Hollow die are more used in soft alloy industry.
I worked for 22 years extruding in soft alloy
everything from automotive to carpet trim to
very complex hollows shapes. The strongest
alloy they use is 6061.
It is the equivalent of an adult Play Doh machine
It is a extrusion press that heats the aluminum
billets in 3 different diameters 22'' , 25'' and 29''
in lengths up to 72'' long an average of 750 degrees.
The tooling in which I'm in charge of is heated in die
boxes to 850 degrees. The extrusion press then pushes
the billet thru the tooling to make what ever shape
the customer wants. So the 2 gun shapes and the AR
bottom extrudes to a length of about 100' long.
After all our process's including ultra sonic testing
it goes to the customer where it is machined down
to their specs then cut to size.
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