| 摘要 |
There is disclosed an improved underwater excavation apparatus (300a, b, c). Known apparatus suffer from a number of problems, e.g., efficiency and control of movement. Accordingly, the invention provides an underwater excavation apparatus (300a, b, c) comprising a hollow body (370a, b, c) having at least one inlet (371a, b, c) and at least one outlet (373a, b, c), at least one pair of impellers (335a, b, c), (340a, b, c) coaxially displaced one from the other and rotatably mounted in the hollow body (370a, b, c), and means for driving the impellers in contrary rotating directions. The underwater excavation apparatus (300a, b, c) comprises a pair of horinzontally opposed inlets (371a, b, c) communicating with a single outlet (373a, b, c) the outlet (373a, b, c) being disposed vertically downwards substantially midway between the two inlets, in use. The excavation apparatus (300a, b, c) may, therefore, be substantially "T" or "Y" shaped. The means for driving the impellers (335a, b, c), (340a, b, c) may include at least one drilling motor (310a, b, c). |
