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Dr. Medhat Khalil
Aug 17, 2021
In General Discussions
Chapter 1: Introduction to Hydraulic Fluids and contamination Control
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Dr. Medhat Khalil
Aug 17, 2021
In General Discussions
Chapter 1: Introduction to Hydraulic Fluids and contamination Control
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Dr. Medhat Khalil
Aug 12, 2021
In General Discussions
Hands-On Training content media
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Dr. Medhat Khalil
Jul 22, 2020
In General Discussions
Please send me your feedback about the contents of this textbook https://www.compudraulic.com/product-page/hydraulic-systems-volume-7-modeling-and-simulation-for-application-engineers
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Dr. Medhat Khalil
Mar 15, 2020
In Fluid Power Quizzes
The system shown below represents? A. A Closed-loop control system using a stroke-controlled proportional valve. B. A Closed-loop control system using a force-controlled proportional valve. C. An open-loop control system using a force-controlled proportional valve. D. An open-loop control system using a stroke-controlled proportional valve
Fluid Power Quiz #2 content media
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Dr. Medhat Khalil
Nov 24, 2019
Jet Pipe versus Flapper-Nozzle Servo Valve content media
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Dr. Medhat Khalil
Oct 25, 2019
In General Discussions
Hydraulic Fluids content media
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Dr. Medhat Khalil
Aug 29, 2019
In General Discussions
Hi group members, I'm wondering where are you? Please feel free to share your stories and experience in fluid power. Learning process never stops
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Dr. Medhat Khalil
Aug 22, 2019
In General Discussions
Electro hydraulic Seminar. Well attended by a great group of industry professional
This week’s seminar content media
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Dr. Medhat Khalil
Aug 19, 2019
In General Discussions
I am working now to develop the workbook for volume 3 - when it is completed, I will start on writing volume 4 (Hydraulic Fluid Conditioning) - this will contain chapters - Hydraulic System Safety - Hydraulic Transmission Lines - Hydraulic Reservoirs - Hydraulic Sealing Ekements - Hydraulic Heat Exchangers
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Dr. Medhat Khalil
Jul 30, 2019
In General Discussions
As shown in the figure, based on the hardware configuration, control electronics are classified as follows: Panel Mounted Control electronics: Panel Mounted ECUs are referred to as Control Cards. They are kept apart from the valve in a conditioned and guarded cabinet. The front panel, as shown in the figure, gives access to the end user to tune the functions contained in the ECU. Modular Control Electronics: Modular ECUs are contained inside a customized enclosure. It can be used for industrial/mobile applications. It can be used to control a single valve or a multi-axis system. Integrated Control Electronics: Integrated Control Electronics are referred to as Onboard Electronics (OBE). Using this configuration results in a compact system, reduced wiring effort, and ease of network interfacing. There are performance limitations at high temperature (good for T < 60 OC).
Control Electronics for Proportional and Servo Valves content media
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Dr. Medhat Khalil
Jul 23, 2019
In Fluid Power Quizzes
1. Hydraulic valves are classified into which of the following 3 basic functions? A. Pressure control, directional control and flow control. B. Pressure control, directional control and speed control. C. Force control, directional control and flow control. D. Pressure control, torque control and flow control.
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Dr. Medhat Khalil
Jul 09, 2019
In General Discussions
Sorry for not getting back to you - still relaxing on the North Cost of Egypt
Still in Vacation content media
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Dr. Medhat Khalil
Jun 05, 2019
In General Discussions
As a matter of fact, hydraulic systems are known as systems of higher power density and less energy density as compared to the electrical systems. In order to get better understanding of these terms, look at Fig. 1.10. The figure shows, on the upper part of it, a comparison between a hydraulic motor and an electric motor that has the same power capacity. The electric motor has ten times the weight and size of the hydraulic motor. This means that the hydraulic motor has a higher power/weight ratio. Power/Weight Ratio is also referred as Specific Power or Power Density. This property is very important for mobile machines since it affects directly the compactness of the machine. The higher the value of the power density the more compact the machine. That justifies the wide use of hydraulic systems for earth moving machines and the aerospace industry. To understand this property from another angle let us compare hydraulic motors and electric motors of the same size as shown in the lower part of Fig. 1.10. The figure shows that a hydraulic motor receiving pressurized fluid with pressure of 300 psi, can produce the same amount of power as an electric motor of the same size. The average working fluid pressure in commercial hydraulic systems is 3000 psi. This means that a hydraulic motor can have ten times the power capacity of an electric motor of the same size. The term Energy Density refers to the ability to store energy. Energy can be stored in a hydraulic system by storing a volume of fluid under pressure of a gas in an element called accumulator. The value of the energy that can be stored in an accumulator is limited by the volume of the accumulator and the maximum pressure of the compressed gas in the accumulator. So, energy that can be stored in accumulators is limited in value as compared to the value of energy that can be stored in electrical systems in batteries.
Power Density vs. Energy Density in Fluid Power content media
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Dr. Medhat Khalil
Jun 04, 2019
In General Discussions
Chapter 1 - Lesson 5C
Sample Lesson from OITA content media
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Dr. Medhat Khalil
Jun 04, 2019
In General Discussions
Join Online Industrial Training Academy (OITA) and enjoy watch free Fluid Power Courses https://compudraulic-oita.newzenler.com
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Dr. Medhat Khalil
Jun 03, 2019
In General Discussions
Share your fluid power experience, memories, concerns, and even war stories! Let me start with this news: I'm excited about the upcoming the worldwide-largest construction expo in Vegas, March 2020. I will teach the first four hours along the conference (Fundamentals of Fluid Power) See us in Booth SL-80036 https://www.conexpoconagg.com/
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Dr. Medhat Khalil
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