Abstract: An underwater excavation apparatus having various mechanisms for moving the underwater excavation apparatus that are provided on or adjacent to the apparatus is described. The mechanisms for moving the underwater excavation apparatus provide for orienting, positioning, rotating, counteracting reactive torque and/or steering the apparatus.

Abstract: Underwater power generator or turbine unit (2; 102; 202; 302; 402) comprises a first housing part (4; 104; 204; 304P, a second body part (6; 106, 206, 306, 406) and means for connecting the first and second housing parts (4, 6; 104, 106; 204, 206; 304, 306; 404; 406). The connecting means (8; 108; 208; 308) comprise a plurality of bars (22; 122; 222; 322). The generator (2; 102; 202; 302) comprises a base (28; 128; 228; 328), having three logs (30, 32, 130, 132, 134; 230, 232,234;330, 332, 334; 430, 432, 434). The generator (2; 102; 202; 302, 402) and flow channel (44; 104; 204, 304) having first and second ends, the legs (30, 32,34; 130, 132, 134; 230, 232, 234, -330, 332, 334; 430, 432, 434) having provided longitudinally outwardly of the ends and/or transversely outwardly of sides of the flow channel (44; 104; 204; 304).

Abstract: An underwater excavation apparatus having means for moving the underwater excavation apparatus that are provided on or adjacent to the apparatus. The means for moving the underwater excavation apparatus provide for orienting, positioning, rotating, counteracting reactive torque and/or steering the apparatus. The apparatus has a pair of horizontally opposed or symmetrically disposed inlets communicating with a single outlet that is disposed vertically downwards.

Abstract: There is disclosed an improved bearing and particularly an improved bearing assembly (15, 15A), eg. a thrust bearing assembly, which may be used in down-hole applications, such as down-hole drilling applications. Thrust bearing assemblies for use in down-hole applications have the conflicting requirements of a thick shaft assembly and high axial load bearing capacity in a small cross-section. The invention, therefore, provides: a bearing assembly (15, 15A) having at least two bearing elements (400, 400A) spaced by a first body (500, 500A), the first body (500, 500A) having means for flexing. Thus when a load is applied to the bearing assembly (15, 15A) the first body (500, 500A) is caused to flex. In an embodiment the flexing means comprise at least one circumferential groove or notch (510, 510A) formed on the first body (500, 500A).

Abstract: The present invention provides a self-contained propulsion apparatus 1 suitable for a sub-sea ROV. The apparatus comprises: a reactor vessel 2 having at least one inlet 3, 4 and an exhaust 7; reservoirs 10, 11 for holding fuel and an oxidant material therefor, wherein the reaction products of said fuel and oxidant comprise steam; a remotely operable fuel and oxidant supply control device 12, 13; and a steam turbine 9 connected to the exhaust 7 so as to be driven by steam from the reactor vessel 2. The turbine 9 is drivingly connected 39 to a propulsion device 42 for propelling the ROV in use thereof. A degassing apparatus 17 is provided for substantially removing steam and any other gas phase reaction products, from the gas phase into the liquid and/or solid phase, downstream of the turbine 9.

Abstract: The present invention provides a down-hole tool (7) with at least one radially outwardly deployable tool element (33) for use in a bottom hole assembly (1) provided with a pressurised down-hole motor drive fluid supply (50). The tool (7) comprises a body (9) having at least one tool element (33) having a mounting, proximal, end portion (32) pivotally mounted (31) on said body, and a working, distal, end portion (34) displaceable between a stowed, radially inward, position and a deployed, radially outward, position. The proximal end portion (32) is provided with an engagement portion (29, 30) formed and arranged for driven engagement with a drive member (23) axially displaceable by a piston and cylinder device (19, 20). In use of the tool (7), axial displacement of the drive member (23) causes said proximal end portion (32) to rotate and displace said tool element working end portion (34) between said stowed and deployed positions thereof.

Abstract: An improved underwater excavation apparatus achieves efficiency and control of movement through provision of a hollow body having at least one inlet and at least one outlet, at least one pair of impellers coaxially displaced one from the other and rotatably mounted in the hollow body, and a mechanism for driving the impellers in contrary rotating directions. The underwater excavation apparatus comprises a pair of horizontally opposed inlets communicating with a single outlet, the outlet being disposed vertically downwards substantially midway between the two inlets, in use. The excavation apparatus may, therefore, be substantially “T” or “Y” shaped. The mechanism for driving the impellers may include at least one drilling motor.