Cracking tube having helical fins

• Main Authors: HAMADA KAORU, OTSUBO KENJI, INUI MASAHIRO
• Format: Patent
• Language: English
• Published: 18.05.2006
• Subjects: BLASTING; CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; CHEMISTRY; CRACKING HYDROCARBON OILS; DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OFGENERAL APPLICATION; DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS,IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KINDOF FURNACE; FUELS; FURNACES; HEAT EXCHANGE IN GENERAL; HEATING; KILNS; LIGHTING; LUBRICANTS; MECHANICAL ENGINEERING; METALLURGY; MINERAL WAXES; MIXING, e.g. DISSOLVING, EMULSIFYING, DISPERSING; OVENS; PEAT; PERFORMING OPERATIONS; PETROLEUM, GAS OR COKE INDUSTRIES; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVEHYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, ORGASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; RETORTS; TECHNICAL GASES CONTAINING CARBON MONOXIDE; THEIR RELEVANT APPARATUS; TRANSPORTING; WEAPONS

A cracking tube ( 50 ) for use in thermal cracking furnaces for producing ethylene or the like has fins ( 1 ) formed on an inner surface thereof and inclined with respect to an axis of the tube for stirring a fluid inside the tube. The fins are arranged discretely on one or a plurality of helical loci, and the tube inner surface has regions (ZB) wherein no fins are present over the entire axial length of the tube from one axial end of the tube to the other axial end thereof.