WO2019142024A1

WO2019142024A1 - Intelligent self-control rotary steerable

Info

Publication number: WO2019142024A1
Application number: PCT/IB2018/052469
Authority: WO
Inventors: Keivan KOHZADI
Original assignee: Kohzadi Keivan
Priority date: 2018-01-19
Filing date: 2018-04-09
Publication date: 2019-07-25

Abstract

While drilling directional and horizontal oil and gas wells, there are two methods for orienting the well in the predefined trajectory and, finally, hitting underground targets: The first is to use down-hole motors along with adjustable bent housing. The second method is to apply Rotary Steerable System which is by far much more efficient than former one. In this invention the device commanding connection through the pressure code is cut or minimized from the surface and transferred to the bottom-hole tool. That is, before moving the tool into the well, the predetermined drilling path is given to the processor unit. Once tool is run into the well and after reading each inclination and Azimuth by accelerometers and gyroscope sensors while drilling/at each measured depth station embedded in Non-Rotating Sleeve, the device at each moment / measured depth station calculates required Toolface and side force magnitude to follow the plan.

Description

Title of Invention : Intelligent Self-Control Rotary Steerable

System

Technical Field

[0001] Technical field of the present invention relates to well drilling equipment

exploiting mechanical and electronic techniques among many others.

Background Art

[0002] Indeed, the idea of removing drilling in slide mode 1990s, which eventually led to the development of Rotary Steerable Systems. In RSSs, in fact, a command is sent from the operator to the surface software, to create a side force to drill in the toolface, then the software turns this command into oscillatory pressure code and sent it through the pressure pulse generator surface machine (automatic mode) or is being sent manually by the operator changes on flow rate of drilling mud pumps or through manually varying RPM values of Top Drive system.

[0003] Subsequently, bottom hole signals receiver receives from these codes (a set of expected or unexpected oscillations), if possible, after filtering the meaningful pressure oscillations through its bottom hole, it exert a side force/bit tilt into tools placed at the top of the drill bit from different mechanisms Point The bit or Push the bit and then well gets it desired direction.

[0004] So far, a small number of famous companies in Drilling Industry succeeded in developing RSS tools including Schlumberger, Halliburton, Baker Hughes, Weatherford and National Oilwell Varco. All of the above tools, by command from toolface, receive the side force from the surface and uses two mechanisms of two-point the bit or Push the bit to provide necessary force to drill ahead in pre determined well trajectory.

Summary of Invention

[0005] The solution for the present problem is that the device commanding

connection through the pressure code (or flow rate related code) is cut or minimized from the surface and transferred to the bottom hole tool. [0006] That is, before moving the tool into the well, the predetermined drilling path is given to the processor unit. Once tool is run into the well and after reading each inclination and Azimuth by accelerometers and gyroscope sensors while drilling/at each measured depth station (for example 10 or 30 meters) embedded in Non-Rotating Sleeve, the device at each moment / measured depth station calculates required Toolface and side force to follow the plan.

[0007] Then, by order, the electro-motor, pump, and solenoid valves applied for each of the three available jacks will determine the amount and length of time needed to open the arm.

[0008] The existing processor, after each reading of angles through existing written algorithms, is able to perform the project ahead and intelligently self-regulating, in case of need to increase or decrease the side power to increase Or reduce the side force, then calculate and then apply it. The tool operation method is explained in the "Explaining at least a practical Method" section.

Technical Problem

[0009] While drilling directional and horizontal oil and gas wells, there are two

methods for directing drill in the predefined path and, finally, targeting

underground targets:

[0010] The first is to use submersible positive displacement motors along with

Adjustable Kick off point. The second method is to apply Rotary Steerable System which is by far much more efficient (at the same time more expensive and sophisticated) than former one.

[0011] In aforementioned systems, intelligence and decision making are not from artificial intelligence and decision making and determining the fate of wells being drilled is performed by an experienced and knowledgeable expert known as Directional Driller and decisions are communicated from the surface to submersible system set and then implemented.

[0012] The most important drawback and problem in the first method is that rotating and steering well in inclination and azimuth of submersible target requires stopping drilling stand rotating from Rotary Table or Top Drive and drilling should be occurred in slide drilling mode. [0013] This drilling mode has many disadvantages, some of which are as following:

[0014] A - Increased risk of pipe stuck.

[0015] B - The lack of hole cleaning efficiency due to stationary mode of bottom hole assemblies.

[0016] C - Failure to drill Extended Reach Wells and 3D Complex Wells.

[0017] D - Drill Pipe buckling during drilling in slide mode which results in damage or fatigue, and ultimately reduces their lifespan. In the second case, there is essentially no major problem, and now in the world, most of Extended Reach Wells are drillable with such tools. Although they face some issues as follow:

[0018] E - It is very expensive

[0019] F - Manpower intervention in deciding on inclination, azimuth and amount of dogleg required to reach a well preplanned trajectory.

[0020] G - Transmission of pulses carrying encoded messages from the surface to the bottom hole receivers in some cases is not possible and, consequently, the operation is stopped.

Advantageous Effects of Invention

[0021] As it mentioned previously, there are only two applied methods to steer wells in the drilling industry as follow:

[0022] 1- To use down hole positive displacement motors along with Adjustable Kick off point.

[0023] 2- The second method is to apply Rotary Steerable System which is by far much more efficient (at the same time more expensive and sophisticated) than former one.

[0024] The main advantages and benefits of the present invention in comparison to former method:

[0025] A - Enhances drilling speed by removing drilling in slide mode.

[0026] B - Improving and uniformity of the weight transfer to the bit by removing drilling in slide mode. [0027] C - Improving hole cleaning and cutting transfer to the surface through permanent drill pipes rotation.

[0028] D - Increasing Horizontal Displacement in horizontal wells.

[0029] E - Allowing drilling 3D complex wells with High Directional Difficulty Index

[0030] F - Increasing the hole quality and prevent the Hole Enlargement in drilled area in rotating mode.

[0031] The main advantages and benefits of the present invention in comparison to latter method:

[0032] Solving problems and barriers for applying the command from the surface to the submersible advice: One of the most expensive, most sophisticated parts of current RSS systems is the downlinking of encoded messages, mainly due to pressure oscillations or fluid flow fluctuations.

[0033] Getting high-diversity messages and decoding code commands are mostly difficult by down hole processor systems. In fact, in the path of data transmission through the pressure code from the drilling fluid channel in the pipes, it is very uncertain. The reason for this is the inadvertent pressure pulses and noises of the system (not created by the surface manual or automatic pulse generation system).

[0034] Therefore, the down hole receiver in some cases receives these unwanted pressure pulses (or flow changes) codes along with encrypted pressure codes; in this case, or as a result of the inaudible nature of the pressure sequence, it is unable to receive and execute orders, or Decodes the code incorrectly and executes the unwanted command.

[0035] Due to the diversity and high number of codes required by the down hole tool, including magnitude (including 1 to 100% arm powers), and Toolface (0 to 360 degrees), the required force to orient, the number of codes in the case of Requirement must be decoded from the transmitter's level and processed by the processor, which, for example, is a particular kind of fluctuation of the pressure received from the surface, which means how much force is created and in which direction. [0036] Of course, if it was to be done carefully all the drilling angular work should be sent 360 * 100 modes (36000 commands). In other words, 36,000 command codes should be written, transmitted, compressed or fluctuated, and can be decoded by a down hole processor, which is completely impossible due to the uncertain space of pressure and flow flux in the well.

[0037] Therefore, the RSS toolkit usually has 0 to 360 degrees in 12 parts (each part has 30 degrees and the required strength of the arm is from 0 to 100 to 4, that is, there are actually 48 codes available. Instructions regarding the appearance of the instrument and the amount of force, in addition to the inaccuracy imposed by human decisions, itself leads to inaccuracy in the follow-up of the well

predetermined trajectory by the RSS system.

[0038] In the present invention, no pressure code is transmitted from the surface to the instrument, and only an announcing signal (announcing the MD increase to the predefined level for the device) is transferred from the surface to the device. And the down hole tool, because it does not deal with a large number of code (for decoding), and it is only necessary to receive a code or signal, the code can be transmitted through each transmission line (albeit of poor quality), capable of to get through the down hole tool.

[0039] Then the rest of the command line with the processor and its intelligent control system receives the down hole tool itself to the other parts of the tool to execute the too face command and the magnitude of the side force necessary for dogleg generation.

[0040] This issue of making intelligent and deleting code from the surface to the tool, in addition to increasing the speed of drilling through the disconnection of tool-to- surface, the probability of making wrong instructions and mismatching the actual well path with a pre-programmed path due to unsuccessful decoding as well as zero-risk human failure, as well as eliminating the limits of the command line for the instrument's appearance and the amount of force required.

[0041] Another advantage of the invention in comparison to other tools that use

rotary steerable system to make well azimuth, is that it is compatible with any M / LWD system from any manufacturer and brand. One of the weaknesses in RSS systems is that the brand's RSS tool must be used with the same M / LWD systems, for example, if the client needs the Halliburton Full Suit LWD tool, inevitably The RSS tool is the same as the manufacturer and does not have the power of choice, which is due to the interference of the downlinking RSS receiver with the other company's LWD transmitter tool.

[0042] Since the full suit LWD manufacturer are all RSS manufacturers, their M /

LWD transmitter system (Pulser) is same as Downlink code receiver system, called the Bi-Communicational Module. Therefore, the code for the RSS feed from above is incorrectly received by the LWD receiver and caused an error in the LWD tool.

[0043] This issue of the autonomy of the present invention to send code from above to get command code is one of its special advantages of the present invention. Another advantage is the ability to use this system in drilling wells suffering complete loss wells without mud return from annulus, as well as in wells that drilling fluid contains gas volumes (UBD, MPD while this is not possible in existing RSS systems.

Brief Description of Drawings

Fig.1

[0044] [Fig.1] An overview of all parts of invented device in interconnected manner.

Fig.2

[0045] [Fig.2] A cropped view of a portion near arms.

Fig.3

[0046] [Fig.3] A small view on one of the arms.

Description of Embodiments

[0047] Figure 1 : an overview of all parts of invented device in interconnected manner.

[0048] No. 1 : drill bit of claimed tool for this invention placed in well directly.

[0049] No. 2: Non-rotating sleeve section which embedded all arms, electromotor, pumps, electrical circuit packs (including measurement unit, processing unit and control unit) and batteries. [0050] No. 3: Bearings embed at the beginning and end of the Non-rotating sleeve.

[0051] No. 4: arms so that totally three arms are placed at a 120 _°.

[0052] No. 5: A set of batteries as well as electrical circuit packs that are fitted to the bottom of the Non-rotating sleeve.

[0053] No. 6: The rotary shaft which is connected from the bottom to the bit and from the top to Flex-Stabilizer and transfers drill pipes rotation to the bit.

[0054] No. 7: Flexible stabilizer, which in principle stabilizes the drilling stand near the claimed device's invention, and also makes it easier to generate dogleg in depth unit.

[0055] Figure 2: a cropped view of a portion near arms (No. 4 of Fig. 1).

[0056] No. 401 : arms driving Pistons.

[0057] No. 402: Oil pump.

[0058] No. 403: oil pumps Electromotor.

[0059] No. 404: The oil reservoir that reserves oil while all the pistons are in empty mode.

[0060] Figure 3: A small view on one of the arms

[0061] No. 401a: Two parallel pistons are displayed in the bottom of the arm.

[0062] No. 401b: the arm is embedded in hinged manner.

[0063] No. 401c: cylinder filling and discharging valves for each piston.

[0064] Figure 4: a cropped view on the battery pack as well as the electronic circuit pack.

[0065] No. 501 : The battery packs which is embedded in Non-rotating sleeve.

[0066] No. 502: A package of electronic circuits that are in parallel with the battery packs. This package includes measurement board, processing board and control board.

Industrial Applicability

[0067] The present invention is promising to drill, directional, vertical, horizontal, and three-dimensional complexes oil and gas wells, as well as water wells. In such a way that this device is mounted right after drill bit in the BHA, and according to inclination and azimuth program of the well, two steering and closed loop modes for wells build, drop and keep section and the keep section of the well through generation of side force to the bit prevents deviation of the predetermined path through bit.

[0068] In the steering mode, the pre-programmed well path is imported to the

processor unit of the import tool. And the processor's work, after each reading of the angles, calculates the actual path of the well and calculates the difference with the predetermined path at that depth and calculates the direction and magnitude of the side force needed to return to the planned path. In the method of implementation, among the computational methods of the well path, the Minimum Curvature Method is used and, as per client demand, the calculations can be easily converted to other methods, such as the Average angle, the Tangential Method, the Radios of Curvature, and so on.

[0069] In fact, in these computational methods, there are three inputs that the two inputs (Inclination and Azimuth) use through tools sensors, which are available for the processor in bottom hole, and the third input is the Measured Depth, through coding and a specific algorithm is sent to processor after drilling a given depth (e.g., ten meters).

[0070] As stated, of three of the inputs required to calculate the well path by the

down hole processor, the two inputs are measured by the sensors in the down hole tool and are available to the processor, one of the inputs remains unaltered, which is the same well depth at the point There is a measured value of Depth that there are two ways to reach the submersible processor:

[0071] 1. Measurement from inside the well without the need to send data from the surface to the down hole tool (Downlink): In this method, MD is measured by accelerometer sensors (through coding and sophisticated algorithms including Carmen filters). In this approach, changes in the gravity field measured by accelerometer sensors are sensed at any given moment, and MD is increased or decreased upon drilling stand movements. [0072] 2- Measuring the MD from the surface through pipe tally or through the Surface Depth Tracking and sending it to the down hole (Downlinking).

[0073] Here are a couple of ways to downlink:

[0074] A - Through creating a series of pressure pulses from the surface, either manually or by installing flow limiting tools on the way of mud flow from pump to standing pipe. After creating the coded pressure fluctuations, the down hole sensor receives these fluctuations and finds that the desired depth (i.e., 10 meters) has been added to the system, and this message is transferred to another processor.

[0075] B - Through creating a series of drilling fluids flow fluctuations. This is also done manually by adding or reducing flow through the passage of the fluid from the inlet pipe to stand pipe. Such flow changes are received by the down hole flow meter and the processor receives this command, which is, for example, another 10 meters is added to MD drilling.

[0076] C - Encoded and meaningful rotation of The BHA. In other words, creation of a predetermined oscillating RPM. This drilling rotation is received from the accelerometer sensor and the processor will found that it should add other 10- meters to MD in its calculations.

[0077] D - Axial movement (along the well axis) encoded and meaningful for the accelerometer sensor in the down hole tool.

[0078] E - Through creating a vibration / wave and receiving it by the down hole receiver. In fact, the down hole tool processor adds the desired area to the system after receiving any defined vibration / waveform sent from the surface. This vibration or wave can be caused by acoustic vibrations, radio frequency waves, or electromagnetic waves.

[0079] One method for sending wave to wells is the Mercury method. In this method, by installing an antenna on a String drilling at the top of the mast, the data is transmitted by a Carrier frequency. But since no transmission line is ideal, hence the use of a drill string as a transmission line also has a weakening, a wave return, and so on. [0080] As mentioned above, this transmission line has an Echo return wave due to connection points and impedance or other causes. This is why the OFDM method is used to compensate for this defect, which is named after the word“orthogonal frequency division multiplexing In this method, communication bandwidth is divided into several sub-bands channels. The Mercury has 1024 channels.

[0081] Also, the Mercury method uses W-CDMA, which is called the "Wideband Code-Division Multiple Access" words, and the DSSS, which acronym for words “direct-sequence spread spectrum ", is used. This modulation allows automatic matching with the channel change mode as well as the data rate and SNR in balancing mode.

[0082] F - Finally, but the easiest, most cost-effective and most reliable way is to use flow-switch. In this method, it is not necessary to determine flow, flow-switch or any other sensor that only disconnects or connects flow, it is enough to carry our very simple announcing code (adding MD) and transferring it the processor for the next steps.

[0083] It's worthy to note that to increase certainty the combination of carriers code mentioned above can be used, for example, "D" and "F" can be considered well.

In the present invention, the "F" method is used to send a message to add another depth unit (e.g. 10 meters) to the processor system. It should be noted that, since this invention has moved the decision from the surface into the well, the volume and variety of news / command codes has significantly decreased, thus requiring complex coding In order to differentiate the command code, it is possible to use the above methods independently to send the news of adding the depth unit to the processor system.

[0084] In this invention, in order to increase the certainty of receiving the message for the existing code (adding depth for calculations by the processor unit), both for sending the command code (redirection to any of the predetermined drill paths in During drilling, it occurs according to the requirements of the reservoir (very simple, deterministic and recognizable codes are used by the two processors' hubs and flow-switch sensors). [0085] While it's easy to use any of the other methods mentioned above. In essence, the point of the invention is to reduce the variety and volume of data required to send from the surface, which allows each of the above data transfer methods to be usable. The other point is to use a flow switch to recognize on or off situation of rig mud pumps which is the most reliable, easiest and cheapest way to receive a news signal which is adding MD interval to its processor calculations.

[0086] In fact, once signal is received adding a specific depth from drilling (e.g., 10 meters) from each of the above methods, the down hole processor has all three inputs for calculating the current coordinates of the well, and through the method Simplified mathematical coding in the tool, the true path of the well, the three- dimensional distance with the pre-planned trajectory, dogleg needed to return to the preset path and the toolface and magnitude of the side force required for returning wells to pre-planned coordinates and hitting underground geological targets.

[0087] The side force required to create a calculated dogleg is generated through a command line from the control unit to the electro-motors connected to embedded pumps, which ultimately pumps the oil to the cylinders that are placed under the arm, which in turn results in climbing arm, sticking and pushing them into the wall of the wellbore as a result of generation of a side force.

[0088] It should be noted that in case of a change in drilling path on part of operator (client) in the middle of the way, in order to prevent the trip out operation, which is time consuming and undesirable, number of predetermined drilling path coded programs can be stored in default of processor so that in case of changing plan, by a simple command code we can announce to device follow a new given plan.

[0089] At the same time as drilled wells have a part for generating dogleg and a part for retain and fix it, In order to save time and reduce the time it takes to send news codes to zero, only build, drop or turn section of MD code can be sent to device and that device can pre-set to change the path after reaching a given azimuth and inclination without calculation of well path by MD just by reading well azimuth and inclination in smart manner by opening arms and exerting force in opposite site.

Claims

[Claim 1] Intelligent Self-Control Rotary Steerable System which is consisted of following components: A - measurement unit; B - Processor unit; C - Control unit; D - Hydraulic pump; E - Electromotor; F - Solenoid valve; G - Hydraulic arms

[Claim 2] Well preplanned trajectory is given to bottom hole processor unit before moving tool to the well.

[Claim 3] According to claims number 2, other probable well preplanned trajectories are also given to the processing unit for possible replacement with the default trajectory.

[Claim 4] Once tool is run into the well and after reading each inclination and

Azimuth by accelerometers and gyroscope sensors while drilling/at each measured depth station embedded in Non-Rotating Sleeve, the device at each moment / measured depth station calculates required Tool face and side force magnitude to follow the plan.

[Claim 5] Based on claim 4, accelerometers and gyroscope sensors are embedded in Non-Rotating Sleeve.

[Claim 6] According to claim 4, having calculation of required side force, the control unit by order, the electro-motor, pump, and solenoid valves applied for each of the three available arms will determine the amount and length of time needed to open the arm and then generate dogleg in a desired toolface.

[Claim 7] Hydraulic arms are embedded mounted right after drill bit in BHA.

[Claim 8] Number of three hydraulic arms are placed on non-rotating sleeve which surrounds Rotary shaft, so that totally three arms are placed at a 120 _°.

[Claim 9] Given the claim 8, the aforementioned arms can create side force for generate dogleg in well up to 15_° in 30 meters depth and with Gravity or True North Toolface.

[Claim 10] The arms are fed and discharged by a piston charged by an electronic pump.

[Claim 11] As per claim 3, to inform addition of measured Depth to the processing unit, surface pumps get turned on-off with less complexity and sensing by flow switch embedded in the electronic control board.

[Claim 12] Considering claim 11 , in order to enhance reliability of receiving

messages by the processor unit, we can use both flow switch sensor and accelerometers (in order to receive the axial movement message of the drill pipe).

[Claim 13] As it can be seen in claim 2, message for changing path to one of the preplanned trajectories that had previously been entered into bottom hole processor unit is the simple and certain combination of codes that can easily be detected by the flow-switch and accelerometer sensors.

[Claim 14] Given claim 11 , as message sent from the surface has small size than other RSS systems, methods for calculating depth from bottom hole or sending from the surface can be used.