| 摘要 |
<p>: Cartridge end-closure A tubular explosives cartridge having at least one end closed by a transverse closure disc of resilient closed-cell foamed synthetics plastics material, for example, foamed polyethylene, the disc having an uncompressed diameter greater than the internal diameter of the tubular cartridge case. The closure provides a waterproof seal without preventing communication of detonation between cartridges and may be readily pierced for the insertion of a detonator. When the closure consists of nitrogen blown polyethylene, it does not increase the risk of firedamp ignition in coal mines.</p> |
