TECHNICAL FIELD
The present invention relates in general to drill rigs, and more particularly to an adjustable breakout wrench for blasthole drill rods of different diameters.
BACKGROUND OF THE INVENTION
It is common in the mining industry, and in particular in the field of drill rigs used for blasthole drilling through hard rock, that the connections between sections of the drill string and the drill rod become fixed together by the normal operational loads of the drill rig. This creates sections that are difficult to loose without the use of a breakout wrench to apply high torques to the drill strings in order to loose the fixed connections. These breakout wrenches are traditionally only useful for disengaging a drill string of a definite diameter. In cases in which different diameters of drill strings need to be loosed, different wrenches need to be used for each of them, resulting in an ineffective process of replacing the breakout wrench of the blasthole drill, each time that a drill string of a new diameter needs to be loosened. A breakout wrench which has Interchangeable jaws for different drill rod diameters, allowing for the replacement of these jaws, would eliminate the need of using different wrenches for each diameter of drill rod, saving time and costs, and greatly advancing the field.
SUMMARY OF THE INVENTION
The main object of this invention is to obtain a novel breakout wrench with a compact and practical concept to facilitate the parts replacement and maintenance processes when loosing drill strings of different diameters in blasthole drill rigs.
This Breakout Wrench can be achieved by combining some or all of the following elements:
- a) An Alligator Wrench design having a Main Body, a Main Arm and a Torque Arm.
- b) A Wrench Support that can be permanently fixed to the surface of a blasthole drill.
- c) A Main Shaft connecting the Wrench Support to the Main Body and which is the turning point of the Wrench's Main Body.
- d) Holder Inserts
- e) Interchangeable Jaw Kits, each having two Jaw Holders, a Backing Jaw, a Torque Jaw, and a Grip Jaw, for at least three drill rod diameters, which leaves the Wrench 100% compatible to operate with different diameters, just by changing the Jaw Kits.
- f) A Split pin with an automatic sequence of movements, including approaches (turns), rod tightening, and exponential torque combined with pressure from two hydraulic cylinders, which act with built-in sequential valve regulation, as well as automatic adjustment that considers the wear in the external diameter of the rod.
- g) A Grip Cylinder, which has the purpose of gripping or tightening the rod.
- h) A Positioning Cylinder, for positioning the wrench, moving it towards the rod.
- i) A Torque Cylinder, for rotation and torque, which works in conjunction with the Positioning Cylinder to loosen and release the strings.
- j) A Sequential Valve specially designed for this wrench.
- k) A Traction Spring, which keeps the Torque Arm with a tendency to open.
- l) Support for the Torque Cylinder fixed to the Wrench Support.
And
- m) Support for the Sequential Valve fixed to the wrench's Main Body.
The design of the breakout wrench aims to optimize spaces and to order related peripherals, for example, hydraulic hoses, considering cylinder design to be able to leave the connection of the hoses only in the rear area of the wrench, therefore allowing for the cleaning of its upper front area. With this, it is also possible to focus the area of hose connections in a single sector of the wrench greatly facilitating the maintenance of this tool.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an embodiment of an Adjustable Breakout Wrench for Blasthole Drill Rods of Different Diameters in accordance with the present invention.
FIG. 2 is an exploded view of an embodiment of an Adjustable Breakout Wrench for Blasthole Drill Rods of Different Diameters in accordance with the present invention.
FIG. 3 is a perspective view of a partial assembly in an embodiment of an Adjustable Breakout Wrench for Blasthole Drill Rods of Different Diameters in accordance with the present invention, showing a removed Top Plaque.
FIG. 4 is a top view of an embodiment of an Adjustable Breakout Wrench for Blasthole Drill Rods of Different Diameters in accordance with the present invention, showing three different Jaw Kits for three different diameters of Drill Rods.
FIG. 5 is a top view of an embodiment of an Adjustable Breakout Wrench for Blasthole Drill Rods of Different Diameters in accordance with the present invention, showing two different positions of the wrench.
FIG. 6 is a partial perspective view of an embodiment of an Adjustable Breakout Wrench for Blasthole Drill Rods of Different Diameters in accordance with the present invention, showing an enlarged sectional view of a Totap Pin.
DETAILED DESCRIPTION AND BEST MODE OF IMPLEMENTATION
The Adjustable Breakout Wrench for Blasthole Drill Rods of Different Diameters subject of the present specification discloses a design that considers component ordering, to achieve a compact concept and above all practical for parts replacement and maintenance processes. The wrench works through an automatic sequence of movements, which are approaches (turns), bar tightening, and exponential torque combined with pressure from two hydraulic cylinders, which act with built-in sequential valve regulation, as well as automatic adjustment that considers the wear in the external diameter of the rod. This tool, which has the general shape of an alligator wrench, is designed to loose threaded rod joints used in drilling machines, being compatible to loose different diameters of Drill Rods, for example, 8⅝″, 9¼″, and 10¾″ diameter threaded drill rods used in drilling machines. For this purpose, it provides a practical and quick exchange of Jaw Holders, which have the preconceived dimensions to efficiently tighten each rod measure. The design of the key is provided, so that it can be mounted on the “PV-351” Drilling models. This tool is efficient, practical, easy to maintain and above all versatile so that it can operate in drilling production with different diameters of rods, only making simple changes of components without disassembling the wrench from its support.
Some general aspects of the present invention have been summarized so far in the first part of this detailed description and in the previous sections of this disclosure. Hereinafter, a detailed description of the invention as illustrated in the drawings will be provided. While some aspects of the invention will be described in connection with these drawings, it is to be understood that the disclosed embodiments are merely illustrative of the invention, which may be embodied in various forms. The specific materials, methods, structures, and functional details disclosed herein are not to be interpreted as limiting. Instead, the intended function of this disclosure is to exemplify some of the ways—including the presently preferred ways—in which the invention, as defined by the claims, can be enabled for a Person of Ordinary Skill in the Art. Therefore, the intent of the present disclosure is to cover all variations encompassed within the spirit and scope of the invention as defined by the appended claims, and any reasonable equivalents thereof.
As FIG. 1 shows, the Wrench Support 1 is attached to a Base Plaque 1a, through Fasteners 17. Said support has a Main Shaft 1b, which is the turning point of the wrench's Main Body 2. This Main Shaft 1b can be made, in some embodiments, of tempered “SAE 4340 steel” and is shown in FIG. 2. This Base Plaque 1a, at the same time can be attached or welded to the base of a drilling machine. The wrench's Main Body 2 has a Top Plaque 3 and a Bottom Plaque 4 between which different elements of this Main Body 2 are placed. These elements include a Torque Arm 5 and a Main Arm 6, each of which pivot around a Total Pin 16 to form an alligator wrench activated by the action of extension and contraction of a Grip Cylinder 7. This Top Plaque 3, Bottom Plaque 4, Torque Arm 5 and Main Arm 6 can be made, in some embodiments, of “A-572 structural steel”.
Three Holder Inserts 10c are shown, and so is a Jaw Kit, formed by, two Jaw Holders 10a and 10b, and three Jaws 11a, 11b and 11c. Those Holder Inserts 10c can be made of steel with heat treatment, which increases its toughness and the lifetime of parts, and a welding process can be considered, with a protocol that includes heat treatment to reduce the risk of fractures. One of those Holder Inserts 10c is designed to hold the Backing Jaw 11e, while the other two Holder Inserts 10c are designed to respectively hold the First Jaw Holder 10a to which the Grip Jaw 11a can be attached, and the Second Jaw Holder to which the Torque Jaw 11b can be attached. These Jaw Holders, 10a and 10b, and these Jaws 11a, 11b and 11c, are easily removable and replaceable respectively by other Jaw Holders, 10a and 10b, and other jaws 11a, 11b and 11c of different sizes in order to be able to adapt to the different diameters of drill rods as will be shown later in FIG. 4. A Traction Spring 12, which keeps the torque wheel always with a tendency to open, can also be seen in this figure, as well as a Sequential Valve 14 which is mounted to a Sequential Valve Support 13, and the Hydraulic Hoses 15. For the Wrench Support 1 and the Sequential Valve Support 13, “A-572 structural steel” is considered.
FIG. 2 shows an exploded view of the wrench for a better visualization of its parts. In it, it can be seen how the Main Shaft 1b connects the Wrench Support 1 to the Main Body 2 and also how the Wrench Support 1 is designed to be fixed without problems on a drilling machine's surface and attached to the Base Plaque 1a through Fasteners 17 and/or by welding. The three Hydraulic Cylinders used for this wrench can also be seen here: the Grip Cylinder 7, which has the purpose of gripping or tightening the rod, the Positioning Cylinder 8, for positioning the wrench, moving it towards the rod, and the Torque Cylinder 9, for rotation and torque, which works in conjunction with the Positioning Cylinder 8 to loosen and release the threads. The Sequential Valve Support 13 for the Sequential Valve 14 can be fixed to the wrench's Main Body 2, for example, by means of hexagonal head bolts. This Sequential Valve Support 13 can be fixed and removed in a practical and quick way. In addition, this support can be easily modified for valves of another sequence. This figure also shows a plurality of Total Pins 16, Fasteners 17, Washers 18a and Nuts 18b used to fasten and adjust the different parts of the tool.
In FIG. 3 the Top Plaque 3 has been removed for a better view of the internal elements of the wrench and how they are located relative to one another in the shown embodiment. Variations in shape, materials and design are possible without departing from the spirit and scope of the present invention. The position of the Traction Spring 12 can be seen here, which attracts the Torque Arm 5 towards the Wrench Support 1, keeping the Torque Jaw Holder 10b separated from the Grip Jaw Holder 10a. This Traction Spring 12 is important to maintain efficient operation in every tightening and torque action. For this reason, the replacement must be done quickly and conveniently, having a fastening system easy to release, for example through the use of a Parker Hardened bolt. This figure is also good for understanding the positions of the three Hydraulic Cylinders 7, 8 and 9, when the wrench is assembled.
FIG. 4 shows one of the characteristic features of this invention, and that is how the Jaw Kits can be replaced to adapt to different sizes of drill rods. In this example, a first Drill Rod 19a, having a first Diameter 20a is positioned within a first set of Jaws 11aa, 11ba and 11ca, supported by a first set of Jaw Holders 10aa and 10ba. These are adapted to the diameter 20a of the Drill Rod 19a, so that the wrench using these Jaws can adequately grip and loosen this Drill Rod 19a. But these Jaws are interchangeable for Jaws adapted to other Drill Rod Diameters. This makes the wrench 100% compatible to operate with different bar diameters, just by changing the Jaws, for example, with diameters of 8⅝″, 9¼″ and 10¾″ respectively. A second and a third Jaw Kits that can be interchanged are shown. The second set of Jaws 11ab, 11bb and 11cb, supported by a second set of Jaw Holders 10ab and 10bb is adapted to the Diameter 20b of the Drill Rod 19b, while the third set of Jaws 11ac, 11bc and 11cc, supported by a third set of Jaw Holders 10ac and 10bc is adapted to the Diameter 20c of the Drill Rod 19c. To change one set of Jaws for another one, a simple removal of the fasteners that attach the Jaw Holders to the Jaw Kit Holder Inserts 10c is needed. For example, in one embodiment, changing is done by loosening “Grade 12.9 Parker bolts”, and removing standard split tube pins. The Jaw Holders 10aa to 10bc can be made entirely in CNC machining, made of tempered steel “SAE 4340”, with heat treatment, hardness of 55 HRC. The Grip Jaws 11aa to 11ac and the Torque Jaws 11ba to 11bc can be made 100% on a CNC machine, made of tempered steel, with heat treatment, final hardness of 55-58 HRC, while the Backing Jaws 11ca to lice can be made on a CNC machine, “T-500” steel. As fasteners, Parker bolts “grade 12.9” can be used. The Jaw Kit Holder Inserts 10c can be made of tempered steel, with heat treatment, final hardness of 45 HRC, welded with optimal welding protocol to avoid altering the hardness.
FIG. 5 illustrates the functioning of the moving parts of the wrench, with different positions of the Hydraulic Cylinders and the corresponding displacement of the Torque Arm 5 and the Main Arm 6, resulting in the pressure needed to loosen the Drill Rod 19a. In the first half of the figure, the Grip Cylinder 7 is open and contracted, and the Drill Rod 19a is placed between the Jaws. The Torque Arm 5 has an Angle of Rotation 22 in relation to the Main Arm 6. There is a range of motion that this Angle can take, in function of the level opf extension and contraction of the three Hydraulic Cylinders, and that will determine the pressure exerted on the Drill Rod 19a, to grab it and loosen it. When the Grip Cylinder 7 moves towards the center and expands, as shown in the second half of the figure, the Torque Arm 5 rotates pivoting on the Total Pin 16a, generating a variation of the Angle of Rotation 21 of the Main Arm 6, resulting in a tighter grip of the Drill Rod 19a. These movements are regulated by the Sequence Valve 14 and the fluids needed to generate these movements flow through the Hydraulic Hoses 15.
Lastly, FIG. 6 shows the detail of the Total Pins 16. They can be made of “SAE 3115” tempered steel, subject to deep carburizing heat treatment. These Total Pins 16 connect to an internal lubrication system, as can be seen in this figure, in the sectional enlargement of the Total Pin 16a, in which the Lubrication Channels 23 can be seen, and which has a thread to connect to grease fittings. These Total Pins 16, in some embodiments, can be attached and secured with Segers rings (commercial).
The description as set forth is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of the teachings above without departing from the spirit and scope of the forthcoming claims.