Primer delivery systems and methods

Abstract

The present disclosure describes a system and method for delivering a primer to an operating depth to detonate an explosive in a blast hole. The system described herein may include a cap structure providing access to the hole and a separable detonator subassembly that is deployed to deliver the detonator to a pyrotechnic location. A method of pyrotechnic a blast hole includes installing such a system at the open edge of the blast hole and deploying the detonator assembly simultaneously with loading the explosive into the blast hole.

Description

Related Applications

[0001] This patent application is related to and claims priority to Australian Provisional Patent Application No. 2022900487, filed on March 1, 2022, entitled "Primer Delivery System and Method", which is incorporated herein by reference in its entirety. [Technical field]

[0002] The present disclosure describes systems and methods in the field of blasting operations. More specifically, the present disclosure describes systems and methods for delivering a primer to an operating depth to trigger the detonation of an explosive within a blast hole. Summary of the Invention

[0003] According to one aspect of the present invention, there is provided a system for priming a blast hole, comprising: Cap and a detonator subassembly including a detonator holder configured to fix a detonator in a pyrotechnic orientation, the detonator holder having an undeployed state and a deployed state; Equipped with The cap, a cap body having a top side, a bottom side, and a spool chamber disposed therein; an aperture extending through the bottom side and centrally disposed with respect to the spool chamber; a hollow guide tube in communication with the aperture and aligned with the axis of the aperture, the guide tube having an upper end fixed to the bottom side of the cap body and a lower end opposite the upper end; Equipped with In the undeployed state, the detonator holder is removably fixed to the lower end of the guide tube, and in the deployed state, the detonator holder is separated from the guide tube. A system is provided.

[0004] In some embodiments, the detonator subassembly comprises a detonator secured to a detonator holder, and a conductor having a detonator end coupled to the detonator and a connector end opposite the detonator end, the conductor being substantially disposed within the spool chamber in the undeployed state.

[0005] In some embodiments, at least a portion of the conductor is wound within the spool chamber.In some embodiments, at least a portion of the conductor is wound on a spool disposed within the spool chamber.

[0006] In some embodiments, the spool chamber allows the lead to unravel and be routed through the aperture and guide tube in the deployed state.

[0007] In some embodiments, the connector end includes a connector configured to connect the conductor to a source of the detonation signal, hi some embodiments, the connector comprises one of a wireless receiver module, a direct electrical connection, and a mechanical connection.

[0008] In some embodiments, the wire is one of a detonating cord, an electrical wire, or a shock tube.

[0009] In some embodiments, the cap body has a generally circular shape.

[0010] In some embodiments, the spool chamber includes a hub. In some embodiments, the hub surrounds the aperture. In some embodiments, the hub is circular or cylindrical. The hub may be hollow and may define a passage therethrough. In some embodiments, the hub is integrally formed with the cap body. In other embodiments, the cap body and the hub may be formed separately and the hub may be secured or connected to the cap body. In some embodiments, the cap body and the hub are concentrically disposed with respect to one another.

[0011] In some embodiments, the height of the hub is less than the height of the cap body. In some embodiments, the bottom edge of the hub is aligned with the bottom edge of the cap body. In some embodiments, the top end of the hub is below the top edge or top side of the cap body, which can facilitate routing the electrical leads through the aperture and passageway defined by the hub.

[0012] In some embodiments, the detonator holder is at least partially housed within the lower end of the guide tube in an undeployed state, hi some embodiments, the detonator holder is frictionally secured within the lower end.

[0013] In some embodiments, the detonator subassembly is configured to be coupled to an explosive delivery hose.

[0014] In some embodiments, the spool chamber is open for access through an upper side of the cap body, hi some embodiments, the upper side of the cap body includes a removable lid.

[0015] In some embodiments, the detonator holder further comprises a retention structure configured to interact with the walls of the blast hole to maintain the detonator holder in the deployed position within the blast hole or to resist movement of the detonator holder away from the deployed position.

[0016] In some embodiments, the retaining structure comprises one or more arms extending radially from the detonator holder to engage the walls of the blast hole, hi some embodiments, the retaining structure provides greater resistance to movement of the detonator holder in one direction within the blast hole versus movement in the opposite direction.

[0017] In some embodiments, the guide tube is sized to be received within the lip of the blast hole with a friction fit sufficient to secure the cap. In some embodiments, the guide tube has an outer diameter of about 50 mm to about 300 mm, more specifically, about 50 mm to about 150 mm, about 55 mm to about 80 mm, about 60 mm to about 75 mm, about 75 mm to about 300 mm, or about 100 mm to about 250 mm.

[0018] In accordance with another aspect of the present invention, there is provided a method for priming a blast hole, comprising the steps of: Providing a system as disclosed herein; placing the cap body on an edge of the blast hole opening such that the guide tube and detonator subassembly are directed into the blast hole; advancing an explosive delivery hose through the aperture and guide tube to push the detonator subassembly away from the detonator holder into a deployed position in the blast hole; withdrawing the delivery hose from the deployed position and disconnecting the delivery hose from the detonator holder; A method is provided comprising:

[0019] In some embodiments, an explosive delivery hose is coupled to the detonator subassembly as it advances through the aperture.

[0020] In some embodiments, the method further comprises discharging the explosives into the blast hole via a delivery hose.

[0021] In some embodiments, the detonator subassembly detaches from the explosive delivery hose by releasing the explosive.

[0022] In some embodiments, the method further comprises connecting the connector end to a source of a detonation signal.

[0023] In accordance with another aspect of the present invention, there is provided a system for priming a blast hole, comprising: a cap, a detonator subassembly, and a conductor; The cap, a top side, a bottom side, and a spool chamber disposed therein; an aperture extending through the bottom side and centrally disposed with respect to the spool chamber; a hollow guide tube in communication with the aperture and aligned with the axis of the aperture, the guide tube having an upper end fixed to the bottom side of the cap body and a lower end opposite the upper end; Equipped with The detonator subassembly is A detonator holder that fixes a detonator in a pyrotechnic orientation and has an undeployed state and a deployed state Equipped with a conductor having a detonator end coupled to the detonator and a connector end opposite the detonator end, at least a portion of the conductor being wound within the spool chamber in an undeployed state; In the undeployed state, the detonator holder is removably fixed to the lower end of the guide tube, and in the deployed state, the detonator holder is separated from the guide tube. A system is provided.

[0024] Unless the context clearly indicates otherwise, throughout this specification and the claims, the words "comprise", "comprising" and similar words are to be interpreted in their inclusive sense, i.e. "including, but not limited to", rather than in their exclusive or exhaustive sense.

[0025] The embodiments disclosed herein will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings, which depict only exemplary embodiments and which will be specifically described in detail with the aid of the accompanying drawings. [Brief description of the drawings]

[0026] [Figure 1A]FIG. 2 is a perspective view of a primer delivery system according to an embodiment. [Figure 1B] FIG. 1B is an exploded perspective view of the primer delivery system of FIG. 1A. [Figure 1C] FIG. 1B is a cross-sectional view of the primer delivery system of FIG. 1A. [Diagram 2] FIG. 2 is a perspective view of components of a primer delivery system according to an embodiment. [Figure 3A] 1B illustrates a method of using the system of FIG. 1A, according to an embodiment. [Figure 3B] The next step in the method of use shown in FIG. 3A is shown. [Figure 3C] The next step in the method of use shown in Figures 3A and 3B is shown. [Figure 3D] 3A to 3C. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the accompanying drawings, specific embodiments of the present disclosure that may be implemented are illustrated. These embodiments are described in sufficient detail to enable one skilled in the art to practice the invention. It is to be understood that other embodiments may be utilized, and that structural, logical, and electrical changes may be made within the scope of the present disclosure. From the following description, it is to be understood that the components of the embodiments, as generally described and illustrated, may be arranged and designed in a wide variety of different configurations. Thus, while various embodiments as illustrated in the drawings will be described in more detail below, the descriptions are not intended to limit the scope of the present disclosure, but are merely representative of various embodiments. While various aspects of the embodiments are illustrated in the drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

[0028] The terms "connected to" and "coupled to" refer to any type of interaction between two or more entities, including mechanical, electrical, magnetic, electromagnetic, fluid, and thermal interactions. Two components may be connected or coupled to one another even if they are not in direct contact with one another. For example, two components may be coupled to one another through an intermediate component or by a magnetic signal.

[0029] One of the operations in the drilling and blasting process involves placing a primer in the blast hole. The primer typically contains a small amount of explosive. The purpose of the primer is to trigger the detonation of the explosive, e.g., bulk explosive, in the blast hole. Hereinafter, the primer will be referred to as a "primer."

[0030] More specifically, the term "primer" as used herein refers to a structure that typically contains a small amount of explosive and is understood to be placed in a blast hole for the purpose of inducing the detonation of the explosive therein. The primer may comprise or consist of a detonator configured to explode upon receiving an initiation signal. As used herein, the term "initiation signal" refers to any short-term phenomenon that typically is transmitted by some type of conductor and directly or indirectly induces an explosion. The signal itself may be an explosive impulse generated by another explosive, an electric current, or an electronic communication, each of which may be transmitted to the detonator by a suitable conductor operatively connected to the detonator. The primer may further comprise an additional explosive that is more sensitive to the detonation of the detonator than a bulk explosive.

[0031] Effective priming of blast holes at a blast site can involve many operational challenges. Priming materials can contain sensitive explosives, and direct handling of such materials during transportation and installation can result in injury to personnel. Manual delivery of primers deep enough into blast holes for effective priming also involves similar risks, especially if the primer is dropped into the hole. Additionally, priming a large number of holes in a blast area can expose portions of many conductors above ground, requiring on-site personnel to use extreme caution to avoid disturbing the conductors when moving around the site.

[0032] Systems for pyrotechnic blastholes described herein may include structures configured to position a detonator and lead wire in an easily deployable position relative to the blasthole. In one aspect, this may include positioning the lead wire such that one end of the lead wire coupled to the detonator can be easily moved downhole while the other end is accessible for incorporation into the blast initiation process. Various features of such systems may be readily understood with reference to the exemplary embodiments shown in FIGS. 1A-1C. With reference to the illustrations in these figures, the system 100 may include a cap 102 configured to be fixedly positioned at the open edge of a blasthole while positioning the primer for downhole deployment. For example, the cap 102 may include a cap body 104 having a shape and size such that it can seat across the width of the hole. As shown in FIGS. 1A and 1B, in some embodiments, the cap body 104 may have a generally circular or cylindrical shape. In some embodiments, the cap body may have other shapes including, but not limited to, a rectangle, a cross, a star, and an ellipse. The width or diameter of the cap body 104 may be set so that the cap 102 can span the width or diameter of the opening edge of the blast hole, thereby greatly reducing the risk of the cap 102 falling into the blast hole.

[0033] The cap 102 may further include a spool chamber 106 disposed within the cap body 104. The spool chamber 106 may be configured to accommodate the entire length of the conductor 108, the entire length being sufficient to reach a desired location in the blast hole. The spool chamber 106 allows the conductor 108 to be arranged in an orderly manner, such that the entire length of the conductor 108 may be introduced into the blast hole with little or no tangling or snagging. For example, as shown in each of FIGS. 1A-1C, the spool chamber 106 may accommodate the conductor 108 in a coiled state. It will be appreciated that such a coiled conductor 108 may have a corresponding coil height. The cap 102 may be configured to have a predetermined height, such that the spool chamber 106 formed within the cap 102 has a height sufficient to accommodate the coiled conductor 108 up to the predetermined coil height. As will be described in more detail below, this allows the cap 102 to be placed over the blast hole opening lip 14 during use, so that the cap body 104 and coiled wire 108 (contained within a spool chamber 106) are positioned to cover the blast hole.

[0034] In various embodiments, the spool chamber 106 may include one or more features to facilitate loading and winding of the conductor 108 therein. The cap body 104 may be configured to provide access to the spool chamber 106. For example, the cap body 104 may have a substantially open top 110, as shown in FIGS. 1A-1C, respectively, or a top 110 that includes a removable lid. In some embodiments, the spool chamber 106 may have a centrally located hub, and the conductor 108 may be wound around the hub. In some embodiments, the walls of the spool chamber 106 may include ridges and / or grooves to support and stabilize the coil of conductor 108. In some cases, the conductor 108 for use in blasting applications may be obtained in a pre-wound spool. In some embodiments, the spool chamber 106 is configured to allow such a spool to be placed therein.

[0035] In the illustrated embodiment, as shown most clearly in FIG. 1C , the cap body 104 has a retention structure in the form of an inwardly projecting (circular) lip or flange extending from, adjacent to, or associated with the top side 110 of the cap body 104 to prevent movement of the coiled conductor 108 away from the spool chamber 106 and to assist in retaining the coiled conductor 108 within the spool chamber 106. In the illustrated embodiment, the inwardly projecting lip or flange is circular and extends continuously around the top side 110 of the cap body 104. It will be understood that the retention structure is not limited to such a configuration and may have an interrupted configuration. For example, the retention structure may include one or more discrete elements spaced apart from one another around or adjacent the top edge of the cap body 10.

[0036] The lead 108 includes a detonator end 112 operatively connected to a detonator 114 adapted to initiate detonation of a main explosive, either directly or via an intermediate explosive. The lead 108 further includes a connector end 116 opposite the detonator end 112, configured to receive a blast initiation signal and transmit the signal to the lead 108, which then propagates to the detonator 114. The present disclosure encompasses systems for use with various blast initiation methods and apparatus. Various types of lead 108 may be used in the systems described herein. For example, a non-electrical detonator may be coupled to a non-electrical lead, such as a detonating cord or a shock tube. In other embodiments, an electric detonator may be coupled to an electric lead comprising one or more wires. In some embodiments, an electronic detonator, such as an electronic delay detonator, may be coupled to an electric lead or a non-electrical lead.

[0037] In some embodiments, the connector end 116 may include a connector 118 that connects the lead 108 to a source of detonation signal. The nature of the detonation signal and connector 118 will depend on the type of detonation approach used and the type of lead 108 and detonator 114 fired into the blast hole. For example, in a non-electrical detonation system using a propagating shock wave as the detonation signal, a non-electrical lead, such as a cord or shock tube, may be used and the connector 118 may provide a mechanical connection between the lead 108 and a suitable above ground mains. In an electrical detonation system, an electrical lead suitable for conducting the detonation signal to the detonator may be used. In such a case, the connector 118 may be configured to provide a direct electrical connection between the lead 108 and the electrical detonation circuit. In a wireless detonation system, the connector 118 may be a wireless receiver module that can participate in a wireless connection with a remote blast control unit.

[0038] The cap 102 may include an aperture 120 that provides access to the blast hole through the cap body 104. This access may be further facilitated by a hollow guide tube 122 secured to a bottom side 124 of the cap body 104. The guide tube 122 communicates with and is axially aligned with the aperture 120. As shown in FIGS. 1A-1C, the relative positioning of the coiled electric wire 108 and the aperture 120 allows the electric wire 108 to be unwound and fed through the aperture 120 and guide tube 122 of the cap body 104. Further, as previously described, this positioning allows the cap 102 to be positioned over the rim 14 of the blast hole with the cap body 104 and the coiled electric wire 108 contained within the spool chamber 106 positioned over the blast hole with the guide tube 122 directed into the blast hole.

[0039] In one embodiment, the guide tube 122 provides a path to guide the lead 108 as it leaves the spool chamber 106. In another embodiment, the aperture 120 and the guide tube 122 provide a path for loading the blast hole with explosives, such as bulk explosives. Bulk explosives include simple ANFO (ammonium nitrate + fuel oil), water-in-oil emulsions, water gels, and various mixtures thereof. These materials are often delivered to the blast hole in a somewhat flowable state, although they may be viscous and / or dense, and are discharged into the blast hole via a delivery hose. Thus, the aperture 120 and the guide tube 122 each have an inner diameter that allows the explosives delivery hose to pass easily through. More specifically, the inner diameters of these features are each large enough to simultaneously accommodate both the delivery hose 16 and the lead 108. The outer diameter of the guide tube 122 is suitably selected to allow the guide tube 122 to fit within the open lip of the blast hole. In some embodiments, the outer diameter of the guide tube 122 is selected to provide a friction fit with the edge of the blast hole opening to facilitate placement of the system 100. In various embodiments, the outer diameter of the guide tube 122 can be about 50 mm to about 300 mm, and more specifically, about 50 mm to about 150 mm, about 55 mm to about 80 mm, about 60 mm to about 75 mm, about 75 mm to about 300 mm, or about 100 mm to about 250 mm. In the illustrated embodiment, the outer diameter of the guide tube is smaller than the outer diameter of the cap body.

[0040] The system 100 may further comprise a detonator subassembly 126. The detonator subassembly 126 may be deployed to a desired pyrotechnic location within the blast hole, e.g., at the bottom of the hole for bottom-priming methods. In other words, the detonator subassembly 126 may perform at least two functions: 1) to removably secure the detonator 114 to the system 100 in an undeployed state, and 2) to be deployable to deliver the detonator 114 to a suitable pyrotechnic location within the blast hole and to secure the detonator 114 there until detonation. Thus, in addition to the detonator 114 itself, the detonator subassembly 126 may comprise a detonator holder 128 configured to secure the detonator 114 in a pyrotechnic suitable position. More specifically, the detonator holder 128 may secure the detonator 114 in an orientation such that the explosive charge of the detonator 114 faces the explosive. An example of this configuration is illustrated from various perspectives in Figures 1A-1C, in which detonator holder 128 is configured to hold detonator 114 in the proper orientation for bottom-hole priming.

[0041] The present disclosure encompasses detonator holders that can accommodate and deliver priming packages that include priming elements in addition to detonators. For example, in blasting applications involving explosives that are not sensitive to detonators, effective pyrotechnics involves the use of intermediate explosives that are sensitive to detonators, i.e., primers, and in some cases, additional explosives called boosters. Primers and combinations of primers and boosters are available as packaged units. In some embodiments, the detonator holder 128 is configured to hold such packages and the detonator in a mutual arrangement suitable for initiating the intermediate explosives with the detonator.

[0042] As noted above, the detonator holder 128 is deployable and transports the detonator 114 to a deployed position within the blast hole. Also, as noted above, the systems described herein may be configured to allow an explosives delivery hose to be introduced into the blast hole through the cap structure and remain in position while the bulk explosive is being loaded into the blast hole. In some embodiments, the systems are configured such that deployment of the detonator subassembly 126 is accomplished by a blast hole loading process. As shown in FIG. 1C, the detonator holder 128 may be removably secured to the guide tube 122 such that the detonator holder 128 is located in the path of the delivery hose as it passes through the guide tube 122. As a result, the delivery hose presses the detonator subassembly 126 against the guide tube 122 and removes the detonator subassembly 126 from the guide tube 122. The means for securing the detonator holder 128 to the guide tube 122 may provide a mount that is secured in the undeployed state but is easily unlocked by insertion of the delivery hose. 1A and 1C, the detonator holder 128 may be sized to fit within at least a portion of the guide tube 122, such as the distal end of the guide tube 122. In such a configuration, the relative sizes of the detonator holder 128 and the guide tube 122 may be selected such that the detonator holder 128 is frictionally secured in position. The use of other means of securing the detonator holder 128 in position, such as adhesives, snap-fit ​​structures, etc., is also encompassed by the present disclosure.

[0043] In some embodiments, the detonator subassembly 126 may include one or more features to couple to, fit over, or provide a more secure engagement with an end of a delivery hose during deployment. For example, the end of the detonator holder 128 may have a cylindrical recess. The recess is sized to receive, couple to, and / or fit over the end of the delivery hose when the end of the delivery hose contacts the detonator holder 128. In other examples, the end of the detonator holder 128 may include a protrusion (e.g., a cylindrical protrusion). The protrusion is sized to enter the end of the hose when the end of the hose contacts the detonator holder 128.

[0044] 2-3D show various embodiments of the system and its components described in relation to FIGS. 1A-1C. The illustrated embodiments may all have similar features. Accordingly, similar features are designated with similar reference numbers with an incremented leading numeral. Accordingly, the above and related disclosures may not be repeated hereafter with respect to features identified as being similar. Furthermore, certain features of the system and its related components shown in FIGS. 1A-1C may not be designated or identified in the drawings or specifically described in the following specification. However, such features may be clearly the same or substantially the same as features illustrated and / or described in relation to other embodiments.

[0045] In some embodiments, the detonator holder 128 may include one or more features to facilitate securing the detonator in a pyrotechnic position within the blast hole until detonation begins. For example, such features may be designed to prevent the detonator subassembly from moving back toward the edge of the opening, such as due to inadvertent tension on the lead or pressure from surrounding explosives. In some embodiments, the detonator subassembly 126 may include a retention structure that functions by interacting with a surface within the blast hole. FIG. 2 illustrates an embodiment of a detonator subassembly 226 that includes a detonator 214 connected to a detonator end 212 of the lead 208, the detonator 214 being secured to a detonator holder 228. The detonator holder 228 further includes a retention structure 240 that includes a plurality of arms 242 configured to interact with the wall of the blast hole in which the detonator assembly 226 is deployed. As shown, the arms 242 are configured to engage the walls of the blast hole, allowing the detonator subassembly 226 to move in one direction within the hole, but resist movement in the opposite direction. The arms 242 are configured to be spring loaded or otherwise bendable, expanding outward to press against the walls of the blast hole and resist movement of the detonator subassembly 226. This resistance also helps to control the descent of the detonator assembly during downhole priming, thereby reducing the risk of damage to the detonator assembly or premature detonation. The arms 242 may be oriented such that this pressure increases significantly when moving in an undesirable direction, such as back toward the edge of the opening. The retaining structure 240 also helps to center the detonator holder 228 within the blast hole. The retaining structure 240 shown in FIG. 2 illustrates one example of such a configuration, but it will be understood that other configurations that provide similar functionality are encompassed by the present disclosure.

[0046] The above system may be used to place primers in each blast hole at a blasting site and deliver the primers to a working position within the blast hole in a safe and effective manner. Such a system may be provided with a package of detonators and leads, facilitating safe handling and placement of these materials at the site. Such a system may improve site safety by allowing a large number of primer leads to be neatly placed while still providing easy access to these leads. Furthermore, the actual pyrotechnics of each blast hole do not require unreliable and dangerous manual deployment or the use of additional complex vehicles or machinery. Rather, the pyrotechnics may be performed as part of the process of filling the hole with bulk explosives.

[0047] 3A-3D show an example of the use of such a system, i.e., the system 100 shown in FIGS. 1A-1C, in a method of pyrotechnic blastholes. It is noted that while FIGS. 3A-3D show a vertically downward blasthole, the systems and methods described herein may also be used for holes oriented in other directions, such as upward or horizontal. The systems and methods may also be used in above- or below-ground blasting applications. As shown in FIG. 3A, the method may comprise placing the primer delivery system 100 in a blasthole 10 drilled in an earth formation 12. More specifically, the cap 102 is placed at the open edge 14 of the blasthole 10, the cap body 104 is placed over the blasthole 10, and the guide tube 122 and detonator subassembly 126 are directed into the blasthole 10. As shown in FIG. 3A, the cap body 104 may span the width of the blasthole 10 at the open edge 14. As shown, the guide tube 122 may extend into the blasthole 10 for some distance.

[0048] As shown in FIG. 3B, deployment of the detonator subassembly 126 may be performed in conjunction with a process of loading explosives into a blast hole. This process comprises introducing the delivery hose 16 into the blast hole 10 by advancing the delivery hose 16 through the cap body 104 and the guide tube 122 in the direction indicated by the arrow. The detonator holder 128 is separated from the guide tube 122 by the advancing delivery hose 16 and is forced against the end or bottom of the blast hole. The conductor 108 is released from a spool chamber (not shown), passes through the guide tube 122, and travels down the hole as the detonator holder 23 moves down or along the blast hole. In some embodiments, the relative sizes of the detonator holder 128 and the delivery hose 16 are selected such that the detonator holder 128 is pushed by the delivery hose 16 without catching or getting tangled in the end of the delivery hose 16. In certain embodiments, the relative sizes and configurations of the detonator holder 128 and the delivery hose 16 are such that the delivery hose 16 can be coupled or fitted to the end of the detonator holder 128 during insertion of the delivery hose 16 .

[0049] As shown in FIG. 3C, once the detonator subassembly 126 has advanced to a deployed position (e.g., the bottom of the blast hole 10 as shown), the delivery hose 16 may be withdrawn. This disengages the detonator holder 128 from the delivery hose 16 and leaves it below the blast hole 10. In some embodiments, while the delivery hose 16 is being withdrawn, as shown in FIG. 3C, the explosives 18 may be discharged through the delivery hose 16 into the blast hole 10. The discharge and withdrawal may begin at approximately the same time, or the discharge may begin at some point after the withdrawal begins. In certain embodiments, discharging the explosives 18 through the delivery hose 16 disengages the detonator holder 128 from the delivery hose 16. For example, the explosives 18 may be forced against the detonator holder 128, thereby disengaging the detonator holder 128 from its connection to the delivery hose 16.

[0050] As shown in FIG. 3D, after loading the explosives 18 and removing the delivery hose 16, the blast hole 10 is pyrotechnic. In some embodiments, the explosives may undergo a conditioning process in preparation for blasting. Conditioning processes include, but are not limited to, increasing reactivity and viscosity. Such processes may begin before or during the release of the explosives 18 into the blast hole 10, or may continue for some time thereafter. Stemming material may be introduced into the blast hole. In some embodiments, such material may be introduced into the blast hole through an aperture and a guide tube.

[0051] The method may further comprise connecting the detonator subassembly 126 to a source of a detonation signal 20 that propagates down the conductor 108 and detonates the detonator 114. In various embodiments, this connection may be made via a connector end (not shown) of the conductor 108, such as via a connector (not shown) operably connected thereto. The nature of the detonation signal may depend on the type of detonation method being used and the type of wire and detonator pyrotechniced in the blast hole. For example, in a non-electrical detonation system, the detonation signal 20 may be a propagating shock wave and a non-electrical wire such as a cord or shock tube may be used, and a mechanical connector may be used to connect the wire to a suitable aboveground mains. Electrical detonation may involve the use of an electrical wire suitable for conducting the detonation signal to the detonator. In such a case, the connector may be configured to provide an electrical connection to an electric detonation circuit. In a wireless detonation system, the connector may be a wireless receiving module that may participate in a wireless connection with a remote blast control unit. It is therefore contemplated that various types of initiation systems may be used to initiate the detonator 114 .

[0052] Throughout this specification, references to "an embodiment" or "the embodiment" mean that a particular feature, structure, or characteristic described in connection with that embodiment is included in at least one embodiment. Thus, phrases recited throughout this specification, or variations thereof, do not necessarily refer to the same embodiment.

[0053] Similarly, those skilled in the art having the benefit of this disclosure should appreciate that in the description of the above embodiments, various features may be grouped together in a single embodiment, drawing, or description thereof for the purpose of streamlining the disclosure. However, this method of disclosure should not be interpreted as reflecting an intention that any claim requires more features than are expressly recited in that claim. Rather, as the following claims reflect, some of the aspects of the invention reside in a combination of fewer than all features of a single embodiment as described above. Thus, the claims following this Detailed Description of the Invention are expressly incorporated into this Detailed Description of the Invention, with each claim standing on its own as a separate embodiment. This disclosure includes all permutations of the independent claims and their dependent claims.

Claims

1. 1. A system for pyrotechnic blast holes, comprising: Cap and a detonator subassembly including a detonator holder configured to fix a detonator in a pyrotechnic orientation, the detonator holder having an undeployed state and a deployed state; Equipped with The cap is a cap body having a top side, a bottom side, and a spool chamber disposed therein; an aperture through the bottom side centrally disposed with respect to the spool chamber; a hollow guide tube in axial alignment with and in communication with the aperture, the guide tube having an upper end fixed to the bottom side of the cap body and a lower end opposite the upper end; Equipped with In the undeployed state, the detonator holder is removably fixed to the lower end of the guide tube, and in the deployed state, the detonator holder is separated from the guide tube. system.

2. The detonator subassembly comprises: A detonator fixed to the detonator holder; a conductor having a detonator end connected to the detonator and a connector end opposite the detonator end; Equipped with the electrical conductor being substantially disposed within the spool chamber in the undeployed state; The system of claim 1 .

3. At least a portion of the conductor is wound within the spool chamber. The system of claim 2.

4. At least a portion of the wire is wound on a spool disposed within the spool chamber. The system of claim 2.

5. the spool chamber, in the deployed state, allows the conductor to unravel and be routed through the aperture and the guide tube. A system according to any one of claims 2 to 4.

6. the connector end including a connector configured to connect the conductor to a source of a detonation signal; A system according to any one of claims 2 to 5.

7. the connector comprises one of a wireless receiver module, a direct electrical connection, and a mechanical connection; The system of claim 6.

8. The conductor is one of a detonating cord, an electric wire, or a shock wave tube. A system according to any one of claims 2 to 7.

9. The cap body has a substantially circular shape. A system according to any one of claims 1 to 8.

10. the spool chamber including a hub surrounding the aperture; A system according to any one of claims 1 to 9.

11. The detonator holder is at least partially received within the lower end of the guide tube in the undeployed state. The system of claim 1 .

12. the detonator holder is frictionally secured within the lower end; The system of claim 11.

13. The detonator subassembly is configured to be coupled to an explosive delivery hose. A system according to any one of claims 1 to 12.

14. the spool chamber is open for access through the top side of the cap body; A system according to any one of claims 1 to 13.

15. the upper side of the cap body includes a removable lid; The system of claim 14.

16. the detonator holder further comprising a retention structure configured to maintain the detonator holder in a deployed position within the blasthole by interacting with a wall of the blasthole; 16. A system according to any one of claims 1 to 15.

17. the retention structure comprising one or more arms extending radially from the detonator holder for engaging a wall of the blast hole; 17. The system of claim 16.

18. the retention structure provides greater resistance to movement of the detonator holder in one direction within the blast hole versus movement in the opposite direction; 17. The system of claim 16.

19. the guide tube is sized to be received within the lip of a blast hole with a friction fit sufficient to secure the cap; 19. A system according to any one of claims 1 to 18.

20. The guide tube has an outer diameter of about 50 mm to about 300 mm.

20. A system according to any one of claims 1 to 19.

21. 1. A method for pyrotechnic blast holes, comprising: Providing a system according to any one of claims 2 to 20; placing the cap body on an edge of the blast hole opening such that the guide tube and detonator subassembly are directed into the blast hole; advancing an explosive delivery hose through said aperture and said guide tube to disengage said detonator holder and push said detonator subassembly into a deployed position in said blast hole; withdrawing the delivery hose from the deployed position and disconnecting the delivery hose from the detonator holder; A method comprising:

22. an explosive delivery hose is coupled to the detonator subassembly as it advances through the aperture; 22. The method of claim 21.

23. and discharging explosives through the delivery hose into the blast hole.

23. The method of claim 21 or 22.

24. the detonator subassembly disengages from the explosive delivery hose by releasing the explosive; 24. The method of claim 23.

25. and connecting the connector end to a source of a detonation signal.

25. The method of any one of claims 21 to 24.

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