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8/2/2019 Hossam Pumps
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Contents
1- Introduction
2-Pumps classification & types
3-Types of pumps (using & figures)4-Application in general 5-Application in marine field
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1. Introduction
Pumps and fans move fluids or gas from one location to another. The fluid or gas is moved
using a rotating set of blades that draw the fluid in, then push it out.
The construction of a pump or fan has some basic similarities. A rotating impeller is
enclosed inside a specially shaped shell. Imagine the airflow being drawn into a hair dryer.
Air is taken into the centre of the dryer and it is then pushed along the vanes of the impeller
(fan blades) out through a nozzle.
The fluid will be forced to flow at a particular rate, i.e. the fluid will be pushed along by the
pump .
A pump is a device used to move fluids, such as liquids, gases or slurries.
1.2 Pumping system characteristics
:1.2.1 Resistance of the system
head Pressure is needed to pump the liquid through the system at a certain rate. This
pressure has to be high enough to overcome the resistance of the system, which is also
called head. The total head is the sum of static head and friction head
a) Static head
Static head is the difference in height between the source and destination of the pumpedLiquid Static head is independent of the static head at a certain pressure depends on the
weight of the liquid and can be calculated with this equation
http://en.wikipedia.org/wiki/Liquidhttp://en.wikipedia.org/wiki/Gashttp://en.wikipedia.org/wiki/Slurryhttp://en.wikipedia.org/wiki/Slurryhttp://en.wikipedia.org/wiki/Gashttp://en.wikipedia.org/wiki/Liquid8/2/2019 Hossam Pumps
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Static head consists of :
Static suction head (hS): resulting from lifting the liquid relative to the pump center line.
The hS is positive if the liquid level is above pump centerline, and negative if the liquid
Level is below pump centerline (also called suction lift)
Static discharge head (hd): the vertical distance between the pump centerline and the
Surface of the liquid in the destination tank .
b) Friction head (hf)
This is the loss needed to overcome that is caused by the resistance to flow in the pipe and
fittings. It is dependent on size, condition and type of pipe, number and type of pipe fittings,
flow rate, and nature of the liquid. The friction head is proportional to the square of the flow
rate as shown in figure 3. A closed loop circulating system only exhibits friction head (i.e.not
static head).
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2. TYPE OF PUMPS
This section describes the various types of pumps. Pumps come in a variety of sizes for aWide range of applications. They can be classified according to their basic operatingprincipleAs dynamic or positive displacement pumps (Figure 7).
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In principle, any liquid can be handled by any of the pump designs. Where different pump
designs could be used, the centrifugal pump is generally the most economical followed by
rotary and reciprocating pumps. Although, positive displacement pumps are generally more
efficient than centrifugal pumps, the benefit of higher efficiency tends to be offset by
increased maintenance costs
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2.1. Positive displacement pumps
Positive displacement pumps are distinguished by the way they operate: liquid is taken from
one end and positively discharged at the other end for every revolution. Positive
displacement pumps are widely used for pumping fluids other than water, mostly viscous
fluids
Positive displacement pumps are further classified based upon the mode of displacement:
Reciprocating pump
if the displacement is by reciprocation of a piston plunger. Reciprocating pumps are usedonly for pumping viscous liquids and oil wells
Rotary pumps
if the displacement is by rotary action of a gear, cam or vanes in a chamber
of diaphragm in a fixed casing.
Rotary pumps are further classified such as internal gear,
external gear, lobe and slide vane etc. These pumps are used for special services with
particular conditions existing in industrial sites
2.2 Dynamic pumps
Dynamic pumps are also characterized by their mode of operation: a rotating impeller
Converts kinetic energy into pressure or velocity that is needed to pump the fluid.
There are two types of dynamic pumps:
Centrifugal pumps are the most common pumps used for pumping water in industrial
Applications. Typically, more than 75% of the pumps installed in an industry are
Centrifugal pumps. For this reason, this pump is further described below.
Special effect pumps are particularly used for specialized conditions at an industrial site
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2.2.1 How a centrifugal pump works
A centrifugal pump is one of the simplest pieces of equipment in any process plant. Figure 8
Shows how this type of pump operates :
Liquid is forced into an impeller either by atmospheric pressure, or in case of a jet pump
By artificial pressure.
The vanes of impeller pass kinetic energy to the liquid, thereby causing the liquid to rotate
. The liquid leaves the impeller at high velocity.
The impeller is surrounded by a volute casing or in case of a turbine pumps a stationary
Diffuser ring. The volute or stationary diffuser ring converts the kinetic energy into pressure
energy
.
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2.2.2 Components of a centrifugal pump
The main components of a centrifugal pump are shown in Figure 9 and described below
Rotating components : an impeller coupled to a shaft
Stationary components : casing, casing cover, and bearings
a) Impeller
n impeller is a circular metallic disc with a built-in passage for the flow of fluid. Impellers
are generally made of bronze, polycarbonate, cast iron or stainless steel, but other materials
are also used. As the performance of the pump depends on the type of impeller, it is
important to select a suitable design and to maintain the impeller in good condition.
The number of impellers determines the number of stages of the pump. A single stage pump
has one impeller and is best suited for low head (= pressure) service. A two-stage pump has
two impellers in series for medium head service. A multi-stage pump has three or more
impellers in series for high head service.
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Impellers can be classified on the basis of:
Major direction of flow from the rotation axis: radial flow, axial flow, mixed flow
Suction type : single suction and double suction
b) Shaft
The shaft transfers the torque from the motor to the impeller during the startup and operation
of the pump.
c) Casing
The main function of casing is to enclose the impeller at suction and delivery ends and
thereby form a pressure vessel. The pressure at suction end may be as little as one-tenth of
atmospheric pressure and at delivery end may be twenty times the atmospheric pressure in a
single-stage pump. For multi-stage pumps the pressure difference is much higher. The casing
is designed to withstand at least twice this pressure to ensure a large enough safety margin
A second function of casing is to provide a supporting and bearing medium for the shaft and
impeller. Therefore the pump casing should be designed to
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1-Provide easy access to all parts of pump for inspection, maintenance and repair
2-Make the casing leak-proof by providing stuffing boxes
3-Connect the suction and delivery pipes directly to the flanges
4-Be coupled easily to its prime mover (i.e. electric motor) without any power loss
3. ASSESSMENT OF PUMPS
The work performed by a pump is a function of the total head and of the weight of the liquid
pumped in a given time period. Pump shaft power (Ps) is the actual horsepower delivered to
the pump shaft, and can be calculated as follows:
Pump output, water horsepower or hydraulic horsepower (hp) is the liquid horsepowerDelivered by the pump, and can be calculated as follows
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Impulse pumps- 2
Impulse pumps use pressure created by gas (usually air). In some impulse pumps the gastrapped in the liquid (usually water), is released and accumulated somewhere in the pump,creating a pressure which can push part of the liquid upwards. Impulse pumps include
Hydraulic ram pumps - uses pressure built up internally from released gas in liquid flow .
Purser pumps - run with natural resources, by kinetic energy only.
Airlift pumps - run on air inserted into pipe, pushing up the water, when bubbles move
upward, or on pressure inside pipe pushing water up .
Hydraulic ram pumps
A hydraulic ram is a water pump powered by hydropower.
It functions as a hydraulic transformer that takes in water at one "hydraulic head" (pressure)
and 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 allows a portion of the input water that
powers the pump to be lifted to a point higher than where the water originally started.
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
3-Velocity pumps
Rot dynamic pumps (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
can be explained by the First law of thermodynamics or more specifically by Bernoulli's
principle.
http://en.wikipedia.org/wiki/Hydraulic_ramhttp://en.wikipedia.org/wiki/Pulser_pumphttp://en.wikipedia.org/wiki/Pulser_pumphttp://en.wikipedia.org/wiki/Airlift_pumphttp://en.wikipedia.org/wiki/Hydraulic_ramhttp://en.wikipedia.org/wiki/Water_hammerhttp://en.wikipedia.org/wiki/Rotodynamic_pumphttp://en.wikipedia.org/wiki/Kinetic_energyhttp://en.wikipedia.org/wiki/Kinetic_energyhttp://en.wikipedia.org/wiki/First_law_of_thermodynamicshttp://en.wikipedia.org/wiki/Bernoulli%27s_principlehttp://en.wikipedia.org/wiki/Bernoulli%27s_principlehttp://en.wikipedia.org/wiki/Bernoulli%27s_principlehttp://en.wikipedia.org/wiki/Bernoulli%27s_principlehttp://en.wikipedia.org/wiki/First_law_of_thermodynamicshttp://en.wikipedia.org/wiki/Kinetic_energyhttp://en.wikipedia.org/wiki/Kinetic_energyhttp://en.wikipedia.org/wiki/Rotodynamic_pumphttp://en.wikipedia.org/wiki/Water_hammerhttp://en.wikipedia.org/wiki/Hydraulic_ramhttp://en.wikipedia.org/wiki/Airlift_pumphttp://en.wikipedia.org/wiki/Pulser_pumphttp://en.wikipedia.org/wiki/Hydraulic_ram8/2/2019 Hossam Pumps
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These types of pumps have a number of characteristic
1. Continuous energy
2. Conversion of added energy to increase in kinetic energy (increase in velocity)
3. Conversion of increased velocity (kinetic energy) to an increase in pressure head
One practical difference between dynamic and positive displacement pumps is their
ability to operate under closed valve conditions. Positive displacement pumps physically
displace the fluid; hence closing a valve downstream of a positive displacement pump
will result in a continual build up in pressure resulting in mechanical failure of either
pipeline or pump. Dynamic pumps differ in that they can be safely operated under closed
valve conditions (for short periods of time) 4- Centrifugal pump
A centrifugal pump is a rot dynamic pump that uses a rotating impeller to increase thepressure and flow rate of a fluid. Centrifugal pumps are the most common type of pump usedto move liquids through a piping system. The fluid enters the pump impeller along or near tothe rotating axis and is accelerated by the impeller, flowing racially outward or axially into adiffuser or volute chamber, from where it exits into the downstream piping system.Centrifugal pumps are typically used for large discharge through smaller heads.
Centrifugal pumps are most often associated with the radial flow type. However, the term"centrifugal pump" can be used to describe all impeller type rot dynamic pumps includingthe radial, axial and mixed flow variations
http://en.wikipedia.org/wiki/Kinetic_energyhttp://en.wikipedia.org/wiki/Impellerhttp://en.wikipedia.org/wiki/Volutehttp://en.wikipedia.org/wiki/Volutehttp://en.wikipedia.org/wiki/Volutehttp://en.wikipedia.org/wiki/Volutehttp://en.wikipedia.org/wiki/Impellerhttp://en.wikipedia.org/wiki/Kinetic_energy8/2/2019 Hossam Pumps
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Radial flow pumps
Often simply referred to as centrifugal pumps. The fluid enters along the axial plane, isaccelerated by the impeller and exits at right angles to the shaft (racially). Radial flow pumpsoperate at higher pressures and lower flow rates than axial and mixed flow pumps
Axial flow pumps
Axial flow pumps differ from radial flow in that the fluid enters and exits along the samedirection parallel to the rotating shaft. The fluid is not accelerated but instead "lifted" by theaction of the impeller. They may be likened to a propeller spinning in a length of tube. AxialFlow pumps operate at much lower pressures and higher flow rates than radial flow pumps
Mixed flow pumps
Mixed flow pumps, as the name suggests, function as a compromise between radial and axialflow pumps, the fluid experiences both radial acceleration and lift and exits the impellersomewhere between 0 90 degrees from the axial direction. As a consequence mixed flowpumps operate at higher pressures than axial flow pumps while delivering higher dischargesthan radial flow pumps. The exit angle of the flow dictates the pressure head-dischargecharacteristic in relation to radial and mixed flow
Educator-jet pumpThis uses a jet, often of steam, to create a low pressure. This low pressure sucks in fluid andpropels it into a higher pressure region
Gravity pumps
Gravity pumps include the siphon and Heron's fountain and there also important qanat or foggara
systems which simply use downhill flow to take water from far-underground aquifers in high areas toconsumers at lower elevations. The hydraulic ram is also sometimes referred to as a gravity pump
Steam pumps
Steam pumps have been for a long time mainly of historical interest. Theyinclude any type of pump powered by a steam engine and also pump suchas Savory's, the Pulsometer steam pump or the Steam injection pump .
Recently there has been a resurgence of interest in low power solar steampumps for use in smallholder irrigation in developing countries. Previously smallsteam engines have not been viable because of escalating inefficiencies as
http://en.wikipedia.org/wiki/Syphonhttp://en.wikipedia.org/wiki/Syphonhttp://en.wikipedia.org/wiki/Syphonhttp://en.wikipedia.org/wiki/Heron%27s_fountainhttp://en.wikipedia.org/wiki/Heron%27s_fountainhttp://en.wikipedia.org/wiki/Heron%27s_fountainhttp://en.wikipedia.org/wiki/Qanathttp://en.wikipedia.org/wiki/Qanathttp://en.wikipedia.org/wiki/Qanathttp://en.wikipedia.org/wiki/Hydraulic_ramhttp://en.wikipedia.org/wiki/Hydraulic_ramhttp://en.wikipedia.org/wiki/Steam_enginehttp://en.wikipedia.org/wiki/Pulsometer_steam_pumphttp://en.wikipedia.org/w/index.php?title=Steam_injection_pump&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Steam_injection_pump&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Steam_injection_pump&action=edit&redlink=1http://en.wikipedia.org/wiki/Pulsometer_steam_pumphttp://en.wikipedia.org/wiki/Steam_enginehttp://en.wikipedia.org/wiki/Hydraulic_ramhttp://en.wikipedia.org/wiki/Qanathttp://en.wikipedia.org/wiki/Heron%27s_fountainhttp://en.wikipedia.org/wiki/Syphon8/2/2019 Hossam Pumps
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Valve less pumps
Valve less pumping assists in fluid transport in various biomedical and engineering systems. In a
valve less pumping system, no valves are present to regulate the flow direction. The fluid pumping
efficiency of a valve less 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 hearts valves fail. Meanwhile,
the embryonic vertebrate heart begins pumping blood long before the development of discernable
chambers and valves. In microfluidics, valueless impedance pump have been fabricated, and are
expected to be particularly suitable for handling sensitive biofluids.
Applications
Pumps are used throughout society for a variety of purposes. Early applications include theuse of the windmill or watermill to pump water. Today, the pump is used for irrigation, watersupply , gasoline supply, air conditioning systems, refrigeration (usually called a compressor),chemical movement, sewage movement, flood control, marine services, etc.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 lowpressure, and from high volume to low volume .
Priming a pump
Liquid and slurry pumps can lose prime and this will require the pump to be primed by
rted. Loss of "prime" is usuallyadding liquid to the pump and inlet pipes to get the pump sta
due to ingestion of air into the pump. The clearances and displacement ratios in pumps usedfor liquids and other more viscous fluids cannot displace the air due to its lower density
Sealing multiphase pumping applicationsMultiphase pumping applications also referred to as tri-phase, have grown due to increasedoil drilling activity. In addition, the economics of multiphase production is attractive toupstream operations as it leads to simpler, smaller in-field installations, reduced equipmentcosts and improved production rates. In essence, the multiphase pump can accommodateall 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 onemassive pump.
http://en.wikipedia.org/w/index.php?title=Valveless_pumping&action=edit&redlink=1http://en.wikipedia.org/wiki/Impedance_pumphttp://en.wikipedia.org/wiki/Windmillhttp://en.wikipedia.org/wiki/Windmillhttp://en.wikipedia.org/wiki/Watermillhttp://en.wikipedia.org/wiki/Watermillhttp://en.wikipedia.org/wiki/Plumbinghttp://en.wikipedia.org/wiki/Plumbinghttp://en.wikipedia.org/wiki/Plumbinghttp://en.wikipedia.org/wiki/Air_conditioninghttp://en.wikipedia.org/wiki/Refrigerationhttp://en.wikipedia.org/wiki/Refrigerationhttp://en.wikipedia.org/wiki/Air_conditioninghttp://en.wikipedia.org/wiki/Plumbinghttp://en.wikipedia.org/wiki/Plumbinghttp://en.wikipedia.org/wiki/Watermillhttp://en.wikipedia.org/wiki/Windmillhttp://en.wikipedia.org/wiki/Impedance_pumphttp://en.wikipedia.org/w/index.php?title=Valveless_pumping&action=edit&redlink=18/2/2019 Hossam Pumps
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For midstream and upstream operations, multiphase pumps can be located onshore oroffshore and can be connected to single or multiple wellheads. Basically, multiphase pumpsare used to transport the untreated flow stream produced from oil wells to downstreamprocesses or gathering facilities. This means that the pump may handle a flow stream (wellstream) 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. Multiphasepumps are designed to operate under changing/fluctuating process conditions. Multiphasepumping also helps eliminate emissions of greenhouse gases as operators strive tominimize the flaring of gas and the venting of tanks where possible
References
1. Pump classifications. Fao.org. Retrieved on 2011-05-25.
2. Tanzania water blog - example of grass roots researcher telling about his study and work with the
rope pump in Africa.
3. Welcome to the Hydraulic Institute. Pumps.org. Retrieved on 2011-05-25.
4. Karassik, Igor J.; Messina, Joseph P.; Cooper, Paul; Heald, Charles C. (2001). Pump
Handbook (3rd ed.). New York: McGraw-Hill. ISBN 9781591243618.
5. Pump Statistics Should Shape Strategies. Mt-online.com (2008-10-01). Retrieved on 2011-05-25.6. Submersible slurry ?pumps in high demand. Engineeringnews.co.za. Retrieved on 2011-05-25.
7. Wiser, Goodenberger, Jim and Bob (November 1993). "Extended Life, Zero Emissions Seal for
Process Pumps". Rutledge. ISBN TRP 28017.
8. Hill, Donald Rout ledge (1996). A History of Engineering in
http://www.fao.org/docrep/010/ah810e/AH810E05.htm#5.3.1http://tanzaniawater.blogspot.com/2010/08/hi-its-cai.htmlhttp://www.pumps.org/content_detail_pumps.aspx?id=1768http://en.wikipedia.org/wiki/International_Standard_Book_Numberhttp://en.wikipedia.org/wiki/Special:BookSources/9781591243618http://www.mt-online.com/mt-rokstories-places-holder/73-october/839-pump-statistics-should-shape-strategies.htmlhttp://www.engineeringnews.co.za/article/submersible-slurry-pumps-in-high-demand-2006-10-06http://en.wikipedia.org/wiki/International_Standard_Book_Numberhttp://en.wikipedia.org/wiki/Special:BookSources/TRP_28017http://books.google.com/books?id=MqSXc5sGZJUC&pg=PA143&dq=Taccola+first+pistonhttp://books.google.com/books?id=MqSXc5sGZJUC&pg=PA143&dq=Taccola+first+pistonhttp://books.google.com/books?id=MqSXc5sGZJUC&pg=PA143&dq=Taccola+first+pistonhttp://en.wikipedia.org/wiki/Special:BookSources/TRP_28017http://en.wikipedia.org/wiki/International_Standard_Book_Numberhttp://www.engineeringnews.co.za/article/submersible-slurry-pumps-in-high-demand-2006-10-06http://www.mt-online.com/mt-rokstories-places-holder/73-october/839-pump-statistics-should-shape-strategies.htmlhttp://en.wikipedia.org/wiki/Special:BookSources/9781591243618http://en.wikipedia.org/wiki/International_Standard_Book_Numberhttp://www.pumps.org/content_detail_pumps.aspx?id=1768http://tanzaniawater.blogspot.com/2010/08/hi-its-cai.htmlhttp://www.fao.org/docrep/010/ah810e/AH810E05.htm#5.3.1