Plotting curvature and bending moment

Forum|Forum|7 years ago
March 4, 2019
4 replies
2858 views

Hi, im new to Mathcad and this forum.

Im doing a project at school about wire straighteners. Im trying to calculate the height to set the straightening bearings to get straight wire at the end of the straightening unit. i figured out the equation to do this but i want to plot the curvature and bending moment of the wire for a distance x. I dont really know how to do this im still in engineering school learning and not that good with Mathcad. I hope some of you could help me, it would really improve my project.

Example:

Curvature+bending.JPG

I know the position of each roll, and i know the equation for the bending moment depending on the total curvature giving to make the wire straight.

Included is a Mathcad file with a short explanation on how the equations are formulated. I have a bigger file with all the details but that will require a lot of translation for me. I also have some literature on wire straighteners if anybody is interested.

Sorry for my English many thanks in advance,

Sander

1_Mathcad-question.zip

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-MFra-

21-Topaz II

Hi,

the curvature equation in your worksheet, is not correct. Instead it should be: The reciprocal of the radius of curvature is equal to the ratio between the second derivative and the square root ... Also you should deepen the study of the argument if you want to understand how to plot the bending momentum graph.

S

snadur

Author

1-Visitor

Thank you that was a mistake.

I know how to plot the bending moment for a three point bend, only not for repeating bends like with a wire straightener.

I could calculate every bend a
three rollers separately and make a graph myself, but it would be nice if i can have it in equation form and make Mathcad plot a graph like below.

I also know how to plot the curvature for a simple function, only not for a difficult function where there are two different functions, depending on the value of x.

If anyone has any idea how to do this, many thanks.

I just started engineering school and this elastic-plastic bending theory was probably not the best idea to choose as a project . It seems very complicated, especially in wire straighteners with multiple bends.