Hello
I am trying to determine the forces on the anchors of this system in order to fix it in the concrete. The weight of the trolley plus the load will be about 3500N.
Can you help me?
linkoa.png
linkoa.png
Hello
To do this, it is necessary to have a very precise idea of the load descents, especially when they are subjected to buckling. It is especially the small jib that will have the biggest deformation, the very long beam may have more or less deflection depending on the result on the small jib crane.
So unless you are very good at calculation, it is better to go through the simulation which will give you the result on the plates that will receive the bolts. It is these efforts that will help you choose the dowels according to the supplier characteristics.
The effort on the ankles is not the right formulation in my opinion.
Kind regards
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Thank you for your quick answer Zozo_mp, however I only have Xpress simulation which allows me to carry out the tests of only one part. I did tests on the large beam as if it were on two supports and the small recessed one with the load at the end. The results are satisfactory.
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I just saw your image and I think the result gives you a false security because it doesn't take into account the bending of the small stem at all.
In addition, this result does not tell you anything to answer your initial concern which is related to the effort to be expected for the fixing anchors.
In addition, this does not take into account the IPN on wheels and the large offset beyond the small stem. Also, you have to simulate a swing with an offset load of 350 kg when the IPN rail is extended and the hoist is located at any end as in your first image. You must also take into account the castors of the IPN and the hoist (recessed or non-recessed castor. There are other points to discuss but this goes beyond your request.
Kind regards
Quick question: is it a student job or is it for your company?
I am a work-study student but it is a company project, my start of the school year is Monday I hope to be able to discuss this subject with my teachers. The large offset is an additional constraint for sure, it was asked of me for reasons of size. I am in contact with a control body to validate the product, they have not yet answered me with the documents to provide. In fact, there is a load of 200kg but you have to consider a coeff of 1.5 the load for a manual hoist or 1.25 an electric hoist + the weight of the jib and the chain hoist .
Hello
Can you post your ASM using the Pack and Go function. This will allow me to look at the subject more precisely.
So that we can exchange can you make an image where you will name each element. What intrigues me is the telescopic part at the end which is in my opinion the most critical part than the IPN, it is the axles of the casters that will eat the whole load with a leverage effect that multiplies the efforts.
Are you the one who designed the model or is it the company because some points are curious.
A small friendly remark , it is not by increasing the theoretical load that we increase the safety factor. You have to think about the MAX load (200 kg) which will be written in large letters on the lifting system. Look at how to calculate a safety coeff which is theoretical since it will give theoretical indications that are beyond the elastic domain (cf the ruin criteria).
Kind regards
It's a model that I designed because I can't find a trolley for the application I need, I calculated the reaction on the casters in static in order to choose their capacity, I know that there are two wheels out of the four that won't be used much, I can't even be in contact with the rail but I don't think I can remove them, what do you think?
As for the coefficient I'm talking about, it's the control body that told me that for this kind of system it hangs a load of 1.5x to carry out the tests. Should I start on this basis or stay on my 200kg with a security coeff that will accept the tests carried out.
I'm trying to join the Pack
Kind regards
asm_00_palan.zip
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Ok well received I'll look at this in a moment
Kind regards
Good evening Emilien
Here are some results.
I simplified the model because for the simulation all the round bolts, etc... are useless because the objective was to see how the anchor plates and by the same token the bolts reacted. I only put four fixed points to replace the bolts and well nothing happens at this level. However, I did not put a remote load off-center in relation to the axis as would happen in case of swaying.
On the other hand, if there are problems, it will be with the connections of the trolley's wheels. I invite you to do a simulation on this part. I think it's up to your teachers to guide you on this point and especially to give you the technical means to do this simulation.
In the attached reports I have put the max load and the max deformation in static is only 32 mm and the safety coeff is almost everywhere at 4. Look at the design dissection that shows the most charged areas within the material.
Kind regards
PS: I allow myself a mini remark on the gussets of the frames. It is customary to put this type of gusset on the wings of the IPN and not for two of them on the central core of the IPN. See with your teachers the different types of connections between a vertical and horizontal beam. Your choice is not the most classic, and it is not a problem in this specific case, but hey: the state of the art is always something to get closer to. IMHO
asm_00_palan__zz-statique_2-1.pdf
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Hello
If I interpret your analysis correctly, there would not be a big effort on the pegs and the structure would therefore be well sized, I did not specify but the wheel axles of the trolley on the front part will be welded on the plates.
For the simulation part of the trolley I will discuss with my teachers, my start of the school year is Monday.
I take note of your remarks and thank you for your help.
Kind regards
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