inventor simulation - precarious simulation screws

[Jeky]

Bye to all,
are an inventor simulation 2011 user and are struggling with the fem analysis of a s355j2 sheet metal flange and fixed by clamping screws on part still in s355j2.
I have the problem of simulating the preload of the vines Is there someone who solved the problem in a similar way? I have seen in the community a discussion about it but none of the participants used inventors who do not have the tools proposed.

thanks and good Easter to all
j.

 

[meccanicamg]

I don't remember exactly if it's just solidworks or even inventor, but there's the specific bond of the bolt. If you don't have to create physical bolting and apply precarious forces and what else to then load the metal structure with forces.

in the first appropriation the n vines breed as incastri... then it is not true, therefore as approach to reality the connection "bullone" is adopted.

 

[Jeky]

I don't remember exactly if it's just solidworks or even inventor, but there's the specific bond of the bolt. If you don't have to create physical bolting and apply precarious forces and what else to then load the metal structure with forces.

in the first appropriation the n vines breed as incastri... then it is not true, therefore as approach to reality the connection "bullone" is adopted.

thanks for the answer,
inventor 2011 unfortunately does not have the bond "bullone" and not even spring.
I created an axieme that includes the flange, the drum on which it is fixed through the 12 m24 screws that I have realized and placed. I set the constraints and contact constraints. the model responds well but not having preloaded the screws the flange goes too far.
to solve the problem, I would have thought of two solutions:
1) for each screw apply two forces, equal and contrary, in the front and rear contact surface so that it is an internal action.
2) impose on the screw one and such that f=k*dl gives the preload with a very small extension. but this is a method that is too gross.

What do you say?

 

[meccanicamg]

thanks for the answer,
inventor 2011 unfortunately does not have the bond "bullone" and not even spring.
I created an axieme that includes the flange, the drum on which it is fixed through the 12 m24 screws that I have realized and placed. I set the constraints and contact constraints. the model responds well but not having preloaded the screws the flange goes too far.
to solve the problem, I would have thought of two solutions:
1) for each screw apply two forces, equal and contrary, in the front and rear contact surface so that it is an internal action.
2) impose on the screw one and such that f=k*dl gives the preload with a very small extension. but this is a method that is too gross.

What do you say?

I also checked in inventor 2012 there is no previous exhibit (it is only in solidworks that there is).

1) seems to me the correct solution by applying the two equal and contrary forces on contact surfaces as action/reaction of the screw/magnet

2) you could basically forget about the intrinsic existence of the screws

I would say the truth, if you have correctly sized the screws, you should come to check that the individual screws are rigid and inextricable if sufficiently oversized, therefore do not undergo stretching under the operating load.

or, apply the material to the screws so that they are also real elements of simulation and therefore you will have that they also have a form of elasticity and consistent and the relative loads of breakage and yield adequate.

 

[Jeky]

I also checked in inventor 2012 there is no previous exhibit (it is only in solidworks that there is).

1) seems to me the correct solution by applying the two equal and contrary forces on contact surfaces as action/reaction of the screw/magnet

2) you could basically forget about the intrinsic existence of the screws

I would say the truth, if you have correctly sized the screws, you should come to check that the individual screws are rigid and inextricable if sufficiently oversized, therefore do not undergo stretching under the operating load.

or, apply the material to the screws so that they are also real elements of simulation and therefore you will have that they also have a form of elasticity and consistent and the relative loads of breakage and yield adequate.

the screws I had inserted them with the properties of the real material for a cl. 8.8. on one I have a punctual peak of seq (vm) of 1410 mpa on the pole but all around schende to negligible values.

Now I am making a simple model by applying point 1) and then I will tell you.

thanks and good Easter to you and family.
j.

 

[meccanicamg]

the screws I had inserted them with the properties of the real material for a cl. 8.8. on one I have a punctual peak of seq (vm) of 1410 mpa on the pole but all around schende to negligible values.

Now I am making a simple model by applying point 1) and then I will tell you.

thanks and good Easter to you and family.
j.

attention that it is easy to have high punctual values that obviously do not have physical sense but only the effect of applying a force on a small area and does not correspond to reality.

always and however it is necessary to do structural calculations and verification by hand according to regulations cnr uni 10011 (retired) or eurocode 3.

fem analysis cannot be used as "great truth" and only instrument of verification.

thanks and good Easter to you and family too:finger:

 

[Jeky]

attention that it is easy to have high punctual values that obviously do not have physical sense but only the effect of applying a force on a small area and does not correspond to reality.

always and however it is necessary to do structural calculations and verification by hand according to regulations cnr uni 10011 (retired) or eurocode 3.

fem analysis cannot be used as "great truth" and only instrument of verification.

thanks and good Easter to you and family too:finger:

Thank you again.
j.