Logging-While-Drilling proVISION* Tool


lwd_mrt6The 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.


• 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 (%)

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