Patent Application
20210270590
The invention relates to a booster assembly for use in drill and blast operations.
The drill and blast process used on many mining sites involves a number of operations that are carried out by mine personnel on a pit floor.
There are safety risks for the mine personnel when on a pit floor. The safety risks are compounded when mining operations are carried out in extreme conditions, such as in mines located in very hot and in very cold regions. The safety risks are also compounded when mining in and around pits where there is geothermal activity and the surface of the pit floor is hot and unstable and the pit temperature increases with depth. When mining in these pits, by way of example there can be unpredictable geysers in drilled holes, with hot water/steam being projected upwardly.
The applicant is involved in a research and development project to minimise the above-described safety risks.
As part of the project, the inventors of the subject invention have invented an initiation system vehicle for delivering a detonation device for initiating an explosion of an explosives material, such as a bulk explosive, in a hole in a pit floor as part of a drill and blast operation. The detonation device typically contains a small charge of explosive material. The detonation device is hereinafter referred to as a “booster”.
More specifically, the term “booster” as used herein is understood to refer to a detonation device typically containing a small charge of explosive material that can be located in a blast hole for the purpose of initiating an explosion of an explosive, such as a bulk explosives material, in the blast hole. In a situation where the booster contains an explosive material, the explosive material may be a charge of liquid or solid explosive of a fixed quantity that is calculated to detonate a fixed volume of explosive emulsion (or other suitable form of explosive formulation) within a primed drilled hole in a pit floor.
The inventors have also invented a booster assembly as described herein that comprises a booster and is suitable for use with the initiation system vehicle but is not exclusively limited to use with the vehicle.
The above description is not an admission of the common general knowledge in Australia and elsewhere.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods, devices, and materials similar or equivalent to those described herein can also be used in the practice or testing of the present invention, a limited number of the exemplary methods, devices, and materials are described herein.
In broad terms, the invention provides a booster assembly for use in a drill and blast operation, comprising in co-axial alignment:
In more particular terms, the invention provides a booster assembly for use in a drill and blast operation comprising in co-axial alignment:
The booster may contain a charge of an explosive for initiating the explosion of the bulk explosive in the hole in the pit floor.
The booster and the spool may have complementary formations that allow the spool to receive and locate the booster and thereby seat the booster on the spool.
The booster may be seated on the spool by being releasably coupled to the spool so that, in use, the booster is coupled to the spool in the storage position and can be moved clear of the spool as part of a process for moving the booster to the operative depth in the hole.
The booster and the spool may have complementary formations that allow the booster and the spool to be releasably coupled together by positively docking the booster on the spool and allow the booster to be released from the positive docking and moved clear of the spool as part of the process for moving the booster to the operative depth in the hole. With this arrangement, in use, the booster, spool and stake of the booster assembly may be moved together as a unit from the storage position to a position proximate the hole.
The booster may comprise a booster casing, for example for containing an explosives charge.
The booster casing may have an engagement feature, such as a collar, that facilitates engagement of the booster with a delivery assembly, for example that forms part of an initiation system vehicle, for transporting the booster assembly to a delivery position directly above the hole.
The spool may comprise a spool casing having an engagement feature, such as a collar, that facilitates engagement of the booster assembly with the delivery assembly for transporting the booster assembly to an intermediate transfer position proximate the delivery position directly above the hole. With this arrangement, in use, the delivery assembly can transport the booster to the loading position directly above the hole, with the spool and the stake remaining at the intermediate transfer position.
The delivery assembly may be any suitable assembly for transporting the booster assembly.
By way of example, the delivery assembly may be part of the initiation system vehicle that is described in a co-pending International application entitled “A mining vehicle” filed in the name of the applicant on the same day as the subject application. The purpose of the initiation system vehicle is to transport a plurality of booster assemblies on a pit floor and deliver a booster of each booster assembly in turn to an operative depth in a hole in the pit floor with an operator located in a cabin of the initiation system vehicle or operating the initiation system vehicle remotely or with the vehicle operating autonomously so that the booster can be inserted into the hole without mine personnel having to stand on the pit floor.
The spool may have a brake to control the release of the detonation cord.
The stake may be connected to the spool so that the spool and the stake are movable as a unit.
The spool and the stake may be separately formed as two components that are connected together.
The spool and the stake may be connected together so that the spool can rotate about a central axis of the stake.
The spool may include a central cavity extending axially upwardly from a lower end of the spool that receives the stake.
The stake may include an elongate shank that is received in the cavity of the spool and supported for rotation about a central axis of the shank.
The booster may have formations that allow the booster to receive and locate a pusher element of the delivery assembly for applying a downwardly-acting force to move the booster downwardly from the delivery position into the hole to the operative depth.
The booster and the pusher element may be formed so that the pusher element can be releasably coupled to the booster.
The pusher element may be releasably coupled to the booster by forming the booster with formations that allow the pusher element to be positively docked with the booster.
The formations may include a recess in an upper end of the booster that can receive the pusher element.
The initiation system vehicle that is described in the above-mentioned co-pending International application in the name of the applicant filed on the same day as the subject application comprises:
The loading assembly may comprise the pusher element for applying the downwardly acting force to move the booster into the hole to the operative depth.
The downwardly acting force may be a downward force applied via the pusher element to the booster to move the booster into the hole.
The downwardly acting force may be a consequence of the weight of the pusher element and the booster whereby the booster can move downwardly via a gravitational force pulling the booster into the hole to the operative depth.
The pusher element may be formed to (a) couple the booster and the pusher element together to support the booster while the pusher element, in use, moves the booster downwardly into the hole to the operative depth in the hole and (b) release the booster from the pusher element when the booster is at the operative depth so that the pusher element can be withdrawn from the hole.
The delivery assembly may comprise an arm that is moveable to transport the booster from the storage assembly to the loading assembly.
The arm may comprise a retaining member for example in the form of grippers that can engage and retain the booster while the arm, in use, transports the booster from the booster storage assembly to the booster delivery position.
The arm may be pivotally mounted for movement about a vertical axis for transporting the booster from the storage assembly to the loading assembly.
The storage assembly may be adapted to store a plurality of the booster assemblies.
The storage assembly may comprise a plurality of upwardly-extending storage tubes for receiving and retaining the booster or booster assembly, with one booster or booster assembly per tube.
The storage assembly may comprise a lifting assembly for lifting each booster or booster assembly upwardly to an extended position such that the booster extends at least partially from the tube,
Each storage tube may include an internal guide that can slide in the tube and is adapted to receive and support a lower end of the booster assembly in the tube.
The internal guide may be adapted to receive and support a lower end of the stake of the booster assembly in the tube.
The internal guide may include an outer surface that has a diameter that is marginally less than a diameter of an internal wall of the tube and, in use, contacts the inner wall and facilitates sliding movement of the guide in the tube.
The internal guide may include a pair of spaced apart collars that have the above-described outer surfaces that, in use, contact the inner wall and facilitate sliding movement of the guide in the tube.
The spacing between the collars may be selected so that the guide can move in a stable way within the tube.
The internal guide may include a cavity extending from an upper wall of the guide for releasably receiving and supporting the stake. With this arrangement, the stake can be lifted clear of the internal guide when the booster assembly has been lifted to a raised position in the tube.
The storage assembly may comprise a platform that is arranged to rotate about a central upright axis, with the platform supporting the tubes. Rotation of the platform moves the tubes (and the boosters in the tubes) into a loading position. The tubes are open-ended, with the lower ends aligned with openings in the platform.
Various features, aspects, and advantages of the invention will become more apparent from the following description of embodiments of the invention, along with the accompanying drawings in which like numerals represent like components.
Embodiments of the invention are illustrated by way of example, and not by way of limitation, with reference to the accompanying drawings, of which:
Embodiments of the booster assembly of the invention are now described more fully hereinafter with reference to the accompanying drawings, in which various embodiments, although not the only possible embodiments, of the invention are shown. The invention may be embodied in many different forms and should not be construed as being limited to the embodiments described below.
The embodiments of the booster assembly of the invention are described in the context of use with embodiments of initiation system vehicle (“ISV”) of the invention of the co-pending International application mentioned above.
As shown in
With further reference to
It is noted that the booster assembly of the invention is not confined to use with these vehicles.
With reference to
Each of the booster 65, the spool 63, and the stake 61 may be any suitable dimensions and made from any suitable materials.
As is described below, in embodiments of the invention in which the booster assembly 60 is to be used with the above-mentioned ISV and is stored in an upwardly-extending storage tube (not shown), the booster assembly 60 includes two axially-spaced apart collars 79 with outermost surfaces 83 having diameters that are selected to be marginally less than an inner diameter of the tube so that the booster assembly 60 can be snuggly stored in the tube and can slide in the tube.
As can best be seen in
A base 74 of the booster 65 (see
The spool 63 has a central neck 63a around which the detonation cord 66 (not shown in
As can best be seen in
The stake 61 has an elongate shank 75 and a pointed end 77 and is a robust structure for anchoring the spool 63 and attached detonation cord 66 to the pit floor 91 proximate a safe hole 90a in preparation for tie-in, as described above in relation to
The stake 61 is connected to the spool 63 so that the spool 63 and the stake 61 are movable as a unit. The spool 63 and the stake 61 may be separately formed as two components that are connected together. The shank 75 of the stake 61 is received in the cavity 91 of the spool 63 and supported via bearings 87 so that the spool 63 can rotate about a central axis of the shank 75 and thereby, in use facilitate the detonation cord 66 unwinding from the spool 63 as the booster 65 is positioned in the hole 90 in the pit floor 91—see
The head of the spool 63 and the head of the booster 65 have the same neck profile 71 so that the spool 63 and the boosters 65 can cooperate with the same gripping mechanism (not shown) of a delivery assembly of the above-mentioned ISV.
The spool 63 and the booster 65 have the same-shaped recess 67 to allow a pusher 41 of a delivery assembly of the above-mentioned ISV to separately engage with the spool 63 and the booster 65. The engagement of the pusher 41 and the booster 65 is illustrated in the embodiment of the booster assembly shown in
When used with the above-mentioned ISV, a plurality of booster assemblies 60 are stored in a suitable bomb-proof magazine or other suitable storage assembly of the ISV. The ISV is driven to a location proximate a hole 90 in the pit floor 91 shown in
A loading assembly of the ISV (i) supports the booster 65 in the delivery position above an opening 94 to the hole 90 and (ii) moves the booster 65 downwardly into the hole 90 via movement of the pusher element 41 and inserts the booster 65 at an operative depth in the hole 90.
The embodiment of the booster assembly shown in
The spool 63 and the stake 61 are identical to the same components in the embodiment shown in
The booster 65 is different. Specifically, the booster 65 is the same booster 65 as the booster of the embodiment shown in
In the following description of
The booster 65 shown in
In the booster 65′ shown in
A base 74, 74′ of the boosters 65, 65′ provides a rounded protrusion that in use cooperates with the engagement recess 67 that forms a booster dock 69 in the spool 63—for example, see
The upper and lower portion of each booster 65, 65′ are identical to facilitate engagement with a common spool 63 and a pusher element 41 of a delivery assembly, as described below.
The spool 63 of the booster assembly 60 shown in
With reference to
With reference to
The head of the spool 63 and the heads of the booster 65, 65′ have the same neck profile 71 so that the spool 63 and each of the boosters 65, 65′ can cooperate with the same gripping mechanism of a delivery assembly.
The spool 63 and the booster 65, 65′ have the same shaped recess 67 to allow the pusher 41 of the delivery assembly to engage with the spool 63 and each of the boosters 65, 65′. The engagement of the pusher 41 and the booster 65 is illustrated in
The booster engagement mechanism 49 of the pusher 41 of the delivery assembly is illustrated in
The pusher 41 is an elongate element with an upper end and a lower end as evident from
A large portion of the internal volume of the pusher 41 is filled with ballast 105, for example lead, to increase the weight of the pusher 41 and to assist the booster 65 moving downwardly through the explosive emulsion 93 (
The booster engagement mechanism 49 is located in a lower section of the pusher 41.
The pusher 41 includes a chamber 117 in a lower section of the pusher 41. The chamber 117 is defined by a section 119 of the side wall 121 of the pusher 41, an upper partition member 123 that separates the chamber 117 and the ballast 105, and lower end element 125.
The pusher 41 also includes a plate 75 that is arranged for sliding movement along the length of the chamber 117. The plate 75 divides the chamber 117 into an upper chamber 117a and a lower chamber 117b.
The pusher 41 also includes a spring 43 in the upper chamber 117a. The spring 43 is selected so that it can extend axially downwardly and compress axially upwardly in response to sliding movement of the plate 75 in the chamber 117.
As can best be seen in
The pusher 41 also includes a cylindrical actuator 45 that is connected at one end to the plate 75 and at the other end to the above-mentioned conical nose 46. The actuator 45 extends through an opening in the lower end element 125.
In addition, the pusher 41 includes a compressible member 48 that is mounted along a section of the length of the actuator 45 between the nose 46 and an end plate 75.
As can be appreciated from
Under normal operating conditions, it is necessary to supply air to the pusher 41 in order to couple together the booster 65 and the pusher 41. It is noted that when there is no air supply to the pusher 41, the pusher 41 will automatically decouple form the booster 65.
In use, in order to couple the pusher 41 to the booster 65, the pusher 41 and booster 65 are first axially aligned.
The conical nose 46 of the pusher 41 is then inserted into the recess 67 of the pusher dock 79 of the booster 65 until it cannot move forward from this engaged position—as shown in
Compressed air is then fed into the inlet 44 and downwardly through the central tube 115 and into the lower chamber 117b. The air increases the pressure in the lower chamber 117b and causes the plate 75 to move upwardly in chamber 117 against the action of the spring 43. This upward movement of the plate 75 cause the actuator 45 and the nose 46 to move upwardly, thereby causing the compressible member 48 to be compressed in an axial direction and expanded outwardly in a radial direction. As the compressible member 48 expands in a radial direction the friction between the recess 67 and the compressible member 48 is increased locking the pusher 41 to the booster 65, illustrated in the coupled mode of
To decouple the pusher 41 from the booster 65, the compressed air source (not shown) is de-activated, and reduces the pressure in chamber 117b, at which time the return spring 43 expands, pushing plate 75 downwardly and the actuator 45 away from the pusher 41 and allowing the compressed member 48 to expand in an axial direction and contract in the radial direction, reducing the friction between the recess 67 and the compressible member 48 and releasing the booster 65 from the pusher 41, illustrated in the decoupled mode of
It is apparent from the above description that the booster assembly 60 of the invention makes it possible to efficiently and effectively transfer a booster 65 of the assembly 60 from a storage location to the hole 90 in the pit floor. In particular, it is apparent from the above description that the spool 63 and the stake 61 of the assembly 60 are important components of the booster assembly 60.
It will be appreciated by persons skilled in the art that numerous variations and modifications may be made to the above-described embodiments, without departing from the scope of the following claims. The present embodiments are, therefore, to be considered in all respects as illustrative of the scope of protection, and not restrictively.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present invention, a limited number of the exemplary methods and materials are described herein.
It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country.
In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2018902370 | Jun 2018 | AU | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/AU2019/050690 | 6/28/2019 | WO | 00 |
