Long-Stroke Rodless Hydraulic Cylinder
Long-Stroke Rodless Hydraulic Cylinder
(OP)
Hello All,
I'm looking to replace vertical lift of ours that utilizes a chain-over-roller hydraulic cylinder, with a 93" stroke that carries a drum (and conveyor) up about 163". I would like to use our current hydraulic system (for various reasons) so I am considering moving to a rodless cylinder. I haven't had much success locating a manufacturer of rodless hydraulic cylinders with this stroke (let alone specifying bore, load capacities, etc. yet). Does anyone know if someone makes something like this? I can quickly tell it's not an industry standard. I'm also open to other ideas. Electric is possible but would require a complete overhaul of the system the lift is apart of (changing obsolete PLC, drives, motors, etc.). This should all be done anyway but isn't something we can necessarily tackle right now.
I'm looking to replace vertical lift of ours that utilizes a chain-over-roller hydraulic cylinder, with a 93" stroke that carries a drum (and conveyor) up about 163". I would like to use our current hydraulic system (for various reasons) so I am considering moving to a rodless cylinder. I haven't had much success locating a manufacturer of rodless hydraulic cylinders with this stroke (let alone specifying bore, load capacities, etc. yet). Does anyone know if someone makes something like this? I can quickly tell it's not an industry standard. I'm also open to other ideas. Electric is possible but would require a complete overhaul of the system the lift is apart of (changing obsolete PLC, drives, motors, etc.). This should all be done anyway but isn't something we can necessarily tackle right now.
RE: Long-Stroke Rodless Hydraulic Cylinder
Ted
RE: Long-Stroke Rodless Hydraulic Cylinder
RE: Long-Stroke Rodless Hydraulic Cylinder
If there's a static load/torque on it, and you want it to maintain position indefinitely, you'll need shear-seal or soft-seat blocking valves to prevent rotation of the output shaft, or a friction brake to immobilize it mechanically. The right servovalve will hold position for as long as the power is on.
The cheapest way to get vertical linear motion from a hydraulic motor is sprockets on a horizontal shaft, and roller chain.
You don't need a brake to hold position if you use a leadscrew with a fine-ish pitch.
Mike Halloran
Pembroke Pines, FL, USA
RE: Long-Stroke Rodless Hydraulic Cylinder
Ted
RE: Long-Stroke Rodless Hydraulic Cylinder
My specific loading requirements would probably require either more than one or an extended trolley, both of which their engineer said could be done. I would think the latter so that I'm not worrying about delivering the same flow to each. Anyone have any thoughts or experience with these? I've only used their smaller, pneumatic versions in horizontal applications. I'm not sure what kind of drift performance they have or longevity.
RE: Long-Stroke Rodless Hydraulic Cylinder
Mike Halloran
Pembroke Pines, FL, USA
RE: Long-Stroke Rodless Hydraulic Cylinder
Drift depends on reliability of the piston seal as well as valves.
Hydraulic motor, worm drive, roller chain, done.
Ted
RE: Long-Stroke Rodless Hydraulic Cylinder
RE: Long-Stroke Rodless Hydraulic Cylinder
Maybe a chain loop. Maybe a pull-pull chain somewhat like a rack and pinion. Double sprocket pull-pull. Just imagination and creativity to do what you want to do.
Ted
RE: Long-Stroke Rodless Hydraulic Cylinder
RE: Long-Stroke Rodless Hydraulic Cylinder
Due to I.P. restrictions I can't show a picture of the set-up in the field, but it's using a Langely EH-102 Stationary Powerlift. Link
There is a single hydraulic cylinder that lifts a plate with two sprockets on either side, which chains wrap around and down to the carriage that is raised. This configuration doubles the displacement of the carriage with respect to the actuation of the cylinder.
The current load is about 300 lbs. (conveyor + drum), with the C.O.G. about 10" offset from the axis of the cylinder and elevator frame that the carriage's rollers ride in.
RE: Long-Stroke Rodless Hydraulic Cylinder
Ted