360 rotation on mini excavators

[gmwest80]

I am trying to learn more about the component that provide the 360 rotation on a mini excavator, but also provides hydraulics to the final drive track motors as well. I no the bigger units use a rotating union, but wasn't so sure about the smaller units such a the Case C series. I have tried looking on the internet, and what information I have found has been somewhat ambiguous. Any direction are help is greatly appreciated. Thanks

 

[CincyFlyer]

There are a very limited number of ways to do this! I assume that you have something in mind; perhaps if you let us know what it is, we can give suggestions.

 

[Fallon]

How Do Rotary Unions Work? - YouTube

 

[DJ54]

Go here: CASE Construction Equipment US | Heavy Equipment and Light Equipment and do a parts search (under solutions in the menu at left side) for the model you're looking for. Each component of the machine will be shown in an exploded view, so I ought to be pretty easy to figure it out.

 

[gmwest80]

There are a very limited number of ways to do this! I assume that you have something in mind; perhaps if you let us know what it is, we can give suggestions.

I am basically interested in building a mini excavator, and I am wanting to find that particular component off the shelve from a name brand. If that makes since. Thanks for replying sir

 

[gmwest80]

You are correct, not hard to find that part, it just that when I saw as the swing motor for the mini excavator C series, it looked nothing like the rotating unions that the bigger machines have, which made me question if track motors were fed the dydraulic fluid another way besides the swing motor. Hope that makes since

 

[4570Man]

I played around with the idea of building a mini excavator. My plan was to have 360 swing just not continuous.

 

[bigdeano]

The swing motor is a different part than the rotary union I'm pretty sure. The swing motor oil wouldn't have to go thru the rotary union. The swing motor would be mounted on the upper part of the machine and drive a gear on the bottom part. The only oil going thru the rotary union would be for the travel motors.

 

[gmwest80]

So would it be correct to say, that even the small excavators have rotarty unions, same as the big units?

 

[CincyFlyer]

So would it be correct to say, that even the small excavators have rotarty unions, same as the big units?

It would be safe to say that if the unit had true continuous rotation. I saw a tiny fabricated unit that could only do about 300°, and it just had a little extra hose to allow that. If push came to shove, and you have a lathe, you could make a four-port rotary union, but I'd look for something like this first, if it wasn't too pricy: Vektek: Products: Hydraulic: Rotating Unions.

 

[gmwest80]

It would be safe to say that if the unit had true continuous rotation. I saw a tiny fabricated unit that could only do about 300ｰ, and it just had a little extra hose to allow that. If push came to shove, and you have a lathe, you could make a four-port rotary union, but I'd look for something like this first, if it wasn't too pricy: Vektek: Products: Hydraulic: Rotating Unions.

I really appreciate everyone who replied so for, nice to have a place to discuss ideas, I actually just source a dual port rotary today for about $500 buck, so I do believe I am getting there, baby steps and all.

 

[4570Man]

Have you priced the other parts? I had all the hydraulics from a scrapped skid steer when I was playing with the idea. Otherwise building one is an unattractive option.

 

[kthompson]

I worked for a company who made mobile hyd cranes and it may be the same by another name but we used "hydraulic swivel" is what we called them. Allowed continuous rotation. Many gallons of high pressure oil through them.

 

[gmwest80]

Have you priced the other parts? I had all the hydraulics from a scrapped skid steer when I was playing with the idea. Otherwise building one is an unattractive option.

so for I have priced the rotary unions in to $500 to $1000 range, and the swing motors are about the same range, joy sticks, around a grand also, seems like every component is around a grand:/ So it is pretty safe to say you will have 3 to 5 grand in the hydraulics alone, its a toss up, you might could shop around for something used, but I may have something to prove to myself that I can do it. Just not sure, it will of course most likely come back to money, that makes my decision, always does Thanks for replying sir

 

[4570Man]

That's before cylinders, hoses, pumps, track drive motors, and an engine

 

[DieselBound]

There's something to be said about economies of scale in manufacturing!