hydraulic felling wedge.

[Mr Ed]

I wonder if one could be made to work off a tractors hydraulics that would be handy?

 

Not enough pressure. You need about 10,000 psi...

[Steve Bullman]

well ive not much idea about hydraulics to be honest, but would the pressure be lost over such lengths?

[David oakman]

Most prob, you can see there is nothing on the tv i have been on here all night wife is now moaning:001_smile:

[Jamie]

see when you are bored, think THEN type.....i'm guilty of that too however

 

Jamie

[treequip]

Not enough pressure. You need about 10,000 psi...

 

The force a ram exerts is a function of the pressure and the dimensions of the bore. The compact rams you were using (Enerpac?) do operate at higher pressures but you can get 20 tons of force out of a regular ram.

Most tractors make about 2200 psi, the only problem is that you would need a feed and return (Siamese) hose which is going to be cumbersome and heavy (full of oil) at any sort of length. Pressure drop would not be a significant issue.

There are air operated hydraulic jacks that would only need an air feed, which is available on most commercial vehicles.

[Mr Ed]

The force a ram exerts is a function of the pressure and the dimensions of the bore..

 

Ever see the pump components on one of those hand operated portapacks? the pump section is about 3/8ths of an inch and an inch of stroke. Very low flow but very high pressures. Same as you see on hand operated hose swagers.

No need for two line hydraulics, as the rams are one way with sprung return. just open a valve and let the fluid return.

[treequip]

Ever see the pump components on one of those hand operated portapacks? the pump section is about 3/8ths of an inch and an inch of stroke. Very low flow but very high pressures. Same as you see on hand operated hose swagers.

No need for two line hydraulics, as the rams are one way with sprung return. just open a valve and let the fluid return.

 

That’s going to be a hell of a spring to push fluid back down 60 feet of hose. Better to use an air operated jack even if you have to run in from a weedy 12 volt tyre inflator. It would be slow but it would get you there.

[Mr Ed]

That’s going to be a hell of a spring to push fluid back down 60 feet of hose. Better to use an air operated jack even if you have to run in from a weedy 12 volt tyre inflator. It would be slow but it would get you there.

 

60ft?!? why so much hose? we used the same as the silvey, about 6 ft

why do you want to use an air operated jack? The standard manual pack works fine, bit hard to drag a compressor into the depths of the woods:confused1:

[treequip]

60ft?!? why so much hose? we used the same as the silvey, about 6 ft

why do you want to use an air operated jack? The standard manual pack works fine, bit hard to drag a compressor into the depths of the woods:confused1:

 

Its the specification I was given and we dont all work in the depths of the woods.

 

I was thinking of 60 feet of hydraulic hose maybe 100 to play safe:001_smile:

[Mr Ed]

Ah. well the tractor hydraulics option is never going to work, as the pump will not make the pressure.

As for having to use a tractor just to power a felling wedge....

 

The air jack idea is a good one though, if you did a little re-engineering on the jack.

 

The thing about the proper Silvey jacks is that they are light (made from Aloominum) and very powerfull - 45 tonnes from a tiny jack...