A method of controlling a drilling apparatus

Abstract

A method for controlling a drilling apparatus (4), configured to perform a drilling operation in which said drilling apparatus breaks a mineral substrate (20). The drilling apparatus comprises a feed beam (6), a cradle (8), movable along the feed beam, and a drilling equipment (10). The drilling equipment comprises a hammer piston assembly (12), comprising a piston (13), wherein the hammer piston assembly is connected to the cradle, and a fluid supply system, configured to supply a fluid to said hammer piston assembly. The fluid supply system comprises an outlet, configured to release fluid from the fluid supply system during the drilling operation, and an evacuation valve, configured to release fluid from the fluid supply system when the evacuation valve is open. The method comprises controlling the drilling apparatus to perform the drilling operation, wherein the cradle moves towards the mineral substrate such that a feed force is applied towards said mineral substrate, and the fluid supply system moves the hammer in a series of reciprocating strokes. The method further comprises controlling the cradle to move away from the mineral substrate such that the drilling operation is interrupted. The method further comprises controlling the evacuation valve to open prior to moving the cradle away from the mineral substrate.

Description

[0001] A METHOD OF CONTROLLING A DRILLING APPARATUS

[0002] TECHNICAL FIELD

[0003] The present disclosure concerns a method for controlling a drilling apparatus. The invention also concerns a drilling apparatus and a drill rig. The disclosed method and drilling apparatus may for example be applied in rock drilling and down-the-hole drilling operations.

[0004] BACKGROUND

[0005] Where a drilling apparatus comprises a drilling equipment that uses a fluid driven hammer piston assembly, for example a down-the-hole drill, it may be advantageous to use the same fluid for both actuating the piston and for flushing of a formed hole. During a drilling operation the hammer piston assembly is moved towards a mineral substrate such that a feed force is applied to the mineral substrate, and a fluid is supplied to the hammer piston assembly such that the piston performs a series of reciprocating strokes. During the drilling operation fluid is also expelled from the drilling apparatus to perform the flushing function. However, when the hammer piston assembly is moved away from the mineral substrate, and the feed force is no longer applied towards the mineral substrate, the reciprocating strokes stop, and fluid is allowed to flow through the hammer without pressure buildup. Thus, pressure in the drilling apparatus is instantly released as the reciprocating motion stops. The instant release of pressure may in some cases damage components of the drilling apparatus, and / or lead to a collapsed collar.

[0006] SUMMARY

[0007] A primary objective of the present disclosure is to achieve an in at least some aspect improved drilling apparatus, drill rig and / or method for controlling a drilling apparatus. For example, it is an objective to achieve a method of controlling a drilling apparatus whereby a hammer piston assembly may be moved away from a mineral substrate subsequent to a drilling operation which at least partially alleviates the drawbacks associated with prior art methods, such as an instant release of pressure leading to, for example, air explosions. According to a first aspect of the disclosure, at least the primary object is achieved by a method according to claim 1. Hence, there is provided a method for controlling a drilling apparatus, configured to perform a drilling operation in which said drilling apparatus breaks a mineral substrate. Wherein the drilling apparatus comprises a feed beam, a cradle, movable along the feed beam, and a drilling equipment. The drilling equipment comprises a hammer piston assembly, comprising a piston, wherein the hammer piston assembly is connected to the cradle, and a fluid supply system, configured to supply a fluid, such as compressed air, to said hammer piston assembly. The fluid supply system comprises an outlet, configured to release fluid from the fluid supply system during the drilling operation, and an evacuation valve, configured to release fluid from the fluid supply system when the evacuation valve is open. The method comprises controlling the drilling apparatus to perform the drilling operation, wherein the cradle moves towards the mineral substrate such that a feed force is applied towards said mineral substrate, and the fluid supply system moves the piston in a series of reciprocating strokes. The method further comprises controlling the cradle to move away from the mineral substrate such that the drilling operation is interrupted. The method further comprises controlling the evacuation valve to open prior to moving the cradle away from the mineral substrate.

[0008] The feed force may be applied towards the mineral substrate via a drill bit, forming part of the drilling equipment, wherein the hammer strikes against the drill bit during the drilling operation. The mineral substrate may comprise a ground surface, or any type of surface, either defined by, for example, a geological formation, or aggregate, such as a layer of soil and / or rock fragments. The feed force may comprise a force sufficient for drilling of the substrate to occur. The drilling operation being interrupted may comprise moving the cradle such that a feed force is no longer applied towards the mineral substrate, or alternatively that the feed force applied is no longer sufficient for drilling of the substrate to occur.

[0009] The hammer piston assembly may further comprise a drill string, wherein the hammer piston assembly is connected to said cradle the via the drill string. The drill string may comprise one or more drill rods. The drill string may supply fluid and power to the drilling equipment via the drill rods. Furthermore, by attaching the hammer piston assembly to the cradle via a drill string, it may be possible to adapt the distance between the cradle and the hammer piston assembly, such that the drilling equipment can perform drilling operations at a greater range of depths. The hammer piston assembly is connected to the cradle such that the hammer piston assembly is movable with the cradle, such that when the cradle moves along the feed beam the hammer piston assembly similarly moves in the same direction along the feed beam. The hammer piston assembly may be mechanically connected to the cradle. The hammer piston assembly may be connected to the cradle via any number of components.

[0010] By providing a method for controlling a drilling apparatus whereby the evacuation valve is opened prior to moving the cradle away from the mineral substrate, i.e. , in a direction away from the mineral substrate, it is possible to release fluid, such as compressed air, from the fluid supply system such that a fluid pressure in the fluid supply system may be reduced. Furthermore, by reducing the fluid pressure in the fluid supply system, for example when the feed force is no longer applied towards the mineral substrate, a buildup of pressure in the fluid supply which leads to, for example, an air explosion, will be reduced, thereby reducing the magnitude of such an air explosion. This may reduce damages to the drilling apparatus and / or a likelihood of a collapsed collar.

[0011] Optionally, the method comprises measuring a pressure in the fluid supply system, wherein the action of controlling the cradle to move away from the mineral substrate is performed in response to determining that a measured pressure is less than a threshold pressure. The threshold pressure may correspond to a pressure value at which, for example, a movement of the cradle resulting in that the feed force is no longer applied towards the mineral substrate will lead to an air explosion having a reduced magnitude. The threshold pressure may be a predetermined constant pressure, alternatively the threshold pressure may be dependent on any number of variables, such as drilling depth, properties of the mineral substrate, properties of the drilling equipment, and may be determined before the drilling operation begins, or at any time during the drilling operation, or before the cradle is moved away from the mineral substrate. By performing the action of controlling the cradle to move away from the mineral substrate when a measured pressure is less than a threshold pressure it may be ensured that the pressure in the fluid supply system has been sufficiently reduced such that, for example, an air explosion will have a reduced magnitude.

[0012] Optionally, the action of controlling the cradle to move away from the mineral substrate is performed only after a predetermined time has elapsed after controlling the evacuation valve to open. The predetermined time may be a time sufficient for enough fluid to be released via the evacuation valve such that the pressure in the fluid supply system is reduced to a level whereby the magnitude of, for example, an air explosion is reduced. The predetermined time may be a constant, alternatively the predetermined time may be dependent on any number of variables, such as drilling depth, properties of the mineral substrate, properties of the drilling equipment, pressure in the fluid supply system, and it may be determined before the drilling operation begins, or at any time during the drilling operation. By performing the action of controlling the cradle to move away from the mineral substrate only after a predetermined time has elapsed after controlling the evacuation valve to open it may be ensured that the pressure in the fluid supply system has been sufficiently reduced such that for example, an air explosion will have a reduced magnitude.

[0013] Optionally, upon controlling the evacuation valve to open, the evacuation valve is kept at least partially open at least initially when controlling the cradle to move away from the mineral substrate. By keeping the evacuation valve at least partially open at least initially when controlling the cradle to move away from the mineral substrate as the pressure of the fluid supply system increases upon controlling the cradle to move away from the mineral substrate, at least some of the pressure may be relieved by the release of fluid through the evacuation valve such that, for example, an air explosion will have a reduced magnitude.

[0014] Optionally, the method comprises receiving a user request, wherein the action of controlling the evacuation valve to open is performed in response to receiving the user request. By controlling the evacuation valve to open in response to receiving the user request it is possible for a user to determine whether to perform the opening of the evacuation valve such that the evacuation valve can remain closed if a user deems it is unnecessary to open it, potentially saving time.

[0015] Optionally, the method comprises determining at least one parameter relating to the mineral substrate, wherein the action of controlling the evacuation valve to open is performed in response to the determined at least one parameter fulfilling a predefined condition. Determining at least one parameter relating to the mineral substrate may comprise performing at least one measurement, such as by measuring the parameter relating to the mineral substrate, or alternatively the measurement may be used to determine the at least one parameter relating to the mineral substrate.

[0016] Optionally, the at least one parameter relating to the mineral substrate is indicative of a ground condition. The ground condition may, e.g., relate to loose or overburden conditions, a composition of the mineral substrate, or an inclination of the mineral substrate.

[0017] Optionally, the at least one parameter relating to of the mineral substrate corresponds to a drilling depth. The drilling depth may correspond to a depth of the mineral substrate from the ground level, or alternatively the drilling depth may correspond to a depth of the mineral substrate relative to a starting position of the drilling operation. The predetermined condition may correspond to a range of depths, for example such that the depth is greater and / or less than a predetermined depth. For example, it may be advantageous to only control the evacuation valve to open at a depth where collaring has been established, such that the depth of the mineral substrate is greater than a threshold. Furthermore, it may be unnecessary to control the evacuation valve to open at depths which correspond to a more compact mineral substrate, for example at depths greater than an overburden layer, wherein the overburden layer comprises for example loose soil or rock fragments, such that the depth of the mineral substrate is less than a threshold.

[0018] According to a second aspect of the disclosure, at least the primary object is achieved by a drilling apparatus according to claim 9. Hence, there is provided a drilling apparatus, configured to perform a drilling operation in which the drilling apparatus breaks a mineral substrate. The drilling apparatus comprises a feed beam, a cradle, movable along the feed beam, and a drilling equipment. The drilling equipment comprises a hammer piston assembly, comprising a piston, wherein said hammer piston assembly is connected to the cradle, and a fluid supply system, configured to supply a fluid to the hammer piston assembly. The fluid supply system comprises an outlet, configured to release fluid from the fluid supply system during the drilling operation, and an evacuation valve, configured to release fluid from the fluid supply system when the evacuation valve is open. The drilling apparatus further comprises an electronic control unit configured to control the drilling apparatus to perform the drilling operation, wherein the cradle moves towards the mineral substrate such that a feed force is applied towards the mineral substrate, and the fluid supply system moves the piston in a series of reciprocating strokes. The electronic control unit is further configured to control the cradle to move away from the mineral substrate such that the drilling operation is interrupted. The electronic control unit is further configured to control the evacuation valve to open prior to moving the cradle away from said mineral substrate. The feed force may be applied towards the mineral substrate via a drill bit, forming part of the drilling equipment, wherein the piston strikes against the drill bit during the drilling operation.

[0019] By providing a drilling apparatus having an electronic control unit configured to control the evacuation valve to open prior to moving the cradle away from said mineral substrate it is possible to release fluid from the fluid supply system such that a fluid pressure in the fluid supply system may be reduced. Furthermore, by reducing the fluid pressure in the fluid supply system when the feed force is no longer applied towards the mineral substrate a build-up of pressure in the fluid supply system which leads to, for example, an air explosion, will be reduced, such the magnitude of for example, such an air explosion will be reduced, thus reducing damage to the drilling apparatus and / or a likelihood of a collapsed collar.

[0020] Optionally, the drilling apparatus comprises a drill string, wherein the hammer piston assembly is connected to said cradle the via the drill string. The drill string may comprise one or more drill rods. The drill string may supply fluid and power to the drilling equipment via the drill rods. Furthermore, by attaching the hammer piston assembly to the cradle via a drill string it may be possible to adapt the distance between the cradle and the hammer piston assembly, such that the drilling equipment can perform drilling operations at a greater range of depths.

[0021] Optionally, the drilling equipment comprises a compressor configured to pressurize the fluid in the fluid supply system. The fluid may preferably be air.

[0022] Optionally, the drilling apparatus comprises at least one pressure sensor configured to measure a pressure of the fluid in the fluid supply system, and the electronic control unit is configured to receive an input from the pressure sensor, the input being used by the electronic control unit to determine whether to control the cradle to move away from the mineral substrate. By using an input from the pressure sensor, the input being used by the electronic control unit to determine whether to control the cradle to move away from the mineral substrate, it may be ensured that the pressure in the fluid supply system has been sufficiently reduced such that, for example, an air explosion will have a reduced magnitude.

[0023] Optionally, the drilling apparatus comprises a user interface and the electronic control unit is configured to receive an input from the user interface, the input being used by the electronic control unit to determine whether to control the evacuation valve to open prior to moving the cradle away from the mineral substrate. The input may correspond to a user request, such that the evacuation valve may be controlled based upon the user’s intention. Alternatively, the input may correspond to at least one parameter, for example a parameter of the mineral substrate, or the drilling equipment, etc., wherein the at least one parameter may be used to determine how the evacuation valve is to be controlled. By using an input from the user interface, it may be possible for a user to assume at least some control in determining whether to open the evacuation valve, such that in at least some cases the operation of the drilling apparatus may be improved.

[0024] Optionally, the drilling apparatus comprises at least one sensor configured to measure a parameter relating to the mineral substrate and the electronic control unit is configured to receive an input from the at least one sensor, the input being used by the electronic control unit to determine whether to control the evacuation valve to open prior to moving the cradle away from the mineral substrate. The parameter may relate to a ground condition, a depth of the mineral substrate, etc.

[0025] Optionally, the fluid comprises air. Alternatively, the fluid may be supplied by a nitrogen source, a source of inert gas, or may comprise a mixture of gases.

[0026] According to a third aspect of the disclosure, at least the primary object is achieved by a drill rig comprising the drilling apparatus according to any one of claims 9-15.

[0027] BRIEF DESCRIPTION OF THE DRAWINGS

[0028] With reference to the appended drawings, below follows a more detailed description of embodiments of the disclosure cited as examples.

[0029] Fig. 1 is a schematic diagram of a drill rig according to an embodiment of the disclosure,

[0030] Fig. 2 is a schematic diagram of a drilling equipment according to an embodiment of the disclosure, Fig. 3 is a flow chart illustrating a method according to a first embodiment of the disclosure,

[0031] Fig. 4 is a flow chart illustrating a method according to a second embodiment of the disclosure.

[0032] Fig. 5 is a flow chart illustrating a method according to a third embodiment of the disclosure.

[0033] Fig. 6 is a flow chart illustrating a method according to a fourth embodiment of the disclosure.

[0034] The drawings show diagrammatic, exemplifying embodiments of the present disclosure and are thus not necessarily drawn to scale. It shall be understood that the embodiments shown and described are exemplifying and that the disclosure is not limited to these embodiments. It shall also be noted that some details in the drawings may be exaggerated in order to better describe and illustrate the disclosure. Like reference characters refer to like elements throughout the description, unless expressed otherwise.

[0035] DETAILED DESCRIPTION

[0036] Fig. 1 illustrates schematically a drill rig 2 comprising a drilling apparatus 4. The drilling apparatus 4 is configured to perform a drilling operation in which the drilling apparatus 4 breaks a mineral substrate 20. The drilling apparatus 4 may for example be configured for rock drilling and / or down-the-hole drilling operations. In the shown example the drill rig 2 comprises a mobile drill rig 2 comprising a carrier portion 28 having tracks for the movement thereof. In alternative examples the drill rig 2 may comprise wheels, or may be towable, to enable mobility thereof. Furthermore, in at least some examples the drill rig 2 may comprise a fixed structure. The drill rig 2 may comprise at least one power source (not shown) for powering the drilling apparatus 4, and any further equipment of the drill rig 2 such as tracks etc. The power source may comprise an engine, such as a diesel engine, or alternatively an electric motor, or any known power source. The drill rig 2 may be a manned drill rig 2 and may comprise a cabin wherein the drilling apparatus 4 and / or the movement of the drill rig 2 may be controlled, or alternatively the drill rig 2 may be a remote controlled, autonomous, or semi-autonomous drill rig. In the shown example the mineral substrate 20 comprises a ground surface extending substantially in a horizontal plane below the drill rig 2. In alternative embodiments the mineral substrate 20 comprises a surface extending at an angle with respect to a horizontal plane. Alternatively, the mineral substrate 20 may comprise a wall surface, or a roof surface such that the drilling equipment is operating in a substantially horizontal, or inverted configuration. As the mineral substrate 20 is drilled, a hole 26 is formed, wherein the mineral substrate 20 defines a drilled surface thereof. The depth of the hole 26 increases as the mineral substrate 20 is broken during a drilling operation. The hole 32 may have a circular cross-section.

[0037] The drilling apparatus 4 comprises a feed beam 6. In the shown example the feed beam 6 extends orthogonally to the mineral substrate 20. In alternative embodiments the feed beam 6 may extend at an inclination to an axis extending orthogonal to the mineral substrate 20. In the shown example the feed beam 6 is mounted to the carrier portion of the drill rig 2 via a boom 24. In alternative embodiments, for example wherein the drill rig 2 comprises a fixed structure, the boom 2 may be mounted to a portion of the drill rig 2 which is positionally fixed. Furthermore, in alternative embodiments the feed beam 6 may be attached directly to the carrier portion 28, a fixed structure, etc.

[0038] The boom 28 may be movable relative to, for example, the carrier 28, to which it is mounted, via any number of directions and / or around any axes, such that movement and / or rotation of the feed beam 6 may be achieved, relative to the carrier portion 28. Movement of the boom 28 may be achieved by hydraulic, pneumatic, electrically powered, or any known actuation means. The boom 28 may comprise any number of elements, wherein said elements may be movable relative to said carrier portion, and / or to one another, via any number of directions and / or around any axes, such that movement and / or rotation of the feed beam 6 may be achieved.

[0039] The drilling apparatus 4 comprises a cradle 8 movable along the feed beam 6 in a feed direction Y such that a feed force may be applied towards the mineral substrate 20. In the shown example, the feed direction Y is a direction orthogonal to the mineral substrate 20. The cradle 8 may be movable via a cradle actuation system (not shown), wherein the cradle actuation system may be hydraulic, pneumatic, electrically powered, or the like, and may comprise wheels, pulleys, pistons, etc. The cradle actuation system may comprise components integrated with and / or fixed to the feed beam 6 and / or the cradle 8. The movement of the cradle 8 along the feed beam 6 may also be achieved, at least partially, by gravity, where the feed beam 6 is oriented in a direction having a vertical component.

[0040] The drilling apparatus 4 comprises a drilling equipment 10, configured to perform a drilling operation. The drilling equipment 10 comprises a hammer piston assembly 12, connected to the cradle 8. The hammer piston assembly 12 may be mechanically connected to the cradle 8. The hammer piston assembly 12 may be connected to the cradle 8 via any number of components, for example the hammer piston assembly 12 may be clamped on the cradle 8 via a chuck or similar. By being connected to the cradle 8 the hammer piston assembly 12 is movable with the cradle 8 when the cradle 8 moves along the feed beam 6.

[0041] The hammer piston assembly 12 comprises a piston 13. By controlling a supply of fluid to the hammer piston assembly 12, during a drilling operation the piston 13 is movable in the feed direction Y, wherein the shown embodiment the feed direction Y comprises a direction orthogonal to the mineral substrate 20. The hammer piston assembly 12 may be used in conjunction with a drill bit 32. The drill bit 32 may be located between the piston 13 and the mineral substrate 20, whereby the feed force may be applied towards the mineral substrate 20 via the drill bit 32, and wherein the piston 13 strikes against the drill bit 32 during the drilling operation. In at least some examples, the piston 12 may additionally be rotated about an axis orthogonal to the mineral substrate 20 by rotation of the piston 12 by way of a rotation unit (not shown), whereby the piston 12 may be connected to the cradle 8 via the rotation unit.

[0042] The drilling apparatus 4 may further comprise a drill string 22, wherein the piston 12 may be connected to the cradle 8 via the drill string 22. The drill string 22 may be clamped on the cradle 8, such as by a chuck or similar. Where the drilling apparatus 4 comprises a rotation unit, the drill string 22 may be clamped by the rotation unit and in turn be connected to the hammer piston assembly 12. The hammer piston assembly 12 may be located at an end of the drill string 22. The drill string 22 may extend in the feed direction Y, wherein the shown embodiment the feed direction Y comprises a direction orthogonal to the mineral substrate 20. The drill string 22 may be configured to supply fluid and power to the drilling equipment 10. The drill string 22 may comprise at least one drill rod (not shown). In at least some embodiments the drill string 22 may comprise more than one drill rod, whereby and the length of the drill string 22 may be changed by the addition and / or removal of drill rods. Alternatively, where a single drill rod is used, the length of the drill string 22 may be changed by replacement of the drill rod with a different length drill rod. Additional drill rods may be stored on the drilling apparatus, for example in the shown embodiment the drilling apparatus 4 comprises a rod handling system 30.

[0043] Fig. 2 illustrates schematically the drilling equipment 10 according to the example of Fig 1. The drilling equipment 10 comprises a fluid supply system 14, configured to supply a fluid to the hammer piston assembly 12. By supplying fluid to the hammer piston assembly 12 during the drilling operation, the piston 13 may be actuated in a series of reciprocating strokes in the feed direction Y, between a top dead centre position and a bottom dead centre position, wherein drilling equipment 10 is configured to break the mineral substrate 20 by performing a series of impacts, wherein the impacts occur when the piston 13 moves towards the bottom dead centre position, such that, for example the drill bit 32 impacts the mineral substrate 20. Furthermore, the hammer piston assembly 12 may be rotated during the drilling operation.

[0044] The fluid supply system 14 further comprises an outlet 16, configured to release fluid from the fluid supply system 14 during the drilling operation. The fluid released from the fluid supply system 14 via the outlet 16 is used to provide flushing to the hole 26, whereby fragments formed during the breaking of the mineral substrate 20 are forced out of the hole 26. The outlet 16 may be formed at a drill bit 32 or at the end of the hammer piston assembly 12 which is closest to the mineral substrate 20 during a drilling operation. Alternatively, the outlet may be formed by a tube, or the like, fluidly connected to the hammer piston assembly 12, wherein said tube may be directed towards the mineral substrate 20.

[0045] The fluid supply system 14 further comprises an evacuation valve 18, configured to release fluid from the fluid supply system 14 when the evacuation valve 18 is open. The evacuation valve 18 may be configured such that it is positioned outside of the hole 26 during the drilling operation. In some examples the evacuation valve may be located on the drill rig 2, such as at the carrier portion 28 (Fig. 1). The evacuation valve 18 may be used in conjunction with a silencer (not shown), such that the noise produced during evacuation of fluid through the evacuation valve 18 may be reduced. The drilling equipment 10 further comprises a compressor 24 configured to pressurize the fluid in the fluid supply system 14. The fluid may comprise a gas such as air, nitrogen, inert gas, etc.

[0046] The drilling apparatus 4 may further comprise an electronic control unit (not shown) configured to control the drilling apparatus 4. The electronic control unit may be configured to control operation of the drilling apparatus 4 in response to an input received from a user interface (not shown), such as a user interface of a machine in which the drilling equipment 10 is provided, for example located at the carrier portion 28. The input from the user interface may be used by the electronic control unit to determine whether to control the evacuation valve 18 to open prior to prior to moving the cradle 8 away from the mineral substrate 20. In some examples the user interface may comprise an external device, for example a mobile computing unit. The user interface may comprise a touch screen, buttons, etc.

[0047] The electronic control unit may include a microprocessor, a microcontroller, a programmable digital signal processor or another programmable device. Thus, the electronic control unit comprises electronic circuits and connections (not shown) as well as processing circuitry (not shown) for communicating with different parts of the drilling equipment as well as with the user interface. For example, the electronic control unit may be configured for communicating with various sensors, devices, systems, and control units of the drilling apparatus. In the shown embodiment, the control unit may control the power source, the compressor 24, the evacuation valve 18, the cradle actuation system, and the boom actuation system. Alternatively, several separate control units may be provided.

[0048] The electronic control unit may comprise modules in either hardware or software, or partially in hardware or software, and communicate using known transmission buses such a CAN- bus and / or wireless communication capabilities. The processing circuitry may be a general- purpose processor or a specific processor. The control unit may comprise a non-transitory memory for storing computer program code and data. Thus, the skilled person realizes that the electronic control unit may be embodied by many different constructions.

[0049] The drilling apparatus 4 may comprise at least one pressure sensor (not shown) configured to provide the electronic control unit with a measurement indicative of a pressure of the fluid in the fluid supply system 14. In this case, the electronic control unit may be configured to receive an input from the pressure sensor and use it to determine whether to control the cradle 8 to move away from the mineral substrate 20.

[0050] The drilling apparatus 4 may comprise at least one sensor (not shown) configured to provide the electronic control unit with a measurement relating to the mineral substrate 20. The electronic control unit may be configured to receive an input from the at least one sensor and use the input to determine whether to control the evacuation valve 18 to open prior to moving the cradle 8 away from the mineral substrate 20.

[0051] The drilling apparatus 4 may comprise a communication system (not shown) configured to provide the electronic control unit with an input from an external source wherein the input may be used to determine the control of the drilling apparatus 4. The external source may comprise measuring equipment, other drilling apparatus, a personal computing device, or the like, or a server in communication with one of the aforementioned sources. The input may comprise measurements, for example relating to the mineral substrate 20, or instructions. The communication system may comprise a wired or a wireless communication system.

[0052] A method for controlling a drilling equipment 10 as described above is illustrated in Fig. 3. The method comprises the following actions:

[0053] S1: controlling the drilling apparatus 4 to perform the drilling operation, wherein the cradle 8 moves towards the mineral substrate 20 such that a feed force is applied towards the mineral substrate 20, and the fluid supply system 10 moves the piston 13 in a series of reciprocating strokes. The feed force may be applied towards the mineral substrate 20 via a drill bit 32, forming part of the drilling equipment 10, wherein the piston 13 strikes against the drill bit 32 during the drilling operation.

[0054] S2: controlling the cradle 8 to move away from the mineral substrate such that the drilling operation is interrupted.

[0055] S3: controlling the evacuation valve 18 to open prior to moving the cradle 8 away from the mineral substrate 20. The action S2 of controlling the cradle 8 to move away from the mineral substrate 20 may be achieved by moving the cradle 8 along the feed beam 6, by way of a cradle actuation system.

[0056] During the drilling operation the action S2 of controlling the cradle 8 to move away from the mineral substrate 20 may be performed only after a predetermined time has elapsed after the action S3 of controlling the evacuation valve 18 to open. The predetermined time may be a time sufficient for enough fluid to be released via the evacuation valve 18 such that the pressure in the fluid supply system 14 is reduced to a level whereby the magnitude of, for example, an air explosion is reduced. The predetermined time may be a constant, alternatively the predetermined time may be dependent on any number of variables, such as drilling depth, properties of the mineral substrate 20, properties of the drilling equipment 10, pressure in the fluid supply system 14, a user input, and may be determined before the drilling operation begins, or at any time during the drilling operation.

[0057] Upon the action S3 of controlling the evacuation valve 18 to open, the evacuation valve 18 may be kept at least partially open at least initially during the action S2 of controlling the cradle 8 to move away from the mineral substrate 20.

[0058] The drilling equipment 10 may be controlled such that the evacuation valve 18 opens prior to moving the cradle 8 away from the mineral substrate 20 each and every time the cradle 8 moves away from the mineral substrate 20. Alternatively, the evacuation valve 18 may open dependent on at least one further action. Some examples of further actions for the control of the opening of the evacuation valve will be described in further detail with reference to Figs. 5-6.

[0059] The method for controlling the drilling equipment 4 as described above may further include the additional step illustrated in Fig. 4. The additional step comprises the following action:

[0060] S4: determining that a measured pressure is less than a threshold pressure.

[0061] In this case, the action S2 of controlling the cradle 8 to move away from the mineral substrate 20 may be performed in response to determining in the action S4 that the measured pressure is less than a threshold pressure. The threshold pressure may correspond to a pressure value at which, for example, a movement of the cradle 8 such that the feed force is no longer applied towards the mineral substrate 20 will lead to an air explosion having a reduced magnitude. The threshold pressure may be constant, alternatively the threshold pressure may be dependent on any number of variables, such as drilling depth, properties of the mineral substrate, properties of the drilling equipment, and may be determined before the drilling operation begins, or at any time during the drilling operation, or before the cradle 8 is moved away from the mineral substrate 20.

[0062] In order to determine that the measured pressure is less than the threshold pressure, a pressure in the fluid supply system 14 must be determined. This may be achieved by measuring the pressure of the fluid in the fluid supply system 14 using a pressure sensor located in the fluid supply system 14. Alternatively, other measurements could be used, for example a temperature and / or a flow rate of the fluid may be measured, such that a pressure of the fluid may be calculated therefrom.

[0063] The method for controlling the drilling equipment 4 as described above may further include the following additional action illustrated in Fig. 5:

[0064] S5: receiving a user request.

[0065] In this case, the action S3 of controlling the evacuation valve 18 to open may be performed in response to receiving the user request. The user request may comprise an input performed by a user via a user interface. The user request may comprise an input indicating that the evacuation valve 18 should be controlled such that it opens prior to controlling the cradle 8 to move away from the mineral substrate 20. In alternative examples the user request may comprise an input indicating that the cradle 8 may move away from the mineral substrate 20 whilst controlling the evacuation valve 18 to be maintained at a closed position. In some examples the user may make either a request to control the evacuation valve 18 to either open, or to maintain a closed position prior to controlling the cradle 8 to move away from the mineral substrate 20. The user request may be performed before the drilling operation, at any time during the drilling operation, or after the drilling operation, for example the action S2 of controlling the cradle 8 to move away from the mineral substrate 20 may be delayed after the end of a drilling operation such that a user has sufficient time to make a user request, alternatively the delay may be for an indefinite amount of time until a user request is performed. As further illustrated in Fig. 6, the method for controlling the drilling equipment 4 as described above may further include the following action:

[0066] S6: determining at least one parameter relating to the mineral substrate 20, e.g., by measuring the at least one parameter.

[0067] In this case, the action of controlling S3 the evacuation valve 18 to open may be performed in response to the determined at least one parameter fulfilling a predefined condition. The at least one parameter relating to the mineral substrate 20 may be indicative of a ground condition, such as loose or overburden conditions. Such conditions may be detected by measuring a void ratio, wherein the at least one parameter may comprise the void ratio. The predefined condition may be defined such that it is considered fulfilled when the void ratio is greater than a threshold. Alternatively, the ground condition may correspond to a composition of the mineral substrate whereby the predefined condition may be defined such that it is fulfilled when the composition is a particular composition or a particular set of compositions. The ground condition may also correspond to an inclination of the mineral substrate, whereby the predefined condition may be considered fulfilled when the inclination is greater than a threshold. The sensor used to measure the ground condition may be configured to take measurements during the drilling operation, for example a rate of penetration, thrust force, or torques from which properties of the mineral substrate 20 may be determined as the mineral substrate 20 is drilled. Alternatively, the sensors used may relate to cameras, ground-penetrating radar, X-Ray, electric tomography, reflection seismology, or magnetotelluric imaging methods and the like, whereby such sensors may comprise part of the drilling apparatus 4, or alternatively may comprise an external sensor communicable with the drilling apparatus 4.

[0068] The at least one parameter relating to the mineral substrate 20 may correspond to a depth of the mineral substrate. The predetermined condition may correspond to a range of depths, for example such that the depth is greater and / or less than a predetermined depth. For example, it may be advantageous to only control the evacuation valve 18 to open at a depth where collaring has been established, such that the depth of the mineral substrate 20 is greater than a threshold. Furthermore, it may be unnecessary to control the evacuation valve 18 to open at depths which correspond to a more compact mineral substrate 20, for example at depths greater than an overburden layer, wherein the overburden layer comprises for example loose soil or rock fragments, such that the depth of the mineral substrate 20 is less than a threshold. The depth of the mineral substrate 20 may be determined from the drilling apparatus 4 using any known method, for example using the length of the drill rod 22, and by tracking the movement of a cradle actuation system and / or a boom actuation system, or by use of visual indicators which may be applied to the drill rod and observed from the surface by a camera, user, etc. Alternatively, the depth of the mineral substrate may be determined using a laser and an associated sensor, whereby such sensors may comprise part of the drilling apparatus 4, or alternatively may comprise an external sensor communicable with the drilling apparatus 4.

[0069] It is to be understood that the present disclosure is not limited to the embodiments described above and illustrated in the drawings; rather, the skilled person will recognize that many changes and modifications may be made within the scope of the appended claims.

Claims

CLAIMS1. A method for controlling a drilling apparatus (4), configured to perform a drilling operation in which said drilling apparatus (4) breaks a mineral substrate (20), wherein said drilling apparatus (4) comprises: a feed beam (6), a cradle (8), movable along said feed beam (6), a drilling equipment (10), the drilling equipment (10) comprising: a hammer piston assembly (12), comprising a piston (13), wherein said hammer piston assembly (12) is connected to said cradle (8), a fluid supply system (14), configured to supply a fluid to said hammer piston assembly (12), wherein the fluid supply system (14) comprises: an outlet (16), configured to release fluid from said fluid supply system (14) during the drilling operation, an evacuation valve (18), configured to release fluid from said fluid supply system (14) when said evacuation valve (18) is open, wherein the method comprises: controlling (S1) the drilling apparatus (4) to perform the drilling operation, wherein said cradle (8) moves towards the mineral substrate (20) such that a feed force is applied towards said mineral substrate (20), and said fluid supply system (10) moves said piston (13) in a series of reciprocating strokes, controlling (S2) the cradle (8) to move away from said mineral substrate such that the drilling operation is interrupted, wherein the method further comprises controlling (S3) the evacuation valve (18) to open prior to moving the cradle (8) away from said mineral substrate (20).

2. The method for controlling the drilling apparatus (4) according to claim 1 , wherein the method comprises: measuring a pressure in said fluid supply system (14), wherein the action of controlling (S2) the cradle (8) to move away from said mineral substrate (20) is performed in response to determining that a measured pressure is less than a threshold pressure.

3. The method for controlling the drilling apparatus (4) according to any one of the preceding claims, wherein the action of controlling (S2) the cradle (8) to move away from said mineral substrate (20) is performed only after a predetermined time has elapsed after controlling (S3) the evacuation valve (18) to open.

4. The method for controlling the drilling apparatus (4) according to any one of the preceding claims, wherein upon controlling (S3) the evacuation valve (18) to open, said evacuation valve (18) is kept at least partially open at least initially when controlling (S2) the cradle (8) to move away from said mineral substrate (20).

5. The method for controlling the drilling apparatus (4) according to any one of the preceding claims, wherein the method comprises: receiving a user request, wherein the action of controlling (S3) said evacuation valve (18) to open is performed in response to receiving said user request.

6. The method for controlling the drilling apparatus (4) according to any one of claims 1-4, wherein the method comprises: determining at least one parameter relating to the mineral substrate (20), wherein the action of controlling (S3) said evacuation valve (18) to open is performed in response to the determined at least one parameter fulfilling a predefined condition.

7. The method for controlling the drilling apparatus (4) according to claim 6, wherein the at least one parameter relating to the mineral substrate (20) is indicative of a ground condition.

8. The method for controlling the drilling apparatus (4) according to claim 6 or 7, wherein the at least one parameter relating to the mineral substrate (20) corresponds to a drilling depth.

9. A drilling apparatus (4), configured to perform a drilling operation in which said drilling apparatus (4) breaks a mineral substrate (20), the drilling apparatus (4) comprising: a feed beam (6), a cradle (8), movable along said feed beam (6),a drilling equipment (10), wherein the drilling equipment (10) comprises: a hammer piston assembly (12), comprising a piston (13), wherein said hammer piston assembly (12) is connected to said cradle (8), a fluid supply system (14), configured to supply a fluid to said hammer piston assembly (12), wherein the fluid supply system (14) comprises: an outlet (16), configured to release fluid from said fluid supply system (14) during the drilling operation, an evacuation valve (18), configured to release fluid from said fluid supply system (14) when said evacuation valve (18) is open, wherein the drilling apparatus (4) further comprises an electronic control unit configured to: control the drilling apparatus (4) to perform the drilling operation, wherein said cradle (8) moves towards the mineral substrate (20) such that a feed force is applied towards said mineral substrate (20), and said fluid supply system (14) moves said piston (13) in a series of reciprocating strokes, control the cradle (8) to move away from said mineral substrate (20) such that the drilling operation is interrupted, and control the evacuation valve (18) to open prior to moving the cradle (8) away from said mineral substrate (20).

10. The drilling apparatus (4) according to claim 9, wherein the drilling apparatus (4) comprises a drill string (22), and wherein said hammer piston assembly (12) is connected to said cradle (8) via said drill string (22).

11. The drilling apparatus (4) according to any one of claims 9-10, wherein the drilling equipment (10) comprises a compressor (24) configured to pressurize the fluid in said fluid supply system (14).

12. The drilling apparatus (4) according to any one of claims 9-11, wherein the drilling apparatus (4) comprises at least one pressure sensor configured to measure a pressure of the fluid in said fluid supply system (14), and the electronic control unit is configured to receive an input from said pressure sensor, said input being used by theelectronic control unit to determine whether to control the cradle (8) to move away from said mineral substrate (20).

13. The drilling apparatus (4) according to any one of claims 9-12, wherein the drilling apparatus (4) comprises a user interface and the electronic control unit is configured to receive an input from said user interface, said input being used by the electronic control unit to determine whether to control said evacuation valve (18) to open prior to prior to moving the cradle (8) away from said mineral substrate (20).

14. The drilling apparatus (4) according to any one of claims 9-12, wherein the drilling apparatus (4) comprises at least one sensor configured to measure a parameter relating to the mineral substrate (20) and the electronic control unit is configured to receive an input from said at least one sensor, said input being used by the electronic control unit to determine whether to control said evacuation valve (18) to open prior to moving the cradle (8) away from said mineral substrate (20).

15. The drilling apparatus (4) according to any one of claims 9-14, wherein the fluid comprises air.

16. A drill rig (2) comprising the drilling apparatus (4) according to any one of claims 9-15.

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