In the 1960s, when Honda won its first Formula 1 race, the Japanese automotive industry entered a new era. This study attempted to accurately reproduce and analyze the process of formation of the exhaust pipe of the winning RA272 engine, using the waza (skills) employed in its fashioning, which have been handed down by its makers. This analysis showed that the manual bending method, used to create the RA272 exhaust pipe, which was filled with sand and bent while being flame-heated, enabled the achievement of a continuous curve with a high bending limit, without the use of figures or molds, and was superior to the mechanical bending method of that time, from the standpoint of the degree of freedom of the layout, as well as that of speed of production. Study of the skills employed by sheet metal specialists at the moment of pipe bending has provided information on the bending temperature and point at which bending is initiated, which is important in elucidating the pipe production technique. The fact that the pipe displays lower residual stress from bending and that the microstructure of the material remains stable, even at exhaust temperatures of 700 °C to 900 °C, has also provided useful information on the pipe’s shape stability and mechanical strength.
Article of Honda R&D Technical Review Vol.19 No.2 (12 - 19)