topic Re: assign a pressure force to tube section in Inventor Forum

assign a pressure force to tube section

Anonymous — Mon, 15 Feb 2016 11:07:46 GMT

Dear Engineers,

I am using Tekla Structures to design steel structures, but I couldn't check joints in Tekla.

So I want to do that in inventor and I could be able to export my connection to inventor.

I assigned my consraint and materials in inventor but when I try to assigned a pressure force to tube sections face, it can't assigned uniformly to tube face.

do you know how can I assigned this force to tube face uniformly?

Re: assign a pressure force to tube section

admaiora — Mon, 15 Feb 2016 11:20:50 GMT

Hi,

you have assign a Force, not a Pressure.

Anyway, the force is distribuite in a uniform way, the yellow force is only a glyph representation

Re: assign a pressure force to tube section

Anonymous — Mon, 15 Feb 2016 12:14:49 GMT

I assume You want to convert a centric force to pressure.
Simply find area of the solid (the section of the pipe, wall) and divide the force with it.

Then You got the pressure. It should be possible to add this pressure to any flat face, as far as I know.

Re: assign a pressure force to tube section

Anonymous — Tue, 16 Feb 2016 07:51:43 GMT

pressure = force / Area

so I assigned a force to area.

and when I checked my results it gives me wrong results because force is not acting on surface uniformly.

I am wondering about that can inventor make a rigid element on tube surface which I gave above.

I add a link picture which I want to mean.

https://knowledge.autodesk.com/support/simulation-mechanical/learn-explore/caas/CloudHelp/cloudhelp/2015/ENU/SimMech/files/GUID-B278851D-89B8-4EAB-A513-4871C27D0692-htm.html

Re: assign a pressure force to tube section

admaiora — Tue, 16 Feb 2016 09:58:32 GMT

What are the results that are you referring?

Re: assign a pressure force to tube section

Anonymous — Wed, 17 Feb 2016 07:04:37 GMT

Dear admaiora,

thank you for your reply,

I want to give you my results,

actually I have a normal force (P) = 300 kN = 300 000 N

the tube section is D168,3*5 mm (R=168,3mm and thickness = 5 mm)

so my crossection area = 3,14*168,3^2/4 - 3,14*163,3^2/4 = 1301 mm2

I am using S235 structural steel which Fy = 235 MPa and Fu= 360 MPa

G=P/A = 300 000/1301 = 230 N/mm2 < 235 N/mm2 so the section is smaller than the yield value of steel in hand calculation.

but when I acted this pressure to tube section the results doesn't close to hand calculations because it takes the pressure in eccentricaly and this cause the additional moment forces.

G = 300 000/235

Re: assign a pressure force to tube section

Anonymous — Wed, 17 Feb 2016 09:13:24 GMT

I'm no expert on analyze but how long are these pipes?

If they are long they will bend/deform and the pressure will be eccentric.

When the overall load ratio is G=230/235MPa with hand calculation I would

rather thrust FEA.

I think You got to increase wall thickness in the pipes because it's

deformation who decide if this is acceptable or not.

Re: assign a pressure force to tube section

admaiora — Wed, 17 Feb 2016 09:39:02 GMT

Edited

Re: assign a pressure force to tube section

admaiora — Wed, 17 Feb 2016 09:44:36 GMT

The analysis is correct.

The eccentricity si correct and is due to the square plate deformation.

You can try to fix the plates faces to note that.

Re: assign a pressure force to tube section

Anonymous — Mon, 22 Feb 2016 07:21:23 GMT

thanks for your helps,

I want to ask a more question about this model,

after stress analysis finished the bolts disappared,

is it possible calculate stresses in bolt sections with stress analysis.

or can I define bolts in this model to calculate stresses which acts to bolts.

Re: assign a pressure force to tube section

Anonymous — Tue, 23 Feb 2016 14:45:00 GMT

can anybody help for this?