This document provides an overview of various types of pumps. It discusses displacement pumps, centrifugal pumps, and pumps that use electromagnetic force or mechanical impulse. It describes the characteristics, performance parameters, materials selection, and applications of centrifugal pumps and process pumps. Key points covered include the classification of pumps, measurement of pump performance, cavitation, net positive suction head, affinity laws, and the use of vertical and close-coupled pumps.
This document provides an overview of various hydraulic machines, including accumulators, intensifiers, presses, cranes, lifts, rams, couplings, torque converters, air lift pumps, and jet pumps. It describes the basic construction and working principles of each machine. For examples like accumulators, presses, cranes, and lifts, it provides illustrations and explanations of how they work to lift or move heavy loads using fluid power. The document aims to introduce these common hydraulic devices and their functions.
Fundamentals of pumps I Types and overview I Gaurav Singh RajputGaurav Singh Rajput
This document provides an overview of different types of pumps, including their basic functions and applications. It discusses positive displacement pumps, which displace a fixed amount of liquid with each cycle, and centrifugal pumps, which increase liquid velocity to convert it to pressure. Positive displacement pumps include reciprocating pumps like piston and diaphragm pumps, and rotary pumps like gear, lobe, screw, and vane pumps. Centrifugal pumps are high-flow pumps commonly used for water transportation. The document compares pump types and provides details on operation and examples of gear, lobe, screw, and vane rotary positive displacement pumps.
Pumps are mechanical devices that use kinetic energy to move fluids by decreasing pressure in the pump's suction and increasing pressure in the discharge. There are two main types of pumps: positive displacement pumps which move a fixed volume of fluid with each cycle, and centrifugal pumps which use an impeller to accelerate fluid and increase pressure. Common industrial pumps include centrifugal pumps like axial flow, mixed flow, and vertical turbine pumps as well as positive displacement pumps like reciprocating, screw, and gear pumps. Pumps have components like a casing, impeller, shaft, and seals and are classified according to their method of moving fluid.
Steam jet ejectors provide vacuum using high-pressure steam as the motive fluid, requiring no external power source. They have no moving parts, making them reliable and easy to maintain. Ejectors work by accelerating steam through a converging-diverging nozzle, which entrains the suction fluid and recompresses it at an intermediate pressure through a diffuser. Ejectors can be single or multi-stage, with condensers used to improve efficiency, and are well-suited for applications that require vacuum where steam is readily available such as drying and distillation.
1) Pumps are devices that use mechanical energy to move fluids by increasing their velocity, pressure, or elevation. There are two main types - positive displacement pumps which move a fixed volume of fluid, and dynamic pumps which develop high fluid velocity and convert it to pressure.
2) Positive displacement pumps include rotary pumps like gear, screw, lobe and vane pumps which move fluid from an inlet to outlet as a chamber rotates. Reciprocating pumps use pistons or plungers on an intake and discharge stroke.
3) Common dynamic pumps are centrifugal pumps which use an impeller and casing to discharge fluid at high velocity converted to pressure, and axial pumps which develop pressure via propeller action on
This document provides an overview of pumps and centrifugal pumps specifically. It begins with classifications of pumps, including rotodynamic, reciprocating, and rotary positive displacement pumps. It then focuses on centrifugal pumps, describing their main components like the impeller and casing. Centrifugal pumps are further classified based on flow direction and head. The working principle is explained using velocity diagrams and equations for pressure developed. Hydraulic analysis defines terms like static head and manometric head. Energy transfer in the impeller and pump efficiencies are also covered.
This document provides information on various types of pumps and piping systems. It describes the main types of pumps as centrifugal, rotary, reciprocating, and deep well pumps. It also discusses the classification and basic operating principles of centrifugal and reciprocating pumps. Additionally, it covers topics such as pipe sizes, fittings, valves, head losses, cavitation, affinity laws, and equations for calculating pump parameters.
This document provides an overview of various hydraulic machines, including accumulators, intensifiers, presses, cranes, lifts, rams, couplings, torque converters, air lift pumps, and jet pumps. It describes the basic construction and working principles of each machine. For examples like accumulators, presses, cranes, and lifts, it provides illustrations and explanations of how they work to lift or move heavy loads using fluid power. The document aims to introduce these common hydraulic devices and their functions.
Fundamentals of pumps I Types and overview I Gaurav Singh RajputGaurav Singh Rajput
This document provides an overview of different types of pumps, including their basic functions and applications. It discusses positive displacement pumps, which displace a fixed amount of liquid with each cycle, and centrifugal pumps, which increase liquid velocity to convert it to pressure. Positive displacement pumps include reciprocating pumps like piston and diaphragm pumps, and rotary pumps like gear, lobe, screw, and vane pumps. Centrifugal pumps are high-flow pumps commonly used for water transportation. The document compares pump types and provides details on operation and examples of gear, lobe, screw, and vane rotary positive displacement pumps.
Pumps are mechanical devices that use kinetic energy to move fluids by decreasing pressure in the pump's suction and increasing pressure in the discharge. There are two main types of pumps: positive displacement pumps which move a fixed volume of fluid with each cycle, and centrifugal pumps which use an impeller to accelerate fluid and increase pressure. Common industrial pumps include centrifugal pumps like axial flow, mixed flow, and vertical turbine pumps as well as positive displacement pumps like reciprocating, screw, and gear pumps. Pumps have components like a casing, impeller, shaft, and seals and are classified according to their method of moving fluid.
Steam jet ejectors provide vacuum using high-pressure steam as the motive fluid, requiring no external power source. They have no moving parts, making them reliable and easy to maintain. Ejectors work by accelerating steam through a converging-diverging nozzle, which entrains the suction fluid and recompresses it at an intermediate pressure through a diffuser. Ejectors can be single or multi-stage, with condensers used to improve efficiency, and are well-suited for applications that require vacuum where steam is readily available such as drying and distillation.
1) Pumps are devices that use mechanical energy to move fluids by increasing their velocity, pressure, or elevation. There are two main types - positive displacement pumps which move a fixed volume of fluid, and dynamic pumps which develop high fluid velocity and convert it to pressure.
2) Positive displacement pumps include rotary pumps like gear, screw, lobe and vane pumps which move fluid from an inlet to outlet as a chamber rotates. Reciprocating pumps use pistons or plungers on an intake and discharge stroke.
3) Common dynamic pumps are centrifugal pumps which use an impeller and casing to discharge fluid at high velocity converted to pressure, and axial pumps which develop pressure via propeller action on
This document provides an overview of pumps and centrifugal pumps specifically. It begins with classifications of pumps, including rotodynamic, reciprocating, and rotary positive displacement pumps. It then focuses on centrifugal pumps, describing their main components like the impeller and casing. Centrifugal pumps are further classified based on flow direction and head. The working principle is explained using velocity diagrams and equations for pressure developed. Hydraulic analysis defines terms like static head and manometric head. Energy transfer in the impeller and pump efficiencies are also covered.
This document provides information on various types of pumps and piping systems. It describes the main types of pumps as centrifugal, rotary, reciprocating, and deep well pumps. It also discusses the classification and basic operating principles of centrifugal and reciprocating pumps. Additionally, it covers topics such as pipe sizes, fittings, valves, head losses, cavitation, affinity laws, and equations for calculating pump parameters.
Glossary of Pumping terms + Pumps Industry TerminologyMarch Pump
This document provides definitions for over 100 pumping and pump industry terms. It covers terms related to centrifugal pumps, mechanical seals, pump components, pump installation, and pump performance metrics. Key terms defined include net positive suction head (NPSH), best efficiency point (BEP), impeller, stuffing box, volute, and mechanical seal.
Different Centrifugal Pump Types and Their ApplicationsJay Khodiyar Pumps
A centrifugal pump is commonly used for transporting fluid in various industries by converting rotational energy into kinetic energy generated from impellers.
This document discusses water pumps, including their definition, classification, components, and operation. It describes how pumps work to convert mechanical energy into hydraulic energy to move water from lower to higher points. Pumps are classified as either turbo-hydraulic (centrifugal or positive displacement). Centrifugal pumps are the most common and their components and operation are explained in detail. Key concepts discussed include pump efficiency, cavitation, net positive suction head (NPSH), and selecting the appropriate pump based on system characteristics.
Basics Fundamentals and working Principle of Centrifugal Pump.SHASHI BHUSHAN
Basics Fundamentals and working Principle of Centrifugal Pump. Centrifugal pumps are the rotodynamic machines that convert mechanical energy of shaft into kinetic and pressure energy of Fluid which may be used to raise the level of fluid. A centrifugal pump is named so, because the energy added by the impeller to the fluid is largely due to centrifugal effects.
This document discusses various types of pumps used to move water from lower to higher points. It describes centrifugal pumps, which use centrifugal force to move water radially outward, and positive displacement pumps like screw and reciprocating pumps. Key parts of centrifugal pumps are identified, including the impeller, casing, suction pipe, and delivery pipe. Concepts discussed include total dynamic head, pump efficiency, cavitation, net positive suction head, and the process of selecting a pump by matching its characteristic curve to the system curve.
The document summarizes Ruhrpumpen's horizontal turbine pump (HTP) system. The HTP uses a multistage centrifugal pump configuration mounted on a rigid skid with an electric motor. It offers high efficiencies to reduce operating costs and is a low maintenance design. The HTP can accommodate flow rates from 150 to 120,000 barrels per day and pressures up to 6,000 psi for applications in oil & gas, mining, and general industries.
Hydraulic pumps convert mechanical energy into hydraulic energy by drawing in hydraulic fluid and pressurizing it. The two main types are dynamic pumps and positive displacement pumps. Positive displacement pumps are universally used in hydraulic systems as they can generate high pressures and are well-suited to overcoming system resistances. Common positive displacement pump designs include gear pumps and piston pumps.
Energy conservation related to pumps used in thermal power stationsManohar Tatwawadi
The presentation discusses about the conservation of energy in pumps and pumping stations as whole in Thermal Power Stations.The pumps efficiency is also discussed in details, how to calculate and the steps to increase efficiency of pumps as well as pumping stations.
This document provides an overview of centrifugal pumps and reciprocating pumps. It defines key components of centrifugal pumps like impellers and casings, and describes how they work by imparting centrifugal force to increase fluid pressure. It also defines important pump parameters like head, efficiency, specific speed, and NPSH. Cavitation in pumps and methods to prevent it are explained. Performance curves for pumps are introduced. Finally, the working principle and equations for reciprocating pumps are outlined.
The document provides information about Dunham-Bush WCFX water-cooled rotary screw water chillers. It summarizes their key features and specifications, including:
- They are available in 23 models from 57 to 508 cooling tons.
- They use hermetic screw compressors in a vertical design for reliability.
- They have flooded evaporators and removable water-cooled condensers for easy serviceability.
- Advanced microcomputer controls monitor operations and protective functions.
This document provides an overview of radial piston pumps. It defines a radial piston pump as a type of hydraulic pump where the working pistons extend radially from a central drive shaft. The document discusses the construction, working, properties, advantages, and applications of radial piston pumps. It notes that radial piston pumps can produce smooth flow under extreme pressure and are commonly used in machine tools, hydraulic systems, and the automotive industry.
The document describes a major project submitted by six students to their lecturer on a pedal powered water pump. It includes a title page, declarations by the students and lecturer, acknowledgements, and a table of contents outlining what will be covered in the project report. Some of the key components to be discussed include the hand pump, pedal arrangement, rod, ball valve, pipe fittings and pressure gauges. The overall aim of the project is to design and build a water pump that can be operated by pedal power.
This document provides information about centrifugal pumps. It was presented by 4 students. The document defines a pump as a machine that converts mechanical energy into fluid energy. There are two main types of pumps: rotodynamic (centrifugal) pumps and positive displacement pumps. Centrifugal pumps have a rotating impeller that sweeps liquid outwards, converting velocity energy to pressure energy. Positive displacement pumps trap liquid between moving components like gears or lobes to move it from low to high pressure. The document discusses the key components of centrifugal pumps like the casing, impeller types, and cavitation. It also defines important pump specifications such as head, efficiency, and discharge calculations.
The document discusses the selection and application of pumps. It begins by defining different types of pumps, including piston pumps, plunger pumps, diaphragm pumps, and centrifugal pumps. It then discusses key considerations for pump selection like fluid characteristics, pressure requirements, and space availability. The document also covers pump performance concepts like net positive suction head (NPSH), total dynamic head, brake horsepower calculations, and affinity laws relating pump parameters like flow, head, and rpm. Overall, the document provides an overview of different pump types and the important technical factors to examine when choosing a pump for a given application.
Positive displacement pumps work by trapping a fixed amount of fluid and forcing it into the discharge pipe. There are two main types: reciprocating pumps which use pistons and rotary motion to pump fluid, and linear pumps which use diaphragms or plungers to linearly displace fluid. Reciprocating pumps can vary the flow within each revolution while linear pumps provide nearly constant flow over a wide pressure range. Common applications of positive displacement pumps include agriculture, chemical processes, desalination, mining, and oil and gas industries.
Positive displacement pumps work by trapping a fixed amount of fluid and forcing it to discharge. There are three main types: reciprocating pumps use pistons, diaphragm pumps use flexible diaphragms, and linear pumps use linear motion. Reciprocating pumps are commonly used for high pressure applications like well services. Diaphragm pumps are suitable for handling corrosive or abrasive liquids since only the diaphragm and valves contact the fluid. Positive displacement pumps can handle high viscosity liquids efficiently and are used widely in industries like oil and gas, mining, and more.
The document discusses centrifugal pumps, including their working mechanism, operation, advantages, and disadvantages. Centrifugal pumps use a rotating impeller to impart centrifugal force on liquid and increase pressure to pump water from a low point to a higher point. They are simple to operate but work best over a narrow range of conditions and cannot handle highly viscous liquids efficiently.
This 6 page document discusses flow through pipes and is authored by Gopalakrishnan.K and Vadakkinedath from Eloor East, Kerala, India. The document covers this topic across 6 pages but provides no other details about the content or analysis within each page.
This document provides a list of useful MS Word shortcut keys for exams and day-to-day work. It includes shortcuts for formatting text like bold, italics, underline, alignment and indentation. It also lists navigation shortcuts to move between documents, pages, lines and words. Common shortcuts are listed for editing text like copy, cut, paste, undo and redo. The shortcuts will help answer questions in competitive exams and make document preparation more efficient.
Glossary of Pumping terms + Pumps Industry TerminologyMarch Pump
This document provides definitions for over 100 pumping and pump industry terms. It covers terms related to centrifugal pumps, mechanical seals, pump components, pump installation, and pump performance metrics. Key terms defined include net positive suction head (NPSH), best efficiency point (BEP), impeller, stuffing box, volute, and mechanical seal.
Different Centrifugal Pump Types and Their ApplicationsJay Khodiyar Pumps
A centrifugal pump is commonly used for transporting fluid in various industries by converting rotational energy into kinetic energy generated from impellers.
This document discusses water pumps, including their definition, classification, components, and operation. It describes how pumps work to convert mechanical energy into hydraulic energy to move water from lower to higher points. Pumps are classified as either turbo-hydraulic (centrifugal or positive displacement). Centrifugal pumps are the most common and their components and operation are explained in detail. Key concepts discussed include pump efficiency, cavitation, net positive suction head (NPSH), and selecting the appropriate pump based on system characteristics.
Basics Fundamentals and working Principle of Centrifugal Pump.SHASHI BHUSHAN
Basics Fundamentals and working Principle of Centrifugal Pump. Centrifugal pumps are the rotodynamic machines that convert mechanical energy of shaft into kinetic and pressure energy of Fluid which may be used to raise the level of fluid. A centrifugal pump is named so, because the energy added by the impeller to the fluid is largely due to centrifugal effects.
This document discusses various types of pumps used to move water from lower to higher points. It describes centrifugal pumps, which use centrifugal force to move water radially outward, and positive displacement pumps like screw and reciprocating pumps. Key parts of centrifugal pumps are identified, including the impeller, casing, suction pipe, and delivery pipe. Concepts discussed include total dynamic head, pump efficiency, cavitation, net positive suction head, and the process of selecting a pump by matching its characteristic curve to the system curve.
The document summarizes Ruhrpumpen's horizontal turbine pump (HTP) system. The HTP uses a multistage centrifugal pump configuration mounted on a rigid skid with an electric motor. It offers high efficiencies to reduce operating costs and is a low maintenance design. The HTP can accommodate flow rates from 150 to 120,000 barrels per day and pressures up to 6,000 psi for applications in oil & gas, mining, and general industries.
Hydraulic pumps convert mechanical energy into hydraulic energy by drawing in hydraulic fluid and pressurizing it. The two main types are dynamic pumps and positive displacement pumps. Positive displacement pumps are universally used in hydraulic systems as they can generate high pressures and are well-suited to overcoming system resistances. Common positive displacement pump designs include gear pumps and piston pumps.
Energy conservation related to pumps used in thermal power stationsManohar Tatwawadi
The presentation discusses about the conservation of energy in pumps and pumping stations as whole in Thermal Power Stations.The pumps efficiency is also discussed in details, how to calculate and the steps to increase efficiency of pumps as well as pumping stations.
This document provides an overview of centrifugal pumps and reciprocating pumps. It defines key components of centrifugal pumps like impellers and casings, and describes how they work by imparting centrifugal force to increase fluid pressure. It also defines important pump parameters like head, efficiency, specific speed, and NPSH. Cavitation in pumps and methods to prevent it are explained. Performance curves for pumps are introduced. Finally, the working principle and equations for reciprocating pumps are outlined.
The document provides information about Dunham-Bush WCFX water-cooled rotary screw water chillers. It summarizes their key features and specifications, including:
- They are available in 23 models from 57 to 508 cooling tons.
- They use hermetic screw compressors in a vertical design for reliability.
- They have flooded evaporators and removable water-cooled condensers for easy serviceability.
- Advanced microcomputer controls monitor operations and protective functions.
This document provides an overview of radial piston pumps. It defines a radial piston pump as a type of hydraulic pump where the working pistons extend radially from a central drive shaft. The document discusses the construction, working, properties, advantages, and applications of radial piston pumps. It notes that radial piston pumps can produce smooth flow under extreme pressure and are commonly used in machine tools, hydraulic systems, and the automotive industry.
The document describes a major project submitted by six students to their lecturer on a pedal powered water pump. It includes a title page, declarations by the students and lecturer, acknowledgements, and a table of contents outlining what will be covered in the project report. Some of the key components to be discussed include the hand pump, pedal arrangement, rod, ball valve, pipe fittings and pressure gauges. The overall aim of the project is to design and build a water pump that can be operated by pedal power.
This document provides information about centrifugal pumps. It was presented by 4 students. The document defines a pump as a machine that converts mechanical energy into fluid energy. There are two main types of pumps: rotodynamic (centrifugal) pumps and positive displacement pumps. Centrifugal pumps have a rotating impeller that sweeps liquid outwards, converting velocity energy to pressure energy. Positive displacement pumps trap liquid between moving components like gears or lobes to move it from low to high pressure. The document discusses the key components of centrifugal pumps like the casing, impeller types, and cavitation. It also defines important pump specifications such as head, efficiency, and discharge calculations.
The document discusses the selection and application of pumps. It begins by defining different types of pumps, including piston pumps, plunger pumps, diaphragm pumps, and centrifugal pumps. It then discusses key considerations for pump selection like fluid characteristics, pressure requirements, and space availability. The document also covers pump performance concepts like net positive suction head (NPSH), total dynamic head, brake horsepower calculations, and affinity laws relating pump parameters like flow, head, and rpm. Overall, the document provides an overview of different pump types and the important technical factors to examine when choosing a pump for a given application.
Positive displacement pumps work by trapping a fixed amount of fluid and forcing it into the discharge pipe. There are two main types: reciprocating pumps which use pistons and rotary motion to pump fluid, and linear pumps which use diaphragms or plungers to linearly displace fluid. Reciprocating pumps can vary the flow within each revolution while linear pumps provide nearly constant flow over a wide pressure range. Common applications of positive displacement pumps include agriculture, chemical processes, desalination, mining, and oil and gas industries.
Positive displacement pumps work by trapping a fixed amount of fluid and forcing it to discharge. There are three main types: reciprocating pumps use pistons, diaphragm pumps use flexible diaphragms, and linear pumps use linear motion. Reciprocating pumps are commonly used for high pressure applications like well services. Diaphragm pumps are suitable for handling corrosive or abrasive liquids since only the diaphragm and valves contact the fluid. Positive displacement pumps can handle high viscosity liquids efficiently and are used widely in industries like oil and gas, mining, and more.
The document discusses centrifugal pumps, including their working mechanism, operation, advantages, and disadvantages. Centrifugal pumps use a rotating impeller to impart centrifugal force on liquid and increase pressure to pump water from a low point to a higher point. They are simple to operate but work best over a narrow range of conditions and cannot handle highly viscous liquids efficiently.
This 6 page document discusses flow through pipes and is authored by Gopalakrishnan.K and Vadakkinedath from Eloor East, Kerala, India. The document covers this topic across 6 pages but provides no other details about the content or analysis within each page.
This document provides a list of useful MS Word shortcut keys for exams and day-to-day work. It includes shortcuts for formatting text like bold, italics, underline, alignment and indentation. It also lists navigation shortcuts to move between documents, pages, lines and words. Common shortcuts are listed for editing text like copy, cut, paste, undo and redo. The shortcuts will help answer questions in competitive exams and make document preparation more efficient.
This document provides a list of keyboard shortcuts for Excel that help with navigating, selecting cells and ranges, formatting cells, and common editing tasks like copying, pasting, filling cells. Some key shortcuts include using Ctrl + arrows to select entire columns or rows, Ctrl + space to select entire columns, Shift + space for rows, and Alt + tab to switch between open programs. Function keys like F2, F7 and F12 perform actions like editing cells, spell checking, and saving files.
This document provides a summary of common shortcut keys in AutoCAD for 2D drawing, modifying objects, general navigation, 3D modeling, 3D modifying, and lighting/materials. Some of the most frequently used shortcuts include L for lines, E for erasing objects, AR for arraying objects, Z for zooming, and SHA for shading mode. The shortcuts allow users to draw and modify both 2D and 3D objects as well as navigate around drawings efficiently in AutoCAD.
The document discusses piping design and components. It covers piping materials like carbon steel, alloy steel and stainless steel. Key piping elements include pipes, fittings, flanges, valves, gaskets and bolting. Common piping components are described along with relevant standards for materials, dimensions and design considerations. Factors in pipe sizing and thickness calculation are also outlined.
The document discusses various topics related to refrigeration and air conditioning systems including:
1. Methods of refrigeration such as vapor compression, vapor absorption, thermoelectric, and magnetic refrigeration.
2. Key components like compressors, condensers, expansion devices, and evaporators.
3. Refrigeration cycle diagrams and concepts in the psychrometric chart.
4. Factors considered in air conditioning design like cooling, heating, humidity control, ventilation, and human comfort needs.
This document provides information on various types of turbines used in rotating equipment design. It discusses impulse and reaction turbines, and describes the basic mechanics and classifications of stages. Steam turbines are described in detail, including common types and configurations. Gas turbines are also covered, explaining the main components of compressors, combustors, and axial or radial flow turbines. Turbine performance parameters, controls, materials, and cooling techniques are summarized as well.
This document provides information on various types of material handling equipment used in industries. It begins with an overview of typical raw material and finished product handling flow diagrams. It then discusses different types of conveyors like screw conveyors, belt conveyors, vibrating conveyors, continuous-flow conveyors, flight conveyors, and pneumatic conveyors. Further sections cover storage bins, feeders, crushers and mills, screening equipment, rotary dryers, elevators, and silos. For each type of equipment, the document describes the basic working, common varieties used, and selection criteria based on the material properties.
Valves can be categorized based on their ends, materials, and pressure class. Common end types include screwed, socket weld, flanged, butt welded, and wafer. Common materials are cast iron, ductile iron, bronze, carbon steel, stainless steel, alloy steel, plastic, and glass. Pressure classes range from 150# to 4500#.
The document is a 54 page report authored by Gopalakrishnan.K of Vadakkinedath, Kerala dated October 30th, 2022. It discusses rotating equipment over 54 pages, with each page focusing on a different aspect or component of rotating equipment. The report provides detailed information and analysis of rotating equipment.
The document contains contact information for Gopalakrishnan in Kerala, India, followed by the repeated phrase "BEARING&LUBRICATION" over 30 lines. It concludes with "Thank you". The document appears to be advertising bearing and lubrication products or services without providing any further details.
The document appears to be a record from Piping & Mechanical dated October 30th, 2022 containing 31 entries of "PIPING & MECH." along with contact information for Gopalakrishnan.K in Vadakkinedath, Kerala at the beginning and a final "Thank You" entry at the end.
The document contains contact information for Gopalakrishnan.K who is located in Vadakkinedath, Eloor, Kerala and appears to work in the field of HE&HVAC (Heating, Ventilation and Air Conditioning). The document is primarily composed of the repeated acronym "HE&HVAC" and concludes by thanking the reader.
This document appears to be a letter from an individual named Gopalakrishnan.K who resides in Vadakkinedath, Eloor, Kerala. The document expresses thanks but does not provide any other details about the purpose or contents of the letter.
El documento proporciona instrucciones sobre la instalación, operación y solución de problemas de bombas y componentes de bombeo de la compañía PUMPS&COMP.S ubicada en Eloor, Kerala, India y dirigida por Gopalakrishnan.K y Vadakkinedath. Incluye secciones sobre instalación, operación, solución de problemas y agradecimientos.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive function. Exercise causes chemical changes in the brain that may help protect against mental illness and improve symptoms.
Design and optimization of ion propulsion dronebjmsejournal
Electric propulsion technology is widely used in many kinds of vehicles in recent years, and aircrafts are no exception. Technically, UAVs are electrically propelled but tend to produce a significant amount of noise and vibrations. Ion propulsion technology for drones is a potential solution to this problem. Ion propulsion technology is proven to be feasible in the earth’s atmosphere. The study presented in this article shows the design of EHD thrusters and power supply for ion propulsion drones along with performance optimization of high-voltage power supply for endurance in earth’s atmosphere.
Redefining brain tumor segmentation: a cutting-edge convolutional neural netw...IJECEIAES
Medical image analysis has witnessed significant advancements with deep learning techniques. In the domain of brain tumor segmentation, the ability to
precisely delineate tumor boundaries from magnetic resonance imaging (MRI)
scans holds profound implications for diagnosis. This study presents an ensemble convolutional neural network (CNN) with transfer learning, integrating
the state-of-the-art Deeplabv3+ architecture with the ResNet18 backbone. The
model is rigorously trained and evaluated, exhibiting remarkable performance
metrics, including an impressive global accuracy of 99.286%, a high-class accuracy of 82.191%, a mean intersection over union (IoU) of 79.900%, a weighted
IoU of 98.620%, and a Boundary F1 (BF) score of 83.303%. Notably, a detailed comparative analysis with existing methods showcases the superiority of
our proposed model. These findings underscore the model’s competence in precise brain tumor localization, underscoring its potential to revolutionize medical
image analysis and enhance healthcare outcomes. This research paves the way
for future exploration and optimization of advanced CNN models in medical
imaging, emphasizing addressing false positives and resource efficiency.
Batteries -Introduction – Types of Batteries – discharging and charging of battery - characteristics of battery –battery rating- various tests on battery- – Primary battery: silver button cell- Secondary battery :Ni-Cd battery-modern battery: lithium ion battery-maintenance of batteries-choices of batteries for electric vehicle applications.
Fuel Cells: Introduction- importance and classification of fuel cells - description, principle, components, applications of fuel cells: H2-O2 fuel cell, alkaline fuel cell, molten carbonate fuel cell and direct methanol fuel cells.
Rainfall intensity duration frequency curve statistical analysis and modeling...bijceesjournal
Using data from 41 years in Patna’ India’ the study’s goal is to analyze the trends of how often it rains on a weekly, seasonal, and annual basis (1981−2020). First, utilizing the intensity-duration-frequency (IDF) curve and the relationship by statistically analyzing rainfall’ the historical rainfall data set for Patna’ India’ during a 41 year period (1981−2020), was evaluated for its quality. Changes in the hydrologic cycle as a result of increased greenhouse gas emissions are expected to induce variations in the intensity, length, and frequency of precipitation events. One strategy to lessen vulnerability is to quantify probable changes and adapt to them. Techniques such as log-normal, normal, and Gumbel are used (EV-I). Distributions were created with durations of 1, 2, 3, 6, and 24 h and return times of 2, 5, 10, 25, and 100 years. There were also mathematical correlations discovered between rainfall and recurrence interval.
Findings: Based on findings, the Gumbel approach produced the highest intensity values, whereas the other approaches produced values that were close to each other. The data indicates that 461.9 mm of rain fell during the monsoon season’s 301st week. However, it was found that the 29th week had the greatest average rainfall, 92.6 mm. With 952.6 mm on average, the monsoon season saw the highest rainfall. Calculations revealed that the yearly rainfall averaged 1171.1 mm. Using Weibull’s method, the study was subsequently expanded to examine rainfall distribution at different recurrence intervals of 2, 5, 10, and 25 years. Rainfall and recurrence interval mathematical correlations were also developed. Further regression analysis revealed that short wave irrigation, wind direction, wind speed, pressure, relative humidity, and temperature all had a substantial influence on rainfall.
Originality and value: The results of the rainfall IDF curves can provide useful information to policymakers in making appropriate decisions in managing and minimizing floods in the study area.
Embedded machine learning-based road conditions and driving behavior monitoringIJECEIAES
Car accident rates have increased in recent years, resulting in losses in human lives, properties, and other financial costs. An embedded machine learning-based system is developed to address this critical issue. The system can monitor road conditions, detect driving patterns, and identify aggressive driving behaviors. The system is based on neural networks trained on a comprehensive dataset of driving events, driving styles, and road conditions. The system effectively detects potential risks and helps mitigate the frequency and impact of accidents. The primary goal is to ensure the safety of drivers and vehicles. Collecting data involved gathering information on three key road events: normal street and normal drive, speed bumps, circular yellow speed bumps, and three aggressive driving actions: sudden start, sudden stop, and sudden entry. The gathered data is processed and analyzed using a machine learning system designed for limited power and memory devices. The developed system resulted in 91.9% accuracy, 93.6% precision, and 92% recall. The achieved inference time on an Arduino Nano 33 BLE Sense with a 32-bit CPU running at 64 MHz is 34 ms and requires 2.6 kB peak RAM and 139.9 kB program flash memory, making it suitable for resource-constrained embedded systems.
Electric vehicle and photovoltaic advanced roles in enhancing the financial p...IJECEIAES
Climate change's impact on the planet forced the United Nations and governments to promote green energies and electric transportation. The deployments of photovoltaic (PV) and electric vehicle (EV) systems gained stronger momentum due to their numerous advantages over fossil fuel types. The advantages go beyond sustainability to reach financial support and stability. The work in this paper introduces the hybrid system between PV and EV to support industrial and commercial plants. This paper covers the theoretical framework of the proposed hybrid system including the required equation to complete the cost analysis when PV and EV are present. In addition, the proposed design diagram which sets the priorities and requirements of the system is presented. The proposed approach allows setup to advance their power stability, especially during power outages. The presented information supports researchers and plant owners to complete the necessary analysis while promoting the deployment of clean energy. The result of a case study that represents a dairy milk farmer supports the theoretical works and highlights its advanced benefits to existing plants. The short return on investment of the proposed approach supports the paper's novelty approach for the sustainable electrical system. In addition, the proposed system allows for an isolated power setup without the need for a transmission line which enhances the safety of the electrical network
Discover the latest insights on Data Driven Maintenance with our comprehensive webinar presentation. Learn about traditional maintenance challenges, the right approach to utilizing data, and the benefits of adopting a Data Driven Maintenance strategy. Explore real-world examples, industry best practices, and innovative solutions like FMECA and the D3M model. This presentation, led by expert Jules Oudmans, is essential for asset owners looking to optimize their maintenance processes and leverage digital technologies for improved efficiency and performance. Download now to stay ahead in the evolving maintenance landscape.
6. Displacement
Discharge of fluid from one vessel by partially or
completely displacing its internal volume with a
second fluid or by mechanical means
6
thinking beyond tomorrow
Displacement
Centrifugal force
7. Characteristics
They are adaptable to high pressure operations
The flow rate through the pump is variable
Mechanical consideration limit - maximum
throughput
The device are capable of efficient performance
at extremely low volume throughput rates
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8. Centrifugal force
Produce kinetic energy by the action of
centrifugal force converting energy into pressure
by efficiently reducing velocity of the flowing
fluid
Characteristics
Discharge is relatively free of pulsation
Mechanical design lends itself to high
throughputs
Efficient performance over a wide range of
pressures and capacity
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9. Axial-flow device
Combines the use of centrifugal force with
mechanical impulse to produce an increase in
pressure
Fluid travels roughly parallel to the shaft
through a series of alternately rotating and
stationary radial blades having airfoil cross
sections
Discharge pressure is a function of fluid density
Relatively small high-speed devices and less
costly.
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10. Electromagnetic force
When the fluid is an electrical conductor, it is
possible to impress an electromagnetic field
around the fluid conduit in such a way that a
driving force will cause flow
Transfer of momentum
Deceleration of one fluid (motivating fluid) in order
to transfer its momentum to a second fluid (pumped
fluid)
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11. Mechanical impulse
This when applied to fluids is usually combined
with one of the other means of imparting
motion
Measurement of performance
The product of the mass flow rate of fluid and the
total pressure differential
ie. Capacity x head
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12. Capacity
m3/hr for both liquids and gases (SI unit)
In U.S gal/min for liquids and ft3/min for gases
Multiply by density or specific gravity for mass
rate of flow
Total dynamic/ differential head
The total dynamic head H of a pump is the total
discharge head hd minus the total suction head hs.
I.e. H= hd - hs
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13. Total suction head
hs = hgs + atm + hvs
hgs of a gauge at the suction of a pump, negative
when gage pressure is less than atmospheric
pressure, barometer reading and velocity head
hvd
also
hs = hss - hfs
where hss = static suction head and hfs = suction
friction head.
hss is the vertical distance from the free surface to
the pump centerline plus the absolute pressure
at the liquid surface
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14. Total discharge head
hd = hgd + atm + hvd
discharge head hd
hgd gauge at the discharge
also
hd = hsd + hfd
static discharge head hsd is the vertical distance
from the free surface to the pump centerline
plus the absolute pressure at the liquid surface
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15. Total static head
hts = is the difference between discharge and
suction static heads.
Velocity: the quantity flowing past a given point in a
given time
Q = Av
Velocity head hv : This is the vertical distance by
which a body must fall to acquire the velocity ,
hv = v2/2g
Viscosity: Internal friction or the internal resistance
to relative motion of the fluid particles
Friction head (hf):The Pressure required to
overcome the resistance to flow in the pipe and
fittings
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16. Work performed in Pumping
Power output: is the product of the total
dynamic head and the mass of liquid pumped in
a given time
KW = HQρ/3.670 x105
Hp=ρQH/75
Power Input=Power Out put/ efficiency
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17. Cavitation
Whenever the pressure in a liquid drops below
the vapor pressure corresponding to its
temperature the liquid will vapourise. The
vapour bubbles will be carried along to a point
of higher pressure where they suddenly
collapse accompanied by metal removal
vibration, reduced flow, loss in efficiency and
noise. Cavitation occurs at pump inlet and
damage result in the pump suction and on the
impeller vanes near the inlet edges.
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18. NPSH required
Equivalent total head of liquid at the pump
centre line less the vapour pressure P.
Pump manufactures publishes curves relating to
NPSHR to capacity and speed for each pump.
NPSHR depends on the characteristics of the
liquid, the total head, the pump speed, the
capacity, the impeller design.
NPSH available (NPSHA)
Must be equal to or greater than NPSHR for the
desired capacity.
NPSHA= hss – hfs – P
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19. For an existing installation :
NPSHA = atm + hgs – P + hvs
Pump selection parameters
Liquid to be handled, total dynamic head,
suction and discharge heads, temperature,
viscosity, vapour pressure and specific gravity
Presence of solids in the liquid
Corrosion characteristics requiring special
materials of construction
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21. Material of construction
Dictated by consideration of corrosion, erosion,
personal safety and liquid contamination
When solids present
Dimensions of all internal passages are critical
Pockets and dead spots, areas where solids can
accumulate must be avoided
Flushing connection for continuous or
intermittent use should be provided
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22. Widely used in chemical industry
Capacities from 0.5 m3 /hr to 2 x 104 m3/hr and
heads from few meters to 48 Mpa
Simplicity, low first cost, uniform flow, small
floor space, low maintenance expense, quiet
operation and adaptability for using with motor
or turbine drive
Impeller consisting of number of blades either
open or shrouded mounted on a shaft that
projects outside the casing
Either horizontal or vertical
Centrifugal Pumps
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23. Open or semi open type impellers are used for
viscous liquids or suspended solids
With single suction or double suction
Casing is a chamber in which the impeller
rotates provided with inlet and outlet for liquids
Circular casing, volute casing and diffuser type
casings
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28. Similarity relationship/Affinity laws
Capacity (Q) is proportional to impeller rotational
speed
Head (h) varies as square of the impeller
rotational speed
Brake horse power (BHP) varies as cube of the
impeller rotational speed
Affinity laws
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29. Pump selection
Specific speed is a parameter that defines the
speed at which impellers of geometrically
similar design have to be run to discharge one
gallon per minute against a one foot head
Pumps with low specific speed have low
capacity and high specific speed high capacity
Ns = N Q1/2
H3/4
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30. Specific speed of different types of pumps
• Above 11,000 - Excellent design
• 7000 – 9000 - Average design
• Below 7000 - Poor design
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32. Process Pumps
A single stage pedestal mounted units with single
suction over hung impellers and with a single
packing box.
Designed for ease in dismantling and accessibility
with mechanical seals or packing arrangements.
To handle corrosive or otherwise difficult to
handle liquids.
ANSI B 73.1 – horizontal pumps
ANSI B 73.2 – Vertical inline pumps.
Horizontal pump upto 900 m3/hr and vertical
pumps upto 320 m3/hr
Both with heads upto 120 m.
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33. Interchangeability with respect to mounting, size
and location of suction and discharge nozzles,
input shaft, base plate and foundation bolts.
Horizontal process pump to (ANSI) Standard B73.1
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34. Vertical in-line process pump to ANSI Standard B73.2
Seals
Packing boxes for both packing and mechanical
seals
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35. Liquid at the seals surfaces must be free of
solids
Hence secondary compatible liquid to flush seal
or packing
Continuous escape of liquid past seal should be
minimum
To carry away the frictional heat developed.
Quench glands or catch pans for toxic or
corrosive liquid
Packing can be adjusted while the pump in
operation
Leaking mechanical seal requires pump shut
down
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36. Close coupled Pumps
Equipped with built in motor or turbine
Compact and suitable for a variety of services
Capacity upto 450 m3/hr for heads upto 73 m
Two stage units for heads upto 150 m.
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37. Canned motor pump
Close coupled unit with cavity housing the
motor rotor and the pump casing inter
connected
Motor bearing run by process liquids and all
seals are eliminated
Single stage pumps available upto 160 m3/hr
and heads upto 76 m.
Two stage units upto 183 m head.
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39. Vertical Pumps
Pump with vertical shaft having length from
drive end to impeller 1 m to 20 m or more
Either wet pumps (immersed) or dry pit pumps
(externally mounted)
Liquid level is above the impeller thus self
priming
Shaft seal is above liquid level and is not wetted
by the pumped liquid, simplifying sealing task.
Only choice when no bottom connection
permitted on the tank
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40. Disadvantages
Intermediate or line bearing required
Bearing must be lubricated when the shaft is
rotating
Corrosion resistant wetted parts results in
costly material for shaft, column etc.
Pumps are large and difficult to handle.
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42. Sump Pumps
Small single stage vertical pumps to drain
shallow pits or sumps
Similar to vertical pumps
Propeller and Turbine Pumps
Axial flow ( propeller) Pump
Very high capacity low head pumps
Flow excess of 450 m3/hr with heads 15 m or
less.
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44. Mixed flow pumps (part axial and part
centrifugal)
From 20 m3/hr and above and heads upto 30m
Usually vertical
Turbine Pump
Regenerative Pump
Employs a combination of mechanical impulse
and centrifugal force
Volume less than 20 m3/hr and high heads
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48. Maximum head available is determined by the
power available in the drive and the strength of
the pump parts
Automatic relief valve set to open at a safe
pressure higher than the normal or maximum
discharge pressure
Overall efficiency higher than centrifugal ones.
Flexibility of handling a wide range of capacity is
limited
May be either reciprocating or rotary
A cavity or cavities are alternately filled and
emptied by the action of pump.
Positive Displacement Pump
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49. Three classes- Piston pumps, Plunger pumps,
Diaphragm pumps
Equipped with valves for the inlet and discharge
of the liquid (operated by pressure difference)
Overall efficiency varies from 50% for small
pumps to 90% for large sizes.
Single cylinder or multi cylinder design
Single acting or double acting i.e.; pumping may
be accomplished from one or both ends of
piston.
Reciprocating Pump
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51. Simplex Double acting pumps
Direct acting or power drive
Duplex double acting pumps
Two cylinders where operation is coordinated
May be direct acting, steam drive or power drive
Piston Pump
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53. One or more constant diameter plungers
reciprocating through packing glands and
displacing liquid from cylinders in which there is
considerable clearance
Available with multi cylinders
Simplex and duplex cylinders are available with
horizontal design
With three or more cylinders are available with
vertical design
Plunger Pump
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55. Metering or proportioning Pump
Simplex plunger pumps mounted simply or in
gang with a common drive
Variable speed drive or stroke adjusting
mechanism provided to vary flow rate
Designed for ± 2% devices in capacities
Flow upto 11.35 m3/hr and head upto 68.9
MPa
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56. Diaphragm Pumps
Reciprocating driving member is a flexible
diaphragm fabricated of metal rubber or plastic
Elimination of packing and seals
Asset to handle hazardous and toxic liquids
Pneumatically actuated diaphragm pumps
• Requires no power source other than plant
compressed air
• Because of low speed and large valves, suitable
for gentle handling of liquid
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58. Rotary Pumps
Liquid is displaced by rotation of one or more
members within a stationary housing
Capacity decreases somewhat with increasing
pump differential pressure
Not truly positive displacement pumps
Material of construction must be corrosion
resistant, compatible when one part is running
against each other and capable of some
abrasive resistance
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60. Gear Pumps
When two or more impellers are used in a
rotary pump casing, the impellers will take the
form of toothed gear wheel- helical gears or of
lobed cam
Impellers rotate with externally small clearance
between them and between the surfaces of the
impellers and the casing
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62. In the fig. the two toothed impellers rotate as
indicated by arrows, the suction connection is at
the bottom.
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63. The pumped liquid flows into the spaces
between the impeller teeth as these cavities
pass the suction opening . The liquid then
carried around the casing to the discharge
opening, where it is forced out of the impeller
teeth mesh.
Classes of Rotary Pumps
• Internal or bearing type and external or bearing
type
• For handling liquid of lubricating type – interior
• Exterior bearing is oil lubricated
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65. Figure illustrates two rotor version in which the
liquid is fed to either the centre or the ends
depending upon the direction of rotation and
progresses axially in the cavities formed by the
meshing of threads or teeth. In three rotor
version centre rotor is the driving member
while the other two are driven good for viscous
liquids.
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68. Electromagnetic Pumps
Utilizes motor principle - a conductor in a
magnetic field, carrying a current which flows at
right angles to the direction of the field has a
force exerted on it.
Fluid is the conductor
The field and current can be produced in a
number of ways
Both AC and DC units are available
DC pumps are simpler but high current
requirement is limitation
AC pumps can obtain high current by using
transformers
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69. Vibration
Causes
Cavitation, impeller unbalance, loose bearings,
pipe pulsation
Frequency of vibration coincides with that of
the natural frequency of the pump system
When natural frequency is close to the upper
end of the operating speed range, then the
pump system should be stiffened
When the natural frequency is close to the
lower end of the operating range the unit
should be made more flexible
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70. Pump vibration level should fall within the
prescribed units. The reference level is specified
by the manufacturer
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71. Cavitation type problem
Velocity of the liquid is
too high as it approaches
the impeller eye.
Pump is operating at a
low-flow-producing
suction recirculation in
the impeller eye. This
results in a cavitation like
sound.
Plugged suction screen.
Piping gaskets with
undersized IDs installed,
a very common problem
in small pumps.
Install larger suction piping
or reduce flow through
pump.
Install bypass piping back to
suction vessel to increase
flow through pump.
Remember bypass flow may
have to be as high as 50
percent of design flow.
Check for indications of the
presence of screen. Remove
and clean screen.
Install proper-sized gaskets.
Possible causes Corrective action
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72. Column tray parts or
ceramic packing lodged
in the impeller eye.
Deteriorated impeller
eye due to corrosion.
Flow rate is high enough
above design that NPSH
for flow rate has
increased above NPSH.
Lined pipe collapsed at
gasket area or ID due to
build-up of corrosion
products between liner
and carbon-steel pipe.
Remove suction piping
and debris.
Replace impeller and
overhaul pump.
Reduce flow rate to that
of design.
Replace deteriorated
piping.
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73. Poor suction piping
layout, too many elbows
in too many planes, a tee
branch almost directly
feeding the suction of the
other pump, or not
enough straight run
before the suction flange
of the pump.
Vertical pumps
experience a vortex
formation due to loss of
submergence required by
the pump. Observe the
suction surface while the
pump is in operation, if
possible.
Redesign piping layout,
using fewer elbows and
laterals for tees, and
have five or more
straight pipe diameters
before suction flange.
Review causes of
vortexing. Consider
installation of a vortex
breaker such as a bell
mouth umbrella or
changes to sump design.
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74. Spare pump begins to
cavitate when attempt is
made to switch it with the
running pump. The spare is
“backed off” by the running
pump because its shutoff
head is less than the head
produced by the running
pump. This is a frequent
problem when one pump is
turbine-driven and one is
motor-driven.
Suction piping configuration
causes adverse fluid
rotation when approaching
impeller.
Throttle discharge of
running pump until
spare can get in system.
Slow down running
pump if it is a turbine or
variable-speed motor.
Install sufficient straight
run of suction piping, or
install vanes in piping to
break up prerotation.
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75. Check the discharge
block valve opening first.
It may be partially closed
and thus the problem.
Wear-ring clearances are
excessive (closed
impeller design).
Impeller-to-case or head
clearances are excessive
(open impeller design).
Air leaks into the system
if the pump suction is
below atmospheric
pressure.
Open block valve
completely.
Overhaul pump. Renew
wear rings if clearance is
about twice design value
for energy and
performance reasons.
Reposition impeller to
obtain correct clearance.
Take actions as needed
to eliminate air leaks.
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76. Increase in piping friction
to the discharge vessel
due to the following:
Gate has fallen off the
discharge valve stem.
Spring is broken in the
spring-type check valve.
Check valve flapper pin
is worn, and flapper will
not swing open.
Lined pipe collapsing.
Control valve stroke
improperly set, causing
too much pressure
drop.
Take the following
actions:
Repair or replace gate
valve.
Repair valve by
replacing spring.
Overhaul check valve;
restore proper
clearance to pin and
flapper bore.
Replace damaged pipe.
Adjust control valve
stroke as necessary.
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77. Suction and/or discharge
vessel levels are not
correct, a problem mostly
seen in lower-speed
pumps.
Calibrate level
controllers as necessary.
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78. Capacity type problem
Motor running backward
or impeller of double
suction design is
mounted backward.
Discharge pressure
developed in both cases
is about one-half design
value.
Entrained gas from the
process lowering NPSH
available.
Polymer or scale buildup
in discharge nozzle
areas.
Check for proper
rotation and mounting
of impeller. Reverse
motor leads if
necessary.
Reduce entrained gas in
liquid by process
changes as needed.
Shut down pump and
remove scale or
deposits.
Possible causes Corrective action
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79. Mechanical seal in suction
system under vacuum is
leaking air into system,
causing pump curve to
drop.
The pump may have
formed a vortex at high
flow rates or low liquid
level. Does the vessel
have a vortex breaker ?
Does the incoming flow
cause the surface to swirl
or be agitated ?
Variable-speed motor
running too slowly.
Change percentage
balance of seal faces or
increase spring tension.
Reduce flow to design
rates. Raise liquid level
in suction vessel. Install
vortex breaker in
suction vessel.
Adjust motor speed as
needed.
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80. Bypassing is occurring
between volute channels
in a double-volute pump
casing due to a casting
defect or extreme
erosion.
The positions of impellers
are not centered with
diffuser vanes. Several
impellers will cause
vibration and lower head
output.
When the suction system
is under vacuum, the
spare pump has difficulty
getting into system.
Overhaul pump; repair
eroded area.
Overhaul pump;
reposition individual
impellers as needed.
Reposition whole rotor
by changing thrust
collar locator spacer.
Install a positive-
pressure steam (from
running pump) to fill
the suction line from
the block valve through
the check valve.
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81. Certain pump designs use an
internal bypass orifice port
to alter head-flow curve.
High liquid velocities often
erode the orifice, causing the
pump to go farther out on
the pump curve. The system
head curve increase corrects
the flow back up the curve.
Replacement impeller is not
correct casting pattern;
therefore NPSH required is
different.
Volute and cutwater area of
casing is severely eroded.
Overhaul pump,
restore orifice to
correct size.
Overhaul pump,
replace impeller with
correct pattern.
Overhaul pump;
replace casing or
repair by welding.
Stress-relieve after
welding as needed.
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82. Motor overload problem
Polymer buildup
between wear surfaces
(rings or vanes).
Excessive wear ring
(closed impeller) or
cover-case clearance
(open impeller).
Pump circulating
excessive liquid back to
suction through a
breakdown bushing or a
diffuser gasket area.
Remove buildup to
restore clearances.
Replace wear rings or
adjust axial clearance of
open impeller. In severe
cases, cover or case
must be replaced.
Overhaul pump,
replacing parts as
needed.
Possible causes Corrective action
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83. Minimum-flow loop left
open at normal rates, or
bypass around control
valve is open.
Discharge piping leaking
under liquid level in
sump-type design.
Electrical switch gear
problems cause one
phase to have low
amperage.
Specific gravity is higher
than design
specification.
Close minimum-flow loop
or control valve bypass
valve.
Inspect piping for leakage.
Replace as needed.
Check out switch gear and
repair as necessary.
Change process to adjust
specific gravity to design
value, or throttle pump to
reduce horsepower
requirements. This will not
correct problem with some
vertical turbine pumps that
have a flat horsepower-
required curve.
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84. Pump motor not sized
for end of curve
operation.
Open impeller has slight
rub on casing. Most
often occurs in
operations from 250 to
400°F due to piping
strain and differential
growth in the pump.
A replacement impeller
was not trimmed to the
correct diameter.
Replace motor with one
of larger size, or reduce
flow rate.
Increase clearance of
impeller to casing.
Remove impeller from
pump and turn to
correct diameter.
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85. Pump specification
Factors
1. Application, Scope, type
2. Service condition
3. Operating condition
4. Special considerations
Casing connection
Impeller details
Shaft
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86. Shifting box details
Lubricate , sealing etc.
Bearing frame and bearing
Base plate & coupling
Materials
Special operating condition and
miscellaneous item
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