Untethered, unpowered, rollable device to sense condition of pipeline wall

• US 8,098,063 B2
• Filed: 02/07/2006
• Issued: 01/17/2012
• Est. Priority Date: 02/07/2005
• Status: Active Grant

• Current Assignee: Pure Technologies Limited (Xylem, Inc.)
• Original Assignee: Pure Technologies Limited (Xylem, Inc.)
• Inventors: Paulson, Peter O.
• Primary Examiner(s): PATIDAR, JAY M
• Application Number:
  US11/814,921
• Publication Number:
  US 20080204008A1
• Time in Patent Office: 2,170 Days
• Field of Search: 324220-221, 735/92
• US Class Current: 324/220
• CPC Class Codes: F16L 2101/30 Inspecting, measuring or testing
• CPC Class Codes: F16L 55/38 driven by fluid pressure
• CPC Class Codes: F16L 55/46 Launching or retrieval of pigs or moles
• CPC Class Codes: F16L 55/48 Indicating the position of the pig or mole in the pipe or conduit
• CPC Class Codes: F17D 1/08 for liquids or viscous products water-main or service pipe systems E03B7/04; domestic hot-water supply systems F24D17/00
• CPC Class Codes: F17D 3/00 Arrangements for supervising or controlling working operations
• CPC Class Codes: F17D 3/01 for controlling, signalling, or supervising the conveyance of a product
• CPC Class Codes: F17D 3/08 the different products being separated by "go-devils", e.g. spheres cleaning devices moved along inside a pipe-lines by fluid pressure B08B9/04; pigs or moles per se, their launching and detection F16L55/26
• CPC Class Codes: F17D 5/00 Protection or supervision of installations arrangements for protecting foundations E02D31/00; protecting pipes from damage or internal or external wear F16L57/00, against corrosion and scale F16L58/00; investigation of the fluid-tightness of structures G01M3/00
• CPC Class Codes: F17D 5/06 using electric or acoustic means
• CPC Class Codes: G01M 3/005 using pigs or moles G01M3/246, G01M3/2823 take precedence
• CPC Class Codes: G01M 3/246 using pigs or probes travelling in the pipe
• CPC Class Codes: G01N 27/82 for investigating the presence of flaws
• CPC Class Codes: G01N 33/28 Oils , i.e. hydrocarbon liquidsgaseous fuels G01N33/225; edible oils or edible fats G01N33/03
• CPC Class Codes: G01N 33/383 Concrete, cement

Abstract

A sensor unit for use in sensing conditions in a pipeline comprises an untethered a ball-shaped surround adapted to roll along the interior surface of a pipeline, and instrument package within the ball-shaped surround. The package contains at least one magnetometer or accelerometer. Preferably, three magnetometers, arranged orthogonally, are present. Other sensors can also be present as required, such as an acoustic sensor to detect leaks and a temperature or chemical sensor. Recording means record the data acquired by the magnetometer(s) or accelerometer and the sensors, and optionally also record a timing trace.

Claims

1. A tether-free sensor unit of spherical or ellipsoidal shape with no motorized propelling means, for inspecting a pipeline which contains a moving liquid, which sensor unit comprises a sensor package containing a sensor to sense the number of revolutions of the sensor unit when such unit rolls along the bottom of the interior of the pipeline selected from at least one magnetic sensor and at least one accelerometer, and recording means for recording data sensed by said sensor, said sensor unit being of greater density than the density of the liquid in the pipeline to be inspected, whereby it can roll along the bottom of the pipeline to be inspected.

2. A sensor unit as claimed in claim 1, in which said sensor is three magnetometers, arranged orthogonally to one another.

3. A sensor unit as claimed in claim 2, additionally comprising an acoustic sensor.

4. A sensor unit as claimed in claim 3, additionally comprising a ball shaped outer surround which surrounds and protects the sensor package.

5. A sensor unit as claimed in claim 1, additionally comprising a temperature sensor to sense the temperature of liquid surrounding the sensor unit.

6. A sensor unit as claimed in claim 1, additionally comprising an acoustic transmitter or transponder.

7. A sensor unit as claimed in claim 6, in which the transmitter or transponder transmits a range of frequencies.

8. A sensor unit according to claim 6, in which the transmitter or transponder emits at least one frequency above 20 KHz.

9. A sensor unit according to claim 6, in which the acoustic transmitter or transponder transmits a range of frequencies comprising a swept pulse, in a range between 1 KHz and 200 KHz,

10. A sensor unit as claimed in claim 6, additionally comprising a battery to power said recording means and the transmitter or transponder.

11. A sensor unit as claimed in claim 1, in which the sensor unit is spherical and has a diameter of less than half and greater than 1/10 of the diameter of the pipeline to be inspected.

12. A sensor as claimed in claim 1, in which the sensor unit is ellipsoidal and the length of its major axis is less than ½

of the diameter of the pipeline to be inspected.

13. A method of inspecting a pipeline which contains flowing liquid, comprising;

(a) providing a sensor unit which comprises a package containing a sensor selected from at least one magnetic sensor and at least one accelerometer, and means for recording data sensed by said sensor, said sensor unit being of greater density of the liquid in the pipeline to be inspected, and

(b) allowing the sensor unit to be rolled along the bottom of the interior of the pipeline by the flow of the liquid, while recording a signal representative of the number of revolutions that the surface of the sensor unit has made.

14. A method as claimed in claim 13, in which the sensor unit comprises an acoustic transmitter or transponder, and the method includes emitting signals from the transmitter or transponder and receiving such signals at least one location along the pipeline.

15. A method as claimed in claim 14, in which signals are emitted at a frequency above 20 KHz.

16. A method as claimed in claim 13, in which signals are emitted at a range of frequencies comprising a swept pulse, in a range between 1 KHz and 200 KHz.

17. A method as claimed in claim 13, in which said sensor is three magnetometers, arranged orthogonally to one another.