Introduction to Proportional (Servo) Valves (Full Lecture)

In this lesson we'll take a brief introductory look at proportional (servo) valves. We'll discuss how proportional valves serve to control both flow rate and direction as well as examine proportional valve construction. We'll learn that proportional valves are electrically actuated continuously variable combinations of flow control valves and directional control valves integrated in the same package that lend themselves to advanced functionality. We'll examine proportional valve performance data, specifically, flow rate as a function of applied voltage and discuss dead band, hysteresis, overlapped, and line to line spools, and observed non-linearities. Additionally, we'll examine hysteresis compensation via closed loop control of spool position using the internally generated feedback provided by a spool position transducer know as an LVDT. Additionally, we'll briefly introduce acceleration and deceleration control made possible by ramp generators. Finally, we'll briefly discuss filtration and fluid requirements and maintenance and service procedures unique to proportional valves. (Full Lecture)
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For more FREE online technical training check out the following playlists available at the bigbadtech channel:
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Motor Control • Motor Control
Motors and Generators • Motors and Generators
Motor Drives/Variable Frequency Drives (VFD) • Motor Drives
Programmable Logic Controllers (PLCs) • Programmable Logic Con...

[@aobozhang116]

Can not believe how you manage to maintain such high level accuracy of each terminology in explaining everything in the video and make it so easy to understand for me. Thank you very much for the excellent work!

[@bigbadtech]

Don't give me too much credit. I just turn the mike on, click record, and make it up as I go along. Just kidding. Thanks for the kind words. Lots of work goes into this material and I'm glad you're make use of it.

[@AliTanoli-cq3js]

Best video explanation of Proportional valves on youtube. My man really understands the topics and explains it with great depth.

[@chuckmm5611]

This video is a huge help in understanding a topic that has been cloudy. It is clear this video lecture was well put together and involved a great amount of time and energy. Thank You for your commitment to the industry and education.

[@KuyaPow626]

Man you are an exceptional teacher, thank you so much for the clearly informative pace

[@someguy9431]

Your channel is out-fricking-standing!

[@stevenafful7377]

Big thanks for your easy-to-understand video honestly, it has been a great help..

[@Panzerabwehr]

Awesome video! Thank you very much for the good work and explanations!

[@jW-xz7sr]

Wow, so glad I found your channel. I can follow the way you teach and explain. I hope you have info on different PWM controllers and sub systems that discuss LVDT and motion sensors, or maybe even Oscope and troubleshooting. That would be awesome. Thank you. I have only watched this one Video. Guess I will see what else you have . Thanks a lot.

[@ankitsonu2511]

Sir, You are exceptional teacher, because of you I am able to do my job in a much smoother way. I didn't knew hydraulics but then I somehow discovered your channel on KZbin . Thanks for everything 🙏🙏

[@arslanahmad1195]

Thank you very much Sir for a very well put down lecture

[@johntrauger68]

Just what I needed.

[@roguefab]

Great job man. Really an excellent intro.

[@yehtutnaung7164]

Thank you very much for sharing informative lecture .

[@trpservices]

very nicely done I now understand thank you

[@kingcuan5261]

I work on press brakes and guilotines and other heavy sheet metal working machinery this video has been great

[@phanghinchiew2782]

thank you very much for sharing the lecture is very concise ,clear ,neasy to understand good''''

[@neatmachine]

Nicely done!

[@fevzitopcu9023]

thanks for the share

[@sumanpakhrin6802]

Hollah This an awesome lecture. Thanks for such a Lucid Explanation.

[@machineryoverhaulretrofitm6607]

thanks alot

[@eliohern9622]

Nice!

[@NK-li8py]

Superb

[@sirimanustunwutibundit5986]

Thank

[@alyyhyder9791]

Hello Jim, thank you for everything you have posted. Can you please cover secondary control systems as well in one of your videos? Btw im a huge fan and you have contributed a lot to my sucess!

[@shawnballee6053]

Good lecture covering all the basic points. some valves just have ramp, and don't differentiate between acceleration and deceleration. Could do a whole lecture on P, PI, and PID controls.

[@bigbadtech]

Ironically enough I use the proportional valve as the means of introducing PID controls. Very well suited for this topic. Unfortunately I'm devoting my effort towards AC Circuit Analysis this summer and I won't be able to get to this topic in the near future, however, I do have a sample lecture coming up about open loop control (using proportional valves) that at least prepares students for these topics. The "Acceleration Control Using Proportional Valves" lecture is a good example of open loop control, the repetitive influence of a human is required every time an error occurs.

[@shawnballee6053]

we really have no enrollment in electronics lately (I teach industrial automation).

[@bigbadtech]

Are you US based? If so give me a shout at my Columbia Gorge Community College email address. Got some good stuff for you.

[@sudhiracharya1234]

hi good topic, i am writing C program for closed loop pid algorithm for servo valve...I am having some doubt.

[@tigerider1663]

I enjoy your videos and they have helped out alot. Could you or have you done a video lecture yet for slip in cartridge valve technology?

[@bigbadtech]

Not yet. This is a worthy topic for the future.

[@tigerider1663]

Thanks, i look forward to it.

[@pawanvishwakarma8073]

Very good lectures of Hyd.system

[@signinprabu]

Can we do null setting manually or need to do it through proportional valve controller

[@ketel556]

How about PWM /dither freq. Great info in this video. It is excellent.

[@bigbadtech]

Working on finishing up the basic electronics series right now but yes I do plan on returning to pwm control and more.

[@SohanRoyroysohan]

Add this in your hydraulics training playlist

[@bigbadtech]

True. This should go at the end.

[@mumuwedding8056]

Can you explain the difference between proportional and servo valves?

[@Mech.Masters]

Servo valves are flow rated at 35 bar pressure drop per spool land. Maximum transmission of power from pump to cylinder occurs when pressure drop through system is 1/3rd of system pressure. Can anyone explain the meaning of these two sentences with practical methods to cross check the above two things ?

[@signinprabu]

Please tell me how to set a null setting in proportional valve

[@danalex2991]

Hi Jim How easy is it to program a servo valve to follow a specific displacement curve for many repetitive cycles for say about 10000 cycles. I recently did a plc program to program on off valves for cylinder testing and circuit turned out to be quite complicated for me anyways. It's on my channel if you want to see it . But I was wondering how much more harder would it be to program proportional valves and can we do it using plc ? Thank you

[@bigbadtech]

The PLC would necessarily have to be capable of producing an analog (ie: continuously variable) output to drive the proportional valve input (not necessarily directly, it may require some form of conversion, ie: 0-10V PLC output converted to 4-20mA proportional valve input). It's entirely possible to do this, however, as you discovered, nothing is ever easy! I'll check out your channel.

[@jamesscott6753]

might wanna specify that a proportional valve may be for flow or pressure control, the visual in the beginning is a little misleading.

[@signinprabu]

Please tell is there any null position setting is in proportional valves

[@bigbadtech]

If the valve is closed center an application of no control signal should result in no flow (minus leakage).

[@signinprabu]

@@bigbadtech here we are using a proportional valve in thermal power plant which is controlled from control room the problem facing is when the actuator is in fully closed condition some times it's slightly opening for some 0.6-0.8mm then again we are giving closing command it closing again but it's happening again and again. What I suspect is the null setting of proportional valve is slightly disturbed..is it right... And another thing is please tell me how to set the proportional valve NULL setting...

[@motti9000]

hi, can you pls explain me how the servo valve operates? how the fluid flow inside it? I have servo valve issus. NSN 4810-01-239-4114 . it works - the piston moves when I apply 28v but there is no flow. when I clean it from oil then it works for another two hours then the fluid not flow again. can the rubber seals ecan cause it? or dirt ? why there is tunnel in the piston and the electro magnet shaft? I will be more then happy to send you some vids and photos. tnks Motti.

[@Newera2047]

Hi Mr. Jim Pytel, I wanted single cylinder for press brake,tonnage is 15 ton and movement is 150 mm accuracy is 0.1 mm and using proportional valve with 2 different speeds design pls help me to design full setup I will pay consultant fee for your support Thanksgiving Regards Prakash SPM Technologies Bangalore India

[@veegee24]

Your statement at 1:29 is false. This is only true for open centre valves with fixed-flow pumps like gear pumps. If you have a variable piston pump and closed centre valves, there's nothing "spilling over" the pressure relief valve because the pump maintains constant pressure.