This is mind blown. I always thought the relief valve opens only when the system pressure is greater than the spring setting. I never knew that the relief valve drains some oil to the tank even if it has not reached the setting of the spring. But what causes the relief valve to crack open even though the spring is set to a higher setting than the system pressure
I'll try to clarify a little. The relief valve does indeed open when the system pressure is greater than the spring setting. You have that precisely correct. The first pressure level where that happens in a relief valve that has only one spring and one poppet, is not the highest pressure that the system will reach. As the overloading happens elsewhere in the system, perhaps at a hydraulic motor that is powering an increasingly overloaded winch, the relief valve poppet (single) will continue to compress the spring. The spring will in turn be pushing back with more force as it is compressed. The flow through the relief valve will increase as the poppet opens wider, as the motor/winch is overloaded to a point where the relief valve, wide open, with the spring compressed, will be the easier path for flow as opposed to the overloaded motor and winch. The pressure reached at that moment when the poppet is pushing the spring as far as possible, will be the true 'setting' of the relief valve, as that will now be the highest pressure that the system can reach. I hope that help.
What happens if the relief valve is set to 1000 psi and the load also has 1000 psi? All of it goes through the cylinder and it will remain stationary to its previous position, right?
Drain pressure in many cases will be a value that is close to or the same as atmospheric pressure if the tank is vented. If there is a return line filter preceding the re-entry to the tank, then drain pressure might be 1 or 2 Bar (15 or 30 PSI) depending on the model of filter, and the spring tension in the bypass check valve within the filter housing.
my father has a hydraulic dump body on a Chevy 1 ton, it has always worked, now al of a sudden it will kill the truck motor if it is raised all the way or even if you put a load on it, it wont lift it and kills the truck motor, we changed the motor because someone told him it was the electric motor but still does it any suggestions
We have a system with operating pressure of 16 bars, but sometimes we do experience pressure burst on the line. Can a PRV solve this problem, if so what is the expected range of the recommended PRV. Thanks a lot
A relief valve is meant to prevent an over-pressure condition, yes. I cannot say what type of action will solve your line burst problem, because I do not know the cause. What type or model of machine do you have? For the sake of safety, please be very careful not to make any adjustments to your system without first obtaining hydraulics training. Can you contact the manufacturer of your machine for assistance?
Our programmers and animators build all our simulations from scratch, using web technologies like SVG and JavaScript. We don't use any off-the-shelf program or tool. If you'd like to browse all our hydraulic simulations, head on over to our website: www.lunchboxsessions.com/explore/hydraulics
New Holland LB75? I haven't worked with that model. Do you have schematics or any manuals? What is the issue that you are dealing with, that requires finding the relief valve? Has the system pressure been too low? Please be careful with any adjustments, and follow all manufacturer's safety recommendations.
Is the 1.position on the valve oriented correctly? The one with the crossed arrows? I can't see how that would work, even with a both-way pump (it would just result in the same movement of the cylinder). If this were the case (pump moving the cylinder with suction rather than building up pressure), would that movement be more difficult for the pump, or does it not matter weather it is moving load with positive or negative pressure? (If we put cavitation aside) It feels like the positive pressure is the only right way to go, but I can't really understand why.. Could you help me understand this please? Great videos btw, shame I just found you today
I also believe the arrows of the first position were drawn incorrectly. They do not use a Hydraulics software for these videos (it is done manually on Flash) so this kind of mistake may happen.
Yes, I just wanted to check with someone else because I wasn't sure as I was fairly new to hydraulics. By now, I am sure it is a 'drawing mistake' because they just put a random valve in for presentation. Great videos tho, they've helped me tremendously!
Ah, yep! Good catch. I'll let the team know, so they can flip that symbol around. I'm thrilled to see you're paying such close attention to our animations, and I'm glad they're proving to be helpful.
They've really been helpful, especially to understanding the 'more complex' systems where it's really hard to imagine what's going on inside. I bet you've saved many students from hours of torture, myself included. Thanks again!
from famous hydraulic valve maker Eaton, on page one, in a paragraph that begins with "Graph 1 is..." It's a good explanation. www.eaton.com/ecm/groups/public/@pub/@eaton/@hyd/documents/content/pct_273384.pdf
Sir I love your videos Kindly elaborate about CATRIGE VALVE Type REXROTH LC 25 DBW20 Logic COVER LFA IF YOU COULD PROVIDE YOUR MAIL I CAN SEND YOU MY HYDRAULIC DRAWING
We've just posted a 50-minute lesson about relief valve basics - enjoy! ruclips.net/video/p7SgxfEQd1o/видео.html
The best teaching video ever made.
concept 95%, explanation 95%, accent and voice 100% clear.... thank you sir great job, is it your real voice?
เหมือนกับว่าตอนเพิ่มน้ำหนักนั่นมีloadมากดไว้ ทำให้ต้องใช้แรงดันสูงมากๆในการส่งกำลังขึ้นไป แต่ตัวRelief Valveนั้นตั้งค่าสปริงให้แข็งที่ประมาณ 300 psi จึงทำให้แรงดันสูงที่พยายามไปดันของไหลสีฟ้านั้นdrainทิ้งผ่านRelief Valveไปเพราะสปริงนั้นสู้แรงดันไม่ไหว, พอตั้งสปริงให้แข็งขึ้นแรงดันที่ต้องdrainก็ต้องมากขึ้น ส่งผลให้มีความดันที่สูงพอจะดันของไหลสีฟ้าได้
THANK YOU FOR YOUR VDO :)
what software that you used for design that schematics ?
I hope you make a video of how the EFI pumped fuel system works. thank you so much :D :D
This is mind blown. I always thought the relief valve opens only when the system pressure is greater than the spring setting. I never knew that the relief valve drains some oil to the tank even if it has not reached the setting of the spring.
But what causes the relief valve to crack open even though the spring is set to a higher setting than the system pressure
I'll try to clarify a little. The relief valve does indeed open when the system pressure is greater than the spring setting. You have that precisely correct. The first pressure level where that happens in a relief valve that has only one spring and one poppet, is not the highest pressure that the system will reach. As the overloading happens elsewhere in the system, perhaps at a hydraulic motor that is powering an increasingly overloaded winch, the relief valve poppet (single) will continue to compress the spring. The spring will in turn be pushing back with more force as it is compressed. The flow through the relief valve will increase as the poppet opens wider, as the motor/winch is overloaded to a point where the relief valve, wide open, with the spring compressed, will be the easier path for flow as opposed to the overloaded motor and winch. The pressure reached at that moment when the poppet is pushing the spring as far as possible, will be the true 'setting' of the relief valve, as that will now be the highest pressure that the system can reach. I hope that help.
Great job ! Appreciated !
Thanks for sharing this video. Good work.
Thanks a lot for your efforts!
Thank you for tutor.
Sir it is suburb knowledge channel ....🚀
Excellent explanation. Thanks
Best explanation
very helpful,, thanks a lot
thanks a lot
What happens if the relief valve is set to 1000 psi and the load also has 1000 psi? All of it goes through the cylinder and it will remain stationary to its previous position, right?
sir I love your videos i require hydraulic pump reaper videos
Me too
great simulations! could you please explain a Pressure Relief Valve: Proportional Solenoid Pilot Operated?
So interesting
what is the name of this circuit simulator software?
muito bom
Explain Excavator swing circuit sir..
Great video. Though,what does drain pressure actually mean?
Drain pressure in many cases will be a value that is close to or the same as atmospheric pressure if the tank is vented. If there is a return line filter preceding the re-entry to the tank, then drain pressure might be 1 or 2 Bar (15 or 30 PSI) depending on the model of filter, and the spring tension in the bypass check valve within the filter housing.
How can I find a steam power engineering consultant ?
my father has a hydraulic dump body on a Chevy 1 ton, it has always worked, now al of a sudden it will kill the truck motor if it is raised all the way or even if you put a load on it, it wont lift it and kills the truck motor, we changed the motor because someone told him it was the electric motor but still does it any suggestions
Thank you
We have a system with operating pressure of 16 bars, but sometimes we do experience pressure burst on the line. Can a PRV solve this problem, if so what is the expected range of the recommended PRV. Thanks a lot
A relief valve is meant to prevent an over-pressure condition, yes. I cannot say what type of action will solve your line burst problem, because I do not know the cause. What type or model of machine do you have? For the sake of safety, please be very careful not to make any adjustments to your system without first obtaining hydraulics training. Can you contact the manufacturer of your machine for assistance?
what's this program called ?
thanks a lot😃😃
Our programmers and animators build all our simulations from scratch, using web technologies like SVG and JavaScript. We don't use any off-the-shelf program or tool. If you'd like to browse all our hydraulic simulations, head on over to our website: www.lunchboxsessions.com/explore/hydraulics
where is the pressure relief valve located on lb75 backhoe
New Holland LB75? I haven't worked with that model. Do you have schematics or any manuals? What is the issue that you are dealing with, that requires finding the relief valve? Has the system pressure been too low? Please be careful with any adjustments, and follow all manufacturer's safety recommendations.
Is the 1.position on the valve oriented correctly? The one with the crossed arrows? I can't see how that would work, even with a both-way pump (it would just result in the same movement of the cylinder).
If this were the case (pump moving the cylinder with suction rather than building up pressure), would that movement be more difficult for the pump, or does it not matter weather it is moving load with positive or negative pressure? (If we put cavitation aside)
It feels like the positive pressure is the only right way to go, but I can't really understand why.. Could you help me understand this please?
Great videos btw, shame I just found you today
I also believe the arrows of the first position were drawn incorrectly. They do not use a Hydraulics software for these videos (it is done manually on Flash) so this kind of mistake may happen.
Yes, I just wanted to check with someone else because I wasn't sure as I was fairly new to hydraulics. By now, I am sure it is a 'drawing mistake' because they just put a random valve in for presentation.
Great videos tho, they've helped me tremendously!
Ah, yep! Good catch. I'll let the team know, so they can flip that symbol around.
I'm thrilled to see you're paying such close attention to our animations, and I'm glad they're proving to be helpful.
They've really been helpful, especially to understanding the 'more complex' systems where it's really hard to imagine what's going on inside. I bet you've saved many students from hours of torture, myself included. Thanks again!
What the hell is cracking pressure, i've never heard of such a thing.
from famous hydraulic valve maker Eaton, on page one, in a paragraph that begins with "Graph 1 is..." It's a good explanation. www.eaton.com/ecm/groups/public/@pub/@eaton/@hyd/documents/content/pct_273384.pdf
LunchBox Sessions. I stand corrected.
Sir I love your videos
Kindly elaborate about CATRIGE VALVE
Type REXROTH LC 25 DBW20
Logic COVER LFA
IF YOU COULD PROVIDE YOUR MAIL I CAN SEND YOU MY HYDRAULIC DRAWING
thanks a lot