Boring or penetrating the earth – With signaling – indicating – testing or measuring
Reexamination Certificate
1999-06-10
2001-06-05
Pezzuto, Robert E. (Department: 3671)
Boring or penetrating the earth
With signaling, indicating, testing or measuring
Reexamination Certificate
active
06241028
ABSTRACT:
FIELD OF THE INVENTION
The invention relates to a method and system for measuring data in a fluid transportation conduit and to a sensing device that forms part of such a system.
BACKGROUND TO THE INVENTION
If is often desirable to measure physical data, such as temperature, pressure and fluid velocity and/or composition in a fluid transportation conduit. However, it is not always feasible or economically attractive to provide the conduit with sensors which are able to measure such data along the length of the conduit over a prolonged period of time. In such circumstances so called intelligent pigs have been used to measure data, but since these pigs are pumped through the conduit they are large pieces of equipment which span the width of the conduit and therefore are not suitable to make in-situ measurements in the fluid flowing through the conduit. Also tethered sensor probes have been used to measure data in conduits, but these probes have a limited reach and involve complex and expensive reeling operations.
International patent application PCT/US97/17010 discloses an elongate autonomous robot which is released downhole in an oil and/or gas production well by means of a launching module that is connected to a power and control unit at the surface. The elongated robot is equipped with sensors and arms and/or wheels which allow the robot to walk, roll or crawl up and down through a lower region of the well. The insertion of the launching module into the well and the movement of the robot through the well is a complex operation and requires complex, fragile and expensive propulsion equipment.
U.S. Pat. No. Re. 32,336 discloses an elongate well logging instrument which is lowered into a borehole at the lower end of a drill pipe. When the pipe has reached a lower region of the borehole the logging tool is released, lowered to the bottom of a well and retrieved by means of an umbilical that extends through the drill pipe towards the wellhead.
U.S. Pat. No. 3,086,167 discloses a borehole logging tool which is dropped through a drill string to a location just above the drill bit to take measurements during drilling. The tool can be retrieved from the drill string by means of a fishing tool.
U.S. Pat. Nos. 4,560,437 and 5,553,677 and International patent application WO 93/18277 disclose other elongate downhole sensor assemblies that are removed from the well by means of a fishing tool or an umbilical.
It is an object of the present invention to provide a method and system for measuring data in a fluid transportation conduit over a prolonged period of time and which do not require permanently installed sensors, complex wireline tools and/or robotic transportation tools and which employ a sensing device which can be moved through the conduit without obstructing the conduit so that it is able to make in-situ measurements in the fluid within the conduit.
SUMMARY OF THE INVENTION
The method according to the invention comprises the steps of:
providing one or more sensing devices, each device comprising sensors for measuring physical data, a data processor for processing the measured data, and a protective shell containing the sensors and data processor, which shell has a smaller average outer width than the average internal width of a conduit from which measurements are to be made so that fluid in the conduit is permitted to flow around the sensing device;
inserting into the conduit the sensing device;
activating the sensors and data processor of at least one inserted sensing device to measure and process physical data in the conduit;
releasing at least one sensing device of which the sensors and data processor are or have been activated in the conduit;
allowing each released sensing device to move over a selected longitudinal distance through the conduit; and
transferring the data processed by the data processor to a data collecting system outside the conduit.
The shell is both robust and compact so that the sensing device is able to travel over a long distance through the conduit and is small relative to the inner width of the conduit so that it does not obstruct the fluid flow through the conduit.
Preferably the sensing devices are not equipped with external mechanical propulsion means, such as propellers, wheels or robotic arms so that the sensor is very compact and is allowed to move freely and passively through the conduit under the influence of hydrodynamic forces induced by fluids flowing through the conduit, buoyancy, gravity and/or magnetic forces exerted to the sensing device.
The method according to the invention can be applied both in open fluid transportation conduits that are formed, for example, by a channel through which liquid flows, and in closed fluid transportation conduits where the conduit has a tubular shape. For example, open conduits could be streams or rivers, aqueducts, or sewers. For closed conduits it is preferred that each sensing device has a substantially globular protective shell and is released in a tubular conduit which has an average internal diameter which is at least 20% larger than the average external diameter of the spherical protective shell and the sensors and data processor form part of a micro electromechanical system (MEMS) with integrated sensory, navigation, power and data storage and/or data transmission components.
The method according to the invention is very attractive for use in downhole tubular conduits that form part of an underground oil and/or gas production well. In that case it is preferred that the sensing devices have a spherical protective shell with an outer diameter which is less than 15 cm and which are each induced to move along at least part of the length of the wellbore.
Suitably a plurality of sensing devices are stored at a downhole location near a toe of the well and released sequentially in the conduit, and each released sensing device is allowed to flow with the produced hydrocarbon fluids towards the wellhead. In such case it is preferred that the sensing devices are stored in a storage bin which is equipped with a telemetry-activated sensing device release mechanism and each sensing device comprises a spherical epoxy shell containing a thermistor-like temperature sensor, a piezo-silicon pressure sensor and a gyroscopic and/or multidirectional navigational accelerometer based position sensor, which sensors are powered off a chargeable battery or capacitor, and a data processor which is formed by an electronic random access memory (RAM) chip. Alternatively, or in addition to the navigational accelerometer, a sensor, for example, a sensor effective to detect casing couplings by a Hall effect sensor could be provided to track location by counting couplings. It is also preferred that each sensing device comprises a spherical plastic shell which is equipped with at least one circumferentially-wrapped electrically conductive wire loop which functions as an antenna loop for communications and as an inductive charger for the capacitor or battery and each sensing device is exposed to an electromagnetic field at least before it is released in the wellbore by the sensing device release mechanism, and wherein each released sensing device is retrieved at or near the earth surface and then linked to a data reading and collecting apparatus which removes data from the retrieved sensor device via a wireless method.
If the wellbore comprises a well tubular having a magnetizable, such as a steel, wall or contains a longitudinal magnetizable strip or wire then the sensing device may be equipped with magnetically-activated rolling locomotion components which induce the sensing device to retain rolling contact with the tubular or longitudinal strip or wire when the sensing device traverses the wellbore and the sensing device is equipped with a revolution counter and a sensor for detecting marker points in the well tubular, such as a casing junction and/or bar code marking points, to determine its position in the well tubular. In that case it is preferred that the magnetically-activated rolling locomotion components comprise a magnetic
Bijleveld Aarnoud F.
den Boer Hans J. J.
Kimminau Steve J.
Morris Jerry Lee
Schempf Hagen
Pezzuto Robert E.
Shell Oil Company
LandOfFree
Method and system for measuring data in a fluid... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and system for measuring data in a fluid..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and system for measuring data in a fluid... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2527896