The first step in the production sequence is called heated pressing, and it is followed by extrusion, which is the second step in the production sequence. An extruded aluminum tube is a specific kind of aluminum tubing that is produced after this step. Both of these names are used to refer to the same thing, but in different contexts. Pipes that are made of aluminum are never referred to as "welded pipes," which is a term that is typically used in reference to pipes made of steel. This is becaus...