Well monitoring
AssigneeExpro North Sea Limited
InventorsAlexandra Vasil'evna Rogacheva, Robert Charles Bromwich, Bridget Mary Weston, Steven Martin Hudson
Life of this patent
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Abstract
Downhole water level detecting apparatus for detecting the level of water in a formation in the region of a well installation. The detecting apparatus includes a transmitter for applying electrical signals to a signaling loop at a first location. The signaling loop includes a downhole metallic structure of the well installation and an earth return. The detecting apparatus also includes a detector for monitoring electrical signals in the signaling loop, and an evaluation unit arranged for determining a level of water in the formation relative to the downhole metallic structure in dependence on the monitored signals.
Claims17
A well installation for detecting a downhole location level of a water bearing region (W) in a formation associated with a well, the well installation comprising:
- tubing comprising a product extraction section and an extension portion, the extension portion disposed at a depth in the well beyond the product extraction section, and the extension portion is configured to provide a distributed connection to Earth;
- a transmitter configured to apply signals to the tubing;
- an evaluation unit;
- and
- a receiver configured to receive said signals from the tubing, said signals having a strength, and to communicate the received signals to the evaluation unit;
- wherein the extension portion is configured such that an impedance experienced by the signals conducted within the extension portion varies as a function of the downhole location level of the water bearing region (W), and the strength of the signals received by the receiver varies as a function of the impedance experienced by the signals conducted within the extension portion;
- and
- wherein the evaluation unit is configured to detect the downhole location level of the water bearing region (W) based on the strength of the signals received by the receiver.
A method for detecting a downhole location level of a water bearing region (W) in a formation associated with a well, comprising:
- providing a well installation comprising tubing having a product extraction section and an extension portion, the extension portion being disposed at a depth within the well beyond the product extraction section, and the extension portion is configured to provide a distributed connection to Earth;
- applying signals to the tubing and receiving the applied signals from the tubing;
- wherein the extension portion is configured such that an impedance experienced by the applied signals conducted within the extension portion varies as a function of the downhole location level of the water bearing region (W), and a strength of the received signals varies as a function of the impedance experienced by the applied signals conducted within the extension portion;
- and
- detecting the downhole location level of the water bearing region (W) in the formation associated with the well based on the strength of the received signals.
A surface unit for detecting a downhole location level of a water bearing region (W) in a formation associated with a well, which well includes a well head and tubing extending downhole from the well head, the tubing comprising a product extraction section and an extension portion, the extension portion disposed at a depth in the well beyond the product extraction section, and the extension portion is configured to provide a distributed connection to Earth, the surface unit comprising:
- an evaluation unit;
- and
- a receiver configured to receive signals from applied to the tubing and communicate the received signals to the evaluation unit, wherein an impedance experienced by the applied signals conducted within the extension portion varies as a function of the downhole location level of the water bearing region (W), and a strength of the received signals varies as a function of the impedance experienced by the applied signals conducted within the extension portion;
- wherein the evaluation unit is configured to detect the downhole location level of the water bearing region (W) in the formation based on the strength of the received signals.
Dependencies are inferred from the claim text.