Centerfire Propagation Wave Resistivity

Centerfire Propagation Resistivity collar is designed to provide existing Tensor customers an easy upgrade from directional or directional-gamma services to LWD while minimizing the total cost of ownership. The fully retrievable probe-based directional MWD module is situated above the resistivity collar. Use of a wet connect communication assembly means the collar can be removed from the tool string with the logging data downloaded at the surface even if the rest of the bottom hole assembly (BHA) remains stuck in hole.

High Temperature Geosteering Application for Increased Accuracy and Reliability

The Centerfire TM Propagation Resistivity is designed for high temperature Geosteering applications with increased accuracy and reliability. Rated to 175°C (347°F), it is the system of choice for hot-hole applications and available in three standard sizes – 4.75 in., 6.91 in. and 8.25 in. The collar uses an industry standard transmitter-receiver design with 19 in. and 41 in. antenna spacings, measuring both phase difference and attenuation.

The collar provides eight different depths of investigation (DOI) borehole compensated resistivities. Any combination of these can be transmitted in real-time. The deep-reading 400 kHz measurements from the 41 in. antenna spacings are ideal for geosteering and bed-boundary detection when combined with the shallower reading 2 MHz measurements from the 19 in. antenna spacings. The 2 MHz measurements also offer excellent vertical resolution for thin bed identification.

Wear parts are easily serviced and all electronics are accessible below hatch covers to allow drop-in replacement, where required. Calibration by way of air hang can be completed in less than one hour.

Proven Performance

With a history of successful deployments, including notable multi-lateral applications in China and Russia and offshore deployments in Mexico, the Centerfire system enables independent service companies to expand their service options, allowing them to compete in technologically advanced markets, with a cost-effective, proven platform.