A delivery system for mixing and dispensing a gel stemming material into a blast hole is disclosed. The system includes a dual-pump assembly in fluid communication with respective sources of a first gel precursor fluid and a second gel precursor fluid; a pair of hoses associated with a means to vary an effective length of said hoses; a dosing head having a first inlet and a second inlet, said inlets arranged in respective fluid communication via said hoses with the dual pump assembly to receive the first and second gel precursor fluids, the dosing head being configured to receive and mix the first and second gel precursor fluids to produce the gel stemming material and to dispense the gel stemming material via an outlet. In use, the effective length of the hoses may be varied to position the dosing head and dispense the gel stemming material in the blast hole.

A delivery system for mixing and dispensing a gel stemming material into a blast hole is disclosed. The system includes a dual-pump assembly in fluid communication with respective sources of a first gel precursor fluid and a second gel precursor fluid; a pair of hoses associated with a means to vary an effective length of said hoses; a dosing head having a first inlet and a second inlet, said inlets arranged in respective fluid communication via said hoses with the dual pump assembly to receive the first and second gel precursor fluids, the dosing head being configured to receive and mix the first and second gel precursor fluids to produce the gel stemming material and to dispense the gel stemming material via an outlet. In use, the effective length of the hoses may be varied to position the dosing head and dispense the gel stemming material in the blast hole.

In a seal device for a hydraulic circuit, in which an oil passage that supplies hydraulic oil to or discharges the hydraulic oil from a hydraulic actuator operated by hydraulic pressure is formed over at least two members that relatively move, and a seal member that seals a gap between the two members in a liquid-tight manner is disposed in an interior of a groove section that is formed in at least either one of the two members, a communication section that allows the groove section to communicate with any portion of the oil passage such that the hydraulic oil in the interior of the groove section moves along with supply of the hydraulic oil to or discharge of the hydraulic oil from the hydraulic actuator is formed.

An apparatus and method for filling boreholes with dry mass such sand, gravel, concrete and dry mortars or other similar materials from a deposit or a truck in blasting operations. The apparatus includes a container for storage of mass, conveying device with a conveyor screw for conveying the mass from the container into a hose and a compressed air supply for directing flow of the mass in the hose towards a dispenser. The compressor air supply is adapted to forcibly urge the mass into boreholes. The dispenser is adapted for positioning over the boreholes for filling with mass before blasting operations.

An apparatus and method for filling boreholes with dry mass such sand, gravel, concrete and dry mortars or other similar materials from a deposit or a truck in blasting operations. The apparatus includes a container for storage of mass, conveying device with a conveyor screw for conveying the mass from the container into a hose and a compressed air supply for directing flow of the mass in the hose towards a dispenser. The compressor air supply is adapted to forcibly urge the mass into boreholes. The dispenser is adapted for positioning over the boreholes for filling with mass before blasting operations.

An apparatus and method for filling boreholes with dry mass such sand, gravel, concrete and dry mortars or other similar materials from a deposit or a truck in blasting operations. The apparatus includes a container for storage of mass, conveying device with a conveyor screw for conveying the mass from the container into a hose and a compressed air supply for directing flow of the mass in the hose towards a dispenser. The compressor air supply is adapted to forcibly urge the mass into boreholes. The dispenser is adapted for positioning over the boreholes for filling with mass before blasting operations.

In one preferred form of the present invention there is provided a method of stemming a blast hole with a super absorbent polymer. The method includes providing a super absorbent polymer substance as a gelled length in the blast hole. The gelled length provides a pressure wave reflecting stem, to increase the efficiency of an explosive during blasting, with the explosive being located in the blast hole.

In one preferred form of the present invention there is provided a method of stemming a blast hole with a super absorbent polymer. The method includes providing a super absorbent polymer substance as a gelled length in the blast hole. The gelled length provides a pressure wave reflecting stem, to increase the efficiency of an explosive during blasting, with the explosive being located in the blast hole.

An apparatus, method and insulation medium for inserting and insulating a charge medium within a borehole includes a charge tube comprised of an elongate tube having a length and diameter sufficient for containing a desired quantity of a charge medium. A charge medium in a pumpable form is provided for substantially filling the charge tube. An insulation medium in a pumpable form is provided for substantially encapsulating the charge tube and substantially filling an annular space between the charge tube and the borehole for insulating the charge tube from a downhole environment in which the charge tube is to be inserted. A detonator is inserted within the charge medium proximate a distal end of the charge tube and a charge cable extends from the detonator through the charge tube and exits from the charge tube.

An apparatus, method and insulation medium for inserting and insulating a charge medium within a borehole includes a charge tube comprised of an elongate tube having a length and diameter sufficient for containing a desired quantity of a charge medium. A charge medium in a pumpable form is provided for substantially filling the charge tube. An insulation medium in a pumpable form is provided for substantially encapsulating the charge tube and substantially filling an annular space between the charge tube and the borehole for insulating the charge tube from a downhole environment in which the charge tube is to be inserted. A detonator is inserted within the charge medium proximate a distal end of the charge tube and a charge cable extends from the detonator through the charge tube and exits from the charge tube.