Flat pattern of a pipe

[Anonymous]

Hello, 

I have a 12 inch pipe which needs to be welded to a 18 inch pipe elbow. I want to flatten the 12 inch pipe so i can plot on a 1:1 scale to help trace the cut. It sounds simple but every way I tried it came out with inconsistent dimensions. 

The 12 inch pipe has an outer diameter of 323.90mm which should give ~1017mm when flatened but it always comes out short. I even tried on Solidworks and it came out with the same result and i cant figure it out why

[TheCADWhisperer]

This has been covered here several times in the past - a search might turn up the technique.

This guy https://www.youtube.com/channel/UCF7zEkelSRiHB1rOnspaBgQ also has a video on the technique.

[CCarreiras · Accepted solution]

Hi!

Flatten a tube is not the same thing as bending, so you have to change some parameters to obtain better results.

Go to Sheet Metal Defaults and in Default Kfactor change the KFactor to 1 (instead of the 0,4) and you can also tweak the Rip gap (by default, the rip gap is equal to the thickness) so it's better to decrease this value to 1mm or less.

Doing this i believe you will get better results.

[Anonymous]

Thanks a lot, that fixed it. 

[CCarreiras]

Tens de vêr ainda a questão do bisel... se queres as medidas com o corte biselado ou não. Dependendo disso, ainda terá de ser feito aí uns retoques.