Hi all
I would like to do a numerical simulation on a tool to do a biaxial tensile test due to the offset of the tested part from the center of the jaws of the machine, so I did the necessary work in the static like defining the material with the C45 for all the tools and the aluminum alloy 6000T5 for the part, as well as boundary conditions where the fastener is at the bottom and the loading is at the top.
As for the connections, I used the type of bolts to fix the part and the connection drafts for the square at the bottom where it is attached to the part, this is after the failure and return without result of using a square weld bead, But despite all this, there is a message that "the deformation is too great"!!
Well, I really think that the problem is caused by the type of analysis because in the large deformation for example with Abaqus we used the explicit solver which is faster and more robust than the implicit solver and therefore certainly the problem is nonlinear because of the geometry, but my goal is to validate the resistance of my tooling, and this on the fact that SW Simulation predicts that the big deformation will be on the part tested!!
I need to make this tool as soon as possible to give it a try and have a little fun ;-)
But really the actual tooling is bigger than that.
Have a good weekend
Kind regards
assemblage2.zip
Hello @firasschafai
For such a simple problem, the debate is not between Solidworks and Abaqus (especially for static) but to correctly parameterize the elements before starting the simulation.
In your simulation settings, nothing or almost nothing is right.
I'm preparing a more complete answer for today I hope (but there's a lot of work to be done).
It's going to cost you a good mechouia + madmouja and to make you forgive some baklawa ;-) And of course a small glass of boukha to settle all this.
Kind regards
1 Like
Good evening @firasschafai
Here is the result with remarks and advice.
As you wanted to test the tool above all, I didn't overly refine the hinge where you would have had to have a part of the axis allowing a rotation. For the same reason I didn't use the bolt connectors because to test the tool it doesn't change anything.
I know you're in a hurry right now with your graduation deadlines (that's why I've helped you a little more than I should on this forum). But I strongly advise you to do a solid training on simulation, for the moment you are not there (if I may say so).
A mechanical engineer who does design must know in detail how simulation works, especially if he uses it himself.
At your disposal if you have any questions about the attached document ;-) ;-)
Kind regards
remarques_sur_simulation__v1a.pdf
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Hello @Zozo_mp
Frankly, I couldn't find the words to thank you because really I haven't found someone who makes people courageous and supports others like you, and it doesn't bother me if I say that your help me feel good during these 3 years from the first bachelor's degree until now when I finish with the engineering training.
Really in all my questions here in this forum, I took a lot of things that are very very interesting and I approached them as the laws of ord, and it's thanks to you and your patience over time.
I turn to your advice because words never end, and I don't forget these good moments of interaction and it's time to talk about the interactions ;-)
Before starting the simulation, we need to know the objective of this study, so we need to have a tool that transmits all the tensile load to the hinge and therefore have a tool that does not deform.
Well I don't know why you change the location of the boundary conditions with the embedding at the bottom and the loading at the top (you selected a flat surface and really where the pins are) but that's not a problem.
What attracts me is the plane support, it's really very practical.
Exactly, almost every day the problem of contact is in the majority of simulation problems and the proof in the analysis with SW simulation, the slowest task is to "solve the contacts"
I'm going to move my settings, and I hope I return with nice result close to you.
Kind regards
PS: Yes yes I don't forget what you need for the table and you first deserve the couscous / keskesu to set up the foundation and load the supports well, then as you wish with the baklawa, but I'm sure you forget the famous desert of support what is called Jwajem ;-)
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Hello @firasschafai
You say ( I don't know why you change the location of the boundary conditions with the embedding at the bottom and the loading at the top (you have selected a flat surface and really where the pins are)
Simply looking at the section of the bottom piece which is 47 mm in diameter if something were to give way (break) it would be the pin (Ø 13 ) by shear and in no case part 1. So whether you put the fixed connector in the hole of the pin or where I put it, it doesn't change anything except that I have a larger surface area by putting on the end of the cylinder that is part 1. Your solution is good and mine is not wrong ;-)
Kind regards
Hello @Zozo_mp
I've found something that gives me the energy to get things done, but I'm not comfortable with safety.
Unfortunately 0.2 security is nonsense!!
For loading 40000 N is a lot, isn't it?
Kind regards
@firasschafai
I see that you used the axle connector for the BRAVO hinge ;-)
40000 N yes way too much but it's a test to see how far it would resist and how the tool behaved more than the hinge.
With 2000 N + bolt use to see how the hinge would behave, in addition to the behavior of the tool, you have a safety coeff greater than 8. On the other hand, at 2000 N, the hinge has a CS less than 1 (see image).
It would be interesting to see in dynamic simulation how far we can see the deformation of the hinge. Snifff I only have the static simulation version)
For the safety factor you have to be careful because the representation proposed by Solidworks is totally stupid (you have to reconfigure it)
Be careful, the flat connector sliding on the side of the bottom piece is useless since you already have a fixed connector. A fixed connector removes the three DDLs.
couleur_coefficeint_de_securite__vue_2___2021-04-06_16_50_37-window.jpg
Oupsss! I forgot to tell you!
For the safety factor you have to set it better than the stupid thing of SW
Click on modify the definition ==> and put a coeff of 8 or more
click on "graphic option==> Choose the color (I chose green for the max coeff= so we stay close to the Red = Danger and green it's okay
Then also select Min and MAx Annotation you will see the area with the lowest Coeff.
In the Don't forget to specify "General" and not "Scientific" graph option, this allows for a direct, unambiguous reading
Kind regards
Good evening @Zozo_mp
I find it like this
The thing you tell me is good, when I see the green is dominant on the tool.
Okay, at this point, it's fine, but as I mentioned before, I'm just going to make this tool so I can try it on a 90° test and easy to do the other 2 tests, but the big task is with the other full tool so I can identify 200 hinges with 3 types of tests so we're talking about repeat, This is called cyclic loading and therefore fatigue. So, to make sure that the 2 clevis and the 2 pins work in frequent conditions and on the entire notch of the clevis that will carry the mother tool!! I can with the CS = 8 guarantee them ?
Kind regards
20000_n_avec_cs_8.png
Hello @firasschafai
Very good ;-) Even with a coefficient of 5 it would be enough : but as the material cost represents nothing even if your tool is slightly oversized, no one will say anything.
ANYWAY for small hinges it would surprise me if the manufacturer gives a CS. It usually only gives an indication of the radial and axial tensile strength, sometimes in angular swing but rarely more.
Although not the request of your sponsor you could by simulation (with Solidworks Pro or Pro premium) have the results with vibrations and resistance over a number of cycles (with or without natural frequency).
Courage, you're on the right track ;-)
Kind regards