Patent ID: 12210131

The drawing figures do not limit the invention to the specific embodiments disclosed and described herein. The drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the invention.

DETAILED DESCRIPTION

The following detailed description references the accompanying drawings that illustrate specific embodiments in which the invention can be practiced. The embodiments are intended to describe aspects of the invention in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments can be utilized and changes can be made without departing from the scope of the invention. The following detailed description is, therefore, not to be taken in a limiting sense. The scope of the invention is defined only by the appended claims, along with the full scope of equivalents to which such claims are entitled.

In this description, references to “one embodiment,” “an embodiment,” or “embodiments” mean that the feature or features being referred to are included in at least one embodiment of the technology. Separate references to “one embodiment,” “an embodiment,” or “embodiments” in this description do not necessarily refer to the same embodiment and are also not mutually exclusive unless so stated and/or except as will be readily apparent to those skilled in the art from the description. For example, a feature, structure, act, etc. described in one embodiment may also be included in other embodiments, but is not necessarily included. Thus, the technology can include a variety of combinations and/or integrations of the embodiments described herein.

Aspects of the present disclosure provide a seal pocket detection assembly for removable installation within a well tubing system, for example, at a joint between two or more tubing sections. The seal pocket assembly includes one or more coils disposed within a pressure cavity of the well tubing system and concentrically around a bore of the tubing sections. The one or more coils produce an electromagnetic field that extends into the bore to thereby detect ferrous objects within the bore, such as, tools, debris, or other objects passing through the bore. Wrapping the coils around a diameter of the tubing bore provides a substantially increased detection sensitivity over prior art sensing techniques that place a magnet or other sensor outside of the pressure cavity and at one end of the tubing. It should be understood that the tubing as referred to herein may comprise any of vertically oriented or horizontally oriented portions of tubing, as well as other orientations not explicitly described herein. Further, the tubing sections may be disposed above ground near a well head or below ground at a sub-surface portion of a well.

FIG.1illustrates an exemplary hydraulic fracturing system100relating to some embodiments. The hydraulic fracturing system100comprises a well accessible at a wellhead via a surface well tree102disposed above ground and a plurality of well tubing sections104. In some embodiments, the plurality of well tubing sections104is provided in the surface well tree102, which is disposed at surface level (further discussed below with respect toFIG.5). In such an embodiment where the plurality of tubing sections104is disposed in the well tree102, the plurality of tubing sections is well tree tubing sections. In other embodiments, the plurality of tubing sections104is provided sub-surface, and in such an embodiment are sub-surface tubing sections. Each tubing section of the plurality of tubing sections104comprises one or more pressure containment structures defining an internal bore of the respective tubing section and maintaining an internal pressure of the tubing section. In some embodiments, the plurality of tubing sections104is connected at a respective plurality of joints106. As should be appreciated, the surface well tree102may include the plurality of joints106connecting the plurality of tubing sections104.

In some embodiments, the plurality of tubing sections104may comprise a first portion of vertically oriented tubing sections and a second portion of horizontally oriented tubing sections, such as the horizontal tubing section108, as shown. In some embodiments, the horizontal sub-surface tubing section108may comprise a plurality of openings for generating fractures110at a gas rich underground layer.

The hydraulic fracturing system100may be employed to carry out a hydraulic fracturing operation by pumping fluid from the surface well tree102down the tubing sections104. In some embodiments, an object112including any of one or more tools or other objects may be lowered into the well through the tubing sections104. In some embodiments, the object112comprises any of a perforating gun, an isolation ball, or a wire. For example, a fracturing tool comprising a perforating gun configured to blow holes in the tubing sections may be lowered into the well to generate openings in the tubing sections, such as in the horizontal tubing section108, and perforate through the tubing casing into the surrounding underground formation. Similarly, an isolation ball may be lowered through the boring to selectively isolate a portion of the tubing system by sealing off a set plug associated with a particular section of the bore.

During the process of lowering the object112, including guiding the object112through the surface well tree102, a detection portion of the hydraulic fracturing system100may be used to identify and determine whether the tool or other object is currently traversing the tubing sections104, such as tubing sections104within the well tree. Further, embodiments are contemplated in which a particular type of object (or absence thereof) is identified within the bore of the tubing sections104and/or where the object is located within the tubing sections104. Accordingly, operations of the hydraulic fracturing system100may be informed by the detection of an object detected in the bore of the tubing sections104. For example, one or more valves may be prevented from closing to prevent interfering with a wire that is attached to the object. Accordingly, the wire will not be cut by closing the valves while the wire is currently inside of the bore.

In some embodiments, a control system may be included. For example, the control system may be disposed on the surface at or proximate the well tree102for controlling operations of the hydraulic fracturing system100. The control system may include at least one processor for processing, receiving, transmitting, and/or storing information and for executing computer-readable media. However, it should be understood that a variety of other functions and different locations of the at least one processor are also contemplated.

FIG.2Aillustrates a cross-sectional view of an exemplary tubing section joint200A relating to some embodiments. The tubing section joint200A comprises an upper tubing section202and a lower tubing section204. The upper tubing section202and the lower tubing section204share an internal bore206. In some embodiments, the internal bore206comprises a pressurized internal opening within the tubing sections operable to pump fluids or receive solid objects for traversal through the respective tubing sections.

In some embodiments, one or more flanges208are connected to tubing sections. For example, a horizontally oriented flange208with a diameter of about five and one eighth inches may be included secured to the upper tubing section202. However, it should be understood that flanges with different diameters and structural orientations are also contemplated, for example, to provide a tree of tubing connections and structures. Similarly, one or more plates210may be included, such as an upper plate210disposed around a respective tubing section.

In some embodiments, the upper tubing section202and the lower tubing section204of the exemplary tubing section joint200A are structurally secured using one or more bolts212. In some embodiments, the bolts212may be disposed circumferentially around the exterior of the respective tubing sections. For example, each of the upper tubing section202and the lower tubing section204may comprise a plurality of threaded holes for receiving the bolts212that secure the upper tubing section202and the lower tubing section204at the exemplary tubing section joint200A.

In some embodiments, a seal pocket detection assembly214(also referred to herein as a “seal pocket assembly” in short) is included, disposed at the exemplary tubing section joint200A. The seal pocket assembly214comprises a sealing portion operable to provide a pressure seal to the joint200A and a detection portion operable to detect one or more objects within the bore206, such as the object112. In some embodiments, the object112comprises a ferrous object that is detectable by the seal pocket assembly214. For example, embodiments are contemplated in which a sensing portion of the seal pocket assembly214generates an electromagnetic field within the bore206. Accordingly, the ferrous object may interfere with the electromagnetic field as the object112passes through the bore206in the vicinity of the seal pocket assembly214. Similarly, the seal pocket assembly214may detect the object112within the bore206even if the object112is stationary within the bore206.

Embodiments are contemplated in which the object112includes a non-ferrous object with a ferrous object attached to the non-ferrous object such that the object112is detectable. For example, a perforating gun may be composed of a non-ferrous material, but a ferrous object such as a magnet or metal material is attached to the perforating gun such that the perforating gun can be detected by the seal pocket assembly214. Alternatively, or additionally, in some embodiments, the object112may be ferrous itself or may be coated with a ferrous covering to increase detectability.

Additionally, or alternatively, embodiments are contemplated in which other forms of detection are used. For example, a capacitance detection technique may be used employing one or more capacitance sensors configured to detect a capacitance associated with a presence of the object112disposed in the bore206. Accordingly, non-ferrous materials may be detected based on capacitance. As such, objects or fluids that are non-ferrous may be detected within the bore such as, water and components composed of non-metal material.

In some embodiments, a cable routing port216may be included comprising an opening through one or more of the tubing sections, such as a diagonally oriented hole through a portion of the lower tubing section204, as shown. The cable routing port216may be used, for example, to route one or more cables that provide a communication connection with the seal pocket assembly214. For example, a signal including information indicative of the detected object112may be transmitted through a cable disposed in the cable routing port216. Similarly, in some embodiments, a testing port218is included that comprises an opening through one or more of the tubing sections, such as a diagonally oriented hole through another portion of the lower tubing section204, as shown. The testing port218receives a testing cable220for measuring one or more internal parameters associated with the tubing sections.

Additionally, embodiments are contemplated in which wireless communication may be used. For example, in some embodiments, the cable routing port216is not included and a wireless communication connection is used to transmit signals from the seal pocket assembly214. The wireless communication connection may utilize any of a network connection, a Bluetooth connection, or any other form of wireless communication technique. In some such embodiments, one or more batteries or other form of remote power source may be included for providing electrical power to the seal pocket assembly214. Accordingly, the removability of the seal pocket assembly214becomes advantageous for replacing the batteries within the seal pocket assembly214.

In some embodiments, the seal pocket assembly214comprises a linear variable differential transformer (LVDT) configured to measure displacement of one or more ferrous objects disposed within a bore of the tubing sections. In some such embodiments, the LVDT may include one or more electrical coils that generate at least one electromagnetic field within the tubing section bore. Accordingly, the LVDT may be used to detect the ferrous object based on a change to the electromagnetic field attributed to the ferrous object moving through the electromagnetic field. The LVDT may be integrated directly into the seal pocket assembly214such that the seal pocket assembly214provides both sealing and detection functionality.

FIG.2Billustrates a cross-sectional view of an exemplary tubing section joint200B relating to some embodiments. Similar to the exemplary tubing section joint200A described above, the exemplary tubing section joint200B joins the upper tubing section202and the lower tubing section204. The exemplary tubing section joint200B comprises the seal pocket assembly214disposed at an internal portion of the joint200B between the upper tubing section202and the lower tubing section204. In some embodiments, the exemplary tubing section joint200B also comprises the cable routing port216, as shown.

In some embodiments, the upper tubing section202and the lower tubing section204of the joint200B are secured together using one or more clamps222disposed around an external surface of the respective tubing sections. In some such embodiments, the clamp222provides a clamping force pushing inwards into the joint200B suitable to maintain the connection of the upper tubing section202and the lower tubing section204. In some cases, the clamping force of the clamp222also maintains pressure within the joint200B. Accordingly, embodiments are contemplated in which the seal pocket assembly214is disposed concentrically within the clamp222at the joint106of the upper tubing section202and lower tubing section204.

FIG.3Aillustrates a cross-sectional view of an exemplary tubing section joint106with a dual coil seal pocket assembly relating to some embodiments. The exemplary tubing section joint106comprises a dual coil seal pocket assembly300including an insert body302, a primary coil304, a secondary coil306, and a seal ring308. The components of the dual coil seal pocket assembly300may be arranged as described below. However, it should be understood that a variety of alternative and modified arrangements are also contemplated.

In such embodiments, the insert body302is disposed at an internal portion of the joint106in a pressurized cavity of the bore206. The primary coil304and the secondary coil306are disposed around an external surface of the insert body302such that each of the primary coil304and the secondary coil306is wrapped around the outside of the internal bore206of the tubing sections. The seal ring308is disposed at an inner surface of the insert body302. For example, the seal ring308may be disposed at a bottom end of the insert body302within an internal circumference of the insert body302, as shown, to maintain a pressure inside the joint106. However, it should be understood that embodiments are contemplated in which the seal ring308may be disposed at a top end of the insert body302, not shown. Additionally, or alternatively, embodiments are contemplated in which a first seal ring is disposed at a top end of the insert body302, while a second seal ring is disposed at a bottom end of the insert body302.

The seal pocket assembly300is configured to provide an electromagnetic field within the bore206of the tubing sections. In such embodiments, the electromagnetic field may be generated by one of or both of the primary coil304and the secondary coil306. Alternatively, or additionally, in some embodiments, separate electromagnetic fields may be generated by each coil or the electromagnetic field may be generated by a single coil. The primary coil304and the secondary coil306are concentrically wrapped around the diameter of the bore206to provide an increased detection sensitivity. Accordingly, the electromagnetic field is at least partially generated within the bore206and, in some cases, a central portion of the electromagnetic field coincides with a center of the bore206. As such, the detection sensitivity is increased, for example, relative to detection systems that place coils, sensors, or magnets outside of the tubing sections or at one side of the bore.

Any of active energized coils, passive non-energized coils, or combinations thereof are contemplated. For example, in some embodiments, an active first coil is included that is energized by applying electrical power using a power source of the well tubing system along with a passive second coil that is not actively energized. Accordingly, in some such embodiments, the electromagnetic field is generated by the first coil and detected passively by the second coil. Here, the second coil is operable to detect changes in the electromagnetic field produced by the first coil associated with a ferrous object in proximity to the seal pocket assembly. Further arrangements are also contemplated for the coils of the seal pocket assembly. For example, in some embodiments, both the first coil and second coil are actively energized. Similarly, both coils may be passive, or the coils may be selectively energized. For example, in some embodiments, a signal may be transmitted to switch one or more of the coils from a passive state to an active state to thereby conserve energy associated with constantly energizing the coils.

Additionally, or alternatively, embodiments are contemplated in which the seal pocket assembly214is movably installed in the tubing sections. For example, the seal pocket assembly214may be operable to move vertically through the bore206such that the seal pocket assembly214can be moved across different tubing sections. Accordingly, in some such embodiments, the seal pocket assembly214may be selectively moved to a particular tubing section to determine whether a ferrous object is present within said tubing section. For example, the seal pocket assembly214may be moved responsive to a received operator input.

FIG.3Billustrates a cross-sectional view of an exemplary tubing section joint106with a pair of dual coil seal pocket assemblies relating to some embodiments. The pair of dual coil seal pocket assemblies comprises an upper seal pocket assembly310including an upper insert body312, an upper primary coil314, an upper secondary coil316, and an upper seal ring318. The pair of dual coil seal pocket assemblies further comprises a lower seal pocket assembly320including a lower insert body322, a lower primary coil324, a lower secondary coil326, and a lower seal ring328.

In some embodiments, the upper seal pocket assembly310and upper insert body312may be used in combination to determine a position of an object within the bore206. For example, if the object has been observed passing downward through the upper seal pocket assembly310but has not yet been observed by the lower seal pocket assembly320, it may be determined that the object is currently between the upper seal pocket assembly310and the lower seal pocket assembly320. Further, in some embodiments, the pair of seal pocket assemblies may also monitor a direction of the object. For example, the upper seal pocket assembly310and the lower seal pocket assembly320may be disposed in a series along the bore206to thereby monitoring a direction of the object. Here, the direction may be determined, for example, by comparing interferences in the electromagnetic fields of the respective seal pocket detection assemblies.

In some embodiments, the upper seal pocket assembly310and the lower seal pocket assembly320may provide varying detection sensitivities. For example, the upper seal pocket assembly310may have a higher electromagnetic detection sensitivity than the lower seal pocket assembly320. Alternatively, in some embodiments, the lower seal pocket assembly320may have a higher sensitivity, or the coils may have the same or a substantially similar sensitivity.

The seal pocket assemblies shown are disposed along vertical portions of the tubing sections. However, embodiments are contemplated in which a seal pocket assembly may be disposed elsewhere and in a modified orientation. For example, in some embodiments, a seal pocket assembly may be disposed at a horizontal portion of a tubing section, such as at a cross-flow section of the tubing system. Further, embodiments are contemplated in which the seal pocket assembly may be mounted within the well tree102, at a spool piece, at a gate valve inlet or outlet, or at a wireline connector of the well tubing system. Further, the seal pocket assembly may be disposed at either of a surface portion or a sub-surface portion of the well system. Further still, in some embodiments, the well system may comprise a sub-sea well system such that the seal pocket assembly may be disposed underwater.

In some embodiments, the seal pocket assembly further comprises at least one spacer that contains a pressure within the joint. The spacer may comprise a non-ferrous material as to not interfere with the electromagnetic field. For example, the spacer may comprise a hard plastic, rubber, fiberglass, or other non-ferrous material that provides structural support and a pressure seal within the joint.

FIG.4Aillustrates an exemplary seal pocket assembly214relating to some embodiments. The seal pocket assembly214comprises the insert body302, the primary coil304, and the secondary coil306disposed circumferentially around the internal bore206. In some embodiments, a coil assembly housing402is included for receiving the primary coil304and the secondary coil306. In some embodiments, the coil assembly housing402comprises an enclosure that surrounds at least a portion of the coils. Alternatively, or additionally, in some embodiments, the coil assembly housing402comprises an internal structure that supports the coils304and306. Further, in some embodiments, the coil assembly housing402is at least partially formed of a rigid plastic and/or other non-ferrous material, as to not interfere with the electromagnetic field of the seal pocket assembly214. In some embodiments, the seal ring308may be included internally to the insert body302, not visible in the particular view shown inFIG.4A.

In some embodiments, the insert body302is selectively removable. Accordingly, embodiments are contemplated in which the seal pocket assembly214is removably installed within the tubing sections104at a respective joint106, such that the insert body302and remainder of the seal pocket assembly214may be removed for replacing at least a portion of the seal pocket assembly214. For example, in some embodiments, the insert body302may be removed to replace the coils after a useful lifetime of the coils has expired or after the coils have been deemed defective. Further still, the insert body302may be temporarily removed to repair one or more portions of the seal pocket assembly214. Additionally, in some embodiments, the seal pocket assembly214is removably installed to replace or retrofit an existing seal pocket assembly, for example, to upgrade an existing seal pocket assembly without detection capabilities.

FIG.4Billustrates a cross-sectional view of the exemplary seal pocket assembly214relating to some embodiments. The cross-sectional view shows the cross-section taken at a center of the internal bore206such that respective cross-sections of the insert body302, primary coil304, secondary coil306, and seal ring308are visible. The cross-sectional view also shows the coil assembly housing402including an enclosure encompassing the primary coil304and the secondary coil306. In some embodiments, the coil assembly housing402includes a first cavity for receiving the primary coil304and a second cavity for receiving the secondary coil306. The coil assembly housing402may provide a protective covering to prevent damage and wear to the primary coil304and the secondary coil306in addition to providing structural support and holding the coils in place.

The seal ring308is disposed around the bore206along an inner surface of the insert body302. In some embodiments, the insert body302includes a cutaway portion or groove for receiving the seal ring308on the internal surface of the insert body302. Similarly, the insert body302may include another cutaway portion on an outer surface of the insert body302for receiving the coil assembly housing402, primary coil304, and secondary coil306. In some embodiments, an outer covering406is included on an outer surface of the insert body302. In some such embodiments, the outer covering406is disposed around the coil assembly housing402, as shown, thereby providing further protection and generating a flush outer surface with the insert body302.

FIG.5illustrates an exemplary surface system500relating to some embodiments. The surface system500includes the surface well tree102interfaced with a wireline system502. The wireline system502includes a wireline section and a wireline connector504that interfaces with a portion of the surface well tree102such that a wireline can be lowered through the surface well tree102. The surface well tree102includes a landing hub506, a crown508, a flow cross connection510with an inlet512and an outlet514, an upper master valve516, and a lower master valve518.

In some embodiments, the upper seal pocket assembly310and the lower seal pocket assembly320are integrated into the surface system500. For example, the upper seal pocket assembly310may be integrated into the wireline system502between a section of the wireline system502and the wireline connector504, as shown. Similarly, the lower seal pocket assembly320may be integrated into the surface tree102between the flow cross connection510and the upper master valve516, as shown. However, in some embodiments, other arrangements are contemplated for the seal pocket assemblies. For example, in some such embodiments, at least one of the seal pocket assemblies (or an additional seal pocket assembly) is disposed in a different location within the surface system500or underground at a sub-surface portion of the well. Further, embodiments are contemplated in which a single seal pocket assembly is included.

The wireline system502is configured to receive a wireline or wireline tool into the bore206for lowering through or moving up the plurality of tubing sections104. In some embodiments, the wireline system502includes one or more valves such as a wireline valve configured to selectively seal off a portion of the tubing sections.

In some embodiments, one or more valves of the exemplary surface system500such as, the wireline valve of the wireline system502, the upper master valve516, and the lower master valve518may be operated based at least in part on a signal measured by the upper seal pocket assembly310and the lower seal pocket assembly320. For example, the wireline valve may be prevented from closing based on information collected by the upper seal pocket assembly310indicating that an object is currently disposed in the bore of the tubing sections beneath the wireline system502. Similarly, for example, the upper master valve516and the lower master valve518may be opened responsive to determining that an object is approaching or has passed through the lower seal pocket assembly320.

Embodiments are contemplated in which either of the upper seal pocket assembly310or the lower seal pocket assembly320are disposed elsewhere within the exemplary surface system500. For example, in some embodiments, the lower seal pocket assembly320may be disposed at the flow cross connection510at the joint between two vertical tubing sections and the inlet512and outlet514of the flow cross connection510. Further still, in some embodiments, seal pocket assemblies are included in addition to the upper seal pocket assembly310and the lower seal pocket assembly320.

FIG.6illustrates an exemplary method600for a well tubing system relating to some embodiments. In some such embodiments, any portion of the steps described herein may be carried out on at least one processor, for example, by executing one or more non-transitory computer-readable media storing computer-executable instructions, such as a processor of a control system of the well tubing system.

At step602, an electromagnetic field is generated within the bore206of the tubing sections104. The electromagnetic field may be generated by any combination of coils disposed within the seal pocket assembly, as described above, for example, any combination of energized and passive electrical coils such as the primary coil304, the secondary coil306, the upper primary coil314, the upper secondary coil316, the lower primary coil324, and the lower secondary coil326.

At step604, a change in the electromagnetic field is detected associated with one or more ferrous objects passing through or approaching the vicinity of the electromagnetic field. For example, in some embodiments, a sensor may be configured to measure a signal associated with the electromagnetic field over time. Accordingly, the sensor may receive a first signal associated with a resting state in which there is no object near the seal pocket assembly such that there is no interference present in the electromagnetic field. The sensor may receive a second signal associated with a subsequent state in which there is an object near the seal pocket assembly that interferes with the electromagnetic field. In some such embodiments, the change may be detected by comparing the second signal to the first signal.

At step606, the ferrous object is identified within the bore206based on the detected change in the electromagnetic field due to the presence of the ferrous object within the electromagnetic field. In some embodiments, the object may be identified by comparing the first signal to the second signal, as described above. In some embodiments, parameters such as any of a size, direction, and speed of the object may be deduced based at least in part on the detected signals or comparison thereof. For example, if there is a large change in the electromagnetic field it may be determined that a relatively large object has passed through the seal pocket assembly or that the object is traveling at a high speed. In one example, where the object112comprises a wire or cable, a gauge of the wire may be estimated based at least in part on the interference detected within the electromagnetic field. Accordingly, a plurality of wires having different gauges may be distinguished between such that a particular type of wire may be identified by its effect on the electromagnetic field.

At step608, at least one operation of the well tubing system is adjusted based at least in part on the detection and/or identification of the object. For example, embodiments are contemplated in which one or more valves are adjusted based on detecting an object within the bore (or determining that no object is currently present in the bore). Here, a valve may be opened based on a determination that an object is traveling through the bore or a valve may be closed based on a determination that an object has exited the bore or is otherwise not currently present or in proximity to the respective valve. Further, embodiments are contemplated in which valves may be opened and/or closed based on a proximity of an object traveling through the bore as determined by the seal pocket assembly. Further still, in some embodiments, one or more valves may be prevented from closing responsive to detection of an object in the bore. For example, if a wire is detected within the bore, one or more valves may be locked and prevented from closing as to prevent closing of the valves around the wire from cutting or damaging the wire or any other objects attached thereto.

Alternatively, or additionally, in some embodiments, adjusting operation based on the identified object includes transmitting a notification to an operator and/or to a control system of the hydraulic fracturing system100. For example, a signal comprising information indicative of the detected object may be transmitted through a cable, such as the cable disposed in the cable routing port216. The signal may be transmitted to a control system at the surface portion, which may notify an operator or automatically adjust operation of the hydraulic fracturing system100based on the signal. In some such embodiments, a notification signal may be transmitted via either of a wired or wireless communication connection, such as over a wireless network to notify an operator or another remote control system of the object. For example, an embodiment is contemplated in which a light is switched on responsive to determining that an object is present within the bore206at a particular seal pocket assembly and the light is switched off responsive to detecting the absence of the object. However, it should be understood that a variety of different suitable notification techniques are also contemplated.

In some embodiments, the seal pocket detection assembly214is disposed around a main bore of the tubing, as described above. However, further embodiments are contemplated in which a seal pocket detection assembly may be disposed around another bore or around one or more ancillary lines that feed into the main bore (or are otherwise connected to the main bore). Accordingly, in certain isolation ball operations where the isolation ball is inserted through one of the ancillary lines, for example, the isolation ball may be detected by the seal pocket detection assembly as it passes through the ancillary line to confirm that the isolation ball was injected correctly and successfully cleared at least a portion of a stack of tubing sections.

Clause 1. A seal pocket detection assembly disposed at a joint of one or more well tree tubing sections, the seal pocket detection assembly comprising: a removable insert body; one or more seals disposed at an inner surface of the removable insert body, the one or more seals providing a pressure seal to the joint; and a coil assembly disposed at least partially within the pressure seal of the joint, the coil assembly comprising: a coil assembly housing disposed at an outer surface of the removable insert body; and at least one coil disposed around a bore of the one or more well tree tubing sections in a cavity of the coil assembly housing, wherein the at least one coil produces an electromagnetic field within the bore, wherein the coil assembly detects a ferrous object disposed within the bore of the one or more well tree tubing sections based on a change to the electromagnetic field associated with the ferrous object passing through the electromagnetic field.

Clause 2. The seal pocket detection assembly of clause 1, wherein the coil assembly further comprises: a coil assembly cover disposed over the outer surface of the removable insert body.

Clause 3. The seal pocket detection assembly of any of clause 1 or clause 2, wherein the coil assembly further comprises: a primary coil disposed in a first cavity of the coil assembly housing; and a secondary coil disposed in a second cavity of the coil assembly housing.

Clause 4. The seal pocket detection assembly of any of clause 1 through clause 3, wherein the coil assembly housing comprises a plastic enclosure defining the first cavity and the second cavity.

Clause 5. The seal pocket detection assembly of any of clause 1 through clause 4, wherein the ferrous object detected by the coil assembly includes a perforating gun.

Clause 6. The seal pocket detection assembly of any of clause 1 through clause 5, further comprising: a spacer that contains a pressure within the joint of the one or more well tree tubing sections, the spacer comprising a non-ferrous material such that the spacer does not interfere with the electromagnetic field.

Clause 7. The seal pocket detection assembly of any of clause 1 through clause 6, wherein the ferrous object is attached to a non-ferrous component for detection of the non-ferrous component.

Clause 8. A seal pocket detection system disposed at a joint of one or more well tree tubing sections, the seal pocket detection system comprising: an upper seal pocket detection assembly comprising: an upper removable insert body disposed at an upper portion of the joint; an upper coil assembly comprising: an upper coil assembly housing disposed at an outer surface of the upper removable insert body; a primary upper coil disposed around a bore of the one or more well tree tubing sections in a first cavity of the upper coil assembly housing; and a secondary upper coil disposed around the bore of the one or more well tree tubing sections in a second cavity of the upper coil assembly housing; and a lower seal pocket detection assembly comprising: a lower removable insert body disposed at a lower portion of the joint; a lower coil assembly comprising: a lower coil assembly housing disposed at an outer surface of the lower removable insert body; a primary lower coil disposed around the bore of the one or more well tree tubing sections in a first cavity of the lower coil assembly housing; and a secondary lower coil disposed around the bore of the one or more well tree tubing sections in a second cavity of the lower coil assembly housing; one or more seals disposed at an inner surface of the upper removable insert body and the lower removable insert body, the one or more seals providing a pressure seal to the joint; and wherein one of the upper coil assembly or the lower coil assembly detects at least one ferrous object disposed within the bore of the one or more well tree tubing sections.

Clause 9. The seal pocket detection system of clause 8, wherein the upper seal pocket detection assembly has a higher electromagnetic detection sensitivity than the lower seal pocket detection assembly.

Clause 10. The seal pocket detection system of any of clause 8 or clause 9, wherein the upper coil assembly and the lower coil assembly are disposed in a series along the bore of the one or more well tree tubing sections to thereby monitor a direction of the at least one ferrous object.

Clause 11. The seal pocket detection system of any of clause 8 through clause 10, wherein the upper seal pocket detection assembly is configured to operate actively by applying electrical power to the primary upper coil and measuring an electromagnetic field using the secondary upper coil.

Clause 12. The seal pocket detection system of any of clause 8 through clause 11, wherein the upper seal pocket detection assembly is configured to operate passively to detect a magnetic field associated with the at least one ferrous object.

Clause 13. The seal pocket detection system of any of clause 8 through clause 12, wherein the upper seal pocket detection assembly and the lower seal pocket detection assembly are disposed within a single pressure containing body of the joint.

Clause 14. The seal pocket detection system of any of clause 8 through clause 13, wherein the joint comprises a cross-flow connection of the one or more well tree tubing sections and the upper removable insert body and the lower removable insert body are disposed adjacent to the cross-flow connection.

Clause 15. A well tubing system comprising: a plurality of well tubing sections; a plurality of joints, each joint of the plurality of joints connecting a respective pair of tubing sections of the plurality of tubing sections; and a plurality of seal pocket detection assemblies, each seal pocket detection assembly of the plurality of seal pocket detection assemblies disposed at a respective joint of the plurality of joints and comprising: a removable insert body; one or more seals disposed at an inner surface of the removable insert body, the one or more seals providing a pressure seal to the respective joint; and a coil assembly comprising: a coil assembly housing disposed at an outer surface of the removable insert body; and at least one coil disposed around a bore of the respective pair of tubing sections in a cavity of the coil assembly housing, wherein the at least one coil produces an electromagnetic field within the bore of the respective pair of tubing sections, wherein the coil assembly detects a ferrous object disposed within the bore of the respective pair of tubing sections based on a change to the electromagnetic field associated with the ferrous object passing through the electromagnetic field.

Clause 16. The well tubing system of clause 15, further comprising: a plurality of clamps, each clamp of the plurality of clamps disposed around a respective joint to secure the respective pair of tubing sections together.

Clause 17. The well tubing system of any of clause 15 or clause 16, wherein the well tubing system is a hydraulic fracturing system.

Clause 18. The well tubing system of any of clause 15 through clause 17, further comprising: one or more valves associated with the plurality of tubing sections, wherein the one or more valves are adjusted in response to the coil assembly detecting the ferrous object.

Clause 19. The well tubing system of any of clause 15 through clause 18, further comprising: a cable routing port comprising a cable routing opening for receiving one or more cables within a hub of at least one of the plurality of tubing sections.

Clause 20. The well tubing system of any of clause 15 through clause 19, further comprising: a test port comprising a test opening within the hub of at least one of the plurality of tubing sections.

Although the invention has been described with reference to the embodiments illustrated in the attached drawing figures, it is noted that equivalents may be employed and substitutions made herein without departing from the scope of the invention as recited in the claims.

Having thus described various embodiments of the invention, what is claimed as new and desired to be protected by Letters Patent includes the following: