The document discusses pumps, motors, and hydraulic cylinders. It begins by introducing hydraulic pumps and describing the two main types: rotodynamic pumps (like centrifugal pumps) and reciprocating pumps. It then compares centrifugal and positive displacement (reciprocating) pumps, noting key differences in how they handle flow rate, pressure, viscosity, efficiency, and net positive suction head (NPSH). The document dives deeper into technical terms related to pumps like static pressure, pressure head, specific weight, and flow rate. It provides diagrams of components like centrifugal pumps and reciprocating pumps. In summary, the document provides an overview of hydraulic pump types and technical concepts as well as comparisons between centrifugal and reciprocating pump
Hydraulics is a branch of science which deals with hydraulic fluid. It is used in places where cleanliness is not a priority but requires huge power to perform tasks.
application:
1. Industrial: Plastic processing machineries, steel making and primary metal extraction applications, automated production lines, machine tool industries, paper industries, loaders, crushes, textile machineries, R & D equipment and robotic systems etc.
2 Mobile hydraulics: Tractors, irrigation system, earthmoving equipment, material handling equipment, commercial vehicles, tunnel boring equipment, rail equipment, building and construction machineries and drilling rigs etc.
3 Automobiles: It is used in the systems like breaks, shock absorbers, steering system, wind shield, lift and cleaning etc.
4 Marine applications: It mostly covers ocean going vessels, fishing boats and navel equipment.
5 Aerospace equipment: There are equipment and systems used for rudder control, landing gear, breaks, flight control and transmission etc. which are used in airplanes, rockets and spaceships.
HYDRAULIC POWER GENERATING AND UTILIZING SYSTEMS
Introduction to fluid power system - Hydraulic fluids - functions, types, properties, selection and application.
POWER GENERATING ELEMENTS: Pumps, classification, working of different pumps such as Gear, Vane, Piston (axial and radial), pump performance or characteristics, pump selection factors- simple Problems.
POWER UTILIZING ELEMENTS: Fluid Power Actuators: Linear hydraulic actuators – Types and construction of hydraulic cylinders – Single acting, Double acting, special cylinders like tandem, Rodless, Telescopic, Cushioning mechanism.
Hydraulic Motors, types – Gear, Vane, Piston (axial and radial) – performance of motors.
Hydraulics is a branch of science which deals with hydraulic fluid. It is used in places where cleanliness is not a priority but requires huge power to perform tasks.
application:
1. Industrial: Plastic processing machineries, steel making and primary metal extraction applications, automated production lines, machine tool industries, paper industries, loaders, crushes, textile machineries, R & D equipment and robotic systems etc.
2 Mobile hydraulics: Tractors, irrigation system, earthmoving equipment, material handling equipment, commercial vehicles, tunnel boring equipment, rail equipment, building and construction machineries and drilling rigs etc.
3 Automobiles: It is used in the systems like breaks, shock absorbers, steering system, wind shield, lift and cleaning etc.
4 Marine applications: It mostly covers ocean going vessels, fishing boats and navel equipment.
5 Aerospace equipment: There are equipment and systems used for rudder control, landing gear, breaks, flight control and transmission etc. which are used in airplanes, rockets and spaceships.
HYDRAULIC POWER GENERATING AND UTILIZING SYSTEMS
Introduction to fluid power system - Hydraulic fluids - functions, types, properties, selection and application.
POWER GENERATING ELEMENTS: Pumps, classification, working of different pumps such as Gear, Vane, Piston (axial and radial), pump performance or characteristics, pump selection factors- simple Problems.
POWER UTILIZING ELEMENTS: Fluid Power Actuators: Linear hydraulic actuators – Types and construction of hydraulic cylinders – Single acting, Double acting, special cylinders like tandem, Rodless, Telescopic, Cushioning mechanism.
Hydraulic Motors, types – Gear, Vane, Piston (axial and radial) – performance of motors.
the presentation includes basic ideas about water pumps, various terminology generally used for the pumps, classification of pumps and ideas about the types its construction and working
Simple description about gas turbine. Where you are going to know about its classification,advantages and disadvantages also.Here also you can find-out where it is actually usages.
Hydraulic Filters are used to keep the contaminants away from the system and avoid mechanical failures. Fleetguard products cater to high, low and medium pressure hydraulic systems to protect industrial machinery and equipments.
For more details visit: https://www.fleetguard-filtrum.com/products/hydraulic-filtration/
In hydraulic and pneumatic systems flow control valves are necessary to vary the speed of actuator. Flow control valves are placed in between Actuator and Direction Control (DC) Valve
Compressors complete description and a well arranged slides for the topic. That's too the point and relevant slide share you are looking for! Hope you will find it easy to understand
Thank you!
Hydraulic Pumps, Motors and Actuators:
Construction, working principle and operation of rotary & reciprocating pumps like Gear, Vane, Generated-Rotor, Screw, Axial Piston, Radial Piston, Pump characteristics, Linear and Rotary Actuators, Hydrostatic Transmission Systems. Selection of components for applications
the presentation includes basic ideas about water pumps, various terminology generally used for the pumps, classification of pumps and ideas about the types its construction and working
Simple description about gas turbine. Where you are going to know about its classification,advantages and disadvantages also.Here also you can find-out where it is actually usages.
Hydraulic Filters are used to keep the contaminants away from the system and avoid mechanical failures. Fleetguard products cater to high, low and medium pressure hydraulic systems to protect industrial machinery and equipments.
For more details visit: https://www.fleetguard-filtrum.com/products/hydraulic-filtration/
In hydraulic and pneumatic systems flow control valves are necessary to vary the speed of actuator. Flow control valves are placed in between Actuator and Direction Control (DC) Valve
Compressors complete description and a well arranged slides for the topic. That's too the point and relevant slide share you are looking for! Hope you will find it easy to understand
Thank you!
Hydraulic Pumps, Motors and Actuators:
Construction, working principle and operation of rotary & reciprocating pumps like Gear, Vane, Generated-Rotor, Screw, Axial Piston, Radial Piston, Pump characteristics, Linear and Rotary Actuators, Hydrostatic Transmission Systems. Selection of components for applications
The working of the reciprocating pump is very simple and just like an I.C engine. First of all the piston has the function of providing the suction force, so that the liquid can be lift up or can be sucked in with great force. After that comes the compression part which will impart the required pressure energy to the fluids. In this part of the phase the piston have to do a great work so that the liquid can be compressed properly and its pressure can increased to the desired level. The inlet and the outlet valve open at a certain pressure which is set by the manufacturer.If the piston is of single acting type which means it can suck from one side and transmit to the same side only. But we can have the double reciprocating pump too which have the function of the giving suction and discharge simultaneously in each stroke. This pump can be used as the compressor also but for that we have to have a good valve arrangement which can operate with good frequency.Note: It is to be noted that the reciprocating pump is a positive displacements pump which means that the fluid can only move in one direction and can never reverse back. So due to this the pump is always started with outlet valve open otherwise the pressure will keep on building and this will lead to rupturing of the pipeline or even the pump itself. But if relief valve is fitted then this pressure will come down.
This report discusses about different types of tools that are required for cutting stones.
This is a study project that was done in 5th semester of B.Tech. for subject Manufacturing Process and Metallurgy.
Foundation of Computational Fluid Dynamics Parvesh TanejaParvesh Taneja
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Supervisory Control and Data Acquisition (SCADA) system for Greenhouse Farm w...Parvesh Taneja
Supervisory Control and Data Acquisition (SCADA) system for Greenhouse Farm with internet of things (I.o.T.) architecture.
Automation of a greenhouse using Raspberry Pi. Controlling Humidity,Temperature. Controlling everything remotely using your browser.
“Comparative and Competitive study of the corporate identity of the domestic ...Parvesh Taneja
“Comparative and Competitive study of the corporate identity of the domestic airlines and design a Facelift and image-refurbishment strategy for one of them. ”
TECHNICAL TRAINING MANUAL GENERAL FAMILIARIZATION COURSEDuvanRamosGarzon1
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The Single Aisle is the most advanced family aircraft in service today, with fly-by-wire flight controls.
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Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
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Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
Event Management System Vb Net Project Report.pdfKamal Acharya
In present era, the scopes of information technology growing with a very fast .We do not see any are untouched from this industry. The scope of information technology has become wider includes: Business and industry. Household Business, Communication, Education, Entertainment, Science, Medicine, Engineering, Distance Learning, Weather Forecasting. Carrier Searching and so on.
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Vaccine management system project report documentation..pdfKamal Acharya
The Division of Vaccine and Immunization is facing increasing difficulty monitoring vaccines and other commodities distribution once they have been distributed from the national stores. With the introduction of new vaccines, more challenges have been anticipated with this additions posing serious threat to the already over strained vaccine supply chain system in Kenya.
Explore the innovative world of trenchless pipe repair with our comprehensive guide, "The Benefits and Techniques of Trenchless Pipe Repair." This document delves into the modern methods of repairing underground pipes without the need for extensive excavation, highlighting the numerous advantages and the latest techniques used in the industry.
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Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
AKS UNIVERSITY Satna Final Year Project By OM Hardaha.pdf
Report on pumps
1. A study on Pumps, Motors &
Hydraulic Cylinders.
(STATIC TEST RIG FOR RECOIL SYSTEMOF ATAGS)
PARVESH TANEJA | REPORT | 26th
MARCH,2017
Figure 2.Pump Symbol
Figure 1. Gear Pumps (Manufacture by VBC Hydraulics, Gujarat)
2. PAGE 1
Contents
1.1 Introduction to Hydraulic Pump......................................................................................3
1.1.1 Rotodynamic Pump.....................................................................................................3
1.1.1.1 Centrifugal pump................................................................................................. 3
1.1.2 Reciprocating pump ....................................................................................................4
1.2 Selecting between Centrifugal or Positive Displacement Pumps (Merits & Demerits)............5
1.2.1 Flow Rate and Pressure Head.......................................................................................5
1.2.2 Capacity and Viscosity ................................................................................................5
1.2.3 Mechanical Efficiency.................................................................................................5
1.2.4 Net Positive Suction Head - NPSH...............................................................................5
1.3 Terms related to pumps .....................................................................................................6
1.3.1 Static pressure and pressure head .................................................................................6
1.3.1.1 Specific Weight.................................................................................................... 6
1.3.1.2 Static Pressure in a Fluid..................................................................................... 7
1.3.1.3 The Pressure Head............................................................................................... 8
1.3.2 Fluid Flow Rate ..........................................................................................................9
1.3.3 Pump Lift & Cavitation .............................................................................................10
1.3.3.1 Methods to Eliminate (Control) Cavitation.......................................................... 11
1.4 Pump Efficiencies...........................................................................................................11
1.4.1 Mechanical Efficiency of a Pump (ηm):................................................................... 11
1.4.2 Volumetric Efficiency of a Pump (ηv):.................................................................... 11
1.4.3 Overall Efficiency of a Pump (ηo):......................................................................... 12
1.5 Pump Selection...............................................................................................................12
Classification of different types of pumps...............................................................................13
3. PAGE 2
List of Figures
Figure 1. Gear Pumps (Manufacture by VBC Hydraulics, Gujarat) ............................................0
Figure 2.Pump Symbol ...........................................................................................................0
Figure 3.Centrifugal Pump ......................................................................................................3
Figure 4. Reciprocating or positive displacement pump.............................................................4
Figure 5. Gauge Pressure.........................................................................................................8
Figure 6. Flow Rate (Volume) .................................................................................................9
Figure 7. Pump Lift ..............................................................................................................10
Figure 8. Classification of different types of pumps ................................................................13
4. PAGE 3
1.1 Introduction to Hydraulic Pump
The combined pumping and driving motor unit is known as hydraulic pump. The hydraulic pump
takes hydraulic fluid (mostly some oil) from the storage tank and delivers it to the rest of the
hydraulic circuit. In general, the speed of pump is constant and the pump delivers an equal volume
of oil in each revolution. The amount and direction of fluid flow is controlled by some external
mechanisms. In some cases,the hydraulic pump itself is operated by a servo controlled motor but
it makes the system complex. The hydraulic pumps are characterized by its flow rate capacity,
power consumption, drive speed, pressure delivered at the outlet and efficiency of the pump. The
pumps are not 100% efficient. The efficiency of a pump can be specified by two ways. One is the
volumetric efficiency which is the ratio of actual volume of fluid delivered to the maximum
theoretical volume possible. Second is power efficiency which is the ratio of output hydraulic
power to the input mechanical/electrical power. The typical efficiency of pumps varies from 90-
98%.
Generally, hydraulic pumps can be of two types:
• Rotodynamic Pump (Centrifugal Pump)
• Reciprocating Pump
1.1.1 Rotodynamic Pump
They have a rotating element (called ‘impeller’) through which when the liquid passes,its angular
momentum changes which results in an increase of the pressure energy of the liquid. Thus, a
rotodynamic pump does not push the liquid as in the case of a positive displacement pump. The
most common example of a rotodynamic pump is centrifugal pumps.
1.1.1.1 Centrifugal pump
Centrifugal pump uses rotational kinetic energy to deliver the fluid. The rotational energy typically
comes from an engine or electric motor. The fluid enters the pump impeller along or near to the
rotating axis, accelerates in the propeller and flung out to the periphery by centrifugal force as
shown in figure 3. In centrifugal pump the delivery is not constant and
varies according to the outlet pressure. These pumps are not suitable for
high-pressure applications and are generally used for low-pressure and
high-volume flow applications. The maximum pressure capacity is
limited to 20-30 bars and the specific speed ranges from 500 to 10000.
Most of the centrifugal pumps are not self-priming and the pump casing
needs to be filled with liquid before the pump is started.
Figure 3.Centrifugal Pump
5. PAGE 4
1.1.2 Reciprocating pump
The reciprocating pump is a positive plunger pump. It is also known aspositive displacement pump
or piston pump. It is often used where relatively small quantity is to be handled and the delivery
pressure is quite large. The construction of these pumps is similar to the four-stroke engine as
shown in Fig.4 below. The crank is driven by some external rotating motor. The piston of pump
reciprocates due to crank rotation. The piston moves down in one half of crank rotation, the inlet
valve opens and fluid enters into the cylinder. In second half crank rotation the piston moves up,
the outlet valve opens and the fluid moves out from the outlet. At a time, only one valve is opened
and another is closed so there is no fluid leakage. Depending on the area of cylinder the pump
delivers constant volume of fluid in eachcycle independent to the pressure at the output port. These
are the pumps in which the liquid is sucked and then it is actually pushed due to the thrust exerted
on it by a moving element which results in lifting the liquid to a desired height. As such the
discharge of liquid pumped by these pumps almost fully depends on the speed of the pump. The
most common example of the positive displacement pump is reciprocating pumps.
Figure 4. Reciprocating or positive displacement pump
6. PAGE 5
1.2 Selecting between Centrifugal or Positive Displacement Pumps (Merits & Demerits)
1.2.1 FlowRate and Pressure Head
The two types of pumps behave very differently regarding pressure head and flow rate:
The Centrifugal Pump has varying flow depending on the system pressure or head
The Positive Displacement Pump has more or less a constant flow regardless of the system
pressure or head. Positive Displacement pumps generally makes more pressure than
Centrifugal Pump's.
1.2.2 Capacity and Viscosity
Another major difference between the pump types is the effect of viscosity on capacity:
In a Centrifugal Pump the flow is reduced when the viscosity is increased
In a Positive Displacement Pump the flow is increased when viscosity is increased
Liquids with high viscosity fills the clearances of Positive Displacement Pumps causing higher
volumetric efficiencies and Positive Displacement Pumps are better suited for higher viscosity
applications. A Centrifugal Pump becomes very inefficient at even modest viscosity.
1.2.3 Mechanical Efficiency
The pumps behaves different considering mechanical efficiency as well.
Changing the system pressure or head has little or no effect on the flow rate in a Positive
Displacement Pump
Changing the system pressure or head may have a dramatic effect on the flow rate in a
Centrifugal Pump
1.2.4 Net Positive Suction Head - NPSH
Another consideration is the Net Positive Suction Head - NPSH.
In a Centrifugal Pump, NPSH varies as a function of flow determined by pressure
In a Positive Displacement Pump, NPSH varies as a function of flow determined by speed.
Reducing the speed of the Positive Displacement Pump pump, reduces the NPSH
7. PAGE 6
1.3 Terms related to pumps
1.3.1 Static pressure and pressure head
Pressure indicates the normal force per unit area at a given point acting on a given plane. Since
there is no shearing stresses present in a fluid at rest - the pressure in a fluid is independent of
direction.
For fluids - liquids or gases - at rest the pressure gradient in the vertical direction depends only on
the specific weight of the fluid.
How pressure changes with elevation can be expressed as
dp = - γ dz (1)
where
dp = change in pressure
dz = change in height
γ = specific weight
The pressure gradient in vertical direction is negative - the pressure decrease upwards.
1.3.1.1 Specific Weight
Specific Weight can be expressed as:
γ = ρ g (2)
where
γ = specific weight
g = acceleration of gravity (9.81 m/s2, 32.174 ft/s2)
ρ = Density
In general, the specific weight - γ - is constant for fluids. For gases, the specific weight - γ
- varies with elevation.
The pressure exerted by a static fluid depends only upon
the depth of the fluid
the density of the fluid
8. PAGE 7
the acceleration of gravity
1.3.1.2 Static Pressure in a Fluid
For an incompressible fluid - as a liquid - the pressure difference between two elevations
can be expressed as:
p2 - p1 = - γ (z2 - z1) (3)
Where
p2 = pressure at level 2
p1 = pressure at level 1
z2 = level 2
z1 = level 1
(3) can be transformed to:
p1 - p2 = γ (z2 - z1) (4)
or
p1 - p2 = γ h (5)
where
h = z2 - z1 difference in elevation - the depth down from location z2.
or
p1 = γ h + p2 (6)
Example -Pressure ina Fluid
Pressure at water depth of 10 m can be calculated as:
p1 = γ h + p2
= (1000 kg/m3) (9.81 m/s2) (10 m) + (101.3 kPa)
= (98100 kg/ms2 or Pa) + (101300 Pa)
1 atm = 101 kPa = 14.7 psi
9. PAGE 8
= 199.4 kPa
where
ρ = 1000 kg/m3
g = 9.81 m/s2
p2 = pressure at surface level = atmospheric pressure = 101.3 kPa
The gauge pressure can be calculated
by setting p2 = 0
p1 = γ h + p2
= (1000 kg/m3) (9.81 m/s2) (10 m)
= 98.1 kPa
1.3.1.3 The Pressure Head
(6) can be transformed to:
h = (p2 - p1) / γ (7)
h express the pressure head - the height of a column of fluid of specific weight - γ -
required to give a pressure difference of (p2 - p1).
Example -Pressure Head
A pressure difference of 5 psi (lbf/in2) is equivalent to
(5 lbf/in2) (12 in/ft) (12 in/ft) / (62.4 lb/ft3)
= 11.6 ft of water
(5 lbf/in2) (12 in/ft) (12 in/ft) / (847 lb/ft3)
= 0.85 ft of mercury
Figure 5. Gauge Pressure
10. PAGE 9
1.3.2 Fluid FlowRate
The volume flow rate Q of a fluid is defined to be the volume of fluid that is passing through a
given cross sectional area per unit time.
Figure 6. Flow Rate (Volume)
Since volume flow rate measures the amount of volume that passes through an area per unit time,
the equation for the volume flow rate looks like this:
𝑄 =
𝑉
𝑡
=
𝑉𝑜𝑙𝑢𝑚𝑒
𝑡𝑖𝑚𝑒
In S.I. units (International System of Units),Volume flow rate has units of meters cubed per
second (m3
/sec ), it tells you the number of cubic meters of fluid that flows per second.
11. PAGE 10
1.3.3 Pump Lift & Cavitation
In general, the pump is placed over the fluid storage tank as shown in figure 5.1.5. The pump
creates a negative pressure at the inlet which causes fluid to be pushed up in the inlet pipe by
atmospheric pressure. It results in the fluid lift in the pump suction. The maximum pump lift can
be determined by atmospheric pressure and is given by pressure head as given below:
Pressure Head,P = ρgh
Theoretically, a pump lift of 8 m is possible but it is always lesser due to undesirable effects such
as cavitation. The cavitation is the formation of vapor cavities in a liquid. The cavities can be
small liquid-free zones ("bubbles" or "voids") formed due to partial vaporization of fluid (liquid).
These are usually generated when a liquid is subjected to rapid changes of pressure and the
pressure is relatively low. At higher pressure,the voids implode and can generate an intense
shockwave. Therefore,the cavitation should always be avoided. The cavitation can be reduced by
maintaining lower flow velocity at the inlet and therefore the inlet pipes have larger diameter than
the outlet pipes in a pump. The pump lift should be as small as possible to decrease the cavitation
and to increase the efficiency of the pump.
Figure 7. Pump Lift
12. PAGE 11
1.3.3.1 Methods to Eliminate (Control) Cavitation
Following are the methods to control cavitation:
1. Keep suction line velocities below 1.2 m/s.
2. Keep the pump inlet lines as short as possible.
3. Minimize the number of fittings in the inlet line.
4. Mount the pump as close as possible to the reservoir.
5. Use low-pressure drop inlet filters.
1.4 Pump Efficiencies
1.4.1 Mechanical Efficiency ofa Pump (ηm):
Mechanical efficiency of a pump (ηm) is the ratio of theoretical power that must be supplied
to operate the pump to the actual power delivered to the pump.
Mechanical efficiency can be used to determine the power lost in bearings and other
moving parts of a pump. It determines the actual power that must be supplied to a pump.
1.4.2 Volumetric Efficiency ofa Pump (ηv):
Volumetric efficiency of a pump (ηv) is defined as the ratio of the actual flow rate
delivered by the pump to the theoretical flow rate (i.e., flow rate without any leakage)
that must be produced by the pump.
Volumetric efficiency can be used to determine the amount of liquid lost, due to leakage,
in a pump.
13. PAGE 12
1.4.3 Overall Efficiency ofa Pump (ηo):
Overall efficiency of a pump (ηo) is the ratio of the actual power output of a pump to the
actual power input to the pump. It is the efficiency that determines the overall energy loss
in a pump.
Overall efficiency is essentially a combination of volumetric efficiency and mechanical
efficiency. It is the product of volumetric efficiency and mechanical efficiency of a
pump.
Overall efficiency = Mechanical Efficiency × Volumetric Efficiency
ηo = ηm × ηv
1.5 Pump Selection
Following parameters should be kept in mind while selecting a pump:
1. Maximum operating pressure
2. Maximum delivery
3. Type of control
4. Pump drive speed
5. Type of fluid
6. Pump contamination tolerance
7. Pump noise
8. Size and weight of a pump
9. Pump efficiency
10. Cost
11. Availability and interchangeability
12. Maintenance and spares
.
14. PAGE 13
Classification of different types of pumps
Figure 8. Classification of different types of pumps