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Need guidance for my first hydraulic cylinder

1759 Views 7 Replies 5 Participants Last post by  Alan_Heist
I am going to purchase a hydraulic cylinder or two in the upcoming months. I have never worked on one.

What I have is a Kolpin dirt works 3pt electric actuator hitch. I love the fact that it can come off and on. However the electric actuator leaves something lacking for power and speed.

I want to switch that electric actuator over to a hydraulic cylinder and operate it off the bottom ports on my JD 425 or my JD x700.

I have installed air systems, not sure if hydraulic is much different? If it was air, I would install male couplers on a couple of hoses, then run it to the back and put in female couplers on the rear for quick hook and disconnect.

What I really need someone to explain, is I know there are 2 hoses for hydraulics, in and out, any more in depth might be beneficial.

Also can you extend hyrdraulic lines line air lines? Would my idea work?

I also have a rear blade that I want to put sides on with a cylinder and make it a box scraper to grade the driveway. So there's cylinder #2.

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Don't use air stuff with hydrolics... They cant take the pressure and something bad will happen...
I wasn't planning on using air conncectors. However is the systems similar that you can make your own hoses and use quick connects for hydraulics?
The short answer is "YES".

Air sytems fittings and compoments are generally restricted to a design limit of 600 psi. Hydraulic systems can go waaayyyyy beyond that pressure. Since air is compressible, shock loads are not generally a big deal. Hydraulic fluid is generally accepted as incompressible, making shock loads a very big deal. A 700 psi GT hydraulic system, such as you are contemplating, needs components, hoses, and fittings rated somewhat higher than relief pressure. Hoses in particular come in several pressure ratings and 2500 psi hose would be my recommendation for any system up to 1800 psi.

Hydraulic fittings are an education all by themselves. Click Products and then Fittings on this link.

Here's a hydraulic primer.

Think of the hydraulic hoses as the 2 wires in your home electrical system. Air systems do the same, except the second hose is eliminated and the air gets exhausted to atmosphere. Basically the same plumbing arrangement as an air system, with the addition of the return line, and the only place to use teflon tape is on tapered pipe threads, never on any other type of hydraulic threads.

Your plan is a good plan, with the addition of a pair of control valves. Any unused ports can be plugged until you add the second cylinder. You might consider adding coloured tie wraps to the quick connects to keep straight what plugs in where. There should be no specialized parts to worry about. Most hydraulic shops will carry what you need and can make up the hoses for you. There are re-useable hose fittings available so you can make up your own hoses, but there is a learning curve involved. It can be frustrating the first time or two, and any savings over professionally made up hoses are questionable. Re-useable hose fittings are quite a bit larger than crimped on fittings and space is sometimes at a premium.

This all assumes that the ports on the hydro that you want to use are there for this application and that the correct relief valve has been installed.
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Wouldn't quick disconnects tend to introduce air into the system requiring bleeding each time they are disconnected and re-connected?
No. There are check valves in both halves of the quick connectors and very little, if any, air can get in.

The way to bleed air out of a hydraulic system is to use it. Eventually, the air gets moved back to tank and promptly becomes a none problem. Usually it only takes a couple of full strokes of the cylinders.
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Thanks. I learned my lesson for the day. I can rest now. ;)
Thanks. I learned my lesson for the day. I can rest now. ;)
That's funny right there... I don't care who ya are... :sidelaugh
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