Thank you. I learned some philosophy as well. "Fear is an excellent motivator" . Your sense of humor is top notch. Great content, educative and helpful. What a time we are in. Where genuine knowledge and information is only imparted to those with money. To have you is a blessing for person like me. A big thank you. I always believed we as a species must share our knowledge with others without any expectations. If I had an opportunity I will pass on what learn to other being without monetory expectation. Thanks once again. I guess the big bang only happened for this moment.
I found a vid of yours as I was trying to figure out what's a good PRV value for my beloved 1956 Fordson Major's new loader hydraulics. By now I've watched several videos and I'm excited to learn more. Thanks for making these vids, mate. They are great! Cheers from Sweden
I think what youve done is great. One thing to consider though is that Closed Center has nothing to do with whether or not the ports are being blocked when the valve is in the center position. Also, you wouldn't use a fixed displacement gear pump with a closed center valve. Open or closed center refers to whether or not there is a fluid passage way through the center or middle of the directional control valve that goes through the valve and then to tank. Only open center valves will use a fixed displacement pump...99.99% of the time.
Mike stay in touch because I've got another lecture "Hydraulic Pumps" that I'll be posting shortly. I try to "compartmentalize" the lectures and progressively add more and more info as I go along and unfortunately I have to go back and correct some of the gross simplifications I make in early lectures.
I really appreciate the efforts that went into the detailing of your lecture video, i wished i could only subscribe more than once thanks a lot appreciate
I have learned much from your videos and I almost didn't want to say anything because I didn't want to come off wrong, but all of the log splitters I have used have used the detent side of the valve for retracting the cylinder. I assume some are probably built the other way, but for safety, I think it would be a bad practice.
Sir, these videos are terrific! There's a link to one in my college blackboard, and I immediately came to subscribe. I wish I'd found these when I started classes. Thanks for the awesome, well-explained info.
So, something I don't understand is, at around 14 minutes in you say that in the presence of an electrical signal, the valve shifts position to allow fluid to enter the rod end and retract the cylinder. Then you say that when the signal is lost, the valve changes position again to allow fluid to escape back to the tank. But the part that confused me is when you said, even if the signal is present, the loss of hydraulic pressure would see the spring apply the brakes- my question is, why would hydraulic pressure be lost if the electrical signal is still present, meaning that the pump is still sending fluid to the actuator to keep it retracted?
"fail safe" contains the word "fail" for a reason. Equipment can fail in some very strange ways. A common exaple where hydraulic pressure is lost but electral power is present, is the use of hydraulic pumps thats get their rotaional power from combustion engines. Think eathmoving equipment. When the engine runs out of gas, hydraulic pressure is lost, but electrical power is still present because of the battery.
Morning, Jim. I have two questions. First, I coundn't understand why the combination of a directional control valve and a pressure relief valve to dump the fluid back to tank is not a good option. And secondly, to an open center directional control valve do its job is not necessary two check valves blocking P to A and P to B ways?
I'm presuming you're first referring to a closed center directional control valve and pressure relief valve? In closed position pressure will always rise to setting of relief valve which opens and dumps to tank. This is like making a lot of money and then just burning it. An open or tandem center prevents this from happening by allowing a continuous low pressure relief path back to tank. No checks required for open center. Everything at tank pressure.
@@bigbadtech About the waste of energy using this configuration now I could understand. But I think when the pressure flow is applied in system the rod end and cap end sections along with the tank are filled with pressure flow, are not?
Unfortunately I don't really go into the internal specifics of poppet style valves because when viewed from the outside they're kind of functionally equivalent to a spool style directional control valves. I like to think of them as mini pilot to open or close check valves rather than sliding spools (or sliding plates) that selectively connect or disconnect the internal passages.
In a hydraulic directional solenoid valve symbol, if there is a colored triangle symbol next to solenoid symbol then such valves are called as Hydraulic Pilot operated solenoid valves. But my doubt is how does a solenoid valve operate on Pilot pressure, it operates only when we give electrical signal to the solenoids. Kindly help me to understand this.
The solenoid shifts the pilot, the pilot shifts the main spool. Often used when solenoid doesn't have sufficient strength to shift for high flow/high pressure applications.
Jim, Thank you great video. Jim do you have a video that explains, how a hydraulic / piloted derent actual works. By that i mean give an example of just what actually goes on inside the detent mechanism, when kickout pressure is reached. Could you show this for a 3 position, manual activated valve that shifts to neutral at kickout
Good question. Often times one doesn't even see a hydraulically piloted detent included in a simplified schematic but rather a simple statement specifying the kickout pressure. This being said some manufacturers do include it in a more extended schematic. Check out the bottom of page 2 of the Prince manual for the LSR-3000 regen valve: www.baileyhydraulics.com/pdf/ValvesLsRD25.pdf The detent is kind of like a little hydraulic cylinder acting against a bias spring. When pressure is less than the kick out the detent is in. When pressure exceeds the kickout the detent retracts.
@@bigbadtech Ahh so the ports being open doesn't necessarily mean bi-directional flow that makes perfect sense. Just finished this playlist, amazing content here man
All the study guides for the hydraulics lectures have been consolidated at openoregon.pressbooks.pub/hydraulics/ Stay in touch because I'm working on a similar project for basic electronics.
Thank you. I learned some philosophy as well. "Fear is an excellent motivator" . Your sense of humor is top notch. Great content, educative and helpful. What a time we are in. Where genuine knowledge and information is only imparted to those with money. To have you is a blessing for person like me. A big thank you. I always believed we as a species must share our knowledge with others without any expectations. If I had an opportunity I will pass on what learn to other being without monetory expectation. Thanks once again. I guess the big bang only happened for this moment.
I found a vid of yours as I was trying to figure out what's a good PRV value for my beloved 1956 Fordson Major's new loader hydraulics.
By now I've watched several videos and I'm excited to learn more.
Thanks for making these vids, mate. They are great!
Cheers from Sweden
Your content is extremely useful and awesome. Thank you!!!
SPECTACULAR lectures&explanations!!! ABSOLUTELY GREAT JOB! THANKS FOR WHAT YOU HAVE DONE IN HERE and for the help you provided!!
A big thank you from Ghana Jim Pytel
Very informative.. Am revising on hydraulics in preparation for an interview in the mines as a heavy duty mechanic..
All of your videos are very informative and easy to understand
I have fluid power exam tomorrow and here I am understanding the DCVs. Its a great video.
Good luck!
I think what youve done is great. One thing to consider though is that Closed Center has nothing to do with whether or not the ports are being blocked when the valve is in the center position. Also, you wouldn't use a fixed displacement gear pump with a closed center valve. Open or closed center refers to whether or not there is a fluid passage way through the center or middle of the directional control valve that goes through the valve and then to tank. Only open center valves will use a fixed displacement pump...99.99% of the time.
Mike stay in touch because I've got another lecture "Hydraulic Pumps" that I'll be posting shortly. I try to "compartmentalize" the lectures and progressively add more and more info as I go along and unfortunately I have to go back and correct some of the gross simplifications I make in early lectures.
One of the best presentation on dcv. Awesome effort.
Nothing I love more than the ability to work in calling someone "peasants" into a discussion. Well done.
I really appreciate the efforts that went into the detailing of your lecture video, i wished i could only subscribe more than once thanks a lot appreciate
Glad you're making use of this material. Check out the newly published pneumatics bonus round at: th-cam.com/video/Npu9uJYDI2k/w-d-xo.html
I have learned much from your videos and I almost didn't want to say anything because I didn't want to come off wrong, but all of the log splitters I have used have used the detent side of the valve for retracting the cylinder. I assume some are probably built the other way, but for safety, I think it would be a bad practice.
Sir, these videos are terrific! There's a link to one in my college blackboard, and I immediately came to subscribe. I wish I'd found these when I started classes. Thanks for the awesome, well-explained info.
Very nice! Please tell members of your class, instructors, and first year students these free resources exist.
Appreciate the work invested in your videos ! You deserve much more subscribers
Make sure you tell your friends this resource exists!
@@bigbadtech i will do, this was awesome.
This is what I was looking for.... thanks a ton
its good video hard work for more videos
Love the beats on the intro. The content is awesome too
+carrrake What is the instrument and what martial art is it associated with? 10,000 bonus points at stake.
@@bigbadtech Berimbau-Capoeira
Em cada som, em cada toque, em cada ginga, tem um estilo de jogo! 10,000 points!
Nice explanation........Thank you
thank you for the lecture. sir.
Very informative, Thank you
So, something I don't understand is, at around 14 minutes in you say that in the presence of an electrical signal, the valve shifts position to allow fluid to enter the rod end and retract the cylinder. Then you say that when the signal is lost, the valve changes position again to allow fluid to escape back to the tank. But the part that confused me is when you said, even if the signal is present, the loss of hydraulic pressure would see the spring apply the brakes- my question is, why would hydraulic pressure be lost if the electrical signal is still present, meaning that the pump is still sending fluid to the actuator to keep it retracted?
Loss of pressure means the pump is disabled.
"fail safe" contains the word "fail" for a reason. Equipment can fail in some very strange ways.
A common exaple where hydraulic pressure is lost but electral power is present, is the use of hydraulic pumps thats get their rotaional power from combustion engines. Think eathmoving equipment. When the engine runs out of gas, hydraulic pressure is lost, but electrical power is still present because of the battery.
Thanks a lot!
Morning, Jim. I have two questions. First, I coundn't understand why the combination of a directional control valve and a pressure relief valve to dump the fluid back to tank is not a good option. And secondly, to an open center directional control valve do its job is not necessary two check valves blocking P to A and P to B ways?
I'm presuming you're first referring to a closed center directional control valve and pressure relief valve? In closed position pressure will always rise to setting of relief valve which opens and dumps to tank. This is like making a lot of money and then just burning it. An open or tandem center prevents this from happening by allowing a continuous low pressure relief path back to tank. No checks required for open center. Everything at tank pressure.
@@bigbadtech About the waste of energy using this configuration now I could understand. But I think when the pressure flow is applied in system the rod end and cap end sections along with the tank are filled with pressure flow, are not?
Remember that pressure requires resistance to flow. Any open path to tank implies no resistance and low pressure.
Hi Jim, great job. Just wanted to know if you have anything related to Poppet (Cartridge) Valves with some circuit examples.
Unfortunately I don't really go into the internal specifics of poppet style valves because when viewed from the outside they're kind of functionally equivalent to a spool style directional control valves. I like to think of them as mini pilot to open or close check valves rather than sliding spools (or sliding plates) that selectively connect or disconnect the internal passages.
Wow thanx dawg ✊✊✊
You're welcome. Please tell your friends about this resource!
goooooooood teach sir
What would the technical name be for a 3 position control valve with that built in flow meter modifier that you touched on at minute 33?
This would be considered a proportional or "servo" valve. Got a whole lecture at: th-cam.com/video/wsJK0N50Xxc/w-d-xo.html
hello sir. i am very thankful to you. is its PDF available?
Everything you need and more is right here ... openoregon.pressbooks.pub/hydraulics/
@@bigbadtech this site can't be reached sir
Just checked. This site is functional openoregon.pressbooks.pub/hydraulics/
Got it sir ... thank you
@@bigbadtech OK.it has opened..thanks alot
Thanks
In a hydraulic directional solenoid valve symbol, if there is a colored triangle symbol next to solenoid symbol then such valves are called as Hydraulic Pilot operated solenoid valves. But my doubt is how does a solenoid valve operate on Pilot pressure, it operates only when we give electrical signal to the solenoids. Kindly help me to understand this.
The solenoid shifts the pilot, the pilot shifts the main spool. Often used when solenoid doesn't have sufficient strength to shift for high flow/high pressure applications.
Jim, Thank you great video. Jim do you have a video that explains, how a hydraulic / piloted derent actual works. By that i mean give an example of just what actually goes on inside the detent mechanism, when kickout pressure is reached. Could you show this for a 3 position, manual activated valve that shifts to neutral at kickout
Good question. Often times one doesn't even see a hydraulically piloted detent included in a simplified schematic but rather a simple statement specifying the kickout pressure. This being said some manufacturers do include it in a more extended schematic. Check out the bottom of page 2 of the Prince manual for the LSR-3000 regen valve: www.baileyhydraulics.com/pdf/ValvesLsRD25.pdf The detent is kind of like a little hydraulic cylinder acting against a bias spring. When pressure is less than the kick out the detent is in. When pressure exceeds the kickout the detent retracts.
how modular valves operate ?
31:37 shouldn't these arrows be bi-directional then?
Yes, however they're ordinarily not intended for bidirectional operation as there are dedicated P, T, A, and B ports.
@@bigbadtech Ahh so the ports being open doesn't necessarily mean bi-directional flow that makes perfect sense. Just finished this playlist, amazing content here man
is there any pdf for your lectures please
All the study guides for the hydraulics lectures have been consolidated at openoregon.pressbooks.pub/hydraulics/ Stay in touch because I'm working on a similar project for basic electronics.
Put another way, open center and closed center are two variables that have nothing to do with your spool configuration.
Tq
Porque no lo traduce al español ,gracia