oxidation problems inside single-acting cylinders

[Messerschmitt]

I would like to expose a problem, with regard to single-acting cylinders with stem-side oil input.
more or less this is the problem: the cylinder is hung vertically, with the stem facing down and a weight attached to the stem. sending oil on the stem side, this falls back and raises the weight. instead the descent must take place quickly by gravity, putting to drain the stem side.
the position in which the cylinder is found for the most part of the time is the one with back stem and therefore with the raised weight.
to simplify the circuit, I thought to keep the room side dry and in communication with the atmosphere. in this way to bring down this weight I just need to unload the stem side, and the descent is not slowed by the fact that the cylinder must suck oil on the backside, with probable cavitation problems (the control unit is far and lower than the cylinder)
therefore remains the problem of caution against the accidental input of water or condensation inside the cylinder side back, which could give oxidation. for the truth the stem, for most of the time, is found returned inside the cylinder, so there would be no oxidation problems where the plunger flows, but I think it would be better to avoid just any oxidation.

what solutions could I take to not have water on the backside?

 

[Lollos]

Good morning
normally to remedy this problem, it is used to connect the utilities of the cylinders that are not fed, to the highest part of the oil tank, so that the cylinder chambers remain oil free and therefore there are no cavitation problems, but at the same time there are no problems or contamination from external elements, or oxidation.
in practice is the solution adopted on cylinders with simple effect of forklifts.
I hope the solution is satisfactory to your needs.
greetings

 

[Messerschmitt]

Thanks for the answer.
Your solution seems good to me, but someone told me that inside the tanks of the hydraulic power stations there can be the formation of condensation, and therefore there is the risk of bringing water inside the cylinder.
However, considering the other alternatives, yours seems to me the best.
Could it have any usefulness to put a little hydraulic oil on the sheath side anyway, so that it performs a protective function?

 

[Lollos]

Good morning
I confirm what they told you, in the oil tanks it always forms condensation, unless they are pressurized as in hydrostatic plants, but the thing is negligible compared to the advantage it derives.
As for the insertion of oil in the sheath side is undoubtedly a good idea against oxidation as it always keeps a protective film on the cylinder walls, although it is necessary to consider that when the piston is all closed, oil in the compartment remains very little, but everything helps to improve working conditions.
cordial greetings

 

[Messerschmitt]

Okay, I'll do this. I think that's what's less troublesome.

 

[athlon]

You can set up remote controlled beams directly on the cylinder, when you want to get rid of the beams between the stem and the melt side and the oil goes from the stem side to the melted side

when instead salt the oil of the side melt returns in the tank (the pipe is down and the oil is pushed) side stem instead comes oil in pressure that moves the piston.

so you have only 2 tubes going to the piston and a simple electric cable

 

[Vash]

Hello, everyone.

First of all I can say that I am the owner of a company that builds hydraulic cylinders of many types and sizes.

but reconnecting me to the discussion, there are two possible choices remaining in a "simple" field without making too many "casini".

first choice
connects a tube to the side of the cylinder that is not fed with the pressure of the plant and connects it to a small tank separately, or to the general tank, but taking into consideration to insert it so that it can "weight" clean oil and not bottom tank or only air. the operation is this, closed cylinder, pressure to the backside, cylinder out, pressure elimination then the cylinder drops for weight or other, while the same goes down or however closes, you go to create an aspiration on the "free" side that goes to suck oil from the tank; at this point when the cylinder will extend again, will release the oil by sending it to the tank separately or general.

second choice
the seal is eliminated on the inner component and therefore the cylinder is transformed from simple effect to dive.it is necessary however to consider two things, the first is that the thrust surface will no longer be given by the area of the inner diameter of the tube but rather by the area of the diameter of the stem; the second is that the driving head must necessarily have a seal of seal, (balance, tti, sm, ch, etc...)


I hope I was useful for the discussion.:biggrin:

hello to all:finger:

 

[Focus]

Hello, everyone.

....

second choice
the seal is eliminated on the inner component and therefore the cylinder is transformed from simple effect to dive.it is necessary however to consider two things, the first is that the thrust surface will no longer be given by the area of the inner diameter of the tube but rather by the area of the diameter of the stem; the second is that the driving head must necessarily have a seal of seal, (balance, tti, sm, ch, etc...)


I hope I was useful for the discussion.:biggrin:

hello to all:finger:

a single-effect traction plunger? :finger:

Hi.

 

[Vash]

Hi.

if we consider a simple traction effect, of course you can use
only the first choice because turning it into "tuffante" the cylinder, clearly, would not work in traction.



Hi...:biggrin:

 

[Messerschmitt]

I was late to notice that there were other answers to my question.
What do you mean? by now the cylinder has been in the house for a few weeks, just wait to be installed. the solution that I adopted is that of the sheath side that aspires air, and I will put some silicone fat inside the room so as to minimize any problems of oxidation. However, consider that the cylinder is always in the back position, so the sliding part is always protected.