Method and apparatus for NMR sensor with loop-gap resonator
AssigneeBaker Hughes Incorporated
InventorsThomas Kruspe, Martin Blanz, Peter Rottengatter
Life of this patent
Estimating the term…
Abstract
A loop-gap resonator for providing an excitation pulse in a down hole nuclear magnetic resonating (NMR) tool for determining a parameter of interest in a formation adjacent a borehole. The loop-gap resonator is constructed having one or more capacitive gaps formed in a nonmagnetic conductive loop. The loop-gap resonator may be deployed down a bore in a measurement while drilling (MWD) configuration or in a wire line configuration. The MWD configuration may utilize a non-rotating sleeve rotationally associated with the drill string.
Claims24
A nuclear magnetic resonance (NMR) tool for determining a parameter of interest for a formation surrounding a borehole, comprising:
- a loop gap resonator associated with the NMR tool
- for at least one of:
- transmitting an RF magnetic field into a region of interest in the formation and receiving a NMR signal from the formation.
A method for determining a parameter of interest for a formation surrounding a borehole, comprising:
- traversing a bore hole formed in the formation with a nuclear magnetic resonance (NMR) tool, the tool having a loop gap resonator for at least one of:
- transmitting an RF magnetic field into a region of interest in the formation and receiving a NMR signal from the formation.
15 The method of claim 13 wherein the loop gap resonator is made of a conductive nonmagnetic material.
18 The method of claim 13, further comprising:
- connecting a capacitor between the longitudinal gap in the loop gap member with a pair of electrically insulated wires.
The method of claim 18, wherein the capacitor comprises a variable capacitor connected across the wires, such that the variable capacitor can be adjusted to alter the resonant frequency of the loop gap resonator.
21 The method of claim 13, further comprising:
- a soft magnetic, flux-guiding material inside the loop gap resonator.
Dependencies are inferred from the claim text.