Systems and methods for measuring forces acting on a downhole tool
AssigneeSchlumberger Technology Corporation
InventorChe-Keung Lawrence Lee
Life of this patent
Estimating the term…
Abstract
An apparatus for measuring forces acting on a downhole tool is provided. The apparatus can include an annular body having an axial bore formed therethrough. A first fluid can be disposed within the bore. An annular sleeve can be disposed proximate an inner surface of the body. An annular chamber can be formed between the body and the sleeve, and a second fluid can be disposed within the chamber. A sensor can be coupled to the sleeve to measure a strain placed on the sleeve by a pressure differential between the first and second fluids. A pressure of the first fluid in the bore can be determined from the strain.
Claims20
An apparatus for measuring forces acting on a downhole tool, comprising:
- an annular body having an axial bore formed therethrough, wherein a first fluid is disposed within the bore;
- an annular sleeve disposed proximate an inner surface of the body;
- an annular chamber formed between the body and the sleeve;
- a second fluid disposed within the chamber;
- a first sensor coupled to the sleeve to measure a strain placed on the sleeve by a pressure differential between the first and second fluids, wherein a pressure of the first fluid in the bore is determined from the strain;
- a cover disposed proximate an outer surface of the body, wherein a second chamber is formed between the body and the cover, wherein a third fluid is disposed with the second chamber;
- and
- a second sensor coupled to the sleeve to measure a strain placed on the sleeve by a pressure differential between the first fluid and the second fluid.
An apparatus for measuring forces acting on a downhole tool, comprising:
- an annular body having an axial bore formed therethrough, wherein a first fluid is disposed within the bore;
- a sleeve disposed proximate an inner surface of the body, wherein a first chamber is formed between the body and the sleeve, and wherein a second fluid is disposed within the first chamber;
- a cover disposed proximate an outer surface of the body, wherein a second chamber is formed between the body and the cover, wherein a third fluid is disposed within the second chamber, and wherein a pressure differential between the second and third fluids is less than 1000 kPa;
- a first sensor coupled to a load bearing portion of the body between the first and second chambers to measure a strain placed on the body by an axial load on the body, wherein the axial load is determined from the strain;
- and
- a hole formed through the load bearing portion of the body to place the first chamber in fluid communication with the second chamber to enable the pressures of the second and third fluids to equalize.
A method for measuring forces acting on a downhole tool, comprising:
- running the downhole tool into a wellbore, the downhole tool comprising:
- an annular body having an axial bore formed therethrough, wherein a first fluid is disposed within the bore;
- a sleeve disposed proximate an inner surface of the body, wherein a first chamber is formed between the body and the sleeve, and wherein a second fluid is disposed within the first chamber;
- a cover disposed proximate an outer surface of the body, wherein a second chamber is formed between the body and the cover, wherein a third fluid is disposed within the second chamber, and wherein a pressure differential between the second and third fluids is less than 1000 kPa;
- and
- measuring a strain on the sleeve with a sensor coupled thereto, wherein the strain is caused by a pressure differential between the first and second fluids, and wherein a pressure of the first fluid is determined from the strain.
Dependencies are inferred from the claim text.