PIPING

摘要

The invention relates to piping for use as a pyrolysis tube in a cracking furnace. The tube is formed such that it has at least one section whose centreline curves in three dimensions, to induce swirl flow in the tube. Preferably, the tube is formed as a helix, more preferably a low-amplitude helix. The invention also extends to various other uses of piping with low- amplitude helical geometry.