How to make hydraulic valve?

[jazza]

Can any once tell to me, How i can make hydraulic valve? or post assembly image of it.

Thank in advance.

[Jw.]

Hey Jazza check out Trucker47's thread on his loader. Page 4 and Page 5 has photos of his whole hydraulic setup he homemade.
http://www.rctruckandconstruction.com/showthread.php?t=3260
http://i345.photobucket.com/albums/p398/trucker-47/IMG_6171.jpg

[RCP57]

That is much the same as what I have built. There are other styles out there too but this type(rotary) is quite common.
http://i1293.photobucket.com/albums/b588/RCP57/IMG_1619.jpg
http://i1293.photobucket.com/albums/b588/RCP57/IMG_1622.jpg
http://i1293.photobucket.com/albums/b588/RCP57/IMG_1626.jpg
http://i1293.photobucket.com/albums/b588/RCP57/IMG_1625.jpg
http://i1293.photobucket.com/albums/b588/RCP57/IMG_1624.jpg
http://i1293.photobucket.com/albums/b588/RCP57/IMG_1623.jpg

Reg

[Jw.]

Valves for our applications are normally fall under the 5/4 port 4 way 3 position setup. As in this picture below trying to explain the ports. Its of a spool valve to get backward and forward control of a hydraulic circuit. I recommend going with the rotary valves shown above. They have the same fluid control but tolerances are easier to obtain than a spool setup. Also I recommend a closed center position so your hydraulics will not creep. How you make each valve is up to you. Individual depending on your application or together on a manifold with pressure and return circuits built in like RCP57's really nice manifold set up.

Ps Pressure from your pump
Pr X2 Return circuit. Combined on a rotary valve. Seen on the above pictures.
Pa and PbYour lines to both sides of your cylinder.


http://i784.photobucket.com/albums/yy130/jp7986/DVHFigure4_zps5477f7fc.png

[jazza]

Thank you all answer, It's really help me.
Can any once post the rotary valve blue print?

sorry for my more question, I'm a newbie :)

[cosworth34677]

i quite don't get the layout of that pic? i want to make my own vale too. and really having a time with all the hydraulic stuff, price and understanding (pulling hair out)

[Jw.]

Please excuse my poor cad abilities as I'm still trying to learn. This is the manifold I quickly drew up to help explain.


http://i784.photobucket.com/albums/yy130/jp7986/valve222_zps61eba1d1.jpg

http://i784.photobucket.com/albums/yy130/jp7986/Valves333_zps2e5ef95b.jpg

[RCP57]

Looks pretty clear to me! Nice drawing.

[Jw.]

Looks pretty clear to me! Nice drawing.
Thanks! I eventually will be attempting this myself at some point. What did you end up having as a diameter for your valves? I read through your thread and you ended up making them smaller than you original planned. It looks like your manifold is steel? Whats the valve body? Aluminum? Also what did you use for seals?

I spent some more time in cad came up with this.
http://i784.photobucket.com/albums/yy130/jp7986/RotaryValvewithlinesfinalcutoutsDEMOhalf123456_zps 5fe7e768.jpg

[Madda]

Jw., good job on the drawings!


One thing that I'm not really sure of is where and what seals are used?

[ihbuilder]

JW : steel or iron next to brass would be the best choice for your manifold . Aluminum does not wear well .


Madda : O-rings work well for the seals as you should only have to seal the shaft of the rotor and the rotor cap . between the rotor and the valve block , you should have a lapped fit .

[RCP57]

JW : steel or iron next to brass would be the best choice for your manifold . Aluminum does not wear well .


Madda : O-rings work well for the seals as you should only have to seal the shaft of the rotor and the rotor cap . between the rotor and the valve block , you should have a lapped fit .

I agree with Steve 100%. The valve that I made for my skidder is all aluminum with brass rotors but it may not last long. The valve block that my father in-law made for my EC300DL has a steel manifold and should last much longer. The shafts are sealed with common O rings on both. The EC300 runs at 30-35 bar with no leaks on the valve shafts.

[RCP57]

This is the only picture that I took of the Volvo's valve assembley. I believe the pistons in this are .550. In mine they are slightly larger at .610.
http://i1293.photobucket.com/albums/b588/RCP57/IMG_0990_zps436361cb.jpg

[ihbuilder]

even with the poor tolerances on the Robbie valves , they don't leak . The rotor just chews up the manifold . When I get back to running steel in the mill , I'll be making 2 , 1 for the loader and 1 for the TD40 .

[cosworth34677]

so this is all steel? i want to try to make one of these, but i only can cut aluminum on the router table at work. can i use plastic on any parts? and why not aluminum? thanx for the thread guys lot of good info !!

[RCP57]

so this is all steel? i want to try to make one of these, but i only can cut aluminum on the router table at work. can i use plastic on any parts? and why not aluminum? thanx for the thread guys lot of good info !!

The top of the valve in the last pic is aluminum but the bottom is steel. I think that aluminum is "ok" as long as your rotors are made of brass or steel. Aluminum rubbing on aluminum will gall up even with oil in there. Aluminum just wears quickly and won't maintain the tolerences needed for very long. Plastic would not be a good choice in my opinion.

[cosworth34677]

so what if you put some kind of "buffer" between the Aluminum? like a brass thin shim or washer? of even a brass gasket? the only reason i ask because again i only have the abillaty (<---spelled wrong) to cnc aluminum? the cnc router at work will only route softer metals only because of our bits. and the boss won't let me cut steel on it i asked before for parts for my real car.

[Finster]

Perhaps some automotive gasket material between the 2 main pieces would work?

Like: http://www.autozone.com/autozone/accessories/Fluids-and-Chemicals/Gasket-Material/_/N-25w7

[jazza]

Thank all for you help me.

[Newcastle]

When designing the valve say at 10mm and the valve body how much clearance should you give? Would you do the valve body at maybe 10.1mm?

[550166681]

very good ！

[thetractorfan]

Please excuse my poor cad abilities as I'm still trying to learn. This is the manifold I quickly drew up to help explain.


http://i784.photobucket.com/albums/yy130/jp7986/valve222_zps61eba1d1.jpg

http://i784.photobucket.com/albums/yy130/jp7986/Valves333_zps2e5ef95b.jpg

Thank you so much. I looked all over the Internet for cheap hydraulics and I was supprised to see how expensive hydraulic valves are. Many places charged into the hundreds in Euro's just for a 2 way valve and the models I want to build need many more valves and components which weren't getting cheaper.

[Cat966c]

Could I use plastic for the valve rotor?

This thing:

[Cat966c]

Grrrr. The thing in the bottom pic in the post above

[skeeter]

I would ill advise it. I'm no hydraulic expert, but I do know I've experienced an RC machine that had plastic incorporated into the valve design. It wasn't long before it leaked & was useless. I wound up buying a valve spool from Magom in Spain to remedy the manufacturers crappy designed valve.

[Cat966c]

Thanks!

Ah, darn ��

What about the valve itself (thing the rotor sets in) could it be plastic?

[skeeter]

I wish I were more help. I know limited amounts about hydraulics. Alls I know is I threw away the plastic crap that was causing the issue & upgraded it to a full metal valve spool.

[Cat966c]

Nah man, you’re a big help-thanks! �� :D

[frizzen]

Maybe some kind of ultra high molecular weight plastic? You'd probably spend more and longer trying to find a plastic that's stable enough at pressure. Looks like the RC systems keep it under 500psi, so it's not too crazy, but trying to figure out forces doesn't sound fun.

Can your tools run Brass?

Maybe go Aluminum for the valve body, but i might be concerned about galling if you run aluminum for both the block and spool though.
Might be able to add some teflon sheeting at the faying surfaces without very much redesign, then surface finish in the block wouldn't be quite as critical.

Might want to check around your local machine shops, if you've got a small one that does one-off stuff they could be a big help. But you also might find a production valve system price is close to theirs anyway...

*not a machinist at all. I just have decent grasp on theory, and operate some high pressure stuff*