Which type of pipe is produced by piercing a billet?

The production of seamless pipe involves a process where a solid billet is heated and then pierced to create a hollow tube. This is typically done using a method known as rotary piercing, where the billet is rotated and forced through a smaller diameter roll, creating a long hollow pipe without seams or welds. This method results in pipes that have enhanced strength and integrity due to the uninterrupted structure of the material. Seamless pipes are commonly used in applications requiring high durability and resistance to pressure and corrosion, such as in the oil and gas industry.

Welded pipes, on the other hand, are created by rolling a piece of metal and then welding the edges together, which introduces a seam that seamless pipes do not have. Similarly, threaded pipes are typically processed from either welded or seamless pipes that are subsequently cut to have threads on their ends for connecting with other fittings. Composite pipes are made from multiple materials layered together, which is a different methodology altogether. Thus, the correct identification of the type of pipe produced by piercing a billet is seamless pipe.