| 摘要 |
ICIA 1384/13 "Conduit Constriction Means" A means for the constriction of fluid movement in a conduit comprises a tubular wall-gripping member which is freely movable within the conduit but which is capable of lateral expansion to grip the conduit wall. The wall-gripping member has an exterior (wall-gripping) surface and an interior surface which is so shaped that, when the wall-gripping member is prevented from moving in the conduit, the action of the fluid, either directly or indirectly, on the interior surface causes expansion. In a preferred embodiment, a tube is segmented into four segments which are secured by circumferential elastic bands. The interior surface is frusto-conical and the action of fluid on a similarly-shaped frusto-conical vessel placed therein causes expansion. The means is particularly useful in the explosives industry for providing "air-decking" in vertical blast holes. |
