Base charge explosive system application

Abstract

A detonator which includes a tubular housing with a bore in which is formed a compartment that houses a first frangible container with a first quantity of a first material inside the first container, a second frangible container with a second quantity of a second material inside the second container, and an actuating mechanism which is operable to break the first container and the second container thereby to allow the first material to contact the second material and form an explosive composition inside the compartment.

1 - 11 . (canceled) 
     
     
         12 . A detonator ( 30 ) which includes a tubular housing ( 32 ) with a bore ( 36 ) in which is formed a compartment ( 42 ), a first frangible container ( 44 ) inside the compartment ( 42 ), a first quantity of a first material (A) inside the first container ( 44 ), a second frangible container ( 46 ) inside the compartment ( 42 ), a second quantity of a second material (B) inside the second container ( 46 ), and an actuating mechanism ( 34 ) which is operable to break the first container ( 44 ) and the second container ( 46 ) thereby to allow the first material (A) to contact the second material (B) and form an explosive composition inside the compartment ( 42 ) characterised in that the housing ( 32 ) has a mouth ( 38 ), to the bore ( 36 ), which is connectable to an initiating source ( 104 ) in that inside the bore ( 36 ), a time delay composition ( 48 ) is exposed to the mouth ( 38 ), and a primary explosive ( 90 ) is located between the time delay composition ( 98 ) and said compartment ( 42 ), in that a safety device ( 80 ) is provided to prevent inadvertent breaking of the first container ( 44 ) and of the second container ( 46 ) and in that the explosive composition is formed in a period which is not less than one minute after the first material (A) contacts the second material (B). 
     
     
         13 . A detonator according to  claim 12  wherein the actuating mechanism ( 34 ) includes a tool ( 70 ,  72 ,  76 ) which is movable by a user to break the first container ( 44 ) and the second container ( 44 ) and to cause mixing of the first material (A) with the second material (B). 
     
     
         14 . A detonator according to  claim 13  wherein the safety device ( 80 ) is in the form of a retention member ( 82 ) which is engaged with the housing ( 32 ) and with the tool thereby to restrict movement of the tool ( 70 ,  72 ,  76 ) relative to the housing ( 32 ), and wherein the retention member is disengageable from at least one of the housing ( 32 ) and the tool ( 70 ,  72 ,  76 ) thereby to allow movement of the tool relative to the housing. 
     
     
         15 . A detonator according to  claim 14  wherein the tool ( 70 ,  72 ,  76 ) includes an inner end ( 72 ) positioned in the compartment, an outer end ( 78 ) which is positioned outside of the housing ( 32 ), and a link ( 76 ) which extends through a wall ( 40 ) of the housing ( 32 ) and which connects the inner end ( 72 ) to the outer end ( 78 ), wherein the outer end ( 78 ) is engageable by a user thereby to cause movement of the inner end ( 72 ) to break the first container ( 44 ) and the second container ( 46 ). 
     
     
         16 . A detonator according to  claim 15  wherein the tool ( 70 ,  72 ,  76 ) is movable linearly relative to the housing ( 32 ) and wherein the tool and the housing include interengageable formations ( 110 ) which cause at least part of the tool to rotate relative to the housing upon said linear movement. 
     
     
         17 . A detonator according to  claim 12  wherein the actuating mechanism ( 34 ) comprises at least a portion ( 32 A) of the housing which is deformable to cause the containers ( 44 ,  46 ) to be broken. 
     
     
         18 . A detonator according to  claim 17  which includes a removable rigid sleeve ( 100 ) around the deformable portion ( 32 A) of the housing. 
     
     
         19 . A detonator according to  claim 18  wherein the first material (A) is pentaerythritol and the second material (B) is nitric acid. 
     
     
         20 . A detonator according to  claim 12  wherein the safety device ( 80 ) is in the form of a retention member ( 82 ) which is engaged with the housing ( 32 ) and with the tool thereby to restrict movement of the tool ( 70 ,  72 ,  76 ) relative to the housing ( 32 ), and wherein the retention member is disengageable from at least one of the housing ( 32 ) and the tool ( 70 ,  72 ,  76 ) thereby to allow movement of the tool relative to the housing. 
     
     
         21 . A detonator according to  claim 20  wherein the tool ( 70 ,  72 ,  76 ) includes an inner end ( 72 ) positioned in the compartment, an outer end ( 78 ) which is positioned outside of the housing ( 32 ), and a link ( 76 ) which extends through a wall ( 40 ) of the housing ( 32 ) and which connects the inner end ( 72 ) to the outer end ( 78 ), wherein the outer end ( 78 ) is engageable by a user thereby to cause movement of the inner end ( 72 ) to break the first container ( 44 ) and the second container ( 46 ). 
     
     
         22 . A detonator according to  claim 21  wherein the tool ( 70 ,  72 ,  76 ) is movable linearly relative to the housing ( 32 ) and wherein the tool and the housing include interengageable formations ( 110 ) which cause at least part of the tool to rotate relative to the housing upon said linear movement.