| 摘要 |
<p>An apparatus for cleaning calcites and other extraneous matter from the perforated casing of a sub-terrainian water well comprises a plurality of elongate explosive members (14) for lowering into the well, detonators (16) for detonating each member (14) to produce an explosion which propagates longitudinally of the well, and a plurality of short tubular attenuators (19) circumscribing the explosive members (14)at intervals along the length thereof. Each tubular attenuator (19) comprises a steel tube (20) and an annular ring (21) extending around the tube at a point along the length thereof. The tensile strength of the tube (20) is arranged to be less than that of the force produced by the explosion, whereas the tensile strength of the rings (21) is arranged to be greater than that of the force produced by the explosion. The ring (21) thus serve to attenuate the pressure wave substantially more than tubes (20), thereby helping to produce a more pronounced attenuation. Furthermore, the shape and direction of the pressure wave of the explosion can be altered according to the relative positioning of the ring (21) on the tubes (20).</p> |
