What describes the extrusion process for seamless tubes?

The extrusion process for seamless tubes involves forming a hot hollow billet that is squeezed through a die and mandrel. This method allows the manufacturers to produce tubes without seams, which enhances their strength and overall quality. During the process, the billet is heated to a malleable state and then forced through a die that shapes it into a tubular form. The presence of a mandrel inside the billet helps maintain the necessary inner diameter of the tube while the billet is being extruded.

This process is particularly advantageous because it eliminates welded seams, which are often points of weakness in metal tubing. It also provides the ability to create tubes with varying wall thicknesses and diameters, giving flexibility for various applications in industries such as automotive, aerospace, and manufacturing.

The other options present alternative methods of shaping metals or tubes but do not accurately describe the seamless extrusion process. For instance, shaping a hot solid billet into a tube or cutting from a solid piece does not achieve the seamless characteristic essential to the extrusion process being discussed.