Log while drilling an extreme high-temperature, high-pressure well in the Gulf of Mexico. Weatherford’s hostile-environment PrecisionLWD™ logging while drilling system successfully provided data for the unlogged hole section and began drilling operations at approximately 24,000 ft (7,315 m). At the time, the tool was recording a temperature of 315°F (157°C). MFR™ multi-frequency resistivity sensor data were used to predict pore pressure, enabling the operator to push the casing point to a greater than expected depth. HAGR™ high-temperature azimuthal gamma-ray sensor data helped determine lithology changes and were used with seismic data for better correlation. BAP™ bore and annular pressure sensor data accurately measured equivalent circulating density to help minimize mud losses. BAP data were also valuable in monitoring the downhole turbine pressure drop. IDS™ integrated directional sonde provided directional and toolface measurements. After five days, the circulating temperature reached 353°F (178°C), and the MFR sensor failed to respond. The system continued to transmit data from all other sensors and operated for an additional nine days until the circulating temperature reached 371°F (188°C).

Value to Client

This maximum temperature is believed to be a record for the Gulf of Mexico. The reliable acquisition and surface transmission of LWD data were critical to the project’s successful execution.

The PrecisionLWD system is designed specifically for deep well and hightemperature/ high-pressure drilling environments. The system transmits real-time directional data, gamma ray data, bore and annular pressure data, downhole shock/vibration data, and all petrophysical measurements. It is rated to an operating temperature of 356°F (180°C), a survival temperature of 392°F (200°C), and a survival pressure of 30,000 psi (207 MPa).

Location
Deep shelf, Gulf of Mexico shelf

Total Runs 1

Operating Hours 2,350

Circulating Hours 1,512

Maximum Temperature 371°F (188°C)

Maximum Pressure 29,000+ psi (200+ MPa)

Operating Hours 453

Circulating Hours 348

Products/Services

• LWD service
• PrecisionLWD system with MFR, BAP, HAGR, and IDS sensors