torch
Well-known member
Equipment
B7100HSD, B2789, B2550, B4672, 48" cultivator, homemade FEL and Cab
Well he does call it a "bidirectional cylinder". But when he says "manual pump" I'm not so sure it's double acting. And i am curious what size cylinder it takes to lift a 400 lb load on the end of a 26' long lever that weighs another 1,700 lbs.I seriously doubt thats going to be a problem. When extending a DA cylinder all you lose is the volume of the rod. My little B7200 has no problems with my 4 x 24 log splitter cylinder. The 1.5" rod displaces 42 cubic inches = .75 quarts.
Dan
Is there a hose to each end of the cylinder?
Let us suppose that the pump delivers 0.3 cu. in. per stroke. And let us suppose that the operator can pump it 30 strokes per minute. Over 45 minutes, that would be about 6-1/2 litres of fluid. Definitely more than should be drawn out of the tractor.
That would be consistent with a 20" stroke length in a 5" cylinder. A 2" diameter rod could be expected in that size, so even a double acting cylinder would drop the reservoir 2 litres. Well below the add mark on the dipstick.
Of course, I'm making a lot of suppositions here. Maybe the 45 minute estimate is based on 10 or 15 strokes per minute, or maybe the pump only delivers 0.05 or 0.1 cu. in. per stroke. And the angle will make a big difference -- even a 1-1/2" cylinder could lift that weight IF it starts off pushing straight up. As the tower tilts towards vertical, the downward force would be reduced. Possibly at the same rate the cylinder lifting force is reduced as it tilts towards the base.
That's why it would be nice to have real data.
The other issue that comes to mind is pressure. A quick look at Enerpac's website suggests their manual pumps can deliver anywhere from 5,000 to 10,000 psi. So the existing cylinder may not be big enough to lift the load when powered from a 1,700 psi tractor hydraulic pump.