| 摘要 |
<p>An inflatable bag assembly comprises first and second containers, each holding a reagent. The containers are secured inside a flexible gas-tight bag in a spaced apart relationship. Preferably, a tough outer bag surrounds the gas-tight bag. Several securing members such as elastic bands hold the assembly in a folded configuration in which the containers are separated by at least one fold in the gas-tight bag. An attachment element is provided for connecting the inflatable bag assembly to a support or actuator member, such as a line by which the assembly is lowered down a borehole in use, or an associated actuator rod. The reagents typically comprise an acid and a base which, when mixed, react to release an inflating gas. For example, the acid may be citric acid and the base may be sodium bicarbonate in liquid form. The reagent containers are preferably sachets of flexible plastics material which is sufficiently strong to prevent leakage of the sachets during handling of the inflatable bag assembly, but sufficiently weak to be breakable in use by the application of localised force by a user. The inflatable bag assembly is actuated, after breakage of the sachets and lowering of the folded assembly into a borehole, by jerking the folded assembly hard enough to cause it to unfold partially and allow the reagents to mix.</p> |
