Logging-While-Drilling proVISION* Tool
Description
The Schlumberger Logging-While-Drilling-proVISION (LWD-proVISION) tool performs magnetic resonance measurements in the borehole and transmits them in real-time to the surface. Magnetic resonance provides parameters that are not measured by traditional LWD tools such as permeability, free- and bound fluid-volume, type of fluid, and mineralogy-independent porosity. These allow for an accurate characterization of the formation without use of radioactive sources as well as direct detection of the presence of hydrates.
Applications
• Determination of free vs. bound fluid volume
• Detection of hydrates
• Measurement of mineralogy-independent porosity
• Fluid identification
Tool Specifications
| Temperature rating: | 300° F (149° C) |
| Pressure rating: | 20 kpsi (138 MPa) |
| Tool make-up length: | 39 ft (11.9 m) |
| Tool weight: | 3,900 lbs (1,771 kg) |
| API nominal collar outside diameter: | 6.75 in (17 cm) |
| Maximum outside diameter: | 7.75 to 10.375 in (20 to 26.4 cm) |
| Minimum bit size: | 8.5 in (26 cm) |
| Maximum bit size: | 10.625 in (27 cm) |
| Flow range: | 250-800 gpm |
| Pressure drop coeffecient (C)*: | 30,000 |
| Maximum curvature – sliding: | 16 deg/100 ft (16 deg/31 m) |
| Maximum rotary torque: | 16,000 ft-lbf (4,877 m-lbf) |
| Minimum operating RPM: | 0 rpm |
| Uphole connection: | 5-1/2 FH box |
| Downhole connection: | 5-1/2 FH box |
| (*) pressure drop = [mudweight in ppg] x [flow in gpm]²/C |
Measurement Specifications
| Range: | 0-100 pu |
| Vertical resolution: | 3.9 ft @ 100 ft /hr (1.19 m @ 30 m/hr) |
| Porosity accuracy: | ±1 pu or 5% (whichever is greater) |
Major Outputs
| BFV: | Bound Fluid Volume (%) |
| FFV: | Free Fluid Volume (%) |
| MRP: | Magnetic Resonance Porosity (%) |
| T2: | T2 Distribution (%) |
| T2LM: | T2 Logarithmic Mean (%) |
* ®trademark of Schlumberger