In the early days of floating drilling it became apparent that a pivot point at the lower end of the marine riser next to the BOP stack was needed to reduce stress and fatigue in the marine riser. As water depths increased a new devise was needed. Lockheed Propulsion invented a pivot devise consisting of concentric spherical rings of steel separated and adhered to by elastomeric material that could withstand very large tensions and pressures. In 1976 the first subsea drilling “Flex Joint”TM was designed and manufactured by Oil States and used on a SEDCO rig. Following its successes in drilling, the technology was used in 1984 for the TLP tendons on the North Sea Conoco Hutton platform. In 1994 Shell used the device with steel catenary risers (SCR) on floating production systems. Since that time there has been over 700 versions of the Flex JointTM used in the offshore oil and gas industry.
Recognizing the pioneering efforts of the following individuals and organizations that contributed to this technology: Mark A. Childers, Mike Hogan, Frans Kopp, Craig Lang, Carl Langner, Charles Moses, Charles Reinhardt, Earl Shanks and Jim Slade Conoco (now ConocoPhillips), Kingsnorth Marine Drilling, Lockheed Propulsion, ODECO (now Diamond Offshore Drilling Inc.), Oil States (now Oil States International, Inc.), SEDCO (now Transocean), and Shell