Determining fluid pressure

Patent metadata

Field	Value
Publication number	US-9260959-B2
Application number	US-201314102236-A
Country	US
Kind code	B2
Filing date	Dec 10, 2013
Priority date	Feb 17, 2010
Publication date	Feb 16, 2016
Grant date	Feb 16, 2016

Abstract

A wellbore fluid pressure measurement system includes a densometer adapted to measure a fluid density of a fluid flowing in a tubing system; and a monitoring unit communicably coupled to the densometer. The monitoring unit is adapted to receive a plurality of values representative of the fluid density from the densometer and includes a memory adapted to store the plurality of values representative of the fluid density; and one or more processors operable to execute a fluid pressure measurement module. The module is operable when executed to determine a fluid pressure of the fluid based on at least a portion of the values representative of the fluid density.

First claim

What is claimed is:

1. A computer-implemented method of determining a wellbore fluid pressure, the method comprising:
receiving, at a computer, a signal from a densometer representative of a density of a fluid flowing through a wellbore, the fluid comprising a slurry having a fluid component and a solid component;
determining, by the computer, a fluid pressure of the fluid based at least in part on the signal;
empirically scaling the signal representative of the fluid density to determine the fluid pressure of the fluid by scaling the signal representative of the fluid density as a function of the fluid density and one or more empirically derived constants that are determined based at least in part on a combination of the densometer and a pressure transducer;
quantitatively scaling the signal representative of the fluid density to determine the fluid pressure of the fluid; and
initiating a signal that controls one or more components of a wellsite assembly installed at the wellbore to effect a remedial action to inhibit an overpressure condition, based at least in part on a determination that the determined fluid pressure exceeds a predefined pressure.

2. The computer-implemented method of claim 1 , wherein the signal comprises a plurality of values representative of the density of the fluid, and
determining, by the computer, a fluid pressure of the fluid based at least in part on the signal comprises determining, by the computer, a fluid pressure of the fluid based on at least a portion of the values representative of the density of the fluid.

3. The computer-implemented method of claim 1 , further comprising correcting the signal representative of the fluid density based on a concentration of the solid component in the slurry.

4. The computer-implemented method of claim 3 , wherein correcting the signal representative of the fluid density based on a concentration of the solid component in the slurry comprises correcting the signal representative of the fluid density based on the equation

ρ
fluid

=

C
prop

⁡

[

ρ
slurry

⁡

(

1

ρ
prop

+

1

C
prop

)

-
1

]

where ρ fluid is the corrected signal representative of the fluid density; C prop is the concentration of the solid component in the slurry in lbs of solid per gallon of fluid; ρ prop is an absolute density of the solid component in the slurry; and ρ slurry is a density of the fluid.

5. The computer-implemented method of claim 1 , further comprising:
comparing the determined fluid pressure to the predefined pressure; and
determining that the fluid pressure exceeds the predefined pressure.

6. The computer-implemented method of claim 1 , wherein initiating a remedial action comprises generating a warning, in real-time, to shut down or throttle pumping equipment.

7. The computer-implemented method of claim 1 , further comprising determining the fluid pressure from the equation:
P=C 1 *ρ fluid 3 −C 2 ,

where P is the empirically corrected fluid pressure value; ρ fluid is the density values of the fluid; and C 1 and C 2 are the one or more empirically derived constants.

8. The computer-implemented method of claim 1 , further comprising:
determining the one or more empirically derived constants based on a curve fit process of the density values to measured fluid pressure values.

9. The computer-implemented method of claim 8 , wherein the curve fit process is performed within a fluid pressure range measurable by the pressure transducer.

10. A computer program product for determining a wellbore fluid pressure, the computer program product comprising computer readable instructions embodied on non-transitory tangible media that are operable when executed by a processor to perform operations comprising:
receiving a signal from a densometer representative of a density of a fluid flowing through a wellbore, the fluid comprising a slurry having a fluid component and a solid component;
determining a fluid pressure of the fluid based at least in part on the signal;
empirically scaling the signal representative of the fluid density to determine the fluid pressure of the fluid by scaling the signal representative of the fluid density as a function of the fluid density and one or more empirically derived constants that are determined based at least in part on a combination of the densometer and a pressure transducer;
quantitatively scaling the signal representative of the fluid density to determine the fluid pressure of the fluid; and
initiating a signal that controls one or more components of a wellsite assembly installed at the wellbore to effect a remedial action to inhibit an overpressure condition, based at least in part on a determination that the determined fluid pressure exceeds a predefined pressure.

11. The computer program product of claim 10 , wherein the signal comprises a plurality of values representative of the density of the fluid, and
determining, by the computer, a fluid pressure of the fluid based at least in part on the signal comprises determining, by the computer, a fluid pressure of the fluid based on at least a portion of the values representative of the density of the fluid.

12. The computer program product of claim 10 , wherein the operations further comprise correcting the signal representative of the fluid density based on a concentration of the solid component in the slurry.

13. The computer program product of claim 12 , wherein correcting the signal representative of the fluid density based on a concentration of the solid component in the slurry comprises correcting the signal representative of the fluid density based on the equation

ρ
fluid

=

C
prop

⁡

[

ρ
slurry

⁡

(

1

ρ
prop

+

Assignees

• Halliburton Energy Services Inc

Inventors

• Beisel Joseph A
• Stephenson Stanley V

Classifications

• E21B47/06 Primary

  Measuring temperature or pressure · CPC title