Method and system for optimizing drilling parameters during ongoing drilling operations

Abstract

The invention relates to a method for optimizing at least one drilling parameter during an ongoing drilling process, the drilling being performed by a percussion drilling machine (105), the drilling machine (105) being set to drill at an operating point, the operating point of the drilling being determined by setting a plurality of control parameters. The method comprises determining a first plurality of drilling machine operating points (401a-d; 402b-d; 403c-d; 404a-d), the operating points (401a-d; 402b-d; 403c-d; 404a-d) being set by said plurality of control parameters. Furthermore, percussion drilling is performed at each of said first plurality of operating points (401a-d; 402b-d; 403c-d; 404a-d), and at least one final drilling parameter is evaluated for each of the plurality of operating points (401a-d; 402b-d; 403c-d; 404a-d). The method further comprises determining a new plurality of drilling machine operating points (401a-d; 402b-d; 403c-d; 404a-d) to be drilled based on said evaluation, and subsequently drilling the new plurality of drilling machine operating points (401a-d; 402b-d; 403c-d; 404a-d).

Description

Technical Field

[0001] This invention relates to percussion rock drilling, and more particularly to a method for optimizing at least one drilling parameter during the drilling process. The invention also relates to a system for implementing the method according to the invention, and a rock drilling rig including such a system. Background Technology

[0002] Rock drilling rigs have applications in many fields. For example, they can be used for tunnel excavation, open-pit mining, underground mining, rock reinforcement, and well drilling. They can also be used for drilling blasting holes, grouting holes, holes for installing rock anchors, water wells and other wells, piling, and foundation drilling. Therefore, rock drilling rigs have a wide range of uses.

[0003] The actual breaking of rock is typically performed by a drill bit that contacts the rock, which is usually connected to the drilling rig via a drill string. Drilling can be accomplished in various ways, and can be, for example, percussion, in which, for instance, the percussion element of the drilling rig—e.g., in the form of an impact piston—repeatedly strikes the drill bit by impacting the drill string that connects it to the drilling rig, transmitting shock pulses, i.e., stress waves, to the drill bit and further into the rock. Percussion drilling can be combined with rotary drilling to achieve drilling in which the ball teeth or inserts of the drill bit strike new rock with each stroke, thereby increasing drilling efficiency.

[0004] The drill bit can press against the rock with the help of the feed force during drilling to ensure that as much impact energy as possible is transferred from the impact device to the rock.

[0005] To achieve an effective percussion drilling process, it is crucial to set various drilling parameters in a manner that allows as much of the shock wave energy sensed by the impact element and entering the drill string as possible to be transferred into the rock for rock fracturing. In this way, effective rock fracturing can be achieved. If the shock wave energy transferred by the impact element is too low, this can negatively impact drilling productivity. Furthermore, harmful reflections may occur if the shock wave energy is too low relative to the force exerted by the drill string against the rock and / or too low to fracture the rock. This is also true when the shock wave contains more energy than is required to fracture the rock.

[0006] If the drill bit is not firmly pressed against the rock, energy can be reflected to undesirable levels and return to the drilling rig, potentially causing excessive wear or damage. The same applies if the drill string joints are not properly tightened. Summary of the Invention

[0007] The object of this invention is to provide a method and system for optimizing at least one drilling parameter during the drilling process.

[0008] According to the present invention, a method is provided for optimizing at least one drilling parameter during an ongoing drilling process. Drilling is performed by a percussion drilling machine. The drilling machine is configured to drill at an operating point, wherein the operating point is determined by setting a plurality of control parameters.

[0009] The method includes determining a first plurality of drilling rig operating points to be drilled, the operating points being set by a plurality of control parameters. Furthermore, percussion drilling is performed at each of the first plurality of operating points, and at least one final drilling parameter is evaluated for each of the plurality of operating points. The method also includes determining a new plurality of drilling rig operating points to be drilled based on the evaluation, and subsequently drilling at the new plurality of drilling rig operating points.

[0010] Regarding the terms "optimization" and "optimized," it should be understood that drilling optimization is finding a better operating point than the current drilling position. Therefore, the optimization according to the present invention is, from the perspective of final drilling parameters, such as drilling rate, finding a better operating point than the current operating point.

[0011] Regarding rock drilling, there are generally requirements for effective drilling, where efficiency is typically measured in productivity, and this productivity can be quantified by the drilling rate, i.e., the distance per unit time at the drilling location. However, while high productivity is desirable, it is also essential to ensure that drilling is carried out in a manner that does not unnecessarily subject the drilling rig to excessive wear that could lead to damage. Drilling rigs are typically operated manually, placing a significant responsibility on the operator regarding the drilling results. Inexperienced drillers may cause ineffective drilling, resulting in low output and excessive wear on the rig. On the other hand, experienced drillers can control drilling in a way that achieves high productivity while still protecting the rig from wear. Drilling rigs can also be automated, in which automatic operation will rely heavily on drilling using control parameter settings, which are initially derived from settings made by experienced drillers or those already considered to provide effective drilling based on experience.

[0012] Regarding productivity and wear, efficient drilling is generally achieved when a shock wave containing as much energy as possible is transmitted through the drill string to the rock being drilled, with not a large portion of the shock wave energy being reflected back to the drilling rig. Another important factor is that the typically threaded joints of the drill string are kept securely tightened, as further reflections would otherwise occur, degrading the drilling process. Loose joints also generate heat, which is both an energy loss and can potentially be harmful to drill string components.

[0013] According to the present invention, problems caused by suboptimal drilling can be mitigated by a system and method in which a first plurality of drilling machine operating points are determined, wherein the drilling machine is configured to continuously perform drilling at these operating points, and wherein the drilling machine is configured to operate at specific operating points by setting a plurality of control parameters for controlling the drilling. These control parameters may vary depending on the type of drilling technology used and may include at least two of the following for hydraulically driven drilling processes: an indication of impact pressure, an indication of feed pressure, an indication of drill string rotation speed, and an indication of flushing flow rate for flushing drilling residues from the hole being drilled. An indication of hydraulic flow may also be used in place of one or more of the aforementioned pressure indications, or as one or more of the aforementioned pressure indications.

[0014] When the drilling process is pneumatically driven or electrically driven, the corresponding control parameters are used to set the drilling machine to operate at a specific operating point.

[0015] According to the invention, drilling is performed at each of a plurality of determined operating points, and at least one final drilling parameter is evaluated for each of the plurality of operating points, i.e., the parameter is evaluated as a result of drilling. Then, based on this evaluation, a new plurality of operating points are determined, wherein the new plurality of operating points can be selected based on already drilled operating points considered to exhibit the best drilling results of the operating point being drilled, i.e., the best results with respect to the at least one obtained drilling parameter being evaluated. Then, the new plurality of drilling machine operating points are drilled, and new evaluations can be performed, based on which another new set of operating points can be determined based on the currently considered optimal operating points. The final drilling parameter on which the evaluation is based can be, for example, a drilling rate, wherein a higher drilling rate can be considered more ideal for drilling, but may also include other or additional drilling parameters as described below.

[0016] During drilling, operating points can be continuously determined and evaluated relative to at least one final drilling parameter for which evaluation is performed, and new groups of operating points can be continuously selected based on those currently considered optimal. When multiple operating points to be drilled are determined, the value of at least one control parameter can be increased and / or decreased.

[0017] Therefore, drilling can be continuously optimized, at least until no better operating point than the already evaluated operating point can be identified, at which point drilling can be set to operate. According to embodiments of the invention, optimization is continuously performed during drilling.

[0018] In this way, the drilling rig can be automatically configured to control drilling in a manner where the optimal operating point is identified substantially independently of the initial values ​​of the control parameters, because the optimization according to the invention strives to achieve increasingly ideal drilling, wherein the optimization is performed during drilling. This means that when the drilling rig is controlled, for example, by an inexperienced operator, the inexperienced operator may set the rig to drill with unfavorable settings; the control according to the invention can greatly mitigate the operator's lack of experience by optimizing the settings according to the invention. The invention is also useful in automated drilling, where automated drilling can be optimized, and even when drilling is controlled by an experienced operator, because according to the invention, evaluations can be continuously performed to further optimize the drilling.

[0019] According to an embodiment of the invention, each operating point can be drilled by the impact element of the drilling machine for a predetermined time period, such as intervals of 1 to 10 seconds, and / or a predetermined number of impacts, such as 50 to 300 impacts, before switching to a subsequent operating point to be drilled. In this way, drilling can be carried out for a sufficiently long time to allow for proper evaluation of the operating point, while drilling is not carried out for too long so that it would be more advantageous to drill at other operating points.

[0020] According to an embodiment of the invention, the method further includes evaluating multiple final drilling parameters for each of the multiple operating points being drilled, while evaluating the multiple operating points that have been drilled. As mentioned, drilling rate is generally an important factor and is usually maximized. However, as discussed above, situations that are harmful to the drilling rig and potentially harmful to the drilling rig may occur. This includes situations where impacts from the impact element cause loosening of the joint, and / or impacts occur when the drill string is pressed too tightly against the rock relative to the energy transmitted to the drill string by the impact element, and / or impacts occur when there is poor or no contact between the drill string and the rock. Therefore, according to an embodiment of the invention, when evaluating the operating point being drilled, other parameters, particularly those resulting from the current setting as control parameters, can be considered. Such final drilling parameters can also penalize the results, and thus such final drilling parameters can make operating points exhibiting high drilling rates less desirable than those exhibiting lower drilling rates, but also less penalized. Another example of a parameter to consider is the energy consumption of the drilling rig, where an operating point of a rig with the same drilling rate but lower energy consumption is generally better than an operating point with the same drilling rate but higher energy consumption.

[0021] According to embodiments of the invention, different weights and / or priorities are assigned to multiple drilling parameters during the evaluation. In this way, the most important drilling parameter, such as drilling rate, can be given a higher priority than, for example, energy consumption. Priorities can also be assigned to drilling parameters that may penalize the results, wherein, for example, operating points exhibiting, for example, high drilling rates, can be considered not to be used under conditions of high penalty.

[0022] According to an embodiment of the invention, the method further includes, when determining new plurality of drilling machine operating points: selecting new plurality of operating points starting from the drilling machine operating point considered the best operating point among the plurality of already drilled operating points. In this way, drilling can be continuously improved by finding increasingly better operating points, thereby driving drilling toward optimal convergence.

[0023] According to embodiments of the invention, optimization continues at least as soon as a better drilling machine operating point is identified. If drilling cannot be further optimized, drilling can be arranged to use an operating point already considered optimal.

[0024] According to an embodiment of the invention, once a point considered optimal has been found, other operating points in which control parameters vary to varying degrees can be selected. This can be performed to determine whether the already located optimal point is merely a local optimal or a more general optimal considering the constraints experienced by the drilling rig in terms of maximum and minimum values.

[0025] According to an embodiment of the invention, if an evaluation of a plurality of drilled operating points does not identify a better operating point than the one from which the drilled operating points were determined, at least one operating point from a plurality of other operating points to be drilled can be determined from the previously drilled operating points. According to an embodiment of the invention, in this case, the operating point can also be determined from previously drilled operating points from which no basis has yet been formed for determining a new set of operating points. For example, there may be operating points that have exhibited substantially the same results as operating points already used to determine other operating points to be drilled, and therefore can be used to generate new operating points to be drilled.

[0026] According to embodiments of the invention, the drilling machine operating point can be evaluated simultaneously with the drilling operation point, and it can be determined whether drilling at the evaluated operating point should be stopped before completing a predetermined number of impacts and / or drilling time periods. For example, it can be determined whether drilling at the operating point causes penalties such as harmful reflections and / or loose joints and / or drill bit jamming, as described above. In this case, drilling at the operating point can be stopped, and instead, drilling can be switched to a previously drilled operating point or a subsequent operating point to be drilled.

[0027] According to an embodiment of the invention, at least one obtained drilling parameter, such as a reflection or loosening joint, can be determined by measuring the reflected stress wave caused by the incident stress wave, which is produced by at least one impact impact on the drill string of the drilling rig by the impact device of the drilling machine.

[0028] Results regarding at least one drilling parameter can be arranged to estimate each stroke by an impact piston, wherein the length of the shock wave can be on the order of 200 μs and travels through the drill steel at, for example, a speed of 5000 m / s. Depending on the specific drilling rig used, the impact of the impact piston typically occurs at an impact frequency of 30 Hz to 120 Hz.

[0029] Sensors that can contact the drill string, or sensors that use sensors arranged close to the drill string, can be used to perform non-contact measurements of stress waves in the drill string. Such non-contact sensors can operate, for example, based on the principle of measuring changes in the magnetization of the drill string in response to stress waves traveling through it. Various suitable sensors or combinations of this type are known to those skilled in the art of rock drilling and therefore will not be discussed in detail here.

[0030] It is also conceivable that data such as shock wave and control parameter values, as well as final drilling parameters, could be collected during drilling, allowing harmful shock waves to be correlated with specific parameter values. This data could then be used to identify potentially harmful reflections without actually using shock wave sensors.

[0031] According to an embodiment of the present invention, the method further includes determining the control parameter settings to be used when drilling is to be performed at a specific operating point, and setting the drilling control parameters to the determined control parameter settings before drilling is performed at the specific operating point.

[0032] According to an embodiment of the invention, before generating new multiple operating points, it can be determined whether the difference in control parameter values ​​between operating points should increase or decrease. For example, if operating points among those that have just been drilled show similar results in evaluation, the difference in control parameter values ​​for subsequent multiple operating points can be increased to allow for faster detection of operating points that may be better than the current operating point. Conversely, if the obtained results vary significantly, and if drilling seems to be close to the optimal point, the difference can be decreased.

[0033] According to an embodiment of the invention, when drilling begins, the initial operating point from which to be drilled can be determined as an operating point previously used as the optimal operating point in the early drilling phase, an operating point determined empirically, or an operating point initiated by the operator. The initial operating point can also be, for example, selected as a previous operating point that has been found to be the optimal point for drilling another hole at a similar location and depth, which can be determined, for example, using any suitable positioning method of the drilling rig.

[0034] According to embodiments of the invention, the method further includes optimizing drilling by maximizing at least one drilling parameter, such as drilling rate, and / or minimizing at least one drilling parameter, such as power consumption, while maintaining a high drilling rate. Furthermore, impacts that cause harmful reflections can also be minimized.

[0035] According to an embodiment of the invention, the method further includes adhering to at least one maximum and / or minimum limit of a drilling parameter when determining subsequent multiple operating points to be drilled, in order to avoid damage to the drilling rig due to exceeding the limits and using operating points where the drilling rig is not designed to operate.

[0036] It will be understood that the embodiments described regarding the methodological aspects of the invention are also applicable to the system aspects of the invention. That is, the system can be configured to perform the methods defined in any of the embodiments described above. Furthermore, the method can be a computer-implemented method, for example, that can be implemented in one or more control units of a drilling rig.

[0037] Further features and advantages of the invention are indicated in the detailed description of the exemplary embodiments set forth below and in the accompanying drawings. Attached Figure Description

[0038] Figure 1 An exemplary drilling rig that can utilize embodiments of the present invention is illustrated;

[0039] Figure 2 The illustration shows a schematic schematic diagram of the optimized control according to an embodiment of the present invention;

[0040] Figure 3 An exemplary method according to an embodiment of the present invention is illustrated;

[0041] Figure 4 The illustration shows exemplary results during optimized drilling according to an embodiment of the present invention.

[0042] Figure 5 The diagram illustrates the following: Figure 4 The result of the optimization process. Detailed Implementation

[0043] Various embodiments of the invention will be illustrated below with reference to a particular type of drilling rig in which drilling is performed using an impact device in the form of a top hammer. The drilling rig can also be any other type, in which drilling is performed using a hydraulic impact device that transmits stress waves to the drill string to break the rock. The invention is also applicable to drilling rigs that include other types of impact drilling machines besides hydraulically driven drilling machines, such as drilling machines operated by electrical or pneumatic devices.

[0044] Figure 1 A rock drilling rig 100 according to an exemplary embodiment of the invention is illustrated, and an inventive method for optimizing at least one drilling parameter during an ongoing drilling process will be described with respect to the rock drilling rig 100. The drilling rig 100 is in the process of drilling a hole, wherein the current drilling has reached a depth x.

[0045] The rock drilling rig 100 according to this example constitutes an open-pit drilling rig, although it should be understood that the rig could also be a percussion rig primarily intended for, for example, underground drilling or for any other purpose. The rock drilling rig 100 includes a carrier 101 that conventionally carries a cantilever 102. Furthermore, a feed beam 103 is attached to the cantilever 102. The feed beam 103 carries a bracket 104 that is slidably arranged along the feed beam 103 to allow the bracket 104 to travel along the feed beam 103. The bracket 104, in turn, carries a percussion device (drilling machine) 105, and also includes, for example, a rotating unit (not shown, but rotation is indicated by 117), so that the percussion device 105 can travel along the feed beam 103 by sliding the bracket 104.

[0046] The impact device 105 is connected to the drilling tool, such as the drill bit 106 according to this example, via a drill string 107 in use. For practical reasons (except for potentially very short holes), the drill string 107 typically does not consist of a single drill string, but rather comprises multiple drill rods. When drilling has advanced a distance corresponding to the length of the drill rods, a new drill rod is threaded together with one or more drill rods that are already threaded together to form a drill string, thereby allowing drilling to advance another drill rod length before the new drill rod is threaded together with the existing drill rods. This is illustrated by drill rods 202 to 204, which are engaged together by threaded joints 206, 207. The drill bit 106 is engaged with drill rod 204 by means of threaded joint 208. Furthermore, the impact device 105 includes a drill shank (not shown), an impact element in the form of an impact piston 115 striking the drill shank, and the drill shank is connected to the drill rod 202 via threaded joint 205. Drill rods of the disclosed type can extend substantially to any desired length as drilling progresses.

[0047] In use, the impact piston 115 of the impact device 105 repeatedly impacts the drill shank and thus the drill rod to transfer shock wave energy to the drill string 107, and thus to the drill bit 106, and further to the rock to break it. In addition to providing rotation of the drill string and thus the drill bit 106 during drilling, the impact device 105 and / or the support 104 also provide a feed force acting on the drill string 107 by being subjected to forces acting in the drilling direction, thereby pressing the drill bit 106 against the rock surface being drilled.

[0048] According to the illustrated example, the impact device 105, particularly the impact piston 115, is powered by pressurized hydraulic fluid supplied to the impact device via a hydraulic pump 116 arranged on a carrier 101 and a suitable hose 118. The carrier 101 also includes a hydraulic fluid tank 119 from which hydraulic fluid is drawn and returned to power the impact device using a hydraulic circuit. Other hydraulic pumps may be present to provide pressurized hydraulic fluid in one or more additional hydraulic circuits, such as damping circuits.

[0049] According to the illustrated example, compressed air is guided to the drill bit 106 through a channel (not shown) inside the drill string 107, wherein the compressed air is supplied from the housing 109 to the drill string 107 in a manner known per se via a suitable connector 110 and hose 113 or other suitable means. The compressed air is generated by a compressor (not shown) that can inflate the housing 109, from which the compressed air is supplied to the drill string. The compressed air can be discharged through a hole in the drill bit 106 for cleaning the borehole to remove drill cuttings. The compressed air can alternatively be, for example, a mixture of compressed air and water or any other suitable type of mixture. Especially in open-pit drilling, the power consumption of the flushing system can be considerable and constitute a large portion of the total power consumption of the drilling rig. Therefore, according to embodiments of the invention, the applied flushing flow rate can be a control parameter that is desired to be optimized by minimization.

[0050] The hydraulic pump 116 and other power-consuming devices, such as the compressor, are driven by a power source 111, which is, for example, an internal combustion engine, such as a diesel engine, or any other suitable power source, such as an electric motor, or a combination of power sources. Figure 1The diagram also illustrates a sensor 209 for measuring stress waves induced in the drill string by the impact piston 115, as well as reflections occurring at different locations within the drill string and upon impact with the rock. As described above, sensor 209 can operate, for example, based on the principle of measuring changes in the magnetization of the drill string in response to stress waves traveling within it, wherein various such sensors are known in the art. For example, when performing estimations according to the invention, sensors illustrated in any of the documents EP 2811110 A1, EP 3266975 B1, WO 2007 / 082997A1, US 6,640,205 B2, US 7114576B2, and WO 2017 / 217905A1 can be used. The drilling rigs of the disclosed type also include, in a manner known per se, various pressure sensors for measuring, for example, the pressure in the supply path that provides pressurized hydraulic fluid to the impact piston 115 and the pressure of the supply mechanism that presses the drill string against the rock during drilling.

[0051] The rock drilling rig 100 also includes a drilling rig control system, which includes at least one control unit 120. The control unit 120 is configured to control various functions of the drilling rig 100, such as controlling the drilling process. When the drilling rig 100 is manually operated, the control unit 120 can receive control signals from an operator, for example, located in an operator's compartment 114, via operator-controllable devices, such as joysticks requesting various actions, and other devices, wherein the control signals, such as joystick deflections and / or manipulations of other devices caused by the operator, can be translated by the control system into appropriate control commands. The control unit 120 can, for example, be configured to request movements performed by various actuators, such as cylinders / motors / pumps, for example, to manipulate the boom 102, the feeder 103, and control the impact device 105, as well as various other functions. The described controls and other functions can alternatively be partially or fully autonomously controlled by the control unit 120.

[0052] The disclosed type of drilling rig may also include more than one control unit, such as multiple control units, wherein each control unit may be arranged to monitor and execute various functions of the drilling rig 100. However, for simplicity, it will be assumed below that the various functions are controlled by control unit 120. Such a control system may further utilize any suitable type of data bus to allow communication between the various units of the machine 100. When the drilling rig 100 is operated by an operator, various data may be displayed, for example, on one or more displays in the operator's compartment 114.

[0053] According to an embodiment of the present invention, a method for optimizing at least one drilling parameter is provided by a control unit of the drilling rig, such as... Figure 1The control unit 120 performs the optimization, but the optimization can also be configured to be performed in any suitable location.

[0054] As discussed above, the present invention relates to a method for optimizing the drilling process during drilling. Figure 2 The diagram illustrates the schematic principles of the invention, showing exemplary representations of parameters that can participate in optimization according to embodiments of the invention. Embodiments of the invention will now be described with reference to an example in which optimization is controlled to achieve the highest possible drilling rate while avoiding operating points that could lead to detrimental conditions over time. This is in... Figure 2 The diagram shows the drilling rate, which is the input drilling parameter to be maximized. The illustrated example also uses drilling control parameters in the form of impact pressure and feed pressure, which are varied to optimize the drilling rate.

[0055] There are also penalty drilling parameters input into the control. As explained, even if the drilling rate may be high, a particular operating point may still be undesirable. This involves, for example, loose joints, where indications of, for example, one or more loose joints can be used to determine that an operating point causing a high drilling rate may still be undesirable. This also involves impacts with poor rock contact or no rock contact, in which case a large portion of the initial impact energy will be reflected back to the drilling rig. Similarly, when the drill string is pressed too tightly against the rock, the impact energy may not be sufficient to break the rock and will therefore also be reflected back towards the drilling rig. Therefore, these parameters in Figure 2 The diagram illustrates a penalty parameter, where, for example, the number of occurrences or impacts by an impact element within a predetermined time period can serve as an indication that a specific operating point should not be used. (See also...) Figure 3 To further explain the control according to the invention, a basic search method is used to optimize drilling. However, this is merely an exemplary method, and any other suitable method, such as the simplex algorithm or any other optimization algorithm, can be used.

[0056] Furthermore, as shown in the following example, drilling is controlled using two control parameters: impact pressure and feed pressure. Figure 2 As indicated, other control parameters that also constitute the parameters to be minimized, such as rotational speed and flushing flow rate, can be used. As mentioned above, particularly regarding surface drilling, flushing flow rate can constitute a major component of the rig's total power consumption. Furthermore, if power consumption can be reduced while maintaining a high drilling rate, then for the same drilling rate, lower power consumption will naturally be considered better than higher power consumption. Regarding... Figure 2For example, optimization therefore aims to achieve the highest possible drilling rate, which is accomplished by controlling the impact pressure and feed pressure (and optionally the flushing flow rate and / or rotational pressure). These parameters are also typically subject to maximum and minimum limits that must be observed as described below.

[0057] The drilling machine is configured to drill at an operating point, which is determined by setting multiple control parameters. These control parameters may include, for example, rotational pressure, impact pressure, and feed pressure.

[0058] The following will refer to Figure 3 An exemplary method 300 according to an embodiment of the present invention is described. Method 300 is performed in an impact drilling machine, for example... Figure 1 The rock drilling rig shown optimizes at least one drilling parameter during the drilling process.

[0059] about Figure 3 An exemplary method is provided, which begins in step 301, in which it is determined whether drilling should be performed according to an automatic drilling optimization based on an embodiment of the invention. According to an embodiment of the invention, this can be arranged to be performed once drilling begins, i.e., regardless of whether drilling of a new hole has begun or whether drilling of a hole continues, for example, after adding drill pipe. The use of optimization can also be arranged to be selectable, for example, selectable by the drill operator, in case drilling is sometimes desired to be performed manually. However, it is considered that automatic optimization will be used essentially continuously while drilling is in progress.

[0060] When drilling optimization according to the invention is to be performed, the method continues to step 302, in which initial settings for optimization are determined in step 30. The initial settings may include, for example, setting control parameters (impact pressure and feed pressure according to this example) to initial values ​​that thus represent the initial operating point of the drilling.

[0061] The initial operating point can be, for example, one that has been found to be optimal for a previously drilled hole or for control parameters that have been previously determined to provide effective drilling. In the case of a recently drilled hole, it is advantageous to utilize the parameters that were found to be optimal during drilling. Alternatively, for example, previously drilled stored parameters can be utilized, where, for example, the type of rock can be input by the operator to select parameters previously considered to provide the desired results. The initial operating point can also be predetermined, for example, determined empirically, and stored during the manufacture of the drilling rig. According to embodiments of the invention, the initial settings can also be obtained according to settings made by the operator.

[0062] The method then proceeds to step 303, where a "box" is generated that defines a set of operating points to be drilled and evaluated relative to the initial operating point. The initial operating point is replaced by the current best operating point, which will change as optimization progresses, as described below.

[0063] When the operating points to be drilled are determined in step 303, these operating points are determined taking into account the differences in parameter values ​​relative to the initial operating points of specific controlled parameters, namely the impact pressure and feed pressure according to this example. That is, when a set of operating points to be drilled is determined for subsequent evaluation, the operating points will have different values ​​in terms of at least one of the control parameters used to control the drilling. The operating points to be drilled can be arranged to differ in terms of one or more of these drilling control parameters. According to this example, there are two control parameters and four operating points are defined, wherein each control parameter is allowed to increase and decrease relative to the initial operating point, thereby producing four operating points. According to embodiments of the invention, other operating points can be defined, and the parameter values ​​do not all need to increase and decrease relative to the initial value. In the case of using three control parameters, this can produce eight operating points if all possible combinations of increasing and decreasing values ​​are used. Similarly, four control parameters produce 16 operating points using this particular method. However, it should be noted that any number of operating points can be determined; that is, both higher and lower numbers can be used. The allowable variation limit for a specific control parameter value will be defined in a “box” in which a set of operating points are selected, where the allowable variation can be arranged to vary during optimization.

[0064] According to this example, since the operating point is determined by changing two control parameters, namely impact pressure and feed pressure, different impact pressures and / or different feed pressures are used in a set of operating points to be drilled, and according to the illustrated example, the box represents a two-dimensional area.

[0065] Other possible control parameters could be, for example, the rotational pressure or flushing flow rate as described above.

[0066] It should also be noted that the invention is illustrated herein with respect to a hydraulic drilling system in which, in particular, pressure is controlled. As discussed above, flow rate can be controlled alternatively, for example, and in the case of drilling using any other drilling technology, such as electric or pneumatic drilling, any other suitable control parameters can be controlled and changed in the same manner as discussed herein with respect to feed pressure and rotational pressure. It should also be noted that hydraulic flow rate can be used in place of one or more of the impact pressure, feed pressure, and rotational pressure.

[0067] Therefore, in step 303, the operating point to be drilled is determined by the spacing between the set drilling control parameters used for drilling. As will be explained below, this spacing or difference can be arranged to increase or decrease as drilling progresses. According to an embodiment of the invention, drilling can begin by utilizing large differences between parameter values, and then the most promising operating point among relatively widely spaced operating points is selected. The spacing between the individual operating points can then be gradually reduced, for example, to allow optimization with respect to the most promising operating point. Conversely, the spacing between control parameters can also be arranged to increase, for example, if substantially the same results are obtained for a set of drilled operating points. Gradients can also be determined. If, for example, optimization tends to proceed in a particular direction, the box can be selected to have points only in that direction, for example.

[0068] Furthermore, when the block is generated in step 303, maximum and minimum limits for drilling control parameters can be used to ensure that the machine is not configured to drill using parameters that deviate from, for example, maximum and minimum permissible values ​​from a structural perspective. These limits may include maximum and minimum impact pressure, maximum and minimum feed pressure, maximum and minimum rotational pressure, etc. These maximum and minimum values ​​may be predetermined, for example, to ensure that the component is not subjected to stresses and strains higher than the component is designed for. In addition to maximum and minimum limits for pressure, or as an alternative to maximum and minimum limits for pressure, these limits may also relate to other corresponding parameters, such as, for example, hydraulic flow rate. Furthermore, similar limits may typically be used for the specific drilling technique employed when drilling is not performed using a hydraulic drilling machine.

[0069] Once the operating point to be drilled has been determined, the method proceeds to step 304, where it is determined which operating point to drill. This selection can be performed, for example, by first selecting a lower value of the drilling control parameter, or first selecting a higher value of the drilling control parameter. The drilling order can also be random. Once the operating point to be drilled has been determined, drilling begins at that operating point in step 305.

[0070] In step 305, if the determination according to an embodiment of the invention is also performed in the drilling rig control system as appropriate, specific parameters for which drilling will be performed are first provided to the drilling rig control system (RCS) or the portion of the drilling control system that performs the actual drilling. When the drilling control parameters to be used have been provided to the drilling control system, a predetermined time period may be allowed to ensure that the desired parameter values ​​are set so that drilling is actually performed using the expected parameter values. Drilling may also be arranged to perform a predetermined number of impacts and / or a predetermined time period using the new control parameter values ​​to stabilize the drilling before collecting data for evaluation purposes, thereby obtaining representative measurement results.

[0071] The final drilling result resulting from the impacts of the impact piston using the drilling control parameters set according to this example is then monitored, and the drilling results for the specific settings are stored for later evaluation. This includes, for example, a representation of the drilling rate and other possible parameters involved in the evaluation. Drilling using a specific operating point can be arranged to perform a predetermined number of impacts (e.g., any suitable number of impacts in the range of 50 to 500) and / or a predetermined time period. During this period, drilling-related data is collected for later evaluation, and examples of specific data collected for evaluation are illustrated below.

[0072] When drilling at a specific operation point has been completed, the method returns to step 304, in which it is determined whether a different set of operation points has been completed, or whether there are other operation points to be drilled first.

[0073] As long as other operating points exist to be drilled, the method returns to step 305 for drilling according to the next setting. When all predetermined groups of operating points have been drilled and data has been collected for these different settings, the method continues to step 306 for evaluation according to the following.

[0074] However, further regarding step 305, for a specific operating point, it may not always be the case that drilling is performed for all impacts / for the entire time period. This is because a specific operating point being drilled may exhibit undesirable and potentially harmful results in some respects, even if, for example, the drilling rate may be high. As discussed, various penalty-generating parameters can be monitored during actual drilling at a specific operating point to determine whether drilling should be prematurely terminated to avoid excessive wear under specific settings. Penalty parameters can be any parameter or event considered to cause harmful drilling. See reference. Figure 2This can be the case if a joint is detected to be loose or potentially loose, or if drilling generates impacts while the drill string is firmly pressed against the rock relative to the impact pressure / energy. This causes stress wave energy to be reflected back towards the drilling rig. Similarly, when an impact piston strikes the drill string and thus generates an undesirable reflection, it can be determined whether the drill string has little or no contact with the rock. For example, it can also be determined whether drilling has caused the drill bit to become stuck, i.e., jammed, and whether the operating point is causing blockage, i.e., the flushing of drill cuttings is not being performed properly. This can be evaluated particularly when flushing flow rate is used as one of the drilling control parameters.

[0075] Therefore, while drilling is underway according to a specific setting, the drilling can be continuously evaluated, and if it is determined that the presence of a penalty-generating event is considered too high, for example, exceeding a threshold, drilling at the current operating point can be stopped before all expected impacts for the specific setting have been executed. For example, this could be the case if the number of impacts causing a penalty-generating event exceeds a predetermined threshold, in which case drilling at the current setting can be stopped before completing drilling at the specific setting.

[0076] Regarding the determination of whether harmful reflections have occurred, this can be performed in any suitable manner, and according to this example, it is done by analyzing the reflections caused by stress waves induced by the impact element. This is performed by measuring the reflected waves in the drill string using a non-contact sensor 209, wherein any suitable method can be used to estimate whether one or more joints are loose and whether the reflections reach a harmful level. This determination is well described in the art, and a method is illustrated in parallel application SE 2051XXX-X with the same assignee and application date as this application, in which, for example, loose joints can be identified by estimating the stiffness of the joints in the drill string, and wherein this can be performed for each stroke of the impact element. However, as mentioned, any other suitable method can be used to perform the determination according to the invention.

[0077] As mentioned, once all operating points have been drilled, the method proceeds to step 306, where the results of various settings are evaluated to determine which of the current drilling settings / operating points provides the best result with respect to at least one final drilling parameter. As you will appreciate, the term "best" is relative herein, and drilling is optimized when a new operating point is found that provides better drilling than previous operating points.

[0078] As discussed, the optimal operating point is determined using the final drilling rate according to this example. However, in order to achieve effective drilling over time, it is also important to ensure that drilling is not performed using control parameters that could lead to excessive wear on components. Therefore, the evaluation in step 306 may include identifying a specific operating point from a set of operating points that provides the highest drilling rate without violating penalty limits regarding loose joints, etc. Various parameters can therefore be involved in the evaluation in step 306, enabling the achievement of high drilling rates while taking into account the negative contributions of parameters that could cause excessive wear on the drilling rig.

[0079] Following the evaluation in step 306, in step 307, the optimal drilling setting from the recently drilled setup is selected. This optimal setting can also be transmitted to the drilling rig control system as the setting to be used if no other settings are received. The method then proceeds to step 308, where new prerequisites are determined. These new prerequisites will be used in step 303 when determining the next set of operating points to be drilled. This will include selecting the operating points that lead to optimal drilling, and may also include determining whether the differences in parameter values ​​between operating points should be increased or decreased. If different operating points recently drilled show similar results, the differences can be increased, further spacing the next set of operating points to be drilled; conversely, if results at different heights are obtained, the next set of parameters to be drilled can be arranged to be closer together. In step 309, it is determined whether the method should end in step 310, for example, due to the end of drilling; otherwise, in step 303, the prerequisites of step 308 are used to determine a new set of operating points to be drilled based on the above. Then, operating points are selected relative to those considered optimal in the evaluation of step 307, and these operating points can also be stored as new initial operating points for use in determining the operating points to be drilled at the start of the next optimization process according to the invention. As will be appreciated, these initial operating points can be changed many times during the drilling period.

[0080] Furthermore, when determining the operating point in step 303, according to embodiments of the invention, it can be ensured that it does not overlap with previously drilled operating points. It is also possible that no newly drilled operating point exhibits better drilling performance than the settings from which the operating point originated. Then, the new settings can be selected based on the last used "old" operating point and are therefore still considered optimal. The "box" can then be enlarged and / or arranged, for example, such that the value only increases (or decreases). It is also conceivable that the operating point in this case can be determined from previously drilled operating points, although these previously drilled operating points may not form the basis for determining a new set of operating points, but can still exhibit substantially the same efficiency (optimization) as the operating points for which further optimization has been attempted.

[0081] In this way, drilling can be continuously optimized during the drilling process, automatically performed by the drilling rig control system. This allows for efficient drilling not only when it is fully automated, but also when it is partially manually controlled, such that settings set by inexperienced drillers can be changed and optimized by the drilling rig control system during drilling. Consequently, drilling will also be efficient when the rig is in the hands of an inexperienced operator. This also allows drilling to continuously take into account, for example, changes in rock properties as drilling progresses.

[0082] Figure 4 Figure A illustrates an example of how control parameter settings, i.e., operating points, can be changed during drilling according to an embodiment of the present invention. As discussed, the number of controlled dimensions will depend on the number of control parameters involved in the optimization. According to this example, the drilling process is optimized in terms of impact pressure and feed pressure, thus generating a two-dimensional search space for optimizing the drilling settings, wherein, for example, according to Figure 3 In this method, point 401 represents the initial operating point from which optimization begins. Then, according to the above, the first set of operating points to be drilled is determined as points 401a to 401d. Operating point 401c is determined as the best operating point among the evaluated operating points 401a to 401d (and operating point 401), and is therefore used as the new operating point selected from among them. According to this example, one of the operating points coincides with point 401 and therefore does not need to be drilled. However, operating points 402b to 402d are drilled, and operating point 402d is considered better than operating point 401c, and therefore operating point 402d is used as a new "base" for determining the next operating point to be drilled.

[0083] The next set of operating points to be drilled includes points 403c and 403d, and also points that substantially coincide with points 401c and 401d, respectively. Operating point 403d is found to be optimal and is therefore selected. Similarly, operating point 404b is selected in a subsequent step. In this case, the box is also reduced, which can be done, for example, based on various criteria, such as relative improvements from one operating point to another. The method then continues in this manner, selecting points 405, 406, 407, 408, etc., thereby converging toward operating points representing the optimal operating point with respect to the drilling rate, given the specific prerequisites of the rock being drilled.

[0084] Figure 4 The diagram illustrates a solution in which optimization is performed in different directions and also in opposite directions within the search space shown in the attached figure, see, for example, 402d→403d and back to 404b. Alternatively, using gradients, assuming a start at point 401, the gradient can be determined, for example, at point 402d, and it may be advantageous to attempt further drilling along the lines intersecting points 401 and 402d.

[0085] Figure 5 The diagram serves as the basis. Figure 3 In terms of the evolution of the drilling rate (y-axis) as a function of the iteration (x-axis), Figure 4 The optimization process is as follows. As can be seen in the attached figure, the optimal operating point (relative to other operating points) was found after approximately 15 iterations. Specific values ​​for the drilling rate are given only as parameter values, which can be any suitable representation of the drilling rate.

[0086] This invention can be used with virtually any type of drilling rig employing hydraulic percussion drilling. Similarly, this invention is applicable to any other type of percussion drilling technology. This invention is also applicable to underground drilling rigs as well as drilling rigs operating on the surface.

Claims

1. A method for optimizing at least one drilling parameter during an ongoing drilling process, said drilling being performed by an impact drilling machine (105), said drilling machine (105) being configured to drill at an operating point, said operating point being determined by setting a plurality of control parameters, wherein, The method includes: The first plurality of drilling machine operating points (401a-401d; 402b-402d; 403c-403d; 404a-404d) are determined, wherein the operating points (401a-401d; 402b-402d; 403c-403d; 404a-404d) are set by the plurality of control parameters. Percussion drilling is performed at each of the first plurality of operating points (401a-401d; 402b-402d; 403c-403d; 404a-404d). Evaluate at least one final drilling parameter for each of the plurality of operating points (401a-401d; 402b-402d; 403c-403d; 404a-404d). Based on the assessment, several new drilling rig operating points (401a-401d; 402b-402d; 403c-403d; 404a-404d) are determined to be drilled, wherein the new operating points (401a-401d; 402b-402d; 403c-403d; 404a-404d) are derived from the previously drilled drilling rig operating points (401a-401d; 402b-402d; 403c-403d; 404a-404d). The drilling machine operating point (401; 401c; 402d; 403d; 404a-404d) is selected as the optimal operating point (401; 401c; 402d; 403d; 404b; 405-408) among the multiple drilling operating points (401a-401d; 402b-402d; 403c-403d; 404a-404d) that has been drilled. Drilling was performed at the aforementioned multiple new drilling machine operating points (401a-401d; 402b-402d; 403c-403d; 404a-404d), and At least one drilling parameter is determined by measuring the reflected stress wave caused by the incident stress wave, which is generated by at least one impact impact on the drill string of the drilling machine (105) by the impact device of the drilling machine (105).

2. The method according to claim 1, further comprising: During drilling, operations are based on the drilled points (401a-401d); 402b-402d; 403c-403d; The evaluation of 404a-404d continuously determines the operating points (401a-401d); 402b-402d; 403c-403d; 404a-404d), and Continuously drill and evaluate the identified operating points (401a-401d; 402b-402d; 403c-403d; 404a-404d).

3. The method according to claim 1 or 2, further comprising: When evaluating multiple operating points that have been drilled (401a-401d); 402b-402d; 403c-403d; When evaluating at least one drilling parameter for each drilled operating point (401a-401d) in the plurality of operating points (404a-404d), the parameters for the plurality of operating points (401a-401d) are evaluated. 402b-402d; Multiple drilling parameters for each operating point in 403c-403d; 404a-404d).

4. The method according to claim 3, further comprising: Different weights and / or priorities are assigned to the plurality of drilling parameters in the evaluation.

5. The method according to claim 1, further comprising: By determining at least as long as at the new plurality of operating points (401a-401d); 402b-402d; 403c-403d; The better drilling machine operating points (401; 401c; 402d; 403d; 404b; 405-408) identified in 404a-404d are the new operating points (401a-401d) that will be drilled. 402b-402d; 403c-403d; 404a-404d), continue to optimize the drilling machine operation points (401; 401c; 402d; 403d; 404b; 405-408).

6. The method according to claim 5, further comprising: When dealing with multiple drilling points (401a-401d); 402b-402d; 403c-403d; The assessment of 404a-404d did not identify the multiple operating points (401a-401d) from which the drilling was determined; 402b-402d; When the operating points (401; 401c; 402d; 403d; 404a; 404d) are considered to be better operating points (401; 401c; 402d; 403d; 404b; 405-408) than the previously drilled operating points (401; 401c; 402d; 403d; 404b; 405-408), additional operating points (401a-401d) are determined from the previously drilled operating points (401; 401c; 402d; 403d; 404b; 405-408). 402b-402d; 403c-403d; At least one of the operating points (404a-404d), wherein the previously drilled operating points did not form a new set of operating points (401a-401d); 402b-402d; The basis of 403c-403d; 404a-404d).

7. The method of claim 1, further comprising, before evaluating the drilling machine operating point: Perform impact drilling at the operation point to be evaluated for at least a predetermined number of impacts and / or for a predetermined time period.

8. The method according to claim 7, further comprising: The drilling machine operating point is evaluated while drilling is progressing to the aforementioned operating point. Determine whether to halt drilling at the assessed operating point, and When the assessment determines that drilling at the current operating point should be stopped, drilling will be switched to a previously drilled operating point or a subsequent operating point to be drilled before the predetermined number of impacts and / or drilling time period is completed.

9. The method of claim 1, further comprising, when drilling is performed at a specific operating point: Determine the control parameter settings to be used when drilling at the specific operating point; Set the drilling control parameters to the determined control parameter settings; and Drilling is performed at the specific operating point after the control parameters are set.

10. The method according to claim 1, further comprising: Based on the previously drilled operation point (401); 401c； 402d； 403d； 404b； 405-408) Determine multiple operating points to be drilled (401a-401d); 402b-402d; Before generating multiple new operation points (401a-401d; 402b-402d) (403c-403d; 404a-404d); Before operating at 403c-403d and 404a-404d, determine whether the difference in control parameter values ​​between the operating points (401a-401d, 402b-402d, 403c-403d, and 404a-404d) increases or decreases.

11. The method of claim 1, further comprising, at the start of drilling: The initial operating point (401) is selected from the operating point that was previously used as the optimal operating point in the early drilling phase, the operating point set by the operator of the drilling machine (105), or the operating point determined by experience (401a-401d; 402b-402d; 403c-403d; 404a-404d).

12. The method according to claim 1, further comprising: Drilling is optimized by maximizing at least one drilling parameter and / or minimizing at least one drilling parameter.

13. The method according to claim 1, wherein, The multiple control parameters include two or more of the following: rotational pressure, impact pressure, feed pressure, and flushing flow rate.

14. The method of claim 1, further comprising determining the plurality of operating points to be drilled (401; 401c; 402d; 403d; 404b; 405-408) from the optimal operating point (401; 401c; 402d; 403d; 404b; 405-408) of the plurality of operating points considered to have been drilled (401a-401d; 402b-402d; 403c-403d; 404a-404d): Select higher and / or lower values ​​for the control parameters associated with the drilling machine operating point (401; 401c; 402d; 403d; 404b; 405-408) that is considered the optimal operating point.

15. The method according to claim 13 or 14, further comprising: When the subsequent multiple operating points to be drilled (401a-401d) are determined; 402b-402d; 403c-403d; When drilling parameters 404a-404d are used, the maximum and / or minimum limits of at least one drilling parameter shall be observed.

16. A system for optimizing at least one drilling parameter during an ongoing drilling process, said drilling being performed by an impact drilling machine (105), wherein, During drilling, the drilling machine (105) is configured to drill at an operating point, the operating point being determined by setting multiple control parameters, characterized in that the system comprises: A device for determining multiple drilling machine operating points (401a-401d; 402b-402d; 403c-403d; 404a-404d), said operating points (401a-401d; 402b-402d; 403c-403d; 404a-404d) set by said multiple control parameters. A device for performing percussion drilling at each of the determined operating points (401a-401d; 402b-402d; 403c-403d; 404a-404d). A means for evaluating at least one final drilling parameter for each of the plurality of drilling rig operating points (401a-401d; 402b-402d; 403c-403d; 404a-404d). A means for determining new multiple drilling machine operating points (401a-401d; 402b-402d; 403c-403d; 404a-404d) to be drilled based on the assessment, wherein the new multiple operating points (401a-401d; 402b-402d; 403c-403d; 404a-404d) are derived from multiple drilling machine operating points (401a-401d; 402b-402d; 403c-403d; 404a-404d) already drilled. The drilling machine operating point (401; 401c; 402d; 403d; 404a-404d) is selected as the optimal operating point (401; 401c; 402d; 403d; 404b; 405-408) among the multiple drilling operating points (401a-401d; 402b-402d; 403c-403d; 404a-404d) that has been drilled. A device for drilling into the new plurality of drilling machine operating points (401a-401d; 402b-402d; 403c-403d; 404a-404d), and A device for determining at least one drilling parameter by measuring a reflected stress wave caused by an incident stress wave, the incident stress wave being generated by at least one impact-type impact of an impact device of the drilling machine (105) on the drill string of the drilling machine (105).

17. A rock drilling rig, characterized in that, The rock drilling rig includes the system according to claim 16.

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