2D Elbow Drafting Geometry
2D Elbow Drafting Geometry
(OP)
I'm trying to draw in AutoCAD a LR 45 elbow in plan view that is rolled to one side at 45 degrees. I need to find out if there are any resources that would explain the geometry or construction sequence associated with drafting such a thing.





RE: 2D Elbow Drafting Geometry
Read up a bit on vector algebra
here and others,
http://www.allegro.cc/forums/thread/591460
once you describe the angle (45º or any other turn angle) between the incoming pipe and outgoing pipe into and from the elbow's intersection and get an end coordinate, rotation of the plane of the elbow about the incoming pipe axial centerline produces the final coordinates of the end point.
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"Pumping systems account for nearly 20% of the world's energy used by electric motors and 25% to 50% of the total electrical energy usage in certain industrial facilities." - DOE statistic
"Note: Make that 99.99% for pipeline companies" - http://virtualpipeline.spaces.live.com/
RE: 2D Elbow Drafting Geometry
Back many years ago when helping out with the development of an in-house 2D CAD piping program, we worked-out a way to do this by using Autolisp but I forget how we did it. These days I have a goldfish's* short-term memory due to the onslaught of new software, methods, trends and currently-popular ways to replace paper and pencil.
Try creating a torus ("doughnut") in 3D Autocad and chop into sectors.
Paul
*Oooh, look, cool! A treasure chest!
<swim around>
Oooh, look, cool! A treasure chest!
<swim around>
Oooh, look, cool! A treasure chest!
[...]
RE: 2D Elbow Drafting Geometry
RE: 2D Elbow Drafting Geometry
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"Pumping systems account for nearly 20% of the world's energy used by electric motors and 25% to 50% of the total electrical energy usage in certain industrial facilities." - DOE statistic
"Note: Make that 99.99% for pipeline companies" - http://virtualpipeline.spaces.live.com/
RE: 2D Elbow Drafting Geometry
Cheers,
Paul
RE: 2D Elbow Drafting Geometry
.. Mission(s) accomplished.
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"Pumping systems account for nearly 20% of the world's energy used by electric motors and 25% to 50% of the total electrical energy usage in certain industrial facilities." - DOE statistic
"Note: Make that 99.99% for pipeline companies" - http://virtualpipeline.spaces.live.com/