens access to deeper groundwater that is often not polluted and also improves the safety of a well by protecting the water source from contaminated buckets. Pumps such as the Afridev pump are designed to be cheap to build and install, and easy to maintain with simple parts. However, scarcity of spare parts for these type of pumps in some regions of Africa has diminished their utility for these areas.{{Citation needed|date=January 2009}}
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| ===Sealing multiphase pumping applications===
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| Multiphase pumping applications, also referred to as tri-phase, have grown due to increased oil drilling activity. In addition, the economics of multiphase production is attractive to upstream operations as it leads to simpler, smaller in-field installations, reduced equipment costs and improved production rates. In essence, the multiphase pump can accommodate all fluid stream properties with one piece of equipment, which has a smaller footprint. Often, two smaller multiphase pumps are installed in series rather than having just one massive pump.
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| For midstream and upstream operations, multiphase pumps can be located onshore or offshore and can be connected to single or multiple wellheads. Basically, multiphase pumps are used to transport the untreated flow stream produced from oil wells to downstream processes or gathering facilities. This means that the pump may handle a flow stream (well stream) from 100 percent gas to 100 percent liquid and every imaginable combination in between. The flow stream can also contain abrasives such as sand and dirt. Multiphase pumps are designed to operate under changing/fluctuating process conditions. Multiphase pumping also helps eliminate emissions of greenhouse gases as operators strive to minimize the flaring of gas and the venting of tanks where possible.<ref name="pump-zone.com">[http://pump-zone.com/seals/seals/sealing-multiphase-pumping-applications.html Sealing Multiphase Pumping Applications | Seals]. Pump-zone.com. Retrieved on 2011-05-25.</ref>
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| ==== Types and features of multiphase pumps ====
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| ''Helico-Axial Pumps (Centrifugal)''
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| A rotodynamic pump with one single shaft that requires two mechanical seals, this pump uses an open-type axial impeller. It's often called a ''Poseidon pump'', and can be described as a cross between an axial compressor and a centrifugal pump.
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| ''Twin Screw (Positive Displacement)''
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| The twin screw pump is constructed of two inter-meshing screws that move the pumped fluid. Twin screw pumps are often used when pumping conditions contain high gas volume fractions and fluctuating inlet conditions. Four mechanical seals are required to seal the two shafts.
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| ''Progressive Cavity Pumps (Positive Displacement)'' | |
| Progressive cavity pumps are single-screw types typically used in shallow wells or at the surface. This pump is mainly used on surface applications where the pumped fluid may contain a considerable amount of solids such as sand and dirt.
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| ''Electric Submersible Pumps (Centrifugal)''
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| These pumps are basically multistage centrifugal pumps and are widely used in oil well applications as a method for artificial lift. These pumps are usually specified when the pumped fluid is mainly liquid.
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| ''Buffer Tank''
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| A buffer tank is often installed upstream of the pump suction nozzle in case of a slug flow. The buffer tank breaks the energy of the liquid slug, smoothes any fluctuations in the incoming flow and acts as a sand trap.
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| As the name indicates, multiphase pumps and their mechanical seals can encounter a large variation in service conditions such as changing process fluid composition, temperature variations, high and low operating pressures and exposure to abrasive/erosive media. The challenge is selecting the appropriate mechanical seal arrangement and support system to ensure maximized seal life and its overall effectiveness.<ref name="pump-zone.com"/><ref>[http://www.sealsentinel.com/interphex/Day1-Story2.html John Crane Seal Sentinel – John Crane Increases Production Capabilities with Machine that Streamlines Four Machining Functions into One]. Sealsentinel.com. Retrieved on 2011-05-25.</ref><ref>[http://www.engineeringnews.co.za/article/vacuum-pump-new-on-sa-market-2005-04-22 Vacuum pump new on SA market]. Engineeringnews.co.za. Retrieved on 2011-05-25.</ref>
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| ==Specifications==
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| Pumps are commonly rated by [[horsepower]], [[flow rate]], outlet [[pressure]] in metres (or feet) of head, inlet [[suction]] in suction feet (or metres) of head.
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| The head can be simplified as the number of feet or metres the pump can raise or lower a column of water at [[atmospheric pressure]].
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| From an initial design point of view, engineers often use a quantity termed the [[specific speed]] to identify the most suitable pump type for a particular combination of flow rate and head.
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| ==Pump material==
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| The pump material can be Stainless steel (SS 316 or SS 304), cast iron etc. It depends on the application of the pump. In the water industry and for pharma applications SS 316 is normally used, as stainless steel gives better results at high temperatures.
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| ==Laraib Pumping power==
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| {{main|Bernoulli's equation}}
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| The power imparted into a fluid increases the energy of the fluid per unit volume. Thus the power relationship is between the conversion of the mechanical energy of the pump mechanism and the fluid eliminate within the pump. In general, this is governed by a series of simultaneous differential equations, known as the [[Navier-Stokes equations]]. However a more simple equation relating only the different energies in the fluid, known as [[Bernoulli's equation]] can be used. Hence the power, P, required by the pump:
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| : <math>P = \frac{\Delta P Q}{\eta}</math>
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| where ΔP is the change in [[total pressure]] between the inlet and outlet (in Pa), and Q, the fluid flowrate is given in m³/s. The total pressure may have gravitational, [[static pressure]] and [[kinetic energy]] components; i.e. energy is distributed between change in the fluid's gravitational potential energy (going up or down hill), change in velocity, or change in static pressure. η is the pump efficiency, and may be given by the manufacturer's information, such as in the form of a [[pump curve]], and is typically derived from either fluid dynamics simulation (i.e. solutions to the [[Navier-stokes]] for the particular pump geometry), or by testing. The efficiency of the pump depends upon the pump's configuration and operating conditions (such as rotational speed, fluid density and viscosity etc.)
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| : <math> \Delta P = {(v_2^2 - v_1^2) \over 2}+\Delta z g+{\Delta p_{\mathrm{static}}\over\rho}</math> | |
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| For a typical "pumping" configuration, the work is imparted on the fluid, and is thus positive. For the fluid imparting the work on the pump (i.e. a [[turbine]]), the work is negative power required to drive the pump is determined by dividing the output power by the pump efficiency. Furthermore, this definition encompasses pumps with no moving parts, such as a [[siphon]].
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| ==Pump efficiency==
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| Pump efficiency is defined as the ratio of the power imparted on the fluid by the pump in relation to the power supplied to drive the pump. Its value is not fixed for a given pump, efficiency is a function of the discharge and therefore also operating head. For centrifugal pumps, the efficiency tends to increase with flow rate up to a point midway through the operating range (peak efficiency) and then declines as flow rates rise further. Pump performance data such as this is usually supplied by the manufacturer before pump selection. Pump efficiencies tend to decline over time due to wear(e.g. increasing clearances as impellers reduce in size).
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| When a system design includes a centrifugal pump, an important issue it its design is matching the ''head loss-flow characteristic'' with the pump so that it operates at or close to the point of its maximum efficiency.
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| Pump efficiency is an important aspect and pumps should be regularly tested. [[Thermodynamic pump testing]] is one method.
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| == See also ==
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| {{columns-list|3|
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| * [[Affinity laws]]
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| * [[Balancing machine]]
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| * [[Beam pump]] and [[walking beam pump]]
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| * [[Bellows]] - a simple air pumping device
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| * [[Bicycle pump]]
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| * [[Breast pump]]
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| * [[Bush Pump]]
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| * [[Chopper pump]]
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| * [[Concrete pump]]
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| * [[Comparison of pumps]]
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| * [[Cyclic pump]]
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| * [[Fire pump]]
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| * [[Gas compressor]]s
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| * [[Gerotor]]
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| * [[Hand pump]]
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| * [[Honda pumps]]
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| * [[Hydraulic ram pump]]
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| * [[Inductive Pump]]
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| * [[Intelligent pump]]
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| * [[Jockey pump]]
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| * [[Metering pump]]
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| * [[Peristaltic pump]]
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| * [[Pulser Pump]]
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| * [[Pumping station]]
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| * [[Pumpjack]] (oil pump)
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| * [[Scoop wheel]]
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| * Scroll pump, most used in [[scroll compressor]]s
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| * [[Sine pump]]
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| * [[Rotodynamic pump]]
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| * [[Tesla turbine]]
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| * [[Thermodynamic pump testing]]
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| * [[Vacuum pump]]
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| * [[Wind pump]]
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| * [[Slip factor]]
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| * [[Biological pump]] - a phenomenon in nature studied in [[ecology]] and [[meteorology]]
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| * [[Ion transporter|Ion pump]] - bio-chemical pump used in living cell [[membranes]] to transfer ions
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| * [[Pump organ]] - musical instrument using [[bellows]]
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| }}
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| == References ==
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| {{reflist|30em}}
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| ==Further reading==
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| * Australian Pump Manufacturers' Association. ''Australian Pump Technical Handbook'', 3rd edition. Canberra: Australian Pump Manufacturers' Association, 1987. ISBN 0-7316-7043-4.
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| * Hicks, Tyler G. and Theodore W. Edwards. ''Pump Application Engineering''. McGraw-Hill Book Company.1971. ISBN 07-028741-4
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| * {{cite book|editor=Karassik, Igor|title=Pump Handbook|publisher=McGraw Hill|year=2007|url=http://books.google.com/books?id=MNq-mAEACAAJ|ISBN=9780071460446|edition=4}}
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| * Robbins, L. B. [http://books.google.com/books?id=7igDAAAAMBAJ&pg=PA83 "Homemade Water Pressure Systems"]. ''[[Popular Science]]'', February 1919, pages 83–84. Article about how a homeowner can easily build a pressurized home water system that does not use electricity.
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| == External links ==
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| {{Commons category|Pumps}}
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| * [http://www.pumpschool.com www.pumpschool.com]—Pump education devoted primarily to rotary positive displacement pumps
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| * [http://www.nciweb.net/eductor1.htm]— See Jet Pumps
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| {{Machines}}
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| [[Category:Fluid dynamics]]
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| [[Category:Pumps| ]]
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