development of u -calandrati profiles

[Oldwarper]

tolerance + - 5mm in diamerto

However the thing that escapes you and the big diameter for which you do not need to cut the head and the tail (then I can bend everything) and the important thing???? ? holder does not want to cut (Add) nada

but first what did he do, the spirals of licorice? ?

No, because with the calandra, it turns out to me that the terminals come out to you, depending on the distance of the rollers, but we never used it much.

However I confirm, we also use sw for the simulation of the folds, but in the end the developers must be controlled "from the truth" with the sheet that, presumably, will be used, hoping ceh the supplier gives us a sufficient consistency and in the molds we put all the tricks in order to be able to ovviate to the different characteristics of the materials according to the supply.

by little man, we won't be as expert as you in the displacement, but 40 years of "lamiera" a bit of experience maybe we have it, don't you think?

ah, we haven't come to the head of theoretical calculations yet. Do you give me two reliable figures?

 

[Fulvio Romano]

So, I'm an expert now explaining how to make precise sheets. I've been working for a while with the plates and finally I've come to a conclusion. if you draw a little overmetal and then you go to the yard strictly after the carpenters put it in operation...you will find your perfect sheet. . .

Okay, this was a joke, a joke, because I've been playing with the interpreter lately:biggrin:

to return to serious speeches. I have very little experience of sheeting, calandre and folds, but I would like to know what we are talking about.
I think I understand that this folded u must be inserted into a "tubo" and then welded. I think it's a structural ring. if yes, what kind of structure? If it's stuff not in pressure and high thickness, I would do in another way:
cut the bar as development of the internal circumference. In this way I will certainly have a length lower than the desired one. do not balance the ends, but I insert this "mode" inside the tube, possibly with a momentary horse to hold the ends. When I remove the horse, the "molla" will expand until it touches the tube. the balance to the tube and it's over. will remain space between the two ends of the bar. question, does this fact have structural influence? if efforts do not have important local characteristics (type pressure vessel), those few centimeters of hole should not be a great harm. to the limit weld another piece to close the hole.
possibly, if there are more than these rings, it would be necessary not to align the holes.

Okay, it's very dirty, but it should be the fastest and cheapest way.

Of course, you have to understand the application a little better.

 

[andle11]

@ fulvio:
dirty or unclean, it seems to me a brilliant idea:

 

[KRLE]

:finger:
In fact – I’m still waiting for some practical advice or at least I haven’t heard a tip for a software that can be used for our applications

 

[Fulvio Romano]

:finger:
In fact – I’m still waiting for some practical advice or at least I haven’t heard a tip for a software that can be used for our applications

the hypothesis of post #42 is to be discarded? Yeah.

 

[maxopus]

:finger:
In fact – I’m still waiting for some practical advice or at least I haven’t heard a tip for a software that can be used for our applications

I'm trying to give you advice that I believe is reliable.

there is no specific software that is able to accurately return the development of hot profiled elements (unp, ipe, inp, hea, heb ... etc.).
there are procedures that can bring you very close to the desired result and you have to verify that the procedure is correct, because the result depends on:
- profile section;
- towards bending (a "u" can be folded in 3 ways and you will have 3 different developments);
- steel quality, because plastic deformations of a s355jr are different from a s235jr and therefore will give you different developments.

a data on which I would reason and do the first test is to calculate the development compared to the y-y axis of the profile.
If development coincides with the axis above, we are riding.
otherwise we establish what is the distance of the above axis and make the second attempt.

question, do you have a normal hot profile with the indication of x-x and y-y axes?

 

[re_solidworks]

I'm trying to give you advice that I believe is reliable.

there is no specific software that is able to accurately return the development of hot profiled elements (unp, ipe, inp, hea, heb ... etc.).
there are procedures that can bring you very close to the desired result and you have to verify that the procedure is correct, because the result depends on:
- profile section;
- towards bending (a "u" can be folded in 3 ways and you will have 3 different developments);
- steel quality, because plastic deformations of a s355jr are different from a s235jr and therefore will give you different developments.

a data on which I would reason and do the first test is to calculate the development compared to the y-y axis of the profile.
If development coincides with the axis above, we are riding.
otherwise we establish what is the distance of the above axis and make the second attempt.

question, do you have a normal hot profile with the indication of x-x and y-y axes?

the second proposal is what I had recommended to my first intervention and usually compute the developments so.
In the companies I work with, however, do not make internal calndrance and therefore could be that the bending machine applies corrections that I do not know. I believe, however, that these corrections are not greater than those required to compensate for the elasticity differences of one steel casting from another, therefore in my opinion they will have to be satisfied to approach the correct development, to perfect it for this job if the casting is unique and to start from the same point in a future job where the material will be of a different casting/material. They can't get the impossible, that's all.

 

[maxopus]

the second proposal is what I had recommended to my first intervention and usually compute the developments so.
In the companies I work with, however, do not make internal calndrance and therefore could be that the bending machine applies corrections that I do not know. I believe, however, that these corrections are not greater than those required to compensate for the elasticity differences of one steel casting from another, therefore in my opinion they will have to be satisfied to approach the correct development, to perfect it for this job if the casting is unique and to start from the same point in a future job where the material will be of a different casting/material. They can't get the impossible, that's all.

true king.... is that I lost myself in this psychodrama :smile: and now I have looked calmly.

 

[Oldwarper]

I apologize to all users, but I violently "posed" the discussion to bring it to the sense from which it was gone. Unfortunately, for two times, it was flaming (and saying that the subject was not the most 'hot'...) because of a series of weather.

I hope readability remains enough.

a note for the president: cutting his posts was as painful as cutting me a forearm:frown: (no, eh? we make an incarnied nail...:biggrin, but the duty first...:mixed:

 

[Er Presidente]

...
a note for the president: cutting his posts was as painful as cutting me a forearm:frown: (no, eh? we make an incarnied nail...:biggrin, but the duty first...:mixed:

You have no idea how painful it will be to "calandrarti" to u (rovescio) without k and without "development"! ! !

p.s.: well! we just missed this, be "seated" like a normal "utonto"!
But it'll all come back! ! ! ! !
:biggrin:

 

[SolidUser]

I'll make you one.
what difference is between the above and this phrase:

1) this is a linear development.
2) I have highlighted it because it is linear and does not consider the bending factors
3) is an aid to the development of such forms, it does not give an exact measure (and here it would be better that the help specified it, I did not subhand it, maybe so, n.d.m.)
4) gives an approximate measure, but since it is not a specialized sw you can settle
5) if you need more precision you need specialized software (and also for those a test it always takes, n.d.m.)

It's all right, but we're adults and vaccinated.
If a command gives an approximate solution, it's necessary to know, because whoever doesn't know it and trusts it, then he can start loving surprises.

One can guess, looking at the parameters he asks and the result, but if he asks and doesn't respect them, at least a non-bypassable warning (not enough the help) would take us. even if it's a "beta" function.

I wrote what was reported because it annoys me the right criticism to criticize.
as a hulled user of solidworks and especially on the sheet environment, as it is believed to be and also participant as a beta tester, knew or had to know that this function has the only purpose of being able to give a flattened form to these templates.
no cad is able to calculate the correctly development of these forms.
all cads follow the linear approach to calculate development and no one takes into account the stretching and compression of the material.
everything was obvious, even if not mentioned in the help, as well as deducted from the inputs needed to complete the function.

I also continue to be of the idea, that it is better to have a flattened approximate that not to have it at all.

 

[Oldwarper]

I didn't think it was a criticism just to criticize. However, he pointed out something that maybe if he came out of the filterless beta, he could have caused problems to those who are not "scafated" like you, him and me on the sheet. We all know the unreliable development of certain pieces. for this I have never tried to waste time in bending tables, not making us repetitive pieces and in which a "normalization" is applicable.

Then it can happen that a non-experienced sheet metal (and computer developments, maybe a service) takes as reliable a reliable coe result is not. and problems arise.

I don't tell you how many times to my owner I have to say that the development of the pieces made with a cad that cost him so much and that they had so much promise are not reliable and are still to prove... and how many insults every time I have to get caught because "the comuter bought it on purpose, he spent so many $$ (sic...) and pretends a program that makes the developments of a complicated imbuted without evidence, which means I'm not able to use it, etc...". I'll put on it, a little experience and a little bit by hand and the risutato comes out. and everything well until the next time.

Now you tell me something. Do you think the commercial will go to tell those who buy the soft (it will be difficult the technician who uses it, practically never) that the data developments are approximate but a good base of departure or that new function just out, there is already the correct development and with what they save in evidence will repay the program? What case do you think happened to me?

then, once again, we all try to stay in the tracks of correctness. If someone behaves incorrectly there are private moderators and msg.

 

[MBT]

I think I've already brought my experience of a few years ago...
design a hopper
usually they were made to the "segugio group", with four quotas put on the cross, just the fundamentals of encumbrance, volumes and interface
I put myself on a commitment and the design for good
folded sheets, welds, chinfrines, rays and rams... to development
all the kit to help the welding bending machine... A lavoretto abarth!
I feel some time after the supplier for other reasons and, feeling proud of the work done, I ask him if the hopper was "pleased" at development level.
"ah, look, I took the main odds and threw the rest away."

What? Why? ? "
"eh, you did a good job, but you assumed I had a knife for the fold. I didn't... I have another one, and not always that bending machine is available. Then I prefer to arrange time for time with what I have freed in the house. sometimes, if I have the machines occupied, I do not make folds but balance the walls... "
:36_1_4:

moral:
but are we sure to lean so much to give the ready parrot in the workshop is necessary and/or appreciated?

 

[maxopus]

moral:
but are we sure to lean so much to give the ready parrot in the workshop is necessary and/or appreciated?

mister is always the problem though you could easily solve.
You should have 5 minutes of calm, raise your phone, call the tertist and ask: "You send me by e-mail a table in which you indicate to me for every thickness which bend radius you use (or knife-cave)?"
done this should be prepared a folding table (with the data provided by the bending machine) and model with that.
in brackets this would help a lot because, if you want to make the piece to another third party, just change the folding table and the data are updated without unsmatch in the control of all the folds.

 

[MBT]

mister is always the problem though you could easily solve.
You should have 5 minutes of calm, raise your phone, call the tertist and ask: "You send me by e-mail a table in which you indicate to me for every thickness which bend radius you use (or knife-cave)?"
done this should be prepared a folding table (with the data provided by the bending machine) and model with that.
in brackets this would help a lot because, if you want to make the piece to another third party, just change the folding table and the data are updated without unsmatch in the control of all the folds.

true, with derogations and exceptions
the small manufacturer has a narrow circle of suppliers, with which the u can certainly speak and get the right info to correctly model :smile:
in large companies... Not easy!
You don't know the shopping office with those who fought this time. will give the piece to the guy or to the caio? and if you decided to try sempronium, which made him an aggressive price to predne the customer?
What if he goes to the china?
Not just...
if the machine is "standard"??? What do I do? sending in production every time with change reserve to update the folds depending on the supplier? that, for the above reasons, may I also not know?

 

[maxopus]

about the discussion though, to close the circle and try to make it useful.
we have seen that flattening a profile does not serve in terms of development calculation.
if you allow I would have a suggestion to propose.
when a hot profile falls, at the empirical level you can understand what is the neutral axis.
Just take a piece along a tot, give it a radius of curvature and calculate what is the neutral axis.
made this, insert into a start part (or model part) of your profile a curve (a circle arc in this case) that matches your neutral axis.
When you go to change curved rays and lengths, measure the length of the above curve and get your development.
It is an empirical method I repeat, but I think it is very close to the real data.

 

[maxopus]

true, with derogations and exceptions
the small manufacturer has a narrow circle of suppliers, with which the u can certainly speak and get the right info to correctly model :smile:
in large companies... Not easy!
You don't know the shopping office with those who fought this time. will give the piece to the guy or to the caio? and if you decided to try sempronium, which made him an aggressive price to predne the customer?
What if he goes to the china?
Not just...
if the machine is "standard"??? What do I do? sending in production every time with change reserve to update the folds depending on the supplier? that, for the above reasons, may I also not know?

If you want to avoid chapels this is the only way.

another method that I use with a couple of lamierists is to send him the step of the folded piece.
I use pro/e, they use swx.
import the step, change the rays if not they garb, attribute the k factor and develop the piece.
In this way I'm protected, because I don't care about developments, the important thing is that the folded piece is in place.

 

[re_solidworks]

I close the discussion as technical opinions have been provided and all the interventions that are followed are out of place and in contrast with what asked by the moderators.