pneumatic electro drilling unit

[exxon]

a solution that takes inspiration from the idea of the oversized wttm cylinder, is that of control through a differential pressure.

I press that it is not the optimal solution, because the position control in a drilling must be accurate and can not be left to the action of a pneumatic cylinder, but it is interesting because it minimizes the leap forward and could return useful in other applications.

the complete pneumatic scheme and the one in the figure to follow.
what pushes the piston is the difference in pressure δp while the volume reduction and consequently the leap forward is proportional to δp/pm e non a δp/p as in case the room downstream discharged into the atmosphere.

 

[welcome to the machine]

exxon you write too fast and I don't make time to write two bullshit that you've already written a treaty... so it's not worth!
Anyway I have written and published the post without reading your...
I try to reformulate:
1) Upper end piston: back room pressure room, front room-side stem- pressure supply
2) the control valve switches and feeds the back chamber while it stops feeding that stem side: lacking the pressure, the unidirectional valve blocks the air still under pressure in the room side of the stem, unless the very short trafilage that occurs in the switching, in fact, of the unidirectional valley itself.
3) At this point the stele side chamber can download its pressure only through the flow regulator bottle. at equal supply pressure upstream of the control valve, the air begins to enter the back chamber and the piston will begin to move in operation - neglecting the frictions- of the difference of force that insists between the two surfaces, due to the pressure and the surface itself. the back chamber is fed by the source while that side stems, if the speed you try to get is low and the stroke is short, it will tend to lose pressure to the air flow outwards, through the stroking.
the problem is that the room side stem loses pressure even regardless of the piston push, so the adjustment effect lasts little time. for this I speak of cylinders larger than necessary only for the purpose of the push: contain a greater air volume and the braking effect of forced output lasts a little more. Also the variation of resistance at the time of breakup is less significant and influences in a reduced way the control of movement.

 

[welcome to the machine]

rest of the notice that the regulator symbol you use is not the correct one. the arrow indicates the sense of regulation, and it is the same in which the sphere of the universal block the flow in by pass (otherwise the air passes from there and cares about the stroking). Perhaps it is a detail, but it does not allow it to follow the logic of your scheme well and its explanation.

 

[exxon]

rest of the notice that the regulator symbol you use is not the correct one. the arrow indicates the sense of regulation, and it is the same in which the sphere of the universal block the flow in by pass (otherwise the air passes from there and cares about the stroking). Perhaps it is a detail, but it does not allow it to follow the logic of your scheme well and its explanation.

I don't think the adjustment arrow has anything to do with the flow direction of the fluid. Flow regulators are pin valves that for this function are perfectly bidirectional. what makes the difference is the unidirectional valve in parallel whose symbol indicates the bypass direction. to me it seems to have drawn it correctly (I put a particular).

 

[exxon]

the problem is that the room side stem loses pressure even regardless of the piston push, so the adjustment effect lasts little time. for this I speak of cylinders larger than necessary only for the purpose of the push: contain a greater air volume and the braking effect of forced output lasts a little more. Also the variation of resistance at the time of breakup is less significant and influences in a reduced way the control of movement.

Now I understand what you meant with oversized cylinder. I imagined a large section cylinder to push it with a small differential pressure.

I do not think that the choice of delaying the emptying of the valley room is feasible: to achieve result, the speed of emptying should be identical to that of the advancement of the stem; The latter, however, is determined by the advancement of the tip in the piece and is not determinable a priori depending on many factors, such as the state of the cutting edges. in case of different speeds we would have or the speed of advancement of the tip determined by the flow regulator valve (not a reliable regulation), or early emptying resulting in forward jump of the stem.

Now I make some accounts to see how large the scissors of possible error are.

 

[welcome to the machine]

"I imagined a large section cylinder to push it with a small differential pressure" this is the primary reason. the longer duration of the adjustment effect due to the strozer is only a side factor, but it helps little. "I don't think the choice to delay the emptying of the downstream chamber is feasible"In fact I don't think so either, too many factors regulate the need to have a speed of advancement rather than another one and you can't think of ... hurry to drill otherwise you empty the room.

 

[welcome to the machine]

You're right about the symbol: I have looked at catalogues and had the regulator arrow in the same direction as the flow regulation is only, probably, a case. There's both one guy and the other.

 

[exxon]

"... and you can't think of ... hurry to pierce otherwise you empty the room.

ohhhh, this is the right approach to design: evaluate All conditions with their implications. a little different from doing "patchwork" of standard notionism.

 

[stevie]

I wonder what the poor Darius could understand from this quarrel and confused discussion. .

 

[welcome to the machine]

if dario wants to buy a drilling unit already made, it has many possibilities, easily available on the catalogs on the net. pneumatic drives with hydraulically controlled feed speed are quite common and do not cost much. electronic control systems are increasingly widespread, since electronics costs less every day, and also on the net will find many. I have not yet understood if you can make here the names of the producing companies and I ask a moderator if it is correct or not, but I am sure that dario manages alone to find them.
If you want to draw it and realize it ad hoc, I think that the indications that emerged in this discussion can help him. He will inevitably find some discordant opinions, but I don't think he wants to give up his judgment entirely: you read the various posts, compare them with what you already know and will come to your conclusions. It seems like a normal process
that then the discussion was a little too quarrelsome is undeniable.

 

[cacciatorino]

. I have not yet understood if you can make here the names of the producing companies and I ask a moderator if it is correct or not, but I am sure that dario manages alone to find them.
.

as well as permission is very welcome.

 

[welcome to the machine]

Okay, hunter, thank you.
bones pneumatik makes many types and is in lombardy. Maybe dario can ask for their notice.

 

[exxon]

I wonder what the poor Darius could understand from this quarrel and confused discussion. .

Maybe the first solution wasn't good at all?
already this would save him some money and time.

pneumatic bonesi

would be the oleo-pneumatic cylinders you mentioned?
I never used them and I'm a little curious.

 

[welcome to the machine]

Yeah, exxon, I'm sorry I was watching a movie, and I realized I've only seen it in the end.

 

[stevie]

I doubt it, because on such a short run the possibility of adjusting speed by means of a flow strozer on the output is not so accurate. the drilling speed will determine the progress speed of the slide until the tip unleashed the residual part of the wall and the propeller of the tip will drag forward the slide. Perhaps you can try with a cylinder largely oversized compared to the only forces required to move the sled to a vacuum, so as to make less significant the load variations between drilling and "breaking" compared to the force applied by the cylinder itself. the units to perform these holes are, that I know, pneumo-hydraulic, with the control of the speed entrusted to a passive oil cylinder in parallel to the pneumatic cylinder.

that is exactly what he was talking about mechanicalmg when he was talking about ace dampeners.
to use an adjustable hydraulic brake is a good thing because the adjustment of the feed speed is much more effective than the only pneumatic flow regulator to the exhaust and also the minimum adjustable is much lower thanks to the incomprimibility of the oil (you do not have the typical stick-slip of the tire cylinders to the minimum).
But by reading what you write, a question arises, "but have you ever seen a drill pierce something? "
because here it seems that drilling an aluminum tube is a titanic enterprise.. .point warnings on the piece, need for differential pressure controls, adjustment of the output feed speed .
I am sure that a simple cylinder with chokers, having to pierce aluminum and not particularly ostic materials, is very suitable, as confirmed (I am the link since you can do, premitting that I have no relationship with the society indicated):
http://catalogo.ober.it/ober_catalogo3.asp?language=ita&gm=3&f=16&c=32 This society does exactly what has been said here... Unit ufm.
I don't think it's too much, there's exactly everything you need to do small holes, nothing more, nothing less.

to the worst, to avoid using an expensive hydraulic brake, I would put an adjustable spring match in the drilling run.

last detail. ..the tip should not be a common helical tip, but a step tip for sheet metal.

 

[welcome to the machine]

dear stevie
I want to tell you that not only did I see it, but I also did it personally and if you try to drill an aluminum tube by preventing the piece from turning without holding it vertically, let me know if the tip pulls it up or not.
in general I recommend to all those who write something in this community to avoid criticizing arrogantly and supposedly (can you write?) what others write.
It is still acceptable to stand alone, but to affirm that others have no idea what they are saying to me is excessive.
I think this is the dynamic of many chats, but I was hoping to find here a great majority of professionals who respect each other and, if necessary, criticize themselves correctly.
I come out of this discussion because I would be disappointed if I could point out that you are not among this majority. I hope not.

 

[exxon]

drilling a thin wall without control of relative position between piece and tip (maybe even by hand, but there must be) is guarantee not only of a job done wrong, but a great example of what not to do from the safety point of view.

in some companies (use), drilling a panel on column drill without blocked piece is right cause for dismissal. will there be a because, or are they also charlaters like those who are advising a different road in this thread?

then, that a tube can be drilled even with a screwdriver and its hammer is obvious, but everything can be done good or bad, it is to those who do the job to choose which professional want to be.

in technical detail an ace dampener serves nothing: one should not dissipate kinetic energy of a moving mass; It is necessary to maintain constant speed at the end of a load. the only mechanical system that guarantees this function is the hydraulic cylinder (or oleo-pneumatic, as suggested by wttm). as already discussed above, the most economical and functional system today, is however the electromechanical one.

so much to add some wood to the fire, you could object that the use of a tip to steps combined with a pneumatic system is certainly not a good choice, since it adds to every step a further leap forward of the tool that loses repeatedly resistance and is still pushed by the force of advancement without position control. the use of this tool on a curved surface is another force of its natural use.

wishing to discuss the type of tool, the one to use would instead be a "short" tip with angle of 90°, suitable to start the hole without preforum with tip from center. A guide compass is obviously indispensable at the entrance, while the one at the exit could be completely absent if the position control of the tool was electromechanical.

I conclude by saying that if wttm comes out of this discussion, who puts us back is the op and would be a sin. Instead, I avoid comments on certain obvious features to the eye even distracted.

 

[TECNOMODEL]

drilling a thin wall without control of relative position between piece and tip (maybe even by hand, but there must be) is guarantee not only of a job done wrong, but a great example of what not to do from the safety point of view.

in some companies (use), drill a panel on column drill without locked piece is just cause for dismissal. will there be a because, or are they also charlaters like those who are advising a different road in this thread?

then, that a tube can be drilled even with a screwdriver and its hammer is obvious, but everything can be done good or bad, it is to those who do the job to choose which professional want to be.

in technical detail an ace dampener serves nothing: one should not dissipate kinetic energy of a moving mass; It is necessary to maintain constant speed at the end of a load. the only mechanical system that guarantees this function is the hydraulic cylinder (or oleo-pneumatic, as suggested by wttm). as already discussed above, the most economical and functional system today, is however the electromechanical one.

so much to add some wood to the fire, you could object that the use of a tip to steps combined with a pneumatic system is certainly not a good choice, since it adds to every step a further leap forward of the tool that loses repeatedly resistance and is still pushed by the force of advancement without position control. the use of this tool on a curved surface is another force of its natural use.

wishing to discuss the type of tool, the one to use would instead be a "short" tip with angle of 90°, suitable to start the hole without preforum with tip from center. A guide compass is obviously indispensable at the entrance, while the one at the exit could be completely absent if the position control of the tool was electromechanical.

I conclude by saying that if wttm comes out of this discussion, who puts us back is the op and would be a sin. Instead, I avoid comments on certain obvious features to the eye even distracted.

I must be lost something, in which post someone recommends to pierce without blocking the piece?
If you need to smoke, as you often do, to move attention....
and, however, avoids giving some fabulous to others, and overflights on that "citizens" that, aimed at professionals with years of experience, I find really out of place.

 

[cacciatorino]

dear stevie
I want to tell you that not only did I see it, but I also did it personally and if you try to drill an aluminum tube by preventing the piece from turning without holding it vertically, let me know if the tip pulls it up or not.
in general I recommend to all those who write something in this community to avoid criticizing arrogantly and supposedly (can you write?) what others write.
It is still acceptable to stand alone, but to affirm that others have no idea what they are saying to me is excessive.
I think this is the dynamic of many chats, but I was hoping to find here a great majority of professionals who respect each other and, if necessary, criticize themselves correctly.
I come out of this discussion because I would be disappointed if I could point out that you are not among this majority. I hope not.

I do not see any arrogance in the words of stevie, only a call to greater realism. If we read certain posts I think that column drills should already have been abandoned in the early '900, instead we know well that you can use to make decent holes.

 

[stevie]

I must be lost something, in which post someone recommends to pierce without blocking the piece?
If you need to smoke, as you often do, to move attention....
and, however, avoids giving some fabulous to others, and overflights on that "citizens" that, aimed at professionals with years of experience, I find really out of place.

ah where I read that you want to drill a piece without bracket knows only him.. .

Besides speaking with one who has 30 years experience in mechanical processing, I the holes on hand drill did them to 14 years...I still have all my hands!!!
that there is a slight "contraccolpo" at the exit stage I understood it as a child. . .
Today I run a company with 4 turning centers, 4 working centers, 2 5-axis centers, column drills, tangential adjustments, circulars... maybe a few jobs I understand, don't I?

in addition to confirmation of the chestnuts that tells I have reported the site of a company (a spa, not of a craftsman who enlists in the cellar) that has built his own business on the solutions that he says to be wrong! ! !

the guy to make 3 holes in an aluminum tube would like to use a system with brushless servomotorization and cnc (or plc) that costs to eye and cross not less than 3000 euros per group.. .