Minimum Sizes Of Custom Shapes for Utility Lines

I was asked yesterday to look into an issue that a customer was having with creating Custom Utility Shapes for conduit for cables being laid in a major highway project. The specifications provided were as follows

The conduit set was 6 cylindrical conduits together in a 3 x 2 arrangement (3 columns and 2 rows) where the conduits were outer diameter 110mm and inner diameter 95mm and the conduits were 50mm spaced horizontally and vertically as shown below.

The problem was that the user was trying to create a custom utility shape that could be used to create the 3D model of the conduit for use in visual clash analysis and also to build 3D trench models for the machines and surveyors on site.

The issue they were having is that while you could not select each pair of circles to create the individual pipe elements nor could you select the outer circles only to create the pipe elements - why is that?

I researched this for different shape objects and found an internal limit in the software that for circles stops rendering at 0.057m radius. I also found that rectangles are limited to a side length of 0.045m.

I imagine that the development team did not think that pipes and cable conduit would get smaller than that, however in researching this, it is common to have pipe type conduit that is 50mm outside diameter and 43mm inside diameter and for fiber optics it can get as small as 16mm outside diameter and 10mm inside diameter.

Can anyone comment on the US equivalents here please as I would like to get US and Metric sizes accommodated if we can get the limits here changed.

I also found that if I select an inside diameter circle and outside diameter circle to create “pipes” then they render as chorded circular pipes, however if I only select an outer circle that they render as a solid but show up as a Hexagon in the graphics.

Hope that this helps


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