Hold Me, Squeeze Me…Which, Or Both?

[Henro]

Steve,

They way you have drawn it is the way I see it.

In a perfect world there would be no pressure at point "AA" that is true.

However, in the "real" world, there is resistance to flow encountered even in a straight pipe. Such resistance to flow in a circuit like in a tractor's open center loop, will without question result in back pressure in the loop that the fluid flows through. This pressure would be max at closest to the pump, and zero at the hydraulic tank.

The fact that we live in the real world is why the CC valve that shunts (parallels) can actually supply some pressure to work a cylinder. The question is not whether there is pressure at point AA, but rather how much. JerryG in another thread has reported seeing system pressures of about 100 to 200 psi with nothing operating. I don't think anyone else has reported an actual measurement. My gut says Jerryg's report is reasonable. I wish I had a means at hand to make a measurement myself.

No doubt in my mind that this is truly the way things are... /forums/images/graemlins/smile.gif

Actually, now that I see how things are working, I think this is a pretty clever application of a closed circuit valve. /forums/images/graemlins/smile.gif

When one of the OC valves that are in the circuit are operated, the pressure at point AA will rise, up to the pressure at which the system PRV pops if that point is reached, like when a loader treaches limit of travel, for example.

Hope this makes sense to someone other than me! /forums/images/graemlins/crazy.gif

 

[BigAl]

OK you guys! "I give up" ! I come to TBN to read great tips, good information and have a relaxing good time and now I have this huge HEADACHE from trying to understand all this with my little pee brain /forums/images/graemlins/mad.gif.
HENRO!!! , You need a job ! You have entirely too much time on your hands to think up all this stuff .
I going to go now ,to the bathroom , but now I think , maybe I might need someone to hold my hand ! Geez! I'm just not sure anymore. /forums/images/graemlins/crazy.gif
Big Al

 

[BarryinMN]

Here's a grapple working. This is the stuff too big to bush hog down. I run it from a rear remote that has a float position.

 

[WhiteRock]

Actually given that this already works well, if you were to need a tighter squeeze , just hold the CC valve in the close position, raise the 3pt hitch load to get a tighter grapple grip, release both the CC valve and the 3pt hitch. Kinda like a turbo button!

This is just a variation of what Henro said, but you wouldn't have to move your bucket... pretty clever I think! /forums/images/graemlins/cool.gif /forums/images/graemlins/smile.gif /forums/images/graemlins/grin.gif

 

[ronjhall]

Al
I see where you are confused. /forums/images/graemlins/confused.gif
It's your spelling and interpretation of that spelling.
<font color="blue"> pee brain </font> /forums/images/graemlins/frown.gif
Should have been Pea Brain. /forums/images/graemlins/blush.gif /forums/images/graemlins/grin.gif
But then maybe I'm confused. /forums/images/graemlins/confused.gif
Trying to interpret someone elses post. /forums/images/graemlins/crazy.gif /forums/images/graemlins/grin.gif
I should stick to pictures. /forums/images/graemlins/smile.gif

 

[ronjhall]

I took some picture while using my Grapple to move remains of 8 trees that I cut down. Here is a link to them. Click Here.
Did not have the Toothbar on. It helps picking up logs because it extends the front edge of the bucket.
Hauled the branches about 500 ft to where I'm going to chip them up.

 

[PineRidge]

Ron that's a great series of pictures. I especially like the snow plow! /forums/images/graemlins/grin.gif

 

[ronjhall]

Thanks Mike
Got up this morning with News reports saying 4" of snow. Did my TBN thing then decided to go out and get paper.
Snow was over my boots. Plugged in the <font color="orange"> Kubota </font> and <font color="green"> JD </font>block heaters. After a hour started up the <font color="orange"> Kubota </font>. Switched grapple bucket for snow blade. Just got back in after 3 hours plus plowing, snow blowing and digging out neighbors van. Found a new use for a snowblower. It sure is a great tool for clearing out the snow bank neighbor had backed their van into. /forums/images/graemlins/grin.gif