Cylinder Drift

If you remove the piston seal from a hydraulic cylinder, it will drift out of position, right? Not necessarily! Find out why in this week's Live Schematic screencast, then head to www.lunchboxse... to register for a whole ton of learning media like this.
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[@uthanwintun]

Really happy to see this video. I have been arguing with workmates over years who always blame cylinder when they are creeping. Simply barrel has no more space to accommodate rod's volume unless oil escape through valves or rod wiper seal or head. Thanks buddy.

[@mike93eh]

BUT cant the rod extend out?? less volume drifting out

[@bhstor0]

It won't drift but it will be due to vacuum instead of higher pressure.

[@Teddy_Bass]

This channel is pure gold. Really decent stuff

[@philliplucion4262]

I'm a mechanic in the mining industry and our continuous miner has this problem with the head drifting they have changed Jack's but it is a remote operated machine I think a lot of the drift in this machine comes from worn out solenoids in the controller mounted to the valve chest so be adjust on that this evening and I'll let yall know how that goes. Good video also thanks for the diagram

[@t4sturm]

these are the some of the best videos i have seen on KZbin. Please keep making more!!!!

[@lunchboxsessions]

Thanks - and don't worry, we're going to keep on making these videos! If you want to support us, just help spread the word.

[@Engineerboy100]

I have to agree, I'm a mechanical engineer and these videos are helping me understand a lot of things that were not fully explained in college .... gotta learn a lot of things on your own if you want to be good. :)

[@victorrosero3206]

@@lunchboxsessions Excelente video , podria decirme el nombre de el programa que usa y donde puedo comprarlo para fines educativos ,muchas gracias .

[@roseelectronics4582]

Really helpful! I thought the piston rod will slide down all the way to the bottom once the piston seal was removed. The nice graphics and your clear explanation made me grasp the concept pretty easily.

[@nathanares5233]

You all prolly dont give a damn but does anyone know a trick to get back into an instagram account? I was stupid lost my password. I would appreciate any assistance you can offer me.

[@charlessalvador7251]

@Nathan Ares instablaster :)

[@nathanares5233]

@Charles Salvador I really appreciate your reply. I got to the site thru google and Im trying it out now. I see it takes quite some time so I will get back to you later with my results.

[@nathanares5233]

@Charles Salvador It did the trick and I now got access to my account again. I'm so happy:D Thank you so much, you saved my account!

[@charlessalvador7251]

@Nathan Ares you are welcome :)

[@simclardy1]

Found my bobcat lift arm drift with this knowledge. The emergency arm release valve was leaking. Great videos!

[@krish08111994]

Are you able to elobrote the way you solved. Kindly need your support.

[@simclardy1]

@@krish08111994 I used an ultrasonic leak detector with a contact probe to listen for flow/ turbulence. I think you can use a simple mechanic stethoscope. it was my bobcat t190 2007 machine. next to the seat on the right you have an emergency release valve to lower the arms and that was leaking. cheers

[@simclardy1]

This is excellent! My bobcat has drift and this video would have saved me some time and money!

[@DAS-Videos]

Interesting. It is like trying to pull out the plunger of a syringe while your thumb is covering the air hole. Except the seal would be at the top, not against the cylinder walls. So for creep to occur, more oil must be able to get pulled into the cylinder.

[@gauravbutle2429]

Sir what about 2nd condition you mentioned (hanging load)

[@SteveWrightNZ]

System Designers might take note of the dangerous amplification of cylinder pressures accompanying that seal failure - since the cylinder pressure will now be set by the rod diameter, not the piston diameter OR the relief pressure. Possibly 3-5 times the cylinder pressure now evident, and over the entire canister. For machinery expected to support heavy loads, a factor of safety of 2-3 based on the rod diameter is a much larger cylinder. Add to that, a pressure relief device or any other device inside the valving will have to contend with 3-4x it's normal operating conditions, possibly leading to an uncommanded lowering, even, unexpectedly, via the rod-end port. No one saw that coming... :/

[@ZacharyPiercy]

Yes that’s a very important nugget of information that is easily glossed over from this situation, thanks for emphasizing it here.

[@aevitasfitness7867]

Did you post a cylinder drift in extension video?

[@jmc6940]

Were is the video with cylinders drifting outward?

[@ShreddinSleds]

Did you ever end up doing a video on cylinder drift in the retract direction? I ended up working on a telescoping forklift and with the machine shut off the boom would extend. This cylinder has holding valves so another test we did was capping the cylinder off completely and it would still drift out.

[@bhstor0]

I would suspect air is getting sucked into the cylinder. Pulling the rod out would create a vacuum.

[@Engineerboy100]

Love these videos, I'm learning so much, I'm binge watching lol thanks

[@F47451]

Your simulation is wrong. If no seal the piston will slowly drop down because the upper force still exist, but no static counterforce anymore.

[@DeyanYakimov]

It is not true. In order to dip more of the rod inside the cylinder, some oil need to evacuate. I am sure that if we start heating the cylinder the rod will even moves out in order to compensate expansion of the hydraulic oil. It will worth to see simulation like this.

[@F47451]

​@@DeyanYakimov If no seel an oil can move between top and bottom chambers can't it? Simulation works wrong because inside diameter of chamber and outside diameter of cylynder are set equal. In practice the piston is always slightly smaller.

[@DeyanYakimov]

@@F47451 If there is no seal oil can move, but only if the rod seal is also leaking. In order to push the cylinder in, you need more space inside to accomodate that part of the rod that is still outside - but the space is limited (oil cannot be compressed). If there is no rod, bud only piston it will slowly drop down. Watch the video once again carefully and you will understad.

[@F47451]

@@DeyanYakimov Yes you are right. I did not carefully watch the video. Thank you a lot!

[@ericklascaibar9900]

Why does the piston drop slight when the seals are removed? If F=PA and the area on the bottom of the piston is larger than the top, shouldn’t the force be moving up?

[@skunkjobb]

It would have been more pedagogic if it was orange color below the piston before you remove the piston seal and then change to red in the whole cylinder. That would better show that the pressure will (depending on piston rod and piston diameter) increase substantially in this situation when the seal starts leaking or is removed. Now we can se a slight increase on the lower gauge but changing colors would be even better.

[@laneburgess1643]

Amazing videos, please keep making them. I have not been able to locate the other video on extension drift.

[@MarceloMouraMG]

I was looking for it as well. Will it be done?

[@vasukaneriya4182]

Which software are you using for diagrams?

[@Joetime90]

What if the gland seal is leaking, but the piston seal is good? Or would a bad piston seal eventually stress the gland seal to failure?

[@AmanSharma-nw4ym]

Sir what will happen if there dubble acting cylender is?

[@ORingmaintenance]

When will the site be opened to the public ?

[@lunchboxsessions]

We're planning on a full public launch later this fall. If you register at the website (www.lunchboxsessions.com) then we'll send you an email when the time comes. Cheers!

[@AS-wi6hr]

What simulation software is this??? It's amazing!!! 😮 {if it's not just an animation that is}

[@mohamedsabra8481]

great video but you only simulated cylinder 1 what about cylinder 2 with a hanged load? will it be like the first cylinder or not.

[@mikehawk4517]

My guess is that it would be the same thing. The only difference is that the cylinder pressure would be at vacuum instead of high pressure.

[@mike93eh]

YES!!! that is the exact problem im having that i cant find any info on whatsoever!!

[@haristyaardyanto8237]

What application did you use to make this animated diagram sir

[@austingim]

Thank you so much sir, for this amazing video, you save my job

[@rottmanthan]

i thought for sure without the seal the piston would make its way down and the fluid below would make its way above the piston.

[@rafailg2151]

Can you suuggest me a handbook about hydravlic systems???? Thnaks

[@cono1121]

I had an outrigger on a truck mounted crane system that would extend down just fine, but would go back up if I used any other controls. only one of the outriggers did this. Do you Have any insight as to what would cause this? im thinking a check valve of some sort

[@oneporttv4138]

Good day Sir. I hope that you can help me for this hydraulic tilt problem.. The problem is the tilt Authomatic release the pressure.. What is the solution for that Sir.. Please give me idea to fixe this problem. Thank you.. God bless...

[@ZULFERISYAHPUTRA]

Dear Sir............Example Problem I have a single acting hydraulic cylinder with a stroke of 300 mm, a bore of 18 mm and a rod of 10 mm if the press weight is 10 mm on the Piston Head what is the pressure.....Please explain the calculations

[@StormTrouper3]

I learnt something new.

[@Bikemad24]

Do you answer questions?

[@705richard]

How about proper testing procedure for piston seal by pass

[@rammsteinlim3057]

Hi everyone,,,,i want to ask what is the problem of my pc60u backhoe komatsu.the cylinder boom in bucket if you going (out) the rod ok,but if you shift to (IN) the rod the engine become to shout down or off,,,please help me,,,advance tnx

[@topspeederalmond]

THANK YOU

[@beeruhatti1987]

THANKS FOR UPLOADING THIS VIDEOS

[@rayedge1802]

Good Video, I have a an issue with my main up/down cylinder on my Versalift Bucket van. When I toggle the cylinder up it goes up and when I toggle down it goes up. Everything in the tower checks out so far but I haven't done any troubleshooting on the cylinder since it wasn't visibly leaking . Could the internal seals be gone making it go up on both movements?

[@krish08111994]

Shall I Know how the solution happened

[@TrueBlueYukoner]

Awesome; Even trained hydraulic Techs don't understand this.

[@dman2188]

What is the name of a valve i can use to stop cylinder leak down if a hose breaks ..such as in a crane ?

[@1pollo1rabbit]

d man Holding valve or counterbalance valve.

[@joehunt3512]

I have a cylinder at work that drifts back to extended.

[@supriokb398]

Great video... Learned a lot....Can you tell simulation software U guys have used for this?

[@lunchboxsessions]

Hi Suprio. Our artists and programmers make these simulations from scratch. To learn more about Live Schematics, check out our company site: www.cdiginc.com/live-schematics

[@AmanSharma-nw4ym]

@@lunchboxsessions sir what will happen if there dubble acting cylender is?

[@SuperSwapnil1990]

could you help with hydraulic power pack circuit working

[@lunchboxsessions]

Is there a specific feature on your power pack circuit that you are curious about? Does it have a fixed displacement or variable displacement pump?

[@SuperSwapnil1990]

hello sir , i want to know how pressure and flow are fixed on a rexroth hydraulic powerpack . it has an axial flow piston pump with 9 pistons.

[@lunchboxsessions]

Ah yes I understand. I recommend that you view our videos kzbin.info/www/bejne/oJSmeGmvf9xkfLs and also kzbin.info/www/bejne/lZbIeaB7Ysl7hs0 These two videos cover the topics you are inquiring about. Most models of Rexroth, 9 piston axial pumps will be the same or very similar to what is described in these videos.

[@Meothui1236]

Pumps concrete??

[@Habib.1992]

Thnx bro

[@mzee5533]

Just and counter balance valve

[@adik9441]

super

[@celsobaronedemelloesilva7837]

Excelente! aula muito obrigado.

[@thinhpham3683]

What is the name of this app?

[@lunchboxsessions]

See here: www.lunchboxsessions.com/help/what-software-do-you-use-to-make-the-simulations

[@Jan-nl8kg]

This cannot be true, removing the piston oring sealing will make the piston rod "slowly" sink with equivalent velocity set by the clearance of the piston and cylinder inner diameter, due to the force F from the load.

[@josueamparo1677]

I wish my professor taught us like this

[@tengkuaminuddin8079]

Hi. From Baker Hughes =p

[@lunchboxsessions]

Great to hear from you Tengku!

[@smoothntallGWM]

Please remove that annoying soundtrack... it's distracting from the spoken words.

[@lunchboxsessions]

Thanks for the feedback. Most people barely notice that background sound, so it's helpful to get some feedback suggesting that it's too prominent. We're planning to revise how we do sound production, so you'll probably notice some improvements in our future videos. I hope that despite the sound, you're able to get some useful information out of our existing videos. Cheers.

[@ashik1ka]

🤝🤝🤝

[@DavidSedano-mh4ep]

Blah blah blah job blah read blah job blah school