MINERAL INSULATED CABLE FOR DOWNHOLE SENSORS

• US 20110224907A1
• Filed: 03/11/2010
• Published: 09/15/2011
• Est. Priority Date: 03/11/2010
• Status: Abandoned Application

• Current Assignee: Petrospec Engineering Ltd.
• Original Assignee: Petrospec Engineering Ltd.
• Inventors: Chalifoux, Gerald
• Application Number:
  US12/722,444
• Publication Number:
  US 20110224907A1
• Time in Patent Office: Days
• US Class Current: 702/11
• CPC Class Codes: E21B 47/06 Measuring temperature or pressure
• CPC Class Codes: G01K 7/02 using thermoelectric elements, e.g. thermocouples

Abstract

An apparatus for measuring downhole pressure includes a plurality of conductors within a mineral insulated cable, a pressure sensor attached to at least two of the conductors, and a thermocouple embedded in the mineral insulated cable. The pressure sensor generates a signal that is dependent upon pressure. The thermocouple is rated for temperatures greater than 150° C. The thermocouple generates a signal that is dependent upon temperature.

Claims

1. An apparatus for measuring downhole temperature and pressure, comprising:

a mineral insulated cable containing a plurality of conductors;

a pressure sensor attached to at least two of the conductors, the pressure sensor generating a signal that is dependent upon pressure;

a thermocouple embedded in the mineral insulated cable, the thermocouple comprising two of the plurality of conductors and generating a signal that is dependent upon temperature.

2. The apparatus of claim 1, wherein the pressure sensor is generates a signal that is dependent upon temperature and pressure.

3. The apparatus of claim 2, further comprising a processor connected to the conductors for calculating pressure based on the signal from the thermocouple and the signal from the pressure sensor.

4. The apparatus of claim 2, wherein the pressure sensor is a piezometer.

5. A method of measuring downhole temperature and pressure, comprising the steps of:

providing a mineral insulated cable, comprising;

a plurality of conductors within a mineral-insulated cable;

a pressure sensor attached to at least two of the conductors, the pressure sensor generating a signal that is dependent upon pressure;

a thermocouple embedded in the mineral insulated cable, the thermocouple generating a signal that is dependent upon temperature;

injecting the mineral insulated cable into a well; and

measuring the temperature and pressure in the well.

6. The method of claim 5, wherein the pressure sensor is generates a signal that is dependent upon temperature and pressure.

7. The method of claim 6, further comprising the step of calculating pressure based on the signal from the thermocouple and the signal from the pressure sensor.

8. The method of claim 6, wherein the pressure sensor is a piezometer.