Why do most tractors with FEL's.........................

[Henro]

Hi,

I must admit that I went back and tried to read this thread a second time, in its entirety, as the conclusion reached at the end does not compute in my mind: I mean I don't know what the conclusion is !

The placement of a cylinder to give better routing of hoses is not where my confusion is. Neither is the consideration of having the rod seal on the bottom where dirt would fall off rather than accumulate.

Was the question related to cylinder extension and retraction forces settled?

It seems like there was denial that a cylinder could provide more force in one direction than the other. In the end was this "fact" accepted or not?

Granted a cylinder will extend regardless whether fluid is pumped in on the rod end of the piston, or the cylinder-bore side of the piston, if the other side of the cylinder is left open to atmosphere, or returned to tank. But the force generated by the cylinder will be greater if the fluid is pumped into the cylinder-bore side of the piston.

At the end of the day, was the conclusion that as long as the fluid is pumped into the cylinder bore side of the cylinder, the force generated will be the same (maximum for that cylinder) regardless of cylinder orientation? I think this must be it... Pumping fluid into the bore end of the cylinder would give maximum extension force, and maximum loader lift.

If this is the case then cylinder orientation would be chosen according to best hydraulic line routing and rod seal considerations.

Hope I hit the nail on the head!

Bill

 

[k0ua]

Hi,

I must admit that I went back and tried to read this thread a second time, in its entirety, as the conclusion reached at the end does not compute in my mind: I mean I don't know what the conclusion is !

The placement of a cylinder to give better routing of hoses is not where my confusion is. Neither is the consideration of having the rod seal on the bottom where dirt would fall off rather than accumulate.

Was the question related to cylinder extension and retraction forces settled?

It seems like there was denial that a cylinder could provide more force in one direction than the other. In the end was this "fact" accepted or not?

Granted a cylinder will extend regardless whether fluid is pumped in on the rod end of the piston, or the cylinder-bore side of the piston, if the other side of the cylinder is left open to atmosphere, or returned to tank. But the force generated by the cylinder will be greater if the fluid is pumped into the cylinder-bore side of the piston.

At the end of the day, was the conclusion that as long as the fluid is pumped into the cylinder bore side of the cylinder, the force generated will be the same (maximum for that cylinder) regardless of cylinder orientation? I think this must be it... Pumping fluid into the bore end of the cylinder would give maximum extension force, and maximum loader lift.

If this is the case then cylinder orientation would be chosen according to best hydraulic line routing and rod seal considerations.

Hope I hit the nail on the head!

Bill

Uh.. not exactly. The rod WILL NOT extend if the fluid is pumped into the rod side of the cylinder. It will retract. The rod will extend only if the fluid flow is directed to the cap side of the cylinder not the rod side. I am sure you did not intend to say this: "Granted a cylinder will extend regardless whether fluid is pumped in on the rod end of the piston, or the cylinder-bore side of the piston,"

You are correct that maximum extension force is achieved by directing the fluid flow on the cap side and maximum retraction force is achieved by directing fluid on the rod side. AND that the force exerted by directing the fluid flow on the cap side is larger than directing the fluid flow on the rod side because there is more square inches of piston for the fluid to push against on the cap side. BUT it is NOT true that applying fluid on either side will cause the rod to extend. It is also true that if the fluid flow is applied to both sides simultaneously that the rod will extend as the cap side force is greater than the rod side force. It is also finally been "put to bed" by all concerned that the orientation of the hydraulic cylinder does not change its extension power in any significant manner.

 

[SPYDERLK]

Hi,

I must admit that I went back and tried to read this thread a second time, in its entirety, as the conclusion reached at the end does not compute in my mind: I mean I don't know what the conclusion is !

The placement of a cylinder to give better routing of hoses is not where my confusion is. Neither is the consideration of having the rod seal on the bottom where dirt would fall off rather than accumulate.

Was the question related to cylinder extension and retraction forces settled?

It seems like there was denial that a cylinder could provide more force in one direction than the other. In the end was this "fact" accepted or not?

Granted a cylinder will extend regardless whether fluid is pumped in on the rod end of the piston, or the cylinder-bore side of the piston, if the other side of the cylinder is left open to atmosphere, or returned to tank. But the force generated by the cylinder will be greater if the fluid is pumped into the cylinder-bore side of the piston.

At the end of the day, was the conclusion that as long as the fluid is pumped into the cylinder bore side of the cylinder, the force generated will be the same (maximum for that cylinder) regardless of cylinder orientation? I think this must be it... Pumping fluid into the bore end of the cylinder would give maximum extension force, and maximum loader lift.

If this is the case then cylinder orientation would be chosen according to best hydraulic line routing and rod seal considerations.

Hope I hit the nail on the head!

Bill

There was never any contention that I saw that a cylinder being extended produces greater force. At least one person confused cyl extension with cyl orientation and persisted regardless of correct explanation. There was an eventual epiphany.

 

[SPYDERLK]

Hi,

I must admit that I went back and tried to read this thread a second time, in its entirety, as the conclusion reached at the end does not compute in my mind: I mean I don't know what the conclusion is !

The placement of a cylinder to give better routing of hoses is not where my confusion is. Neither is the consideration of having the rod seal on the bottom where dirt would fall off rather than accumulate.

Was the question related to cylinder extension and retraction forces settled?

It seems like there was denial that a cylinder could provide more force in one direction than the other. In the end was this "fact" accepted or not?

Granted a cylinder will extend regardless whether fluid is pumped in on the rod end of the piston, or the cylinder-bore side of the piston, if the other side of the cylinder is left open to atmosphere, or returned to tank. But the force generated by the cylinder will be greater if the fluid is pumped into the cylinder-bore side of the piston.

At the end of the day, was the conclusion that as long as the fluid is pumped into the cylinder bore side of the cylinder, the force generated will be the same (maximum for that cylinder) regardless of cylinder orientation? I think this must be it... Pumping fluid into the bore end of the cylinder would give maximum extension force, and maximum loader lift.

If this is the case then cylinder orientation would be chosen according to best hydraulic line routing and rod seal considerations.

Hope I hit the nail on the head!

Bill

Uh.. not exactly. The rod WILL NOT extend if the fluid is pumped into the rod side of the cylinder. It will retract. The rod will extend only if the fluid flow is directed to the cap side of the cylinder not the rod side. I am sure you did not intend to say this: "Granted a cylinder will extend regardless whether fluid is pumped in on the rod end of the piston, or the cylinder-bore side of the piston,"

You are correct that maximum extension force is achieved by directing the fluid flow on the cap side and maximum retraction force is achieved by directing fluid on the rod side. AND that the force exerted by directing the fluid flow on the cap side is larger than directing the fluid flow on the rod side because there is more square inches of piston for the fluid to push against on the cap side. BUT it is NOT true that applying fluid on either side will cause the rod to extend. It is also true that if the fluid flow is applied to both sides simultaneously that the rod will extend as the cap side force is greater than the rod side force. It is also finally been "put to bed" by all concerned that the orientation of the hydraulic cylinder does not change its extension power in any significant manner.

See highlighted wording. Unusual situation but correct. :confused3: Extend?/Move?

 

[tommu56]

I didn't read the whole thread or sleep at a Holiday Inn last night!

My take is the oil that leaks out seal and foreign matter that lands on rod tends to go down hill away from the seal not piling up on seal and working under it causing it to wear faster.

Same as inverted forks on motorcycles.

just my $0.02

Tom

 

[Grandad4]

If this is the case then cylinder orientation would be chosen according to best hydraulic line routing and rod seal considerations.

Well, I had another theory (or at least a question), post #62, but I guess it got lost in all the other excitement.

 

[Henro]

Well, I did indicate my head was spinning after trying to read through this thread twice! (embarrassed)

I was probably thinking move when I wrote extend. Without question fluid going into the rod side makes the cylinder shorter, and fluid going into the other end of the cylinder (call it bore side, or piston side)makes the cylinder overall length become longer.

And since the physical layout of the loader arms causes lift when the cylinder is extended, maximum lifting force is experienced when the cylinder is extended regardless of the physical orientation of the cylinder.

So the answer to the original question is that the position (orientation) of the cylinders has nothing to do with lift capacity and everything to do with hose placement and protection of the cylinder rod seal.

Got it! :thumbsup:

 

[lennyzx11]

After reading through this thread, I am working out in my head if the cylinder orientation could have a "different" rate of fall with gravity pushing(actually pulling) the bucket down. Related to the regeneration mode due to the rod surface area vs the flat piston side.

And I also am curious about the orientation affecting the strength needed to bend an inner rod.

 

[Creamer]

I am still convinced it has nothing to do with rod protection or gland seal protection. Rather hose routing.

If on an backhoe, if the barrel was pointing north and the rod south, everytime that function operated that barrel would extend away from where the rod is mounted, and thus the hoses and hydraulic lines would also have to move.

With the rod pointed north, the only movement of the barrel is basically rotation. So its easier to route the hoses.

Basically, the barrel is attached to whatever the hydraulic lines are.

Agreed!

I am still trying to figure out how the hose routing would be if the cylinders were mounted barrel down. The hoses would need to run under the tractor across the loader subframe and remain on the tractor when the loader was off? What a mess?

Much cleaner to have all the hoses mounted on the loader and all the connections in one area so you unhook the QDs and you are done. To have a quick Attach loader this is almost a necessity.

 

[the old grind]

About the motorcycle fork thing ... inverted forks are much stiffer o'all. This is important to reduce twisting forces/effects that on FELs etc are absorbed/controlled by loader arm rigidity (vs triple trees) that few bikes have similar to. (btw, remember tweek bars? )

That bent rod in the pic above ... it takes a lot of o'load to start such a bend, progressively less as you go from there. Looks like whatever load bent it just ran out of travel at that degree of 'oh s__'.