Butterfly, Butterfly (The Last Hurrah) Butterfly, Butterfly (The Last Hurrah) "Butterfly, Butterfly (The Last Hurrah)" is a song by A-ha, and their final recording before their second splitting on 4 December 2010. The song was sold digitally in Norway from July 5. It is included on "25", a compilation album released on July 19. Its world premiere was on June 14, 2010. The single entered the Norwegian single chart at #13 and reached #6 on the airplay chart soon after. It also charted at #66 in the World singles official top 100. Much like many of A-ha's early music videos (including that of "Take on
Butterfly valve installation, but pipelines containing butterfly valves cannot be 'pigged' for cleaning. The butterfly valve has been in use since the late 18th century. James Watt used a butterfly valve in his steam engine prototypes. With advances in material manufacturing and technology, butterfly valves could be made smaller and withstand more-extreme temperatures. After World War II, synthetic rubbers were used in the sealer members, allowing the butterfly valve to be used in many more industries. In 1969 James E. Hemphill patented an improvement to the butterfly valve, reducing the hydrodynamic torque needed to change the output of the valve. Butterfly valve