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Installations with Oxy Fuel Direct Flame Impingement heating (DFI) are since some years in operation at ThyssenKrupp Steel's plants in Finnentrop and Bruckhausen, Germany. At both sites, this technology has resulted in about 30% increased throughput capacity in the galvanizing and aluminizing lines without any extension of the furnace length. In addition to the production capacity increase, this Direct Flame Impingement oxyfuel technology has reduced the specific fuel consumption and NOx emissions. In galvanizing the results also include improved zinc adhesion and surface appearance; this is due to DFI's pre-cleaning and pre-oxidising properties, leaving both strip and furnace rolls cleaner than before. A further result is the short installation time; a line stop of four days has been sufficient. DFI is a compact technology with high heat transfer which provides enhanced operation in strip processing lines such as galvanizing. The DFI solution also has a higher total energy efficiency compared to for example inductive heating. It is important to note that the system does not create an oxidation problem, for example, practical experience with pre-heating up to 400 °C shows no problems. The main benefits include: higher heat transfer (3-4 times the process in use) resulting in increased production capacity; low fuel consumption due to small flue gas volume; ability to use high power input in limited furnace volume; compact and powerful unit for easy retrofit; heating and cleaning in one operation; options to modify surface conditions. The paper describes the results achieved at ThyssenKrupp Steel at Finnentrop and Bruckhausen, and why this technology was chosen at those plants. At Finnentrop the capacity increased from 82 to 109 t/h, and at Bruckhausen from 70 to 90 t/h. Among the results could be mentioned that DFI Oxyfuel made it possible for ThyssenKrupp to pre-oxidise steel strips in a precise and controlled manner. In addition to the installations at ThyssenKrupp, DFI has also been employed at strip annealing lines, for example by Outokumpu for stainless steel in Sweden.