Profile Transfer

[sakthi06dec]

Can someone help me to transfer a tube profile(circumferencial profile of a bent tube at its bend) on a paper/graph??? Please suggest me a method as simple as that!!!!

Details: Actually I have to conduct a First off Trials for tube bends before putting the bends for batch production. First bend for each spec and dimensions has to be analysed for Flow area, Ovality, Thinning and flatness. For calculating FLOW AREA we use a method where we cut the tube at the desired location and make the imprint on a graph paper and then we calculate it from graph. But I am interested in calculating flow area without destructing the tube. If I am able to transfer the OD profile, then by measuring thickness (using Ultrasonic gauge) I shall transfer the ID. This is my problem statement.

[jboggs]

Use a shadow silhouette.

[sakthi06dec]

tube.JPG

I need to have an outline like the image above; i.e. the circumference of the tube @ bent portion. Silhouette can be useful to transfer the entire outline of a tube and not the circumference at specific locations.

[RWOLFEJR]

CMM... Coordinate Measuring Machine... Would be the simplest and most precise method of measuring and transferring the profile... Without cutting the tube at the bent section. Bad part is a CMM is pretty expensive.