Fluid Formed Aluminium Tubing

[grippy]

Recently came across this tubular section

http://www.pinkbike.com/modules/photo/?op=view&image=107218

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used in bicycle frame manufacture... and would appreciate any info or comments on "fluid formed" aluminium tubes in general (or directions to said info).

For anyone interested in commenting on specifics, the "infotorial" from this particular frame manufacturer claims "...a crease is formed as part of the fluid forming process... we simply decided to create a moulded weld appearance out of that crease... the gusseting effect of this tube shape is significantly stronger than a standard round or ovalised tube..." any and all comments/opinions welcome.

Cheers

 

[TVP]

I presume that fluid forming is referring to the process usually known as hydroforming. Tube hydroforming uses a fluid to pressurize the inside of a tube so that it can deform (both locally and globally) and occupy the shape of the die cavity. Geometry and thickness can be modified by this process. In this particular case, the second moment of inertia of the tube can be increased by changing the shape from that of a round or oval tube.

 

[CoryPad]

Based on the word description, and the image, I agree that the process is hydroforming. However, I don't understand why there is a seam along the pipe.


Regards,

Cory

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