Wellbore Mechanical Caliper Tool

This application claims priority to U.S. Provisional Application Ser. No. 63/648,754, filed May 17, 2024, the complete disclosure of which is hereby incorporated by reference herein.

Downhole mechanical service tools allow for performing operations within a wellbore. When it is time to decommission the well, cement must be injected between the wellbore and casing. Accurate wellbore measurements are critical for estimating how much cement must be injected between the wellbore and the casing. However, wellbore instability can cause wash-outs and irregularities in the wellbore diameter. These irregularities make it difficult to accurately calculate the required cement volume to properly seal the wellbore.

Mechanical calipers are generally used in wireline operations to measure wellbore diameter. Current calipers, however, require an additional wireline trip to acquire the measurements. Such a wireline trip can take days, which extends the time and cost of a drilling operation.

To advance the application of well decommissioning without an additional wireline trip for measuring a wellbore diameter, a new mechanical caliper is needed.

Described herein is a caliper tool for measuring wellbore diameter during Pull Out of Hole (“POOH”) operations in the wellbore drilling process. The caliper tool can be installed on a wireline assembly so that it can be used in conjunction with other drilling operations. In other words, the caliper tool does not require an additional wireline trip.

The caliper includes a collar and measurement bands coupled to the collar at one end and sliding blocks on the other. When the caliper tool is activated, the sliding blocks move axially within the collar. The measurement bands extend radially from the collar until they make contact with the inner wellbore wall. The measurement bands can extend from their inherent qualities or from an external force being applied. For example, the measurement bands can be flexible bands that arc outward from the collar when no force pulls them toward the collar. Alternatively, springs can provide a force that extends the measurement bands.

Movement of the measurement bands causes the sliding blocks to move axially within the collar. The position of a sliding block in the collar indicates how far the corresponding measurement band has extended from the collar. Electromagnetic sensors in the caliper tool measure an electromagnetic field created by magnets in the sliding blocks. These measurements are used to calculate the positions of the sliding blocks, and subsequently to calculate how far the measurement bands are extended from the caliper tool. These calculations can then be used to calculate the wellbore diameter.

The caliper tool includes an actuating mechanism that is used for activating the caliper tool. When deactivated, the measurement bands can be flush or nearly flush to the collar to protect the measurement bands while the caliper tool is lowered into the wellbore. Alternatively, the measurement bands can be positioned within helical depressions of an offset component that protects the measurement bands. The actuating mechanism can include an actuating member that applies a force on the sliding blocks to keep the measurement bands in a safe position while the caliper tool is lowered into the wellbore. The actuating member can be held in place by a dynamic member that is in turn held in place by a constraining member. The constraining member is configured to fail when fluid is pumped into the actuating mechanism and creates a differential pressure across the dynamic member above a certain threshold.

When the constraining member fails, a series of events can occur that cause the actuating member to release the sliding blocks. In one example, the high pressure can cause the dynamic member to move away axially from the actuating member. The pressure can then be lowered, and a spring coil can push the dynamic member toward the actuating member. This releases the sliding blocks and allows the measurement bands to expand until they contact the wall of the wellbore.

In another example, the dynamic member and actuating member can interlock with each other via castellations. The high differential pressure causes the dynamic member and actuating member to separate, and a cam profile in the actuating member causes the actuating member to rotate so that the dynamic member and actuating member no longer interlock. The pressure can be increased again to rotate the actuating member so that the dynamic member and actuating member again can interlock. This allows unlimited activation and deactivation of the caliper tool. Various other cam profiles and actuating mechanisms are described herein.

The measurement bands can extend radially from the collar, which causes the sliding blocks to move within the collar. Electromagnetic sensors in the collar measure an electromagnetic field created by magnets in the sliding blocks to determine the position of the sliding blocks. The position of the sliding blocks is used to calculate the distance that the measurement bands extend and to calculate the wellbore diameter. The caliper tool includes an actuating mechanism that holds the sliding blocks in place until a differential pressure is applied by pumping fluid into the caliper tool.

A downhole deployable offset module is described for protecting other modules in a wireline assembly from damage resulting from contact with the wellbore wall. The offset module includes a piston coupled to blades or discs. The blades are coupled to angled members that convert advancement of the piston to radial deployment of the blades. When fluid pumped through the offset module creates a differential pressure above a certain threshold, the piston is activated and advances axially. This causes the blades to radially deploy. The piston stops advancing when the blades contact the inner surface of the wellbore. This centers the offset module in the wellbore. Strategically placing multiple offset modules in a wireline assembly can protect other modules by keeping them centered in the wellbore. For example, an offset module can be placed at either end of a caliper tool to protect exposed measurement bands.

The offset module can include a ratchet ring with threads that complements threads on the piston. The threads have flank angles that are biased in a single direction so that an axial force applied to the ratchet ring allows the ratchet ring to expand over the piston in the single direction. This allows the piston to advance in a single direction so that the blades can be deployed, but not retracted until manually reset. The ratchet ring can have a failure setting where it fails when a threshold pressure is applied on the piston. This can help prevent the offset module from getting stuck in the wellbore.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the embodiments, as claimed.

Reference will now be made in detail to the present exemplary examples, including examples illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. The described examples are non-limiting.

In the specification and appended claims: the terms “connect”, “connection”, “connected”, “in connection with”, and “connecting” are used to mean “in direct connection with” or “in connection with via another element”; and the term “set” is used to mean “one element” or “more than one element”. As used herein, the terms “up” and “down”, “upper” and “lower”, “upwardly” and downwardly”, “upstream” and “downstream”; “above” and “below”; and other like terms indicating relative positions above or below a given point or element are used in this description to more clearly described some embodiments of the invention. However, when applied to equipment and methods for use in wells that are deviated or horizontal, such terms may refer to a left to right, right to left, or other relationship as appropriate.

A wellbore caliper tool is provided for measuring a wellbore diameter without an additional wireline trip. The caliper tool includes a collar, measurement bands coupled to the collar at one end and sliding blocks on the other. The measurement bands can extend radially from the collar, which causes the sliding blocks to move within the collar. Electromagnetic sensors in the collar measure an electromagnetic field created by magnets in the sliding blocks to determine the position of the sliding blocks. The position of the sliding blocks is used to calculate the distance that the measurement bands extend and to calculate the wellbore diameter. The caliper tool includes an actuating mechanism that holds the sliding blocks in place until a differential pressure is applied by pumping fluid into the caliper tool.

is an example illustration that shows a cross-section view of an embodiment of the invention, a wellbore caliper tool. The caliper toolincludes a collar. The collarhas a cylindrical or ring-like shape and secures other parts in place. The caliper toolincludes one or more measurement bandsthat are coupled to the collarat a first endand to a sliding blockat a second end. The measurement bandcan be any component that can extend from the collarwhile coupled to the collarand sliding block. In one example, the measurement bandcan be a flexible band that has an arc profile when no external forces act upon it. The arc profile of the measurement bandflattens if its ends,are forced apart. Conversely, the ends,are forced apart if the arc profile is flattened by an external constraint. As a result, the height of the arc can be determined based on the displacement of the ends,.

Other types of measurement bandscan be used. For example, the measurement bandcan include two arm members pivotally coupled to each other. In one example, the two arm members can be pivotally coupled by a cylindrical roller that can roll when in contact with surrounding rock formations. Another component, such as a bow spring or coil spring, can apply a force on the two arm member that causes the coupling point to extend from the collarunless another stronger forces prevents it from doing so.

An actuation mechanisminside the collarcan activate and deactivate the measurement bandsby applying or releasing force to the sliding block. For example, the actuation mechanismincludes an actuation driverand an actuation member. When the caliper toolis deactivated, the actuation driverapplies a force to the actuation member, which in turn applies a force on the sliding blockthat causes the sliding blockto pull the second endsof the measurement bandsaway from their respective first ends. This flattens the measurement bandsagainst the collar, thereby protecting the measurement bandsfrom the wellbore. To activate the caliper tool, the actuation mechanismsimply releases the force applied on the sliding block, which causes the measurement bandsto contract and form an arc shape outward from the collar.

In one example, the caliper toolcan include multiple measurement bandsthat are coupled at a second endto the same sliding block. Alternatively, each measurement bandcan be coupled to a different sliding block, and the actuation mechanism can apply a force to all the sliding blocks simultaneously.

The actuation mechanismcan include a constraining memberthat can mitigate unintentional activation of the actuation mechanism. For example, when the caliper toolis deactivated, the constraining membercan lock the actuating memberin place so that the sliding blockremains in an axially extended position to keep the measurement bandsflattened against the collar. The constraining membercan unlock the actuating memberwhen the caliper toolis activated.

The caliper toolincludes an electronics chassisthat contains electrical components for sensing the position of the sliding blockand store the measurements in digital memory.is an example illustration that shows a cross-section view of the sliding blockand the electronics chassis. The sliding blockincludes one or more magnetsthat create a magnetic field. The sliding blockcan include one magnetfor each measurement band. The electronics chassisincludes electronic magnetic sensorsthat are aligned with the axis of the collar. The electromagnetic sensorscan be any sensors that can measure the magnetic field. The electromagnetic sensorscan be calibrated to determine the position of the magnetsbased on readings of the magnetic field. The position of the magnetsindicates the position of the sliding block(s), which can then be used to calculate the arc height of the measurement bands, and subsequently the wellbore width. This is described in more detail later herein.

In an example, the caliper toolcan be activated by pumping fluid through the caliper tool. This causes the flowrate of fluid through the caliper toolto increase, which in turn causes various components of the actuation mechanismto move.are example illustrations that show multiple states of the actuation mechanismduring the activation process.shows a first state where a dynamic memberof the actuation driveris separated from the actuation member. For example, the actuation drivercan include a static memberand a dynamic member. The increase in flowrate causes a pressure differential across the dynamic memberto increase. The constraining membersare designed to fail when a target pressure differential has been generated across the dynamic member. After the constraining memberfails, the pressure differential from the fluid flowrate causes dynamic memberto move away from the actuation member. There is also a pressure differential across the actuation memberduring the activation operation, forcing the actuation memberto maintain its position during the increased flowrate stage of the activation operation.

The caliper toolincludes a coil springthat applies a force on the actuation membertoward the actuation driver. During the water phase of the drilling operation, the coil springis not strong enough to overcome the pressure from the pumped fluid, so the actuation memberstays in place. However, when the water phase ends, and the flowrate is decreased or eliminated, the coil springcreates sufficient force to move the actuation memberto the dynamic member, which is shown in. This state of the actuation mechanismremoves the constraint applied to the sliding blockby the actuation member, which allows the measurement bandsto activate.

The measurement bandscan be deactivated by increasing the flowrate through the caliper toolagain. However, the target flowrate is lower than the flowrate required to fail the constraining members. This increased flowrate causes the actuation mechanismto return to second state illustrated in, and constrain the measurement bandsto the deactivated position.

In an embodiment, the caliper toolcan be positioned in a wireline assembly between (a coupled to) deployable offset modules that protect and centralize the caliper tool. The deployable offset modules can include offset features that expand to a predetermined dimension under-gauge to protect the measurement bands. For example, while the wireline assembly is inside a wellbore, the offset features contact the surrounding rock formation, thereby preventing the measurement bandsfrom doing so.

Although the caliper toolshows the measurement bandsbeing axially aligned with the collar, other configurations are possible. For example,is an example illustration that shows another embodiment, a caliper tool, with measurement bandsthat are helically aligned with the collar. The collar, measurement bands, and sliding blockscorrespond to the like-named components of. For example, the collarcorresponds to the collar, the measurement bandsto the measurement bands, and sliding blocksto the sliding blocks. The caliper toolincludes an offset componentthat includes helical depressionsthat match the helical profile of the measurement bandsrest in. An offset componentwith a helical profile produces less vibration than a straight profile if the offset componentcontacts the wellbore while drilling.

While the caliper toolis deactivated, the measurement bandsare stretched by the sliding blocksso that they pass through the depressionsbeneath the outer annular surface of the offset component. This maintains the helical arc profile of the measurement bandswhen deactivated. While the caliper toolis lowered into a wellbore, and while any other drilling operations are being performed, the offset componentmakes contact with the surrounding rock formation, thereby protecting the measurement bands. Also, when deactivated, the measurement bandsneed not be flush, or nearly flush, with the collar, thereby reducing stress on the measurement bands.

is an example illustration of a cross-section view of the caliper tool. The caliper toolincludes the same components as the caliper tool, but in a different configuration. The actuation driver, actuation member, constraining member, and electronics chassiscorrespond to the like-named components of. For example, the actuation drivercorresponds to the actuation driver, the actuation memberto the actuation member, the constraining memberto the constraining member, and the electronics chassisto the electronics chassis.

show the operation of an embodiment of a wellbore caliper tool. The initial position of the actuation driverand the actuation memberis shown in, with a collar pinmovable within the recess of a cam profilebeing in an end of a straight portion. In this position, the differential pressure can vary within the typical drilling operating range without activating the measurement units. These changes in differential pressure will only vary the position of the actuation driveraxially, as the collar pinmoves in the straight portion. This decoupling between the motion of the actuation driverand the actuation memberis critical to this embodiment.

To transition into activation mode, differential pressure is increased which causes the collar pinto engage a ramp in the other end of the cam profileand rotate the actuation driver. Motion of the actuation driveris inhibited by the collar pinafter sufficient differential pressure has been applied. This is shown in.

At this position, the differential pressure is reduced, and the coil springreturns the actuation driverto its original position. When the actuation driveris returning to its original position, the collar pinengages a ramp opposing the previous straight portion of the cam profile, further rotating the actuation driveras shown in.

As the actuation driverreturns to its original position, the extended portions of the actuation driverand the actuation memberare in contact, as shown in. This transfers force from the coil springto the actuation member, which moves the actuation member, thereby activating the measurement units.

To deactivate the measurement units, high differential pressure is required again. Increased differential pressure causes the collar pinto move to the other end of the cam profileagain, which engages the ramp in the other end and rotating the actuation driver, misaligning the extended sections of the actuation driverand the actuation member. This is shown in.

The motion of the actuation driveris inhibited by the collar pinafter sufficient differential pressure has been applied. At this position, the differential pressure is reduced, and the coil springreturns the actuation driverto its original position. When the actuation driveris returning to its original position, the collar pinengages a ramp opposing the previous straight portion of the cam profile, further rotating the actuation driveras shown in. Once the actuation driverreturns to its original position, the extended portion of the actuation driverengages the depressed portion of the actuation memberas shown in, resetting the sequence.

is an illustration of a cross-section view of another embodiment, a caliper tool. Like other embodiments described previously, the caliper toolincludes a collar, measurement band, sliding block, actuation driver, actuation member, and electronic chassis. The caliper toolalso includes a tattle-tale apparatus. The tattle-tale apparatusprovides a pressure signal to the operator when the actuation memberchanges position from the deactivated state to activated state.

show the operation of an embodiment of a wellbore caliper tool similar to the embodiment illustrated in, other than, as shown in, the absence of castellations, and the addition of an insertin the internal bore of the actuation memberand a toothin the external bore of the actuation driver, with the actuation memberhousing a portion of the actuation driver. The actuation driverdrives the actuation membervia contact of the insertand the tooth.

After maintaining the differential pressure with the upper operational magnitude, the differential pressure is decreased, and a coil springreturns the actuation driverto its original position via the path shown inand. It should be noted that the insert of the actuation memberdoes not contact the toothof the actuation driverwhen the actuation driverreturns to its original position in this profile.

To engage the second profile, an intermediate differential pressure is maintained across the actuation driver. This positions the collar pinmidway along the cam profileas shown in. When the differential pressure is decreased at this point, the coil springreturns the actuation driverback to its original position, however the collar pinwill move to an alternate path in the cam profileas shown in, thereby entering the path of the second profile shown in.

From this position, the differential pressure is increased to begin the activation of the measurement units. This causes the collar pinto move to an upper stop different from the previous upper stop in the cam profile, as shown in. When the collar pintravels along this path, the toothof the actuation driver engages the insert of the actuation member.

When the collar pinreaches this point, the differential pressure is decreased which causes the coil springto return the actuation driverto its original position, as shown in. At this point, the measurement units are activated and no further energization is required to obtain measurements.

To deactivate the measurement units, the differential pressure is increased to a high magnitude which causes the collar pinof the actuation driverto move to an upper stop different from the previous upper stops in the cam profile, as shown in.

After maintaining the differential pressure, the differential pressure is decreased, and the coil spring returns the actuation driverto its original position, as shown in. The insert of the actuation memberdisengages from the toothof the actuation driverduring the movement of the actuation driver.

is an example illustration of an actuation mechanismthat can be used in conjunction with some of the embodiments described herein. The actuation mechanismuses cam profiles (not shown) and resettable locking featuresfor when greater actuation force is required. This can be advantageous compared to the caliper toolbecause the differential pressure across the actuation driversupplies the force required to open the actuation member, rather than coil spring force. Compared to the caliper tool, the cam profile of this alternative actuation mechanismcan be designed to follow a similar operating philosophy, but with simpler cam profiles. The specific cam profile of this design is not explored in detail. The focus is on the behavior of the latching feature.

The actuation driverincludes castellations at one end. These castellations interface with protruding features from the actuation member. When the caliper is being activated, a high magnitude differential pressure is applied across the actuation driver. This causes the actuation drivercastellation flats and the actuation memberprotruding flats to contact. This allows the actuation memberto be moved axially. Sufficient axial movement causes the locking featuresin the actuation memberand collarto engage. After applying the high magnitude differential pressure across the actuation driver, the pressure is decreased, causing the actuation driverto return to its home position. The actuation driveris rotated by 60 degrees on the return stroke due to the ramp of the cam profile.

To deactivate the caliper, a high magnitude differential pressure is reapplied across the actuation driver. However, the castellations are now aligned with flexible membersof the actuation member. This causes the flexible membersto contact an inner ramp on the actuation drivercastellations. As the actuation drivermoves axially, the flexible membersare elastically bent inward toward the center axis of the collar. This causes the locking featuresto disengage, releasing the actuation member. After applying the high magnitude differential pressure across the actuation driver, the pressure is decreased, causing the actuation driverto return to its home position. The actuation driver is rotated by 60 degrees on the return stroke due to the ramp of the cam profile.

is an illustration of an example method for measuring a wellbore diameter using a wellbore caliper tool. At stage, the caliper tool is installed on a drill string. For example, the drill string can include various modules coupled to each other. The caliper tool can be strategically installed based on the other modules and where the desired measurements will be taken. In one example, the caliper tool can be installed below a pump module so that the pump module can pump drilling fluid into the caliper tool necessary for activation. After installation, the caliper tool can be inserted into the wellbore as part of the wireline assembly.

At stage, pressure in the bore is increased by increasing flow of drilling fluid through the drill string. For example, a pump module in the drill string can include a pump that pumps drilling fluid into the wellbore. The pressure level can be controlled at the surface. The pump can pump drilling fluid at a pressure that causes the caliper tool to activate according to predetermined specifications.

At stage, when a threshold pressure for activation has been reached, the constraining members of the caliper tool fail, causing the actuation member to separate from the actuation driver. The actuation member and actuation driver can be castellated, and initially be locked together through interlocking castellations. The constraining members can keep the actuation member and actuation driver from separating. When the constraining member fails, and due to the pressure, the actuation member and actuation driver can axially separate until the castellations no longer interlock. In some examples, the actuation driver, or a subcomponent thereof, can move away from the actuation member while the actuation member remains in its position.