Precise flow divider for 700 bar pressure
Precise flow divider for 700 bar pressure
(OP)
Hello,
can anybody give me an advice where to look for a gear type flow divider (or maybe another design type) for a system that has a maximum operating pressure of a 700 bars (~ 10152 psi).
I have looked but have not been successful, every option I found max out at around 350 bars.
I need a device to equally distribute flow to let's say 4 hydraulic cylinders, at 700 bars of pressure. Voulume (flow) is not so relevant, it is very low).
I found just this kind of system (not sure if I am alloved to put links in thread) :
https://www.lemacher-hydraulik.de/en/products/line...
Thank you for help.
can anybody give me an advice where to look for a gear type flow divider (or maybe another design type) for a system that has a maximum operating pressure of a 700 bars (~ 10152 psi).
I have looked but have not been successful, every option I found max out at around 350 bars.
I need a device to equally distribute flow to let's say 4 hydraulic cylinders, at 700 bars of pressure. Voulume (flow) is not so relevant, it is very low).
I found just this kind of system (not sure if I am alloved to put links in thread) :
https://www.lemacher-hydraulik.de/en/products/line...
Thank you for help.
RE: Precise flow divider for 700 bar pressure
Ted
RE: Precise flow divider for 700 bar pressure
RE: Precise flow divider for 700 bar pressure
For example: https://royalhydraulics.com/index.php/45-products/...
Ted
RE: Precise flow divider for 700 bar pressure
Simple but should work..
https://www.jotek.se/product/fordelningsblock-4-va...
Best regards A
“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
RE: Precise flow divider for 700 bar pressure
And a purely mechanical option is what they use to lift buildings. I have never seen a detailed drawing but from what I understand it is a large area piston driving many smaller pistons. You have to have equal flow even if the smaller cylinders have unequal pressure.
RE: Precise flow divider for 700 bar pressure
2IceStationZebra - That's what I do need, a divider that will send equal flow regardless of counter-force being applied on cylinder rod.
RE: Precise flow divider for 700 bar pressure
And why the pressure must be 700 bar?
Best Regards A
“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
RE: Precise flow divider for 700 bar pressure
I once consulted on a dam project. Each end of the dam gate was lifted by a pump. The gates were long and about 100 tons. There were crude position sensors. Should one end of the gate be higher than the other by some amount then some of the oil from the high cylinder was dumped to tank till it was even with the lower cylinder. Simple.
The question I have is why not make the cylinder areas twice as big so a more reasonable 350 bar can be used.
Then the flow dividers wouldn't be needed. Still use the simple technique of relieving oil from any cylinder that is too high.
Peter Nachtwey
Delta Computer Systems
http://www.deltamotion.com
http://forum.deltamotion.com/
IFPE Hall of Fame Member
RE: Precise flow divider for 700 bar pressure
The reason why there are so few hydraulic components with higher pressures than 350 - 420 bar ..
Is that cost end the risk assessment increases exponentially with the pressure increase.
So it is better to stick to "as low" pressures as possible as long as the force can be maintained.
The risk assessment for the force you need to do anyway..
But it is difficult to give good edvice, when one does not know the end purpose/functionality ..
Best regards A
“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
RE: Precise flow divider for 700 bar pressure
I have a question about nozzels to reduce the hydraulic flow, is that something you can help me with?
Do not really know in which forum I should put the question
Best Regards A
“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
RE: Precise flow divider for 700 bar pressure
RE: Precise flow divider for 700 bar pressure
Or do you need the posibility ta adjust the cylinders into diffrent hights?
BR A
“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
RE: Precise flow divider for 700 bar pressure
Use the trick I mention about relieving some oil on any cylinder that is higher than the others. It has worked for dams.
Feedback will be required.
The Emsworth dams below Pittsburgh work this way.
Ditto Redsnakes' concerns about the higher pressure when the diameter of the cylinder only increase roughly by 1.41 times.
@Redsnake, you should start a new thread rather than distracting this one.
Peter Nachtwey
Delta Computer Systems
http://www.deltamotion.com
http://forum.deltamotion.com/
IFPE Hall of Fame Member
RE: Precise flow divider for 700 bar pressure
This is not perfect but it will give us some control. Simplicity and cost effectivness the goal.
RE: Precise flow divider for 700 bar pressure
If you meen the nozzle problem, I did.
BR A
“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
RE: Precise flow divider for 700 bar pressure
RE: Precise flow divider for 700 bar pressure
When multiple cylinders are being used to raise a load, I've found only two approaches that work:
(1) Make the mechanism linking the cylinders sufficiently rigid so that a lagging cylinder will be dragged along without jamming.
(2) Make the mechanism so flexible that any one cylinder can deflect to full stroke without depending on the others moving at all.
In-between is asking for trouble.
In the case of, for example, raising a platform, (1) could include: A structure sufficiently rigid that it can't jam against its guides, e.g. the "platform" is shaped like a cube as opposed to a piece of paper, (2) a rack-and-pinion mechanism at each corner with the pinions connected by shafts, (3) a ball-screw or similar device at each corner linked by timing-belt or sprocket-and-chain drives, etc.
RE: Precise flow divider for 700 bar pressure
Okey, like a car bridge _/ \_ or _/ or ↑-↑ or do you mean something that is used to raise a bridge under construction ?
Best regards A
“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
RE: Precise flow divider for 700 bar pressure
Ted
RE: Precise flow divider for 700 bar pressure
A gear type flow divider is rated for low pressure because of the bearing loads and contamination caused by the high pressure acting on one side of the gear.
A sufficiently high pressure will cause the gear to deflect and run against the metal of the housing, which in turn will cause the internals of the housing to be damaged.
That will introduce contamination in the system and probably cause failures in other components.
Any type of bearing (Journal or Ball) will not be happy with the deflection either, which in turn will wear out the bearings very quickly and generate more contamination.
All that is to say that I do not think that you will find any gear type flow divider with a 700 BAR pressure rating.
Not to mention the potential lockup issues and other application details, like partially independent control, that may mess with the flow divider function.
700 BAR is a high pressure.
If you still want to use a gear type flow divider I would, as others have suggested, try to reduce the pressure by increasing the area of your cylinders.
If you have small cylinders, then this probably would not increase their diameter much (1" to 1.5" bore cylinder area ratio is 2.25, which is sufficient to bring the final required pressure to under 350 BAR, assuming you are using the blind end of the cylinders for the 700 BAR load).
If you want the cylinders to move together, but also be independently controllable, then the easiest way to do so (at 700 BAR) is with electronically controlled valves, a programmed controller, and some position feedback sensors.
It is possible to do so with hydraulically piloted valves, but it will not be as compact, flexible, or accurate as an electronically controlled valve w/ a controller.