Abstract: A wellhead system for petroleum producing wells comprises a “stack-down” casing hanger configuration. In this stack-down system, the hanger for each successively smaller diameter casing string is landed or “nested” within the hanger for the next larger casing string. This approach allows the pack-off for each casing hanger to be retrieved independently, thus allowing fluid communication to be established with any of the casing annuli after all of the casing strings and hangers have been installed. Thus the pressure in each annulus may be monitored while the well is in production mode.

Abstract: A well data monitoring system which enables annulus pressure and other well parameters to be monitored in the outer annuli of the well casing program without adding any pressure containing penetrations to the well system. This non-intrusive approach to monitoring pressure and other well parameters in the annuli preserves the pressure integrity of the well and maximizes the safety of the well. In the preferred embodiment an intelligent sensor interrogation system which can be located externally or internally of the pressure containing housing of the wellhead is capable of interrogating and receiving data signals from intelligent well data sensors which are exposed to well parameters within the various annuli of the well and wellhead program.

Abstract: A wellhead system for petroleum producing wells comprises a “stack-down” casing hanger configuration. In this stack-down system, the hanger for each successively smaller diameter casing string is landed or “nested” within the hanger for the next larger casing string. This approach allows the pack-off for each casing hanger to be retrieved independently, thus allowing fluid communication to be established with any of the casing annuli after all of the casing strings and hangers have been installed. Thus the pressure in each annulus may be monitored while the well is in production mode.

Abstract: A well data monitoring system which enables annulus pressure and other well parameters to be monitored in the outer annuli of the well casing program without adding any pressure containing penetrations to the well system. This non-intrusive approach to monitoring pressure and other well parameters in the annuli preserves the pressure integrity of the well and maximizes the safety of the well. In the preferred embodiment an intelligent sensor interrogation system which can be located externally or internally of the pressure containing housing of the wellhead is capable of interrogating and receiving data signals from intelligent well data sensors which are exposed to well parameters within the various annuli of the well and wellhead program.

Abstract: A protective cap (12) can be run onto and retrieved from a subsea wellhead (10) from a floating service vessel. Slidably mounted shear pins (32) in the cylindrical wall (14) of the protective cap (12) allow the cap to be attached by a downward push. Retrieval of the protective cap (12) involves an overpull on the drill string that is sufficient to shear the pins (32) in the cylindrical wall (14).

Abstract: An improved metal-to-metal seal packoff system for establishing a high pressure metallic barrier between concentric tubular elements, such as a wellhead housing and a casing hanger, including a seal element with a pair of annular metal sealing lips that are energized by the wedging force of an expander mandrel having a cross-sectional configuration resembling a tuning fork with depending legs.

Abstract: A well casing suspension system comprising a casing hanger assembly with an expandable, multiple shoulder, split load ring that is radially expanded into supporting position in a mating groove in a wellhead housing by contact with a previously installed annulus packoff.

Abstract: A well tool for running, landing and setting a casing hanger and a packoff in a wellhead housing, and pressure-testing the integrity of the packoff seal, all in a single trip into the well.