| 摘要 |
1,084,942. Blasting cartridges. DYNAMIT NOBEL A.G. Jan. 11, 1965 [Jan. 11, 1964], No. 1271/65. Heading F3A. Apparatus by means of which a borehole is saturated with water, before firing a blasting charge housed within the apparatus, comprises a water ejection means 1 and a blasting cartridge 2 connected together by a member 3. The ejection means 1 can be connected by a union 5 and a nipple 4 to a pressure water supply and comprises a pipe 6 connected to one end of an expansible hose 8 which is connected at its other end to a discharge head 10 having peripheral openings 11. The connection 3 comprises a block 12 with an axial bore 13 leading to a recess housing an electric fuze 28 adjacent the base 19 of the cartridge 2. Base 19 is held to the block 12 by a sleeve 15 and is axially bored to receive a priming charge 29 in communication with a flash tube 24 extending through the main charge 27 (nitrocellulose powder) in a casing 21. Casing 21, which may be integral with the base 19, is made of polyethylene and the tube 24 is made of cardboard. A metal sleeve (not shown) may line the bore for the primer 29 and the casing 21 may be in two or more sections, one section being filled with part of the charge 27 before connection of the next section. When the charge is thus formed, each filled section is closed by a disc before connecting the next section, the disc having a flanged aperture to receive the tube 24. A bayonet connection 18, 20 between the sleeve 15 and base 19 allows storage of the apparatus separately from the fuze, which may be inserted immediately before use and the cartridge 2 may be connected at the last moment to the water-ejection means 1. On insertion in a borehole a gauge is used to check the water pressure built up therein, before manually closing the circuit to the fuze 28. Alternatively a pressure-dependant switch may be used to close the circuit. |
