Perforation unit and perforation method

Abstract

A method and apparatus for controlling a perforating tool string using a perforating unit having a control board and a firing power supply. One embodiment includes a control system for controlling a detonator in a perforating gun string, the perforating gun string including a perforating unit, the perforating unit also including a software driven power supply, a control board coupled to the power supply, wherein the power supply is programmed to automatically output a specified amount of voltage / current for a specified time period within a specified depth window.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Application No. 63 / 134,281 filed on January 6, 2021 and U.S. Provisional Application No. 62 / 977,115 filed on February 14, 2020. Background Art

[0003] Current methods of perforating wellbores, particularly pumping down perforators in horizontal wells, combine a variety of complex operations involving multiple services and surface equipment independently operated by multiple human users. A cable unit is required to transport the perforating tool string downhole via a power cable and is controlled by a person via a winch control. The downhole perforating tool string includes a cable head for attachment to the cable, depth-related tools such as a casing collar locator (CCL) and / or a gamma ray (GR) detector, an optional directional sensor for indicating the position of the perforating gun in the wellbore, an optional tensioning tool for providing downhole tool tension, multiple perforating guns, and a setting tool for setting the plug. For horizontal wells, a manual pumping unit is required to pump fluid to push the perforating tool string through the lateral portion of the wellbore to the final desired measurement depth. A launch panel, typically operated by an individual within the cable unit, is required to communicate with and selectively power each perforating gun in the downhole perforating tool string. The acquisition system is typically operated by an individual within a cable unit and requires collecting and processing cable velocity, surface tension, and depth data from the winch system, and processing downhole tension, depth-related data signals (e.g., from casing collar locators and / or gamma ray detectors), and tool orientation data from downhole tools in order to visualize and record operations. One or more of the following processes need to be combined - pumping down the perforating tool string, conveying winch control, shooting power supply, and acquiring the perforating data into an automated and individually controlled entity called a perforating unit. The perforating unit as described herein reduces human errors that occur due to manual operation of the cable winch, pumping unit, acquisition system, and / or launching panel. Associated human errors have and may result in monetary losses due to downtime, damage, and / or abandonment of the well. Associated human errors have and may result in damage to equipment, the environment, and personnel, including loss of life. A perforating unit is a single unit or a system of compatible units designed to automate and control one or more of the following systems and processes: the surface pumping unit during down pumping operations, the winch system during down pumping and perforating operations, the data acquisition system during down pumping and perforating operations, and the firing power supply during perforating operations. Summary of the invention

[0004] Example embodiments may include a control system for controlling detonators in a perforating gun string, the control system comprising a perforating unit, the perforating unit further comprising a software driven power supply, a control board coupled to the power supply, wherein the power supply is programmed to automatically output a specified amount of voltage / current for a specified time period within a specified depth window.

[0005] Variations of the example embodiments may include a data acquisition system. It may include a winch controller. It may include electronic switch software programmed with user input for the number of downhole switches, triggers, perforation depth, depth-related offsets for each trigger, and automatic calculation of stop depths and ideal winch speeds to retrieve during an automated perforation process. It may include output voltages and durations that are preprogrammed based on selection of conventional detonator types used in downhole completion tools. It may include output voltages and durations based on igniting detonators in perforating guns. It may include output voltages and durations based on igniters in plug-setting tools. It may include a perforation panel automatically communicating with one or more downhole addressable switches, determining that the depth matches the perforation depth, and applying the appropriate electrical energy at the correct perforation depth. It may include a data acquisition system of the perforating unit to acquire, process and record data representing line speed data from the delivery winch system, depth data from the delivery winch system, surface tension from the delivery winch system, data representing pumping rate from the surface pumping unit, downhole tension from a downhole tool sensor, casing collar locator data from the downhole tool sensor, gamma ray data from the downhole tool sensor, and tool orientation from a downhole tool orientation sensor. It may include a winch controller that automatically responds to data acquired and processed by the data acquisition system of the perforating unit. It may include a perforating unit that controls the winch speed of the delivery unit during downward pumping. It may include a perforating unit that controls the pumping rate of a surface pumping unit that is used to cause fluid to flow downhole under pressure so as to push the downhole cable tool string laterally into the horizontal wellbore until a desired measurement depth is reached. It may include a pump controller. It may include a winch controller that monitors depth, line speed, pumping rate, and tool tension data from a data acquisition system of a perforating unit to automatically adjust the line speed of the winch system to maintain an optimal tool tension and a desired pumping rate. It may include an optimal tool tension calculated by a data acquisition system of the perforating unit based on pre-pumping down operation user input, downhole tool pressure ratings, minimum and maximum line speeds, minimum and maximum surface tensions, and cable head weakness ratings, such as maximum tool string tension. It may include inputting the desired pumping rate into the data acquisition system at increasing depths based on known well deviation measurements prior to a pumping down operation. It may include the optimal tool tension and the desired pumping rate being automatically adjusted by the perforating unit as a function of depth as the tool string is pumped into a horizontal well.

[0006] One exemplary embodiment may include a method for firing a downhole tool, including lowering the tool to a first predetermined distance in a wellbore, scanning the gun string, inputting operation parameters into a perforating unit, lowering the tool to a second predetermined wellbore depth, deactivating a pump at the second predetermined wellbore depth, stopping the tool at the second predetermined wellbore depth, raising the tool to a first predetermined perforating depth, calculating an optimal winch speed based on a shot distance and a desired firing time, firing the tool at the first predetermined perforating depth, wherein the perforating unit sends a command to a firing power source to fire, determining whether a shot at the first predetermined perforating depth was successful, and determining whether all shots have been fired.

[0007] Variations of the exemplary embodiments may include lowering the tool string downhole via a drawworks controller. It may include determining whether the tool is ready to be lowered. It may include collecting data using a downhole tool data source. The downhole tool data includes tool tension, data from a casing collar locator, data from a gamma ray tool, or the data includes data from a directional sensor. It may include collecting surface data, including tool depth or surface tension. It may include calculating line speed by data collection based on a surface drawworks data source. It may include collecting pumping rate data. It may include correlating data to determine the position of the tool string and the downhole speed of the tool string. It may include adjusting the drawworks speed to match a desired speed. It may include lowering the tool to a desired deviation. It may include managing the pump via a pump controller to achieve a desired tool tension. It may include adjusting the pump via the pump controller, and adjusting the drawworks via the drawworks controller to achieve a desired tool tension. The second predetermined depth may be a bottomhole depth. The pump controller may deactivate the pump at the second predetermined depth. Stopping the tool at the second predetermined depth may be performed by the drawworks controller. It may include selecting a fully automatic or semi-automatic perforation method. It may include setting a plug. It may include detecting firing and deactivating a firing power source. It may include preventing short circuiting after the tool fires a shot at a first predetermined perforation depth. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 A schematic diagram is shown showing a downhole perforating gun tool string on a wireline electrically connected to a perforating panel.

[0009] Figure 2 An operational flow chart of a perforating panel interfaced with a downhole perforating gun string is shown.

[0010] Figure 3 A diagram is shown representing a downhole perforating gun tool string having a casing collar locator, a gamma ray tool, and a directional tool on a cable electrically connected to a perforating panel and a data acquisition system. Figure 3The winch controller is a separate but compatible entity that may or may not be automatically controlled by the perforated panel.

[0011] Figure 4A and Figure 4B An operational flow chart of a perforating unit interfaced with a downhole perforating gun string is shown, the perforating unit having a perforating panel and a data acquisition system.

[0012] Figure 5 A diagram is shown representing a downhole perforating gun tool string having a casing collar locator, a gamma ray tool and a directional tool stringed on a cable electrically connected to a perforating unit having a launch panel, a data acquisition system and a drawworks controller.

[0013] Fig. 6A and Figure 6B An operational flow chart of a perforating unit is shown, the perforating unit being docked with a downhole perforating gun string, the perforating unit having an automatic firing panel, a data acquisition system and a drawworks controller.

[0014] Figure 7 A diagram is shown representing a downhole perforating gun tool string having a casing collar locator, a gamma ray tool, a downhole tension tool and a directional tool, a data acquisition system, a drawworks controller and a pump controller located on a cable electrically connected to a perforating unit having a perforating panel.

[0015] Fig. 8A , Figure 8B and Figure 8C An operational flow chart of a perforating unit is shown, the perforating unit being interfaced with a downhole perforating gun string, the perforating unit having a perforating panel, a data acquisition system, a drawworks controller and a pump controller. DETAILED DESCRIPTION

[0016] In the following description, certain terms are used for brevity, clarity and example. No unnecessary limitations are implied, and these terms are used for descriptive purposes only and are intended to be broadly interpreted. The different devices, systems and method steps described herein may be used alone or in combination with other devices, systems and method steps. It is contemplated that various equivalents, substitutes and modifications are possible within the scope of the appended claims.

[0017] Terms such as booster may include a small metal tube containing a secondary high explosive crimped onto the end of a detonating cord. Explosive assemblies are designed to provide reliable detonation transfer between perforating guns or other explosive devices and are often used as a backup explosive to ensure detonation.

[0018] A detonating cord is a cord containing a high explosive enclosed in a flexible casing, which is used to connect a detonator to a main high explosive, such as a shaped charge. This provides a very rapid detonation sequence that can be used to ignite multiple shaped charges simultaneously.

[0019] The detonator or initiator may include a device of a primary high explosive material for initiating a detonation sequence, the detonator or initiator including one or more shaped charges. Two conventional types may include an electric detonator and an impact detonator. The detonator may be referred to as an initiator. An electric detonator has a fuze material that burns when a high voltage is applied to initiate the main high explosive. An impact detonator contains abrasive particles and a primary high explosive in a sealed container that is activated by a striker. The strike of the striker is sufficient to initiate the impact sequence, which is then transmitted to the detonating cord.

[0020] Conventional perforation in a vertical well or unconventional perforation in a horizontal well utilizes any delivery method where the downhole tool is tethered to the winch system of the present invention via a power line. Although perforation is the primary application, the same invention and method can be applied to the operation of any well where downhole devices are activated at a determined depth by sending power along a power cable such as a cable. Examples other than perforation include: setting a plug, activating a cutter to cut casing, activating a cut-off tool or a loosening tool to release a stuck pipe, activating a detonator in a mud pump to dump cement, delivering a stimulation measure to one or more perforated areas, or activating any other downhole impact device.

[0021] A "firing panel" (also called a "shooting power supply" and "perforating panel" and "perforating unit") is a surface electronic power unit that is connected to a downhole delivery tool such as a line and supplies power to downhole completion tools, primarily to the perforating system. The power path from the firing panel at the surface to the detonator / initiator in the perforating gun is: VAC wall outlet - VDC firing panel - cable collector ring - cable - cable head contact - casing collar locator - electronic switch in the perforating gun - detonator in the perforating gun or igniter in the plug setting tool. Multiple perforating guns are connected in series below the CCL (casing collar locator). Each perforating gun contains electrical contacts or wires to connect the power path above to the electronic switch and detonator (initiator). Once the detonator is activated by the applied power, the explosion is transmitted to the detonating cord, which activates the shaped charge attached to the perforating gun.

[0022] The perforating process requires several steps to successfully perform a deep perforation utilizing the select-fire electronic switch in the perforating gun. First, the user must ensure that the perforator is in the correct downhole position as the cable is retrieved from the bottom hole depth by a winch and depth tracking system that is independent of the firing panel. While at depth, the user must send electronic commands to the downhole switch through the electronic switch software in order to address, arm, and prepare to fire. Once depth is reached, or approaching depth if firing while moving up, a two-handed procedure must be performed when firing each shot: (1) normally hold the spring-loaded trigger or press and hold a spring-loaded button (2) press and hold a separate spring-loaded button or turn the knob clockwise from hard left / stop (zero) (increasing voltage). The above actions must be performed within a relatively short time window (10 seconds-30 seconds) and may be further complicated if firing is performed while moving up the hole rapidly.

[0023] An exemplary embodiment of the perforating unit will allow the firing power supply and electronic switch software to be automated or semi-automated once started downhole during the perforating process. The perforating process that can be automated by the user includes: relevant depth acquisition to the electronic switch software and power panel, software input for checking the electronic switch for armor activation, and applying the necessary voltage for a sufficient amount of time to ignite the detonator. Prior to deployment or during a trip at a depth below 200 feet downhole, the user can power the perforating unit and select "automatic mode" in the perforating unit, and then set the automation process by entering the number of electronic switches, the perforation depth of each gun, the depth correlation offset, and the stop depth. When the perforating tool string is at the bottom hole depth, the user begins to retract the tool string up the hole at the winch speed calculated by the perforating unit. The user will start the perforating process with a simple two-handed operation, such as holding down a keyboard button while pressing a spring-loaded button on the perforating unit. This starts the automation sequence. As the downhole tool string approaches each perforation depth, the perforating unit will autonomously address the switch of each gun and apply power to fire each gun at the precise perforation depth input in a pre-programmed sequence during setup. Once the perforation process begins, the user does not have to "do" anything. The user can focus on winch speed and other non-perforating operations. As an alternative, the user must take two actions within each perforation depth window (+ / - x feet within each perforation depth) in order for the power supply to automatically output shooting power. Two-handed operation can be to hold the keyboard button while pressing the spring-loaded button on the perforating unit. The perforating unit also has a standard manual mode capability. If any problems occur, the system will warn the user to stop and return to manual mode.

[0024] Figure 1An exemplary embodiment is disclosed in the invention, which shows a perforating unit 100. The perforating unit 100 includes an automatic firing panel 102 powered by an AC power source. The AC power source supplies power to a firing power source 103 connected to a control board 104. The control board 104 is connected to a computer 101 via a USB connection or a wireless connection. The control board 104 is connected to a panel output, which is connected to a cable 105. The cable 105 is connected to a downhole tool, which includes one or more electronic switches 106 and 107, for example, each of which is connected to a detonator / initiation 108 and 109, respectively. The perforating unit 100 can detect the ignition of the detonator / initiation 108 and / or 109 and automatically disconnect the ignition voltage provided by the firing power source 103, thereby preventing a short circuit caused by wellbore fluid entering the downhole tool after detonation. The mitigation of the short circuit protects the cable 105 and other electronic devices connected to the cable.

[0025] Figure 2An exemplary embodiment is disclosed, which shows a flow chart of a perforating unit 200 including an automatic firing panel. The program starts, step 201, and the tool is lowered to 200 feet, step 202. The perforating unit 200 then scans the gun string and enters the operation parameters, step 203. The perforating unit 200 then determines whether the tool begins to be lowered into the well, step 204. If the tool is not ready to be lowered, the user will complete any other processes, step 205, and then determine whether the tool begins to be lowered into the well, step 204. If the tool is ready to be lowered, the user lowers the tool string by winch or other selection, step 206. The descent speed is queried, step 207, and if the descent speed is not the desired speed, the user adjusts the winch speed, step 208. If the tool is descending at the desired speed, the tool will continue to descend until the bottom depth is reached, step 209. When the tool reaches the desired depth, the user stops the tool from being lowered, step 210. The user then selects a fully automatic or semi-automatic perforating method, step 211. The program calculates the optimal winch speed based on the shot distance and the required firing time, step 212. The perforating unit 200 then receives a two-hand operation from the user to start, step 213. The plug is set if applicable, step 214. The tool is raised by the winch controlled by the user, step 215. The tool speed is evaluated, step 216, and the winch speed is adjusted by the user as needed, step 217. The perforating unit 200 collects the tool depth from an external process, step 218. When the program determines that the tool is approaching the perforating depth, step 219, the perforating unit 200 sends a command to the power supply to initiate the firing, step 220. The perforating unit 200 then determines whether the firing was successful, step 221. If not, the user is notified of any problems, step 223. If successful, the program determines whether all shots have been fired, step 222. If all shots have been fired, the program notifies the user of completion, step 224. If all shots are not fired, the program will return to querying the tool for speed and depth to fire the next shot.

[0026] An exemplary embodiment of a perforating unit can automate and control the firing power supply and data acquisition during the perforating process. Operation will not require a separate stand-alone data acquisition system. The data acquisition system of the perforating unit acquires, processes, interprets and records one or more of the following data groups: depth data from the drawworks unit, line speed data from the drawworks unit, surface tension data from the drawworks unit, tension data from sensors on the downhole tool string, directional sensor data from the downhole tool string, and depth-related data from sensors in the downhole tool string, the sensor being a detector such as a casing collar locator (CCL) or a gamma ray (GR). One or more processed data groups are monitored by the perforating unit so that once the automatic mode is activated on the perforating unit, the firing power supply and electronic switch software respond automatically without any user input.

[0027] The perforation process that can be automated by the user includes: relevant depth acquisition to the electronic switch software and power panel, software input of the electronic switch for checking armor activation, and applying the necessary voltage for a sufficient amount of time to ignite the detonator. Before deployment or during a trip at a depth below 200 feet downhole, the user can power the perforating unit and select "automatic mode" in the perforating unit, and then set up the automation process by entering the number of electronic switches, the perforation depth of each gun, the depth correlation offset and the stop depth. When the perforating tool string is at the bottom hole depth, the user begins to retract the tool string up the hole at the winch speed calculated by the perforating unit. The user will start the perforation process with a simple two-hand operation, such as holding down a keyboard button while pressing a spring-loaded button on the perforating unit. This starts the automation sequence. As the downhole tool string approaches each perforation depth, the perforating unit will autonomously address the switch of each gun and apply power to fire each gun at the precise perforation depth input in a pre-programmed sequence during setup. Once the perforation process begins, the user does not have to "do" anything. The user can focus on the winch speed and other non-perforating operations. As an alternative, the user must take two actions within each shot depth window (+ / - x feet within each shot depth) in order for the power supply to automatically output shot power. Two-hand operation can be holding the keyboard button while pressing the spring loaded button on the perforating unit. The perforating unit also has a standard manual mode capability. If any problems occur, the system will warn the user to stop and return to manual mode.

[0028] Figure 3An exemplary embodiment is disclosed in the invention, which shows a perforating unit 300 with a perforating panel and a data acquisition system. The perforating unit 300 includes an automatic firing panel 302 powered by an AC power supply. The AC power supplies power to a firing power supply 303, which is coupled to a control board 304 including data acquisition. The control board 304 is coupled to a computer 301 via a USB connection or a wireless connection. The control board 304 is coupled to a panel output, which is coupled to a cable 305. The cable 305 is coupled to a downhole tool, which may include one or more of a downhole tension tool 320, a casing collar locator (CCL) 310, a gamma ray tool 311, a directional tool 312, and at least one electronic switch 306, which is coupled to at least one detonator / initiator 308. The control board 304 acquires one or more of cable depth and cable surface tension data from a winch controller 313, which is controlled by a separate winch motor 314. The cable speed is calculated by the control board 304 data acquisition system, which is based on data from the winch controller 313. The winch controller 313 is manually adjusted by the user to control the winch motor 314. The perforating unit 300 can detect the firing of the detonator / initator 308 and automatically disconnect the firing voltage provided by the firing power supply 303, thereby preventing a short circuit caused by wellbore fluid entering the downhole tool after the detonation. The mitigation of the short circuit protects the cable 305 and other electronic devices connected to the cable.

[0029] Figure 4A An exemplary embodiment is disclosed, which shows a flow chart of a perforating unit 400 with a perforating panel and a data acquisition system. The program starts, step 401, and the tool is lowered to 200 feet, step 402. The perforating unit 400 scans the gun string and the user enters the operation parameters, step 403. The user then decides whether to start lowering the tool into the well, step 404. If the tool is not ready to be lowered, the user will complete any other processes, step 405, and then decide whether to start lowering the tool into the well, step 404. If the tool is ready to be lowered, the user lowers the tool string by winch or other options, step 406.

[0030] The perforating unit 400 will collect data 407 using downhole tool data sources such as tool tension 430, casing collar locator 431, gamma ray tool 432, and directional sensor 433. The perforating unit 400 will collect data 407 using surface winch data including line speed 440, tool depth 441, and surface tension 442. All depth data are correlated as step 408.

[0031] The descent speed is queried, step 409, and if the descent speed is not the desired speed, the user adjusts the winch speed, step 410. If the tool is descending at the desired speed, the tool will continue until the tool reaches the bottom depth, step 411. When the tool reaches the desired depth, the user stops the tool from descending, step 412. The user then selects a fully automatic or semi-automatic drilling method, step 413.

[0032] The procedure is described in Figure 4B 414. When the user retrieves the tool string via the winch control, the program calculates the optimal winch speed based on the shot distance and the required firing time, step 414. The perforating unit 400 then receives a two-hand operation from the user to start the firing operation, step 415. The plug is set if applicable, step 416. The tool is raised via the winch controlled by the user, step 417. The program monitors the winch and tension data, step 418. The cutter speed is evaluated in step 419 and adjusted as needed in step 420. The perforating unit 400 determines if the tool is approaching the perforating depth, step 421. When the program determines that the tool is approaching the perforating depth, step 421, the perforating unit 400 sends a command to the power supply to start firing, step 422. The perforating unit 400 then determines if the firing was successful, step 423. If not, the user is notified of any problems, step 425. If successful, the program determines if all shots have been fired, step 424. If all shots have been fired, the program notifies the user of completion, step 426. If not all shots have been fired, the program will return to querying the tool speed and depth to fire the next shot.

[0033] An exemplary embodiment of a perforating unit can automate and control the firing power supply, data acquisition system, and winch controller during tool deployment into a well, tool retrieval from a well, and the perforating process. The data acquisition system of the perforating unit acquires, processes, interprets, and records one or more of the following data sets: depth data from the winch unit, line speed data from the winch unit, surface tension data from the winch unit, tension data from sensors on a downhole tool string, directional sensor data from the downhole tool string, and depth-related data from sensors in the downhole tool string (such as a casing collar locator (CCL) or a gamma ray (GR) detector). The perforating unit monitors one or more data sets so that once the automatic mode is activated on the perforating unit, one or more of the winch controller, firing power supply, and electronic switch software respond automatically without any user input. The processes that can be automated by the user include: deploying and retracting the perforating tool string by winch at a depth of less than 200 feet, associating depth acquisition with the electronic switch software and power panel, inputting the software to check the armor start electronic switch, and applying the necessary voltage for a sufficient amount of time to ignite the initiator. The perforating tool string is deployed into the wellbore to a depth of less than 200 feet before the perforating unit is powered on. Prior to descending into the well or during a downhole trip below 200 feet, the user can select "Auto Mode" in the perforating unit and then set up the automation process by entering the total depth, minimum and maximum line speed, minimum and maximum surface tension, number of electronic switches, depth of perforation per gun, depth-related offset, and depth of each stop. During descent into the wellbore, no surface pumping is required to assist the penetration of the tool to total depth, and the data acquisition portion of the perforating unit acquires and interprets data for depth-related. Line depth, line speed, and surface tension are collected from the drawworks unit and displayed on the graphical user interface (GUI) of the main perforating unit. Depth-related data is acquired from sensors in the downhole tool string, such as a casing collar locator (CCL) or a gamma ray (GR) detector, and then processed and displayed on the perforating unit GUI. The perforating unit uses data from the data acquisition system to control the speed of the drawworks during descent, and the perforating unit automatically stops once the total depth is reached according to the pre-set job settings. At any point in time, the user can exit "Automatic Mode" to manually control the winch system.

[0034] For both vertical and horizontal completions, the perforation process begins during the ascent to the wellbore. Once the total depth is reached, the perforation unit winch control automatically retracts the tool string up the hole at a winch speed calculated by the perforation unit based on user input during job setup. The user will activate the perforation system with a simple two-hand operation, such as pressing a spring-loaded button on the perforation unit while holding down a keyboard button. This initiates the firing power automation sequence. As the downhole tool string autonomously approaches each perforation depth, the perforation unit will autonomously address the switches for each gun, armor, and apply power to fire each gun at the precise perforation depth input in a pre-programmed sequence during setup. The user does not have to "do" anything after the perforation process begins. As an alternative, the user must take two actions within each perforation depth window (+ / - x feet within each perforation depth) in order for the power supply to automatically output firing power. The two-hand operation can be to hold the keyboard button while pressing the spring-loaded button on the perforation unit. The perforation unit also has a standard manual mode capability. If any problems arise, the system will warn the user to stop and return to manual mode.

[0035] The perforating unit will monitor winch speed and surface and / or downhole tension to safely return the tool string to the surface and stop at 200 ft. The perforating unit will return to manual mode where the winch must be manually controlled until returning to the surface.

[0036] Figure 5 An exemplary embodiment is disclosed in the Figure 5 showing a perforating unit 500 having a perforating panel, a data acquisition system, and a winch controller. The perforating unit 500 includes a perforating panel 502 powered by an AC power source. The AC power source supplies power to a shooting power source 503 connected to a control board 504 that performs data acquisition. The control board 504 is connected to a computer 501 via a USB connection or a wireless connection. The control board 504 is connected to a panel output, which is connected to a cable 505. The cable 505 is connected to a downhole tool, which may include one or more of a downhole tension tool 520, a casing collar locator (CCL) 510, a gamma ray tool 511, a directional tool 512, and at least one electronic switch 506, which is connected to at least one detonator / initiator 508. The control board 504 is connected to a winch controller 513 that controls a winch motor 514. The winch controller 513 depends on the cable depth data, cable surface tension data and winch control signal feedback when sending commands to the winch motor 514. The perforating unit 500 can detect the ignition of the detonator / initiator 508 and automatically disconnect the ignition voltage provided by the shooting power supply 503, thereby preventing a short circuit caused by wellbore fluid entering the downhole tool after detonation. The mitigation of the short circuit protects the cable 505 and other electronic devices connected to the cable.

[0037] Fig. 6A A flowchart of a perforating unit 600 of an exemplary embodiment is disclosed in the , which flowchart shows a perforating panel, a data acquisition system and a winch controller. The program starts, step 601, and the tool is lowered to 200 feet, step 602. Then, the perforating unit 600 scans the gun string, and the user enters the operation parameters, step 603. Then, the user decides whether to start lowering the tool into the well, step 604. If the tool is not ready to be lowered, the user will complete any other processes, step 605, and then decide whether to start lowering the tool into the well, step 604. If the tool is ready to be lowered, the perforating unit 600 lowers the tool string through the winch controller, step 606.

[0038] The perforating unit 600 collects data 607 from downhole tool data sources such as tool tension 630, casing collar locator 631, gamma ray tool 632, and directional sensor 633. The perforating unit 600 will collect data 607 from the surface winch data source including tool depth 641 and surface tension 642. Line speed 640 is calculated from data collection 607, which is based on data from the surface winch data source. All depth data is correlated, which is step 608.

[0039] The descent speed is queried, step 609, and if the descent speed is not the desired speed, the perforating unit 600 adjusts the winch speed, step 610. If the tool is descending at the desired speed, the tool will continue until the bottom hole depth is reached, step 611. When the tool reaches the desired depth, the program stops the tool from descending, step 612. The user then selects whether the perforating method is fully automatic or semi-automatic, step 613.

[0040] The procedure is described in Figure 6B614. The program calculates the optimum winch speed based on the shot distance and the desired firing time, step 615. The perforating unit 600 then accepts the user's two-hand operation to start, step 615. The plug is set if applicable, step 616. The tool is raised by the winch controlled by the winch controller, step 617. The program monitors the winch and tension data, step 618. The tool speed is evaluated, step 619. The tool speed is adjusted as needed, step 620. The program determines if the tool is approaching the perforating depth, step 621. When the program determines that the tool is approaching the perforating depth step 621, the perforating unit 600 sends a command to the power supply to start firing, step 622. The perforating unit 600 then determines if the firing was successful, step 623. If not, the user is notified of any problems, step 625. If successful, the program determines if all shots have been fired, step 624. If all shots have been fired, the program notifies the user of completion, step 626. If all shots have not been fired, the program will return to querying the tool speed and depth to fire the next shot.

[0041] For horizontal wells, a manual pumping unit is required to pump fluid to push the perforating tool string through the lateral portion of the wellbore to the final desired measured depth. During the downward pumping process, the user controlling the drawworks must also actively monitor and respond to the tension on the downhole tool string caused by the pumping rate of the surface pumping unit. During the downward pumping process, the user operating the pump controller must actively monitor and respond to the line speed and tool string tension.

[0042] An exemplary embodiment of a perforating unit can automate and control a firing power supply, a data acquisition system, a winch controller, and a pump controller during deployment of the tool into a well, retrieval of the tool from the well, and during the perforating process. The data acquisition system of the perforating unit acquires, processes, interprets, and records one or more of the following data sets: pumping rate from a surface pumping unit, depth data from a winch unit, line speed data from a winch unit, surface tension data from a winch unit, tension data from a sensor on a downhole tool string, directional sensor data from a downhole tool string, and depth-related data from a sensor in the downhole tool string such as a casing collar locator (CCL) or a gamma ray (GR) detector. The perforating unit monitors one or more data sets so that once an automatic mode is activated on the perforating unit, one or more of the pump controller, winch controller, firing power supply, and electronic switch software respond automatically without any user input. The processes that can be automated by the user include: pumping rate of a surface pumping unit, deployment and retrieval of a perforating tool string by a winch at depths below 200 feet. The depth acquisition is linked to the electronic switch software and power panel, the software is input to check the armor start electronic switch, and apply the necessary voltage for a sufficient amount of time to ignite the initiator.

[0043] The perforating tool string is deployed into the wellbore to a depth of less than 200 feet before the perforating unit is powered on. Prior to descending into the well or during a downhole trip below 200 feet, the user can select "Auto Mode" in the perforating unit and then set up the automation process by entering the cable head weakness (maximum downhole tension), total depth, minimum and maximum line speed, minimum and maximum surface tension, number of electronic switches, depth of perforation per gun, depth-related offset, and depth of each stop. During descent into the lateral portion of the horizontal wellbore, which requires surface pumping to assist the tool string in reaching total depth, the data acquisition portion of the perforating unit acquires and interprets data for depth correlation, winch control, and pump control. Line depth, line speed, and surface tension are collected from the winch unit and displayed on the graphical user interface (GUI) of the main perforating unit. Depth-related data is acquired from sensors in the downhole tool string, such as a casing collar locator (CCL) or a gamma ray (GR) detector, and then processed and displayed on the perforating unit GUI. Pumping rate is acquired from the pump controller and displayed on the perforating unit GUI.

[0044] Once the automatic mode is activated, the winch controller of the perforating unit monitors the depth, line speed, pumping rate and tool tension data from the data acquisition system of the perforating unit to automatically adjust the line speed of the winch system to maintain the optimal tool tension and the ideal pumping rate. At the same time, the pump controller of the perforating unit monitors the depth, line speed, pumping rate and tool tension data from the data acquisition system of the perforating unit to automatically adjust the pumping rate of the surface pumping unit to maintain the optimal tool tension and the ideal pumping rate. The optimal tool tension is calculated through data acquisition based on the pre-down pumping operation user input-downhole tool pressure rating, minimum and maximum line speed, minimum and maximum surface tension and cable head weakness rating. The ideal pumping rate is the user input of the pre-down pumping operation into the data acquisition at increasing depths based on the known well deviation measurement. When the tool string is pumped into the horizontal well, the optimal tool tension and the ideal pumping rate are automatically adjusted according to the depth through data acquisition. At any point in time, the user can exit the "automatic mode" to manually control the winch system. When the total depth is detected by the data acquisition system, the perforating unit will first stop the pumping unit and then the drawworks so that the downhole tool string stops at the total depth input during job setup.

[0045] For both vertical and horizontal completions, the perforation process begins during the ascent to the wellbore. Once the total depth is reached, the perforation unit winch control automatically retracts the tool string up the hole at a winch speed calculated by the perforation unit based on user input during job setup. The user will activate the perforation system with a simple two-hand operation, such as pressing a spring-loaded button on the perforation unit while holding down a keyboard button. This initiates the firing power automation sequence. As the downhole tool string autonomously approaches each perforation depth, the perforation unit will autonomously address the switches for each gun, armor, and apply power to fire each gun at the precise perforation depth input in a pre-programmed sequence during setup. The user does not have to "do" anything after the perforation process begins. As an alternative, the user must take two actions within each perforation depth window (+ / - x feet within each perforation depth) in order for the power supply to automatically output firing power. The two-hand operation can be to hold the keyboard button while pressing the spring-loaded button on the perforation unit. The perforation unit also has a standard manual mode capability. If any problems arise, the system will warn the user to stop and return to manual mode.

[0046] The perforating unit will monitor winch speed and surface and / or downhole tension to safely return the tool string to the surface and stop at 200 ft. The perforating unit will return to manual mode where the winch must be manually controlled until returning to the surface.

[0047] Figure 7An exemplary embodiment is disclosed in the invention, which shows a perforating unit 700, which includes a perforating panel, a data acquisition system, a winch controller and a pump controller. The perforating unit 700 includes an automatic firing panel 702 powered by an AC power supply. The AC power supplies power to a firing power supply 703 connected to a control board 704 that performs data acquisition. The control board 704 is connected to a computer 701 through a USB connection or a wireless connection. The control board 704 is connected to a panel output, which is connected to a cable 705. The cable 705 is connected to a downhole tool string, which includes a downhole tension tool 720 and one or more of a casing collar locator (CCL) 710, a gamma ray tool 711, a directional tool 712 and at least one electronic switch 706, which is connected to at least one detonator / initiator 708. The control board 704 is connected to a winch controller 713 that controls a winch motor 714. The winch controller 713 depends on the cable depth data, the cable surface tension data, and the winch control signal feedback when sending commands to the winch motor 714. The control board 704 is coupled to a pump controller 715. The pump controller 715 uses a combination of the pressure data, the flow rate data, and the pump control signal feedback to control the pump 716. The perforating unit 700 can detect the firing of the detonator / initator 708 and automatically disconnect the firing voltage provided by the firing power supply 703, thereby preventing a short circuit caused by wellbore fluid entering the downhole tool after the detonation. The mitigation of the short circuit protects the cable 705 and also protects other electronic devices coupled to the cable.

[0048] Fig. 8A An exemplary embodiment is disclosed, which shows a flow chart of a perforating unit 800. The program starts, step 801. The tool is lowered to 200 feet, step 802. The perforating unit 800 then scans the gun string and the user enters the operation parameters, step 803. The user then decides whether to start lowering the tool into the well, step 804. If the tool is not ready to be lowered, the user will complete any other processes, step 805, and then decide whether to start lowering the tool into the well, step 804. If the tool is ready to be lowered, the perforating unit 800 lowers the tool string through the winch controller, step 806.

[0049] The perforating unit 800 will collect data 807 using downhole tool data sources such as tool tension 830, casing collar locator 831, gamma ray tool 832, and directional sensor 833. The perforating unit 800 collects data 807 using surface winch data including surface winch data of tool depth 841 and surface tension 842. Based on the surface winch data source, the line velocity 840 is calculated from the data collection 807. The perforating unit 800 will collect data including pumping rate 834. All depth data is correlated, step 808, to determine the position of the tool string and the downhole velocity of the tool string.

[0050] The speed of descent is queried at step 809, and if the descent is not at the desired speed, the perforating unit 800 adjusts the drawworks speed at step 810. If the tool is descending at the desired speed, the tool will continue until the desired well deviation is reached at step 811.

[0051] The procedure is described in Figure 8B The perforating unit 800 activates the pump via the pump controller, step 850. The perforating unit 800 determines if the tool tension is within the desired range, step 851. If the tool tension is not within the desired range, the perforating unit 800 will adjust the pump and / or the winch via the appropriate winch controller or pump controller, step 852. The perforating unit 800 will then determine when the tool is approaching bottom hole depth, step 853. Once the program determines that the tool is approaching bottom hole depth, the perforating unit 800 deactivates the pump via the pump controller, step 854. The perforating unit 800 then determines if the tool has reached bottom hole depth, step 855. If not, the panel will adjust the winch speed via the winch controller to allow the tool to reach bottom hole depth, step 856.

[0052] When the tool reaches the bottom depth, the perforating unit 800 stops descending through the winch controller, which is step 812. Then, the user selects whether the perforating method is fully automatic or semi-automatic, which is step 813.

[0053] The procedure is described in Figure 8C814. The program calculates the optimum winch speed based on the shot distance and the desired firing time, step 815. The perforating unit 800 then accepts the user's two-hand operation to start, step 815. The plug is set if applicable, step 816. The tool is raised by the winch controlled by the winch controller, step 817. The program monitors the winch and tension data, step 818. The tool speed is evaluated, step 819, and adjusted as needed, step 820. The program determines if the tool is approaching the perforating depth, step 821. When the program determines that the tool is approaching the perforating depth, step 821, the perforating unit 800 sends a command to the power supply to start firing, step 822. The perforating unit 800 then determines if the blast was successful, step 823. If not, the user is notified of any problems, step 825. If successful, the program determines if all shots have been fired, step 824. If all shots have been fired, the program notifies the user of completion, step 826. If all shots have not been fired, the program will return to querying the tool speed and depth to fire the next shot.

[0054] Although the present invention has been described according to the detailed embodiments, it should be understood that this is merely illustrative and the present invention is not necessarily limited thereto. For example, terms such as upper and lower or top and bottom can be replaced by wellhead and downhole, respectively. Top and bottom can be left and right, respectively. Uphole and downhole can be shown as left and right, respectively, or as top and bottom, respectively, in the figure. Typically, downhole tools initially enter the borehole with a vertical orientation, but the orientation of the tool may change because some boreholes are ultimately horizontal. In this case, downhole, lower or bottom generally refers to a component in the tool string that enters the wellbore before the component referred to as uphole, upper or top, relatively speaking. The first housing and the second housing can be the top housing and the bottom housing, respectively. In a gun string such as described herein, the first gun can be an uphole gun or a downhole gun, the same as the second gun, and the uphole or downhole references can be interchanged because they are only used to describe the positional relationship of various components. Terms such as wellbore, borehole, well, exploration hole, oil well and other alternatives can be used synonymously. Terms such as tool string, tool, perforating gun string, gun string, or downhole tool, as well as other alternatives, may be used synonymously. Alternative embodiments and operating techniques will become apparent to those of ordinary skill in the art in light of this disclosure. Therefore, modifications to the present invention are contemplated without departing from the spirit of the claimed invention.

Claims

1. A control system for controlling a detonator in a perforating gun tool string, comprising: a perforating unit further comprising a perforating panel, a software driven power supply, a control board coupled to the power supply, wherein the power supply is programmed to automatically output a specified amount of voltage / current for a specified time period within a specified depth window without user operation; and electronic switch software, wherein the electronic switch software is programmed with user input for the number of downhole switches, actuators, perforation depths, depth-related offsets for each actuator, and automatic calculation of perforation stop depths and ideal winch speeds for retrieval during an automated perforation process; Therein, the perforation panel of the perforation unit automatically communicates with one or more downhole addressable switches to determine the depth and match the perforation depth, and apply appropriate electrical energy at the correct perforation depth.

2. The control system according to claim 1 further comprises a data acquisition system.

3. The control system of claim 2 further comprising a winch controller.

4. The control system according to claim 1, wherein: The output voltage and duration are pre-programmed based on a selection of conventional initiator types used in downhole completion tools.

5. The control system according to claim 2, wherein: The data acquisition system of the perforating unit acquires, processes and records data representing the line speed from the transport winch system, the depth data from the transport winch system, the surface tension data from the transport winch system, the pumping rate data from the surface pump unit, the downhole tension data from the downhole tool sensor, the casing coupling locator data from the downhole tool sensor, the gamma ray data from the downhole tool sensor and the tool orientation data from the downhole tool orientation sensor.

6. The control system according to claim 3, wherein: The winch controller automatically responds to data collected and processed by the data acquisition system of the perforating unit.

7. The control system according to claim 1, wherein: During the pumping down process, the perforating unit controls the winch speed of the delivery unit.

8. The control system according to claim 1, wherein: The perforating unit controls the pumping rate of a surface pumping unit for causing fluid to flow under pressure downhole to laterally lower the tool string into the horizontal wellbore until a desired measurement depth is reached.

9. The control system of claim 1 further comprising a pump controller.

10. The control system according to claim 3, wherein: The winch controller monitors depth, line speed, pump rate and tool tension data from the perforating unit's data acquisition system to automatically adjust the line speed of the winch system to maintain optimal tool tension and desired pump rate.

11. The control system according to claim 2, wherein: Optimum tool tension is calculated by the perforating unit's data acquisition system based on pre-pump-down operation user input, downhole tool pressure rating, minimum and maximum line speed, minimum and maximum surface tension, and cable head weakness rating.

12. The control system according to claim 3, wherein: Prior to the down pumping operation, the desired pumping rate is input into the data acquisition system at increasing depths based on known well deviation measurements.

13. The control system according to claim 1, wherein: When the tool string is pumped into a horizontal well, the optimum tool tension and the ideal pumping rate are automatically adjusted by the perforating unit according to the depth.

14. The control system according to claim 11, wherein: The cable head weakness is rated for maximum tool string tension.

15. A method for detonating a downhole tool, comprising: lowering the tool a first predetermined distance into the wellbore; Scanning gun string; Inputting the operation parameters into the perforation unit; lowering the tool to a second predetermined wellbore depth; deactivating the pump at the second predetermined wellbore depth; stopping the tool at the second predetermined wellbore depth; raising the tool to a first predetermined perforation depth; Calculates optimal winch speed based on shooting distance and desired ignition time; At the first predetermined perforation depth, the tool starts firing, wherein the perforating unit sends a command to a firing power source to start; determining whether the shot at the first predetermined perforation depth was successful; and Determine if all shots have been fired; Wherein, inputting the operation parameters into the perforation unit comprises: input for the number of downhole switches, triggers, perforation depths, depth-related offsets for each trigger, and automatic calculation of perforation stop depths and ideal winch speeds for retrieval during an automated perforation process; Before the tool starts firing at the first predetermined perforation depth, the method further comprises: The perforating unit automatically communicates with one or more downhole addressable switches to determine the depth and match the perforation depth, and applies the appropriate electrical energy at the correct perforation depth.

16. The method of claim 15, further comprising lowering the tool string downhole via a drawworks controller.

17. The method of claim 15, further comprising determining whether the tool is ready to be lowered.

18. The method of claim 15, further comprising acquiring data using a downhole tool data source.

19. The method according to claim 18, wherein: Downhole tool data includes tool tension.

20. The method according to claim 18, wherein: Downhole tool data includes data from casing collar locators.

21. The method according to claim 18, wherein: Downhole tool data includes data from gamma ray tools.

22. The method according to claim 18, wherein: Downhole tool data includes data from directional sensors.

23. The method of claim 15, further comprising collecting surface data.

24. The method according to claim 23, wherein: The surface data includes tool depth.

25. The method according to claim 23, wherein: The surface data includes surface tension.

26. The method of claim 15, further comprising calculating the line speed by data collection based on a surface winch data source.

27. The method of claim 15, further comprising collecting pumping rate data.

28. The method of claim 15, further comprising correlating data to determine a position of the tool string and a downhole velocity of the tool string.

29. The method of claim 15, further comprising adjusting a speed of the winch.

30. The method of claim 15, further comprising lowering the tool to a desired wellbore inclination.

31. The method of claim 15, further comprising managing the pump via a pump controller to achieve a desired tool tension.

32. The method of claim 15, further comprising adjusting the pump via a pump controller and adjusting the winch via a winch controller to achieve a desired tool tension.

33. The method of claim 15, wherein: The second predetermined wellbore depth is the bottom hole depth.

34. The method of claim 15, wherein: The pump controller deactivates the pump at a second predetermined wellbore depth.

35. The method of claim 15, wherein: Stopping the tool at a second predetermined wellbore depth is performed by a drawworks controller.

36. The method of claim 15, further comprising selecting a fully automatic or semi-automatic perforation method.

37. The method of claim 15, further comprising providing a plug.

38. The method of claim 15 further comprising detecting the launch and deactivating the firing power source.

39. The method of claim 15, further comprising detecting ignition of an initiator after the tool initiates firing at the first predetermined perforation depth and automatically disconnecting an ignition voltage provided by a firing power supply to prevent a short circuit.

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