[kolapoasafa]

Hello All,

I am having trouble importing a pipe geometry from Inventor to Gambit using .igs or .stp files. The geometry is made up two concentric pipes, in which the inside pipe is helically buckled. I therefore used the “Coil” tool in Inventor to create the inside pipe while the outside pipe was created by extruding a circle around the helix. However, the buckled inside pipe showed up as a single line as shown in fig 1b when imported to Gambit. When I tried to extrude the circle along the single line helix in Gambit, I was having an error message that says the axis of the circle is parallel to that of the helix. Then I went back to Inventor and recreated the geometry with the inside and outside circle on the same plane as shown in Fig 2a and the result of my import to Gambit is shown in Fig 2b.

I will appreciate your helpful suggestions to fix this problem.

Thank you.

[-mAx-]

I don't see how look like your pipe.
It is straight?
Do you think you cannot create your geometry within Gambit?

[kolapoasafa]

The outside pipe is straight while the one inside is a helically buckled into a spiral shape. However, the inside pipe will appear straight in the drawing (even if i show the full length of the pipe) because of the long pitch of the helix and the long length of the pipe itself.

It is very tough to create the geometry in Gambit because the inside pipe helix has to revolve 360 deg. a couple of times, with constant pitch length between revolutions, while in contact with the surface of the outside pipe. If you know how this can be done using Gambit, I will very much appreciate your guidance.

Thanks.

[-mAx-]

with sweep surfaces can you do something.
But as it is already built in your CAD software....
Ok since the outside pipe is a straight one, it will be easy to treat it after in Gambit.
So try to modelise you inside pipe (alone) with your cad sofware and export it into gambit.
If it is successfull, you will just have to work with boolean operation for substracting (or whatever with your outside pipe).
Hope you understand what I mean