Patent Application
20250207470
The present invention relates to a drilling equipment variable diameter guide bushing device for changing mining drilling tools in a drill string.
Mobile drilling units (or drilling rigs) are responsible for drilling blast holes in mining, quarrying and prospecting operations. These surface units have a pivoting mast mounted on a drilling platform; A drill string is mounted inside or in front of the mast and rotated to drill into the ground. The drill string consists of, depending on the technique used, a drilling tool (bits or tricone), a series of bars and some intermediate devices, the drill bit is mounted on the lower working end of the drill string, the sections or bars connect the drilling tool to a mast-mounted rotation source.
The drill injects a liquid or gaseous fluid to extract the debris resulting from the operation. This fluid and the torque are transmitted through the bars to the drill or tricone tool to allow the drilling maneuver; As the drilling job progresses, more bars are added to the string depending on the depth and reach needs of the drilling operation.
The drills operate by means of bars that rotate on their axis and depending on the type of technology, they can only rotate on the ground or they can additionally incorporate percussion during rotation; Based on the above, there are basically 3 technologies, the first of them is known as tricones and works only by rotation and pressure, removing the debris using compressed air. They are used for production (installation of explosives) and their main applications are for diameters greater. The second technology is known as DTH (Down the hole) which works by rotation and percussion; The generation of percussion is in the head of the drill and normally removes the debris using water. The third technology is known as Top Hammer, the principle of which is based on rotation and percussion, but, unlike DTH technology, the percussion is generated in a percussion hammer that is at the end of the bar just before the drill bit; The activation of the hammer, as well as the removal of debris, is carried out by means of compressed air.
At the end of the drilling string (column of the bars and tools) is the drill bit that is in contact with the rock and allows drilling in the rocks thanks to the energy being transmitted through the bars; the drill bits bearing inserts of high hardness materials such as tungsten carbide, industrial diamonds, etc. These inserts are abraded by abrasion by being in permanent contact with the rock so that it is necessary to change them with different frequency depending on the type of rock material being drilled.
Surface drilling rigs have a mast that has a head that has the ability to raise and lower the rod according to the position required depending on whether it is in the drilling process and its depth. The head additionally has a hydraulic motor that is coupled to the bar and that allows it to rotate. The length of the drill rods depends on the designs and configuration of the mine, but they are usually between 6 and 8 meters.
The mast has the height sufficient to support up to two drill rods in addition to the hammer so that the distance between the rod intake and the drill mouth can reach 18 meters. During the drilling process, the bar has the tendency to sag or bend product from rotation and pressure exerted thereon from the head. In order to control this bending phenomenon, which is quite inconvenient, it is positioned on the rig platform a steel bushing that works in conjunction with the bar to prevent bending of the bar from occurring.
The drilling bit has a diameter larger than that of the bar and at the same time has a diameter that is larger than the diameter of the guide bushing on the platform, which means that the drilling bit cannot be passed through the bushing once. Once the drill string tube has passed, due to this, each time the drill bits are changed, it is necessary to remove the guide bushing from the surface by lifting it through the bar. This task is normally carried out by the operator manually, resulting in several inconveniences. This work, firstly the weight of the bushing varies depending on the diameter of the bar but can reach weights of over 40 kilos and the number of changes per day varies depending on the mining operation but may be from a change every several days to operations in which 8 changes per day are reached.
The mining trend is to avoid the presence of operators in drilling work, which is why it is aimed at automation or remote operation of the equipment. The existence of this guide bushing forces the operator to be present during the drill bit changing process, placing him in a situation of risk and danger, while said operation generates losses due to the downtime of the equipment while the bushing is removed. of the platform and the respective change of bit.
In the state of the art, some equipment and devices are known that allow guiding drilling pipes and strings, but in other fields such as hydrocarbons and for other purposes such as that shown in patent PT218346, a guide is revealed in this document. adjustable to position a portion of a pipe string within a pipe gripper assembly, such as a riser or spider assembly. Relates to an adjustable guide for directing a pipe end at the bottom of a riser assembly being lowered by a winch onto a drilling rig, or for centering a pipe connection so that it can pass through a spider on a drilling platform.
Wells are drilled into the Earth's crust and completed to establish a fluid conduit between the surface and a specific geological feature, such as a formation containing oil or gas. Tubing strings used to drill or complete a well can be made as they pass into a drilled well. A casing string may be cemented in a specific interval of a drilled well to prevent wellbore collapse and/or the formation of fluid crossflow, and to isolate the interior of the well from corrosive geologic fluids.
A string of tubing can be suspended in a well from a drilling rig using a tubing grab assembly, for example, a spider, and lengthened step by step by threading a segment of tubing into the hole. proximal end of the tubing string on the drilling rig. The elongated pipe string can then be suspended using a second type of gripper assembly, for example, a riser assembly that can be movably supported from a winch and tower above the spider.
As the loading of the pipe string is transferred from the spider to the winch and the tower, the spider can be discharged and then disengaged from the pipe string by retracting the spider wedges. The elongated pipe string can then be further shortened in the well using the winch. The spider can again engage and support the tubing string within the wellbore and may attach an additional pipe segment to the new proximal end of the pipe string to further lengthen the tubing string.
In addition to the fact that similar solutions are not known in the mining field to solve the problem described, it is also important to indicate that the cost of lost profits due to having the equipment without drilling is very high, both due to the value of the equipment and all the assistance it requires as well as which is no longer produced, which is why it is of great interest to find ways to replace the drill bits that are automated and that do not generate a problem of stopping the equipment to change the guide bushing that is on the drilling platform; In the same way, it is very important to avoid the danger of exposure of the operators of the equipment and which, in addition, dramatically reduces the turnover time for the equipment to return to the drilling tasks and the lowest least possible time is lost in stopping said equipment.
Therefore, there is a clear need for providing room equipment or devices and associated methods for making the change of drill bits in the drill strings through automatic operations where exposure of human operators to this hazardous operation is avoided and the stopping time of the equipment is achieved.
More particularly, the present invention is related to a device used in mining to change the bits or tricones of the drilling strings that replaces the traditional guide bushing that is commonly found in the drilling deck. The variable diameter guide bushing device can do all the tasks necessary to change drill bits without physical intervention of people.
Going now into detail of the construction configuration of the variable diameter guide bushing device of the present invention and considering the figures presented, a device for replacing the drilling tools is provided that allows the change of the drilling bit on the platform automatically.
The variable diameter guide bushing device for changing the drill bits or tricones of the drilling strings has an upper surface that has an outer segment and an inner segment that has a diameter which is variable or that can be sealed at will., the device has a central body that houses a structure of drum or roller elements (1) inside and a lower surface that has a lower surface that has an outer segment and an inner segment that has a diameter which is variable to willpower.
In operation of the drilling work the string passes through the device below the drilling platform replacing the guide bushing that is usually on top of the platform, in such a way that the upper surface device is configured to receive the drill string and in the mode The drill bit has the diameter that corresponds to said string and in the drill bit change mode it is capable of changing its diameter at will to a diameter greater than that of the drill bit so that said drill bit is capable of changing to across the entire device.
Going into more detail about the configuration of the variable diameter guide bushing to change the drill bits or tricones of the drilling strings, said equipment is configured or provides an upper surface that has an outer segment and an inner segment that It has a diameter which is variable or can be blocked at will; In said outer segment there is an upper covering ring element (14); In said interior segment there is an upper covering element (21) that retains water from entering the device, the purpose of the upper ring element (14) is to fix the upper covering (21).
On the upper surface there is also a set of nozzle elements (16) into which a cleaning fluid can be injected, there is also a set of fixing bolts (17, 18, 19, 20, 33) that fix the upper surface with a lower surface of the device which will be discussed later. On this upper surface there is also a support and fixing element (4) to the drilling machine.
The variable diameter guide bushing for changing the drill bits or tricones of the drilling strings additionally has a central body that inside houses a structure of drum or roller elements (1) which is in contact with the bar. drilling machine, these roller elements have a set of bearing elements (37) with a set of axis elements (27) that are arranged through the bearing elements (37) for the rotation of said drums; The drums (1) also have additional elements such as a rotating arm element (3) which is disposed at the bottom of the drum and an arm shaft element (26) which is attached to the swing arm member (3) to allow rotation of the drums; The drums (1) also have a set of cover elements (32) and seals (29), insurance elements (36) and sealing rings (35) that restrict contamination inside the roller elements (1).
It is obvious from the figures presented that the drum sets can be replicated, in the modalities shown they are replicated up to six times in the structure of the guide bushing as well as the structures that compose them, that is, their bearings, shaft, arm shaft, swing arm, covers, seals, insurance elements and sealing rings. It is understood that there may be variations of the drum or roller elements (1) in such a way that the bar containment system may be through this system or other rock elements.
The central body of the device also has a lower and upper cam assembly (2, 28) with pin elements (11) and ring elements (15) which guide the movement of the drum structure or rollers (1); also present in this central body of the device a set of top and bottom caps (5, 31) holding the cam assembly (2, 28); a cylinder element (6, 7) arranged with a base (10), a trigger element (8) and spacer elements (22, 23) that exerts rotational torque to move the cam assembly (2, 28); a set of locking elements (9) for preventing axial movement of the central body; a adjuster element (25) is also provided that determines and adjusts the distance between the upper and lower covers or covers (5, 31); said central body also has an arm shaft element (26) wherein the roller arm is rotated having a vertical separator element (30) to maintain the height of the roller arm; in the central body also a cavity or lubrication element (34) is provided for introducing lubrication fluids to the device.
The device for changing the drill bits or tricones of the drilling strings additionally has a lower surface that has an outer segment and an inner segment that has a diameter which is variable at will. On said lower surface in the outer segment there is a lower covering ring covering element (13) and in the inner segment there is a lower covering element (12) that retains the entry of water into the device in addition to the ring element. The purpose of the upper covering ring (13) is to fix the lower covering (12), on the lower surface there is also a set of fixing bolts (17, 18, 19, 20, 33) that fix said lower surface with the top surface of the device.
The device for changing the drill bits or tricones of the drilling strings is configured to receive the drilling string and in the drilling mode said surfaces have the diameter that corresponds to the string and in the drilling bit changing mode. Drilling surfaces are capable of changing their diameter at will to a diameter larger than that of the drilling bit so that the drill bit is able to pass through the entire device.
The structure of drum or roller elements (1) of the central body is integral and configures an initial diameter that is equal to that of the drilling string when drilling tasks are carried out and a final or change diameter that is at least greater than diameter of the drilling bit so that said bit can pass through the drum or roller elements (1).
In another embodiment of the invention and according to
While the present invention has been described with the preferred embodiments shown, it is understood that modifications and variations that retain the spirit and scope of this invention are understood within the scope of the appended claims.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IB2021/058873 | 9/28/2021 | WO |
