/community-hubs/valves-actuators-regulators/b/valves-weblog/posts/butterfly-valve-for-diverse-throttling-and-on-off-applicationsReferences to the use of butterfly valves date back to James Watt, who : …made use of a butterfly valve in his steam engine, and the first Mercedes car built around 1901 introduced a butterfly valve in the fuel intake linked to the accelerator pedalen-USTelligent Community 13