squashing tubing into an ellipse
squashing tubing into an ellipse
(OP)
If a thin walled metal round tube is squashed along its entire length will the final yielded shape be an ellipse (new "diameter/smaller axis" limited to no less than 0.75D)?





RE: squashing tubing into an ellipse
Luck is a difficult thing to verify and therefore should be tested often. - Me
RE: squashing tubing into an ellipse
TTFN
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RE: squashing tubing into an ellipse
Feed it through shaped rollers or use shaped dies in a press.
Chances are you will end up with an oval more than a true ellipse.
RE: squashing tubing into an ellipse
The reason is that 4 or 6 plastic hinges will form a mechanism and prevent the rest of the metal from yielding.
Cheers
Greg Locock
SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: squashing tubing into an ellipse
There are also some oval cross section tubes available from sources like this: http:/
Good luck.
RE: squashing tubing into an ellipse
Depending on the tube size just sticking a small sample length in a vice should give you a good idea what you are likely to get with flat forming, capping and filling the tube with sand will give a better result on a shaped form tool. If it is seemed tube the placement of the weld will have a fairly major impact.
As with so many things in engineering small increases in accuracy result in large increases in cost, how accurate does it need to be?
RE: squashing tubing into an ellipse
RE: squashing tubing into an ellipse
I know some tube density meters have an "elliptical"/"oval"/"flattened" tube which is nominally 1" bore.
The reasons? it gives the tube a preferred bending moment when it is vibrated and it is to minimise the pressure effects on the resonant frequency...
JMW
www.ViscoAnalyser.com
RE: squashing tubing into an ellipse
http://www.boschertusa.com/bendopc300.html