Hello
I would need to have the development of a "hook" drawn in sweeping as well as the rolling hill of it.
Thank you in advance.
Hello
Would it be possible to have a screenshot to give yourself an image of what it looks like?
@+.
AR.
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Hello Lucie,
The hook is simply a sweep of a circular section, so what you are asking for is not the unfolded, but the developed length which is exactly the sweep which must be the center of the circular section, the is the length of the round necessary to get this hook that's simply.
For the unfolded is exactly for a sheet metal shape that we get in the sheet metal module which is very well made to have it unfolded ...
Come on @+ good luck.
AR.
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Hello
to get the LD you just have to display the sketch and click on each part to get the LD but in your case it must be in the middle because it will be the neutral fiber. See example in PC
ld.jpg
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And here is a fold-out iron if you ever want to see how it is done
astuce_pour_deplier_un_fer_rond.sldprt
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Hello Lucie,
Be careful, the unfolded length will depend on the bending radius and the diameter of your wire.
Depending on this, the folding K factor will be different (neutral fiber).
For example a part I made yesterday, a sheet metal bent at 120° with two sides of 65mm, I have an unfolded of 126.6mm instead of 130mm .
Thank you all amk
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I don't understand anything anymore
I think I have a deficiency of neurons
unfold at least the length of a tube with X bending
corresponds to the neutral fiber of this tube
@+
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That's exactly what gt22 is all about, that's why I wrote in a post
"to get the LD you just have to display the sketch and click on each part to get the LD but in your case it must be in the middle because it will be the neutral fiber. "
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Yes, but calculating the Developed Length just with the sketch of the finished product doesn't take into account the loss at the bend I think.
In any case, in production with us, this is what we do to avoid having problems with length in the final result.
Hello
Provided that I understood the question, the calculation is quick here.
Our tube = 1 small straight line pL + 1 elbow + 1 straight L + 1 elbow + 1 small straight line pL
The 2 small lines (pL) of the extremities are considered to be of equal length.
An elbow with radius R forming an angle of 180°, i.e. the length of the elbow = R*pi. And there are 2 of them.
i.e. pL + (R*pi) + L + (R*pi) + pL
i.e. length of the tube = (pL*2) + L + (R*pi*2)
Kind regards
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@ m legras
Do a test and you'll see that the neutral fiber corresponds exactly to the unfolded length of your piece
@+
PS
Inner fiber compresses
Outer fiber lengthens
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@gt22, thank you for this info, I pass on the knowledge to the office.
@+ :)
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Being in the field, I confirm what gt22 says about fiber. By the way, that's what I wrote in my 1st post...
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Hello everyone, I'm coming back to the subject because we are in the middle of developing tube bending.
On Ø42,4 ep. 3.2 in stainless steel, a straight part of 1320, an R250x 60° handlebar, a straight part of 775, an R250x60° hanger and finally a straight part of 1320, we have a part with 40mm less than the press (neutral fiber length).
Has anyone ever had this case of loss at the bend on tube bending? And do you have methods for calculating the loss at the bend according to the sections/thicknesses?
Thanks in advance
Hello @ m legras
So it's a tube with an outer diameter of 42.4
and a thickness of 3.2
Are you sure that your bending radius is of course the neutral fiber
redo your piece
via a 3D sketch (neutral fiber only)
if your bends are not on the same plane
Control your ribs well every straight part and every bend
in theory and practice the dimensions of your neutral fiber will correspond exactly to the dimensions of the tube made That you will do via a scan
post your part in parasolid we don't all have the same version
or post images of each action of your procedure to understand where your problem comes from
PS: it's clear that if your rays are rays other than your neutral fiber for example (spokes on the inner fiber)
your ribs will be wrong
@+ ;-)
Hello @gt22,
my Solidworks part is well in balayage compared to the neutral fiber.
My part is made from a 3D sketch and a mechanically welded element function (library of circular profiles).
I don't have any worries about that. It is when made on the digital bending machine that the result has a difference of 40mm.
We certainly have a loss at the bend like for sheet metal.
So it's probably a problem
adjustment or coordinate on your digital bending machine
try to do a test with 90 degree hangers
with the same radius 250 and the straight parts ditto
on a test part
Clean, check and check your straight and curved lengths
as well as your total length which should be the same as your neutral fiber
@+
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