Wellbore Tubular Length Determination Using Pulse-Echo Measurements

Patent metadata

Field	Value
Publication number	US-2016265351-A1
Application number	US-201315033539-A
Country	US
Kind code	A1
Filing date	Dec 23, 2013
Priority date	Dec 23, 2013
Publication date	Sep 15, 2016
Grant date	—

Abstract

Systems and methods are disclosed for obtaining distance-related wellbore parameters using pulse-echo measurements. For example, the depth of a wellbore may be computed and/or the length of a tubular string positioned in a wellbore may be determined.

First claim

1 . A method comprising:
transmitting a first fluid pulse along a wellbore using a first pulse generator; receiving the first fluid pulse at a first sensor positioned along the tubular; in response to the received first find pulse, transmitting a second thud pulse back along the wellbore to a second sensor using a second pulse generator positioned along the tubular; receiving the second fluid pulse at the second sensor; determining a total travel time for the first and second fluid pulses; and determining a length along the tubular based upon the total travel time.

2 . A method as defined in claim 1 , wherein the wellbore contains drilling or completion fluid.

3 . A method as defined in claim 1 , wherein the first pulse generator and second sensor are located:
at or adjacent to a surface location; or at a position along the tubular above the second pulse generator.

4 . A method as defined in claim 1 , wherein the tubular comprises at least one of coiled tubing, drill pipe or production pipe.

5 . A method as defined in claim 1 , wherein the tubular has been stretched.

6 . A method as defined in claim 1 , wherein the determining the total travel time comprises accounting for a processing delay.

7 . A method as defined in claim 1 , wherein determining the total travel time comprises accounting for density variations in the fluid due to hydrostatic pressure at various depths.

8 . A method as defined in claim 7 , further comprising determining an average velocity of the first and second fluid pulses using the density variations in the fluid.

9 . A method as defined in claim 1 , wherein determining the length comprises using an equation represented by:
l =( v×Δt l )/2

10 . A system comprising processing circuitry to implement the method in claim 1 .

11 . A method for determining downhole tubular length, the method comprising:
transmitting a first fluid pulse along downhole casing using a pulse generator located at a surface; receiving the first fluid pulse at a reflection point along an inner diameter of the casing, whereby a second fluid pulse is reflected back toward the surface; receiving the second fluid pulse; determining a total travel time of the first and second fluid pulses; and determining a length of a casing using the total travel time.

12 . A method as defined in claim 11 , wherein the reflection point is the bottom of the casing.

13 . A method as defined in claim 11 , wherein determining the total travel time comprises accounting for at least one of:
a processing delay; or density variations in the fluid along the wellbore.

Assignees

• Halliburton Energy Services Inc

Inventors

• Gajji Bhargav
• Purohit Ankit
• Pangu Ganesh Shriniwas
• Pujeri Keshav Parashuram

Classifications

• E21B47/095

  by detecting an acoustic anomalies, e.g. using mud-pressure pulses · CPC title

• E21B47/024

  of devices in the borehole (determining slope or direction of the borehole E21B47/022) · CPC title

• E21B47/04 Primary

  Measuring depth or liquid level · CPC title

• E21B47/18 Primary

  through the well fluid {, e.g. mud pressure pulse telemetry} · CPC title

• E21B49/00

  Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells · CPC title