How Does This Forge Work?

calstar

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Not a hobby forge but I came across this pic of a forge located in France, no info where I got the pic, anyone know anything about it, hows the cylinder heated, etc ? I guess the chain rotates the mandrel(?) and cylinder at the same time, then the "hammer" strikes, rotate, strike, rotate... and so on.

Thanks, Brian

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here's the same pic with a guy to show the size
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I suspect that the cylinder is heated elsewhere in a separate process then move into position for shaping. I think you're right about the chains turning the work. That is one massive piece of equipment.
 
That is correct. That is a rotary forge. There are a pair of chains to support and rotate the work. It usually starts out as a much smaller, but much thicker and shorter ring from another process. It expands and stretches as it is hammered. It's a skilled operation. Also one that typically requires multiple heats. I have had rings done in that process before, as it is cheaper and much less wasteful than a solid being cored. Makes for some tough material as well.


Brings to mind (not to hijack the thread) the mind bending question: Is a circle a polygon? Your proof please. :)
 
Thanks for the photos. I like watching the big machines at work. I have watched forging videos before. You are right the chain/link-belt is to rotate the mandrel. I hate to see the oven they use to keep that part hot. It would be interesting to see the machine setup to finish that part. That would take one king size boring bar to finish the inside diameter not to mention a mandrel to turn the outside.

Again thank you,
 
Thanks for the photos. I like watching the big machines at work. I have watched forging videos before. You are right the chain/link-belt is to rotate the mandrel. I hate to see the oven they use to keep that part hot. It would be interesting to see the machine setup to finish that part. That would take one king size boring bar to finish the inside diameter not to mention a mandrel to turn the outside.

Again thank you,
When I worked at Ladish in the sixties they had ovens that could have heated several of those at once.
 
That is impressive, reminds me of watching them forge cargo ship anchors when I was stationed out of the shipyards in Japan... Standing outside those doors on a cold winter night watching them at work feeling the heat roll out the was an awesome experience.
 
Brings to mind (not to hijack the thread) the mind bending question: Is a circle a polygon? Your proof please. :)
I would have to say no, it is not. A polygon is a closed plane figure bounded by a number of straight line segments If you break a circle up into a number of line segments, the segments are arcs, the center of which is the the center of the circle. As such, they are curved with a radius of curvature which remains unchanged, even as the number of segments approaches infinity. Therefore, the infinitely sided polygon still cannot meet the requirements of the polygon definition. Note that the perimeter of an infinite sided polygon equals the circumference of a circumscribed circle as shown below.
Polygon into Circle.JPG

Of course in practical terms, who cares? My CAM software is very comfortable with generating curves by straight line interpolation.
 
They are still doing a saddling operation. Rings that size are normally roll forged vertically to keep them from bending under their own weight.

It is still a polygon, but that won't make too much of a difference to the vertical lathe that will end up turning it.
 
Brings to mind (not to hijack the thread) the mind bending question: Is a circle a polygon? Your proof please. :)[/QUOTE]


Mathematician or Machinist ??

Lathe it is a circle

Mill it is a polygon unless use RT then it is Lathe
 
What if you hold the part in a collet in the mill spindle, with a bit in the vise?

Wow that is one big forge and one big ring.
 
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