Hydraulic Systems Volume 2 Electro-Hydraulic Components .
Hydraulic Systems Volume 2Electro-Hydraulic Componentsand SystemsDr. Medhat Kamel Bahr Khalil, Ph.D, CFPHS, CFPAI.Director of Professional Education and Research Development,Applied Technology Center, Milwaukee School of Engineering,Milwaukee, WI, USA.CompuDraulic LLCwww.CompuDraulic.com
CompuDraulic LLCHydraulic System Volume 2Electro-Hydraulic Components and SystemsISBN: 978-0-9977634-2-3Printed in the United States of AmericaFirst Published by 2017Revised by January 2019All rights reserved for CompuDraulic LLC.3850 Scenic Way, Franksville, WI, 53126 USA.www.compudraulic.comNo part of this book may be reproduced or utilized in any form or by any means, electronic orphysical, including photocopying and microfilming, without written permission fromCompuDraulic LLC at the address above.DisclaimerIt is always advisable to review the relevant standards and the recommendations from thesystem manufacturer. However, the content of this book provides guidelines based on theauthor's experience.Any portion of information presented in this book could be not applicable for someapplications due to various reasons. Since errors can occur in circuits, tables, and text, theauthor/publisher assumes no liability for the safe and/or satisfactory operation of any systemdesigned based on the information in this book.The author/publisher does not endorse or recommend any brand name product by includingsuch brand name products in this book. Conversely the author/publisher does not disapproveany brand name product by not including such brand name in this book. The publisherobtained data from catalogs, literatures, and material from hydraulic components and systemsmanufacturers based on their permissions. The author/publisher welcomes additional datafrom other sources for future editions. This disclaimer is applicable for the workbook (iffound). associated with this textbook
1Hydraulic Systems Volume 2: Electro-Hydraulic Components and SystemsTable of ContentsHydraulic Systems Volume 2Electro-Hydraulic Components and SystemsPREFACE, 10ACKNOWLEDGEMENT, 11ABOUT THE BOOK, 12ABOUT THE AUTHOR, 15Chapter 1: Hydraulic versus Electrical Systems, 161.1- Structural Analogy between Hydraulic and Electrical Systems, 171.1.1- Power Generation (Conversion), 181.1.1.1- Electrical Power Generators, 181.1.1.2- Hydraulic Power Generators, 191.1.2- Power Control, 201.1.2.1- Power Quantification, 201.1.2.2- Effort Variable Controllers (Overload Protection), 211.1.2.3- Flow Variable Controllers (Resistive Elements), 221.1.2.4- Directional Controllers, 281.1.2.5- Energy Storage Elements (Capacitive Elements), 291.1.2.6- Non-Return Elements, 301.1.2.7- Electrical versus Hydraulic Power Control Elements, 301.1.3- Power Consumption (Actuation), 311.1.3.1- Rotational Actuators, 311.1.3.2- Linear Actuators, 331.2- Operational Analogy between Hydraulic and Electrical Systems, 341.2.1- Energy Transmission in a Circuit, 341.2.2- Energy Transmission Efficiency, 351.2.3- Energy Transmission Cost Factor, 361.2.4- Energy Transmission Distance, 371.2.5- Readiness of Operation, 381.2.6- Cleanliness of Operation, 391.2.7- Maintenance of Operation, 401.2.8- Safety of Operation under High Temperature, 411.2.9- Noise of Operation, 42
2Hydraulic Systems Volume 2: Electro-Hydraulic Components and SystemsTable of ContentsChapter 2: Hydro-Mechanical versus Electro-Hydraulic Solutions, 432.1- Features and Challenges of Electro-Hydraulic Systems, 442.2- Pressure Control Solutions, 462.2.1- Pressure Control using Hydro-Mechanical Pressure Relief Valve, 462.2.2- Pressure Control using Hydro-Mechanical Pressure Compensated Pump, 472.2.3- Multiple Pressure Settings using Electro-Hydraulic Switching Valves, 482.2.4- Pressure Control using an Electro-Hydraulic Continuous Valve, 502.2.5- Pressure Control using an Electro-Hydraulic Pressure Compensated Pump, 522.3- Flow Control Solutions, 542.3.1- Flow Control using Hydro-Mechanical Flow Control Valve, 542.3.2- Flow Control using Hydro-Mechanical Displacement Controlled Pump, 552.3.3- Multiple Flow Settings using Electro-Hydraulic Switching Valves, 562.3.4- Flow Control using an Electro-Hydraulic Continuous Valve, 582.3.5- Flow Control using an Electro-Hydraulic Displacement Controlled Pump, 602.3.6- Flow Control using a Fixed Pump Driven by Variable Speed Motor, 622.4- Power Control Solutions, 642.4.1- Hydro-Mechanical Power Controlled Pumps, 652.4.2- Electro-Hydraulic Power Controlled Pumps, 672.5- Sequence Control Solutions, 702.5.1- Hydro-Mechanical Sequence Control, 702.5.2- Electro-Hydraulic Sequence Control, 712.6- Hydraulic Deceleration System, 732.61- Hydro-Mechanical Deceleration System, 732.6.2- Electro-Hydraulic Deceleration System, 742.7- Cylinder Speed Synchronization, 752.7.1- Hydro-Mechanical Cylinder Speed Synchronization, 752.7.2- Electro-Hydraulic Cylinder Speed Synchronization, 762.8- Accumulator Charging, 772.8.1- Hydro-Mechanical Accumulator Charging, 772.8.2- Electro-Hydraulic Accumulator Charging, 782.9- Control of Overrunning Loads, 802.9.1- Hydro-Mechanical Overrunning Load Control, 802.9.2- Electro-Hydraulic Overrunning Load Control, 81
3Hydraulic Systems Volume 2: Electro-Hydraulic Components and SystemsTable of Contents2.10- Control Block Actuation in Mobile Applications, 822.10.1- Hydro-Mechanical Control Block Actuation, 822.10.2- Electro-Hydraulic Control Block Actuation, 83Chapter 3: Switching Valves Construction and Operation, 843.1- Basic Electro-Magnetic Concepts, 853.1.1- Magnetic Field around a Conducting Wire, 853.1.2- Magnetic Field Measuring Units, 853.1.3- Magnetic Field Intensity, 863.1.4- Magnetic Field around a Coil, 873.1.5- Electro-Magnetic Force, 883.2- Switching Solenoids, 893.2.1- Switching Solenoid Basic Structure, Operation, and Functions, 893.2.2- Wiring Methods of a Coil, 923.2.3- Switching Solenoids Force-Stroke Relationship, 953.2.4- Switching Solenoid Performance Terminologies, 973.3- Switching Solenoids for Electro-Hydraulic Valves, 993.3.1- Dry (Air) Type Switching Solenoids for EH Valves, 993.3.2- Wet (Oil) Type Switching Solenoids for EH Valves, 1013.3.3- Dry versus Wet Type Switching Solenoids for EH Valves, 1023.3.4- DC Switching Solenoids for EH Valves, 1033.3.4.1- Construction and Operation of DC Switching Solenoids for EH Valves, 1033.3.4.2- Performance of DC Switching Solenoids for EH Valves, 1043.3.4.3- Applications of DC Switching solenoids for EH Valves, 1053.3.5- AC Switching Solenoids for EH Valves, 1063.3.5.1- Construction and Operation of AC Switching Solenoids for EH Valves, 1063.3.5.2- AC Hum, 1073.3.5.3- Eddy Current, 1093.3.5.4- Inrush Current, 1103.3.5.5- Performance of AC Switching Solenoids for EH Valves, 1133.3.5.6- Applications of AC switching Solenoids for EH Valves, 1143.3.6- DC versus AC Switching Solenoid, 1143.3.7- Electrical Ratings for Switching Solenoids, 1153.3.8- Manual Override, 1163.3.9- Switching Solenoids for Cartridge Valves, 1173.3.10- Standard Electrical Terminations for Switching Solenoids, 1183.4- Electro-Hydraulic Switching Directional Control Valves, 1203.5- Electro-Hydraulic Switching Pressure Control Valves, 131
4Hydraulic Systems Volume 2: Electro-Hydraulic Components and SystemsTable of Contents3.6- Electro-Hydraulic Switching Flow Control Valves, 133Chapter 4: Electrical Circuits for Switching Valves, 1344.1- Best Practices for Safe Operation of Electro-Hydraulic Systems, 1354.2- Basic Electrical Symbols, 1404.3- Basic Electrical Devices, 1424.3.1- Measuring Instruments, 1424.3.2- Electrical Pushbuttons and Switches, 1444.3.3- Limit Switches, 1454.3.4- Proximity Switches, 1464.3.5- Pressure Switches, 1474.3.6- Fluid Flow Switches, 1484.3.7- Fluid Level Switches, 1484.3.8- Temperature Switches, 1494.3.9- Control Relays, 1494.3.10 - Programmable Logic Controllers (PLCs), 1514.4- Electrical Schematic Diagrams, 1534.4.1- JIC Schematic Diagrams, 1534.4.2- Wiring Diagrams, 1564.4.3- Sequence Diagrams, 1574.5- Electrical Circuits for Applications of Switching Valves, 1584.5.1- Identity (YES Function) by Direct Activation, 1584.5.2- Negation (NOT Function) by Direct Activation, 159,4.5.3- Identity (YES Function) by Indirect Activation, 1604.5.4- Negation (NOT Function) by Indirect Activation, 1614.5.5- Signal Storage by Electrical Latching, 1624.5.6- Electromechanical Protection of a Valve with Two Solenoids, 1634.5.7- Electrical Protection of a Valve with Two Solenoids, 1644.5.8- Position-Dependent Cylinder Deceleration, 1674.5.9- One-Cycle Hydraulic Cylinder Reciprocation, 1714.5.10- Continuous Cylinder Reciprocation, 1734.5.11- Panic Circuit, 1764.5.12- Conjunction Functions, 1774.5.13- Disjunction Functions, 1814.5.14- Timer Circuits, 1834.5.15- Sequence Control, 185
5Hydraulic Systems Volume 2: Electro-Hydraulic Components and SystemsTable of ContentsChapter 5: Proportional Valves, 1915.1- Introduction to Proportional Valves, 1925.2- Proportional Solenoids, 1965.2.1- Force-Controlled Proportional Solenoid, 1965.2.2- Stroke-Controlled Proportional Solenoid, 2005.3- Proportional Directional Control Valves, 2045.3.1- Interpretation of Symbols for Proportional Directional Valves, 2045.3.2- Hydraulic Static Characteristics of Proportional Directional Valves, 2055.3.3- Direct-Operated Force-Controlled Proportional Directional Valve, 2075.3.4- Direct-Operated Stroke-Controlled Proportional Directional Valve, 2105.3.5- High Performance Proportional Directional Valve, 2135.3.6- Pilot-Operated Force-Controlled Proportional Directional Valve, 2185.3.7- Pilot-Operated Stroke-Controlled Proportional Directional Valve, 2255.3.8- Proportional Directional Valves with Variable Load Compensator, 2325.4- Proportional Pressure Control Valves, 2365.4.2- Hydraulic Static Characteristics of Proportional Pressure Relief Valves, 2375.4.3- Direct-Operated Force-Controlled Proportional Pressure Relief Valves, 2385.4.4- Direct-Operated Stroke-Controlled Proportional Pressure Relief Valves, 2425.4.5- Pilot-Operated Force-Controlled Proportional Pressure Relief Valves, 2445.4.6- Pilot-Operated Stroke-Controlled Proportional Pressure Relief Valves, 2515.4.7- Proportional Pressure Reducing Valves, 2525.5- Proportional Flow Control Valves, 2545.6- Proportional Valves for Mobile Applications, 259Chapter 6: Servo Valves, 2606.1- Introduction to Servo Hydraulics, 2616.1.1- Historical Background, 2616.1.2- Servo Valve Applications, 2616.2- Torque Motors, 2646.2.1- Torque Motor Construction and Operation, 2646.2.2- Torque Motor Wiring, 2666.2.2.1- Parallel Wiring, 2666.2.2.2- Series Wiring, 2676.2.2.3- Single Wiring, 268
6Hydraulic Systems Volume 2: Electro-Hydraulic Components and SystemsTable of Contents6.3- Servo Valve Configurations, 2696.3.1- Power Assistance using Mechanical Servo Valve, 2696.3.2- Single-Stage Servo Valve, 2716.3.3- Two-Stage Servo Valve with Tracking Sleeve, 2736.3.4- Flapper–Nozzle Concept of Operation, 2756.3.4.1- Half-Bridge Flapper-Nozzle Concept, 2756.3.4.2- Full-Bridge Flapper-Nozzle Concept, 2776.3.4.3- Power Gain of Servo Valve, 2796.3.5- Two-Stage Flapper–Nozzle Servo Valve with Barometric Feedback, 2806.3.6- Two-Stage Flapper–Nozzle Servo Valve with Mechanical Feedback, 2826.3.7- Two-Stage Flapper–Nozzle Servo Valve with Electrical Feedback, 2926.3.8- Two-Stage Flapper–Nozzle Servo Valve with Mechanical and Electrical Feedback, 2946.3.9- Three-Stage Flapper–Nozzle Servo Valve, 2956.3.10- Jet Pipe Concept of Operation, 2996.3.11- Two-Stage Jet Pipe Servo Valve with Mechanical Feedback, 3006.3.12- Two-Stage Jet-Pipe Servo Valve with Electrical Feedback, 3046.3.13- Jet Pipe versus Flapper-Nozzle Pilot Stage, 2066.3.14- Two-Stage Jet-Deflector Servo Valve with Mechanical Feedback, 307Chapter 7: Electro-Hydraulic Valve Selection Criteria, 3097.1- Importance of Proper Selection of an EH Valve, 3107.2- Electro-Hydraulic Valve Selection Criteria, 3117.3- Valve Type, 3127.4- Valve Spool Design, 3167.4.1- Spool Null Conditions, 3167.4.1.1-Overlapped (Closed-Center) Null Conditions, 3177.4.1.2- Zero-Lapped (Critical-Center) Null Conditions, 3197.4.1.3- Underlapped (Open-Center) Null Conditions, 3207.4.2- Spool Transitional Conditions, 3237.4.3- Spool Fail-Safe Position, 3247.4.4- Spool Control Edges, 3257.4.4.1- Holes versus Control Edges, 3257.4.4.2- Custom Control Edges, 3267.4.4.3- Standard Control Edges, 3267.4.4.4- Distribution of Control Edges, 3327.5- Valve Static Characteristics, 3347.5.1-Valve Flow Gain, 3357.5.2- Valve Flow-Pressure Coefficient, 3457.5.3-Power Limits, 3507.5.4-Pressure Gain, 353
7Hydraulic Systems Volume 2: Electro-Hydraulic Components and SystemsTable of Contents7.5.5-Valve Sizing, 3557.5.6-Valve Hysteresis, 3677.6-Valve Dynamic Characteristics, 3707.6.1-Step Response, 3707.6.2-Frequency Response, 3767.7-Valve Operating Conditions, 3837.8-Examples of Published Data, 383Chapter 8: Open-Loop versus Closed-Loop EH Applications, 3928.1- Electro-Hydraulic Open-Loop Control Systems, 3938.1.1- Structure of Electro-Hydraulic Open-Loop Control Systems, 3938.1.2- Features of Electro-Hydraulic Open-Loop Control Systems, 3948.1.3- Electro-Hydraulic Open-Loop Speed Control Systems, 3958.1.4- Electro-Hydraulic Open-Loop Load Control Systems, 3978.2- Electro-Hydraulic Closed-Loop Control Systems, 4008.2.1- Structure of Electro-Hydraulic Closed-Loop Control Systems, 4008.2.2- Features of Electro-Hydraulic Closed-Loop Control Systems, 4018.2.3- Electro-Hydraulic Closed-Loop Speed Control Systems, 4038.2.3.1- Electro-Hydraulic Closed-Loop Flow Control System, 4038.2.3.2- Electro-Hydraulic Closed-Loop Motor Speed Control System, 4068.2.4- Electro-Hydraulic Closed-Loop Load Control Systems, 4088.2.4.1- EH Closed-Loop Single-Acting Cylinder Pressure Control System, 4088.2.4.2- Electro-Hydraulic Closed-Loop Single-Acting Cylinder Force Control System, 4118.2.4.3- EH Closed-Loop Double-Acting Cylinder Pressure Control System, 4128.2.4.4- EH Closed-Loop Double-Acting Cylinder Force Control System, 4158.2.5- Electro-Hydraulic Closed-Loop Position Control Systems, 4168.3- Closed-Loop Performance Analysis, 4208.4- Electro-Hydraulic Control Systems Applications Examples, 4228.4.1- Industrial Applications, 4228.4.2- Mobile Applications, 430Chapter 9: Control Electronics for Electro-Hydraulic Valves, 4379.1- Control Electronics Basic Functions, 4389.2- DC Power Supply, 441
8Hydraulic Systems Volume 2: Electro-Hydraulic Components and SystemsTable of Contents9.3- Signal Amplifier, 4429.4- Dither Signal, 4439.5- Pulse Width Modulation, 4439.6- Input Signal Generator, 4479.6.1- Format of Input Signal, 4479.6.2- Source and Mode of Input Signal, 4489.7- Feedback Sensors, 4509.8- PID Controller, 4509.9- Gain Adjustor, 4539.10- Ramp Adjustor, 4569.11- Null Adjustor (IBias), 4599.12- Dead Band Eliminator (Imin), 4629.13- Saturation Adjustor (Imax), 4659.14- Control Electronics Basic Configurations, 4679.15- Hardware Configuration, 4689.16- Typical Electronic Schematics for Continuous Valves, 469Chapter 10: Electro-Hydraulic Valves Commissioning and Maintenance, 50410.1- Installation and Commissioning Instructions, 50510.1.1- Cleanliness, 50510.1.2- Installation Position (review phrasing on the slide), 50610.1.3- Mounting Screws, 50610.1.4- Seals (rephrase on the slide), 50610.1.5- Electrical Connections, 50610.1.6- Storage Locations, 50610.2- Filtration Requirements, 50710.2.1-Reservoir Breather Filter, 50710.2.2-Filtration, 50710.2.3- System Flushing, 51110.3- Electro-Hydraulic Valve Tests and Maintenance, 512
9Hydraulic Systems Volume 2: Electro-Hydraulic Components and SystemsTable of ContentsAPPENDIXES, 513APPENDIX A:LIST OF FIGURES, 513APPENDIX B:LIST OF TABLES, 531APPENDIX C:LIST OF ANIMATED CIRCUITS (AUTOMATION STUDIO), 531APPENDIX E:LIST OF REFERENCES, 533INDEX, 542
10Hydraulic Systems Volume 2: Electro-Hydraulic Components and SystemsPrefacePREFACEQuestions being asked that are: “should a machine built based on electrical or hydraulic powertransmission and control system?” and “what are the benefits of converting a legacy hydromechanical system into an electro-hydraulic system?”This book is intended for industry professionals who would like to achieve a deeper understandingof the principles of electro-hydraulic control, and who would like to improve their practical skills inbuilding an EH-driven machine. Unlike similar books, the contents of this book are presented in aunique way. It fills the gap between the very academic style of fluid power books and the verycommercial style of books that are produced by fluid power manufacturers basically to promote theirproducts.The book contains Animated Circuits Files to download. The files are produced by AutomationStudio to presents examples of electrical circuits that drive switching valves. Other circuits are topresent examples of open-loop and closed-loop electro-hydraulic control systems.Hydraulic system builders and users will find this book beneficial in understanding the constructionand the operating principles of the electro-hydraulic systems. The book is written to cover theknowledge of electro-hydraulic components including solenoid operated valves, proportional valves,servo valves and amplifiers. The book also covers the technicalities of in-field tuning of open-loopand closed-loop electro-hydraulic systems. The book also presents guideline to select a valve for anapplication and how to read data sheet of a valve. The book covers the basic functions contained inthe electronic control units that drive EH valves such as gain adjustor, maximum current limiter,ramp generator, pulse width modulation, dead band eliminator, null adjustment, and much more.With more than twenty-five years of experience in teaching fluid power for industry professionals,the author had effectively applied his solid understanding to the subject and his post-doctoral level ofacademic education in the preparation of this book. The book features in brief are easy language,brand non-biased, practical oriented, associated with a workbook, colored, and demonstrative.The author wants to continue on his goal of supporting fluid power and motion control professionaleducation by developing the following series of volumes:Hydraulic Systems Volume 1: Introduction to Hydraulics for Industry Professionals.Hydraulic Systems Volume 2: Electro-Hydraulic Components and Systems.Hydraulic Systems Volume 3: Hydraulic Fluids and Contamination Control.Hydraulic Systems Volume 4: Hydraulic Fluids Conditioning.Hydraulic Systems Volume 5: Best Practices for Safety and Maintenance.Hydraulic Systems Volume 6: Troubleshooting and Failure Analysis.Hydraulic Systems Volume 7: Hydraulic Systems Modeling and Simulation for Application Engineers.Hydraulic Systems Volume 8: Design Strategies of Hydraulic Systems.Hydraulic Systems Volume 9: Design Strategies of Electro-Hydraulic Systems.Hydraulic Systems Volume 10: Hydraulic Components Modeling and Simulation.
11Hydraulic Systems Volume 2: Electro-Hydraulic Components and SystemsAcknowledgmentACKNOWLEDGEMENTAll praise is to Allah who granted me the knowledge, resources and health to finish this work.To the soul of my parents who taught me the values of ISLAMTo my family: wife, sons, daughters in law, and grandson “Adam”To my best teachers and supervisorsTo friends who were always supportiveThe author wishes to thank these companies: (Bosch Rexroth, Assofluid, Atos, Wandfluh,Hydraforce, Moog, Parker, and others) who permit us to use some of their copyrighted material tomake this book more demonstrative.Lastly, the author particularly wishes to thank the following gentlemen for their effective reviewsof the book language: Tom Wanke, Director of Fluid Power Institute at Milwaukee School of Engineering. Kamara Sheku, Dean of Applied Researches at Milwaukee School of Engineering.
12Hydraulic Systems Volume 2: Electro-Hydraulic Components and SystemsAbout the BookABOUT THE BOOKBook Description:The book is a learning package for students and professiona
2.3.3- Multiple Flow Settings using Electro-Hydraulic Switching Valves, 56 2.3.4- Flow Control using an Electro-Hydraulic Continuous Valve, 58 2.3.5- Flow Control using an Electro-Hydraulic Displacement Controlled Pump, 60 2.3.6- Flow Control using a Fixed Pump Driven by
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processes are optimized for next generation manufacturing systems. In two previous papers we outlined the design of a heavyduty handling - system and its hydraulic lifting mechanism based on Industry 4.0 principles. Electro-hydraulic circuit modelling as well material selection for electro-hydraulic operation of the new designed system
Hydraulic Systems - Components and more Page 7 Contents Chapter 1: The hydraulic system 11 Hydraulic elements 12 Hydraulic fluid 13 Materials 14 Physical design 14 Chapter 2: The hydraulic cylinder 15 Classification of hydraulic cylinders 15 Type of effect 15 Working area 16 Series and working pressure 18 What's important? 21 Cylinder construction 25 Design 26
This enables the electro-hydrostatic actuator to efficiently use energy and deliver power on demand. Figure 2 compares traditional electro-mechanical, electro-hydraulic . modular design with a self-contained hydraulic system and its principle of using power on demand. In addition, it does not use
17 Hydraulic unit Hydraulic unit, v.v. electro motoren, 2,2 kW, 220/380 volt 50 18 RVS electrische trolley . Electro aandrijfmotor, "Flender" 20 23 Trommel electro motor Trommel electro motor, type SAF70VZ9, 1400 rpm, 3 kW, v.v.
TASC Reading Test Practice Items Read the text. Then answer the questions. Excerpt from Main Street by Sinclair Lewis Main Street is a novel about a girl who grew up in the big city. She has married a physician who moves them to the small town in the Midwest in which he grew up. She is reluctant to move from the city she knows, but goes along with her husband thinking that perhaps she can .
