Method and device to measure perforation tunnel dimensions
First Claim
1. A method of logging a perforation tunnel and associated features of the perforation tunnel, comprising:
- a) locating a logging device including an ultrasonic transducer into a well, the well having a casing, the ultrasonic transducer having a focal point that is a distance from the ultrasonic transducer so as to be behind the inner face of the casing;
b) projecting an ultrasonic signal from the ultrasonic transducer;
c) detecting a reflection of the ultrasonic signal from an internal portion of the perforation tunnel, the perforation tunnel extending through the casing and into formation;
d) measuring a transit time between transmission and reception of the ultrasonic signal;
e) determining a position of the ultrasonic transducer corresponding to the ultrasonic transmission and reception of the reflected signal;
f) repeating steps b)-e) multiple times and recording resultant data;
g) processing the resultant data with a computer and determining a dimension of the perforation tunnel; and
wherein the ultrasonic transducer is located a standoff distance from the wellbore casing at least one-third of a length of a minimum open tunnel length required to measure;
the standoff distance being so that reflections from the casing reverberate and substantially dissipate before a reflection from inside the perforation tunnel is received by the ultrasonic transducer.
1 Assignment
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Accused Products
Abstract
A method of logging a perforation tunnel and associated features of the perforation tunnel can include the following features. A logging device including an ultrasonic transducer is located downhole into a well. The well has a casing. The ultrasonic transducer has a focal point that is a distance from the ultrasonic transducer so as to be behind the inner face of the casing. An ultrasonic signal is projected from the ultrasonic transducer. A reflection of the ultrasonic signal is reflected from an internal portion of the perforation tunnel, the perforation tunnel extending through the casing and into formation. A transit time is measured between transmission and reception of the ultrasonic signal. A position of the ultrasonic transducer corresponding to the ultrasonic transmission and reception of the reflected signal is determined.
22 Citations
26 Claims
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1. A method of logging a perforation tunnel and associated features of the perforation tunnel, comprising:
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a) locating a logging device including an ultrasonic transducer into a well, the well having a casing, the ultrasonic transducer having a focal point that is a distance from the ultrasonic transducer so as to be behind the inner face of the casing; b) projecting an ultrasonic signal from the ultrasonic transducer; c) detecting a reflection of the ultrasonic signal from an internal portion of the perforation tunnel, the perforation tunnel extending through the casing and into formation; d) measuring a transit time between transmission and reception of the ultrasonic signal; e) determining a position of the ultrasonic transducer corresponding to the ultrasonic transmission and reception of the reflected signal; f) repeating steps b)-e) multiple times and recording resultant data; g) processing the resultant data with a computer and determining a dimension of the perforation tunnel; and wherein the ultrasonic transducer is located a standoff distance from the wellbore casing at least one-third of a length of a minimum open tunnel length required to measure; the standoff distance being so that reflections from the casing reverberate and substantially dissipate before a reflection from inside the perforation tunnel is received by the ultrasonic transducer. - View Dependent Claims (2, 5, 15, 18)
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3. A method of 1, wherein the ultrasonic signal is within a range of 300 kHz to 3000 kHz.
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4. A method of 1, wherein the ultrasonic signal is approximately 1000 kHz.
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6. A method to detect perforation tunnels and associated features of the perforation tunnels, comprising:
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a) lowering an ultrasonic transducer into a wellbore, the wellbore having a casing lining the wellbore, a perforation tunnel extending through the casing and into the formation; b) positioning the ultrasonic transducer adjacent to and facing into the perforation tunnel, the ultrasonic transducer being a standoff distance from the casing so that reflections from the casing reverberate and substantially dissipate before a reflection from inside the perforation tunnel is received by the ultrasonic transducer; c) projecting an ultrasonic signal; d) detecting a reflection of the ultrasonic signal reflected from an internal portion of the perforation tunnel; e) detecting a reflection of the ultrasonic signal reflected from the inside surface of the casing; f) measuring transit times and amplitudes of the reflection from the casing and of the reflection from inside the perforation tunnel; repeating steps b)-f) and recording the resultant data; processing the resultant data with a computer and determining a depth of the perforation tunnel and a dimension of debris in the perforation tunnel. - View Dependent Claims (7, 8, 9, 10, 11, 16, 19)
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12. A method of determining a depth of a perforation tunnel, comprising:
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lowering a logging device into a wellbore, the wellbore having a casing that lines the wellbore; a perforation comprising a tunnel that extends through the casing into formation; the logging device comprising an ultrasonic transducer; positioning the ultrasonic transducer adjacent to the perforation so as to overlap the perforation in a direction extending along a central longitudinal axis of the perforation; emitting an ultrasonic signal from the ultrasonic transducer into the perforation; receiving reflections of the ultrasonic signal from inside the perforation tunnel; and determining the depth of the perforation tunnel and a dimension of debris in the perforation tunnel. - View Dependent Claims (13, 14, 17, 20)
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21. A method of logging a perforation tunnel and associated features of the perforation tunnel, comprising:
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a) locating a logging device including an ultrasonic transducer into a well, the well having a casing, the ultrasonic transducer having a focal point that is a distance from the ultrasonic transducer so as to be behind the inner face of the casing; b) projecting an ultrasonic signal from the ultrasonic transducer; c) detecting a reflection of the ultrasonic signal from an internal portion of the perforation tunnel, the perforation tunnel extending through the casing and into formation; d) measuring a transit time between transmission and reception of the ultrasonic signal; e) determining a position of the ultrasonic transducer corresponding to the ultrasonic transmission and reception of the reflected signal; f) repeating steps b)-e) multiple times and recording resultant data; g) processing the resultant data with a computer and determining a dimension of the perforation tunnel and a dimension of debris in the perforation tunnel. - View Dependent Claims (22, 23, 24)
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25. A method of 21, wherein the ultrasonic signal is within a range of 300 kHz to 3000 kHz.
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26. A method of 21, wherein the ultrasonic signal is approximately 1000 kHz.
Specification