Year Inducted: 2000
H.L. "Duke" Zinkgraf
A prolific inventor, Duke Zinkgraf provided practical solutions to the problems of dynamic positioning (DP) of offshore rigs, including the world’s first DP coring vessel, the Eureka. He was intimately involved in the design and construction of the SEDCO 445, the world’s first DP vessel used to drill exploratory wells with a riser and subsea BOP. He was also actively involved in building the SEDCO 709, the world’s first DP semi-submersible rig. Working for The Baylor Company, Zinkgraf was instrumental in adapting the eddy current current brake to the drilling industry, and was the first to convert rig power from AC to DC to provide higher efficiency. He also assisted Varco with the design of the top drive system.