Patents Assigned to Rotech Holdings Limited
  • Patent number: 8522460
    Abstract: The present invention relates to an underwater excavation apparatus. The apparatus of the invention utilizes mass flow for disturbing or excavating an underwater location and for extracting or sucking excavated material from the underwater location to another location. Restriction of spoil and/or direct spoil is provided for the apparatus and comprises a baffle provided within a cavity of a housing having an open base for the extracting or sucking of excavated material. An outlet for disturbing or excavating and an inlet for extraction or suction are located within the housing while an inlet for disturbing or excavating and an outlet for extraction or suction are located external to the housing.
    Type: Grant
    Filed: April 30, 2009
    Date of Patent: September 3, 2013
    Assignee: Rotech Holdings Limited
    Inventor: Donald Stewart
  • Patent number: 8115329
    Abstract: Known underwater turbine units suffer from problems, e.g. an ability to operate in ebb and/or flow tides. Accordingly, the invention provides aerofoil (5), wherein the aerofoil (5) is symmetrical about a mid-chord line (A) thereof. The aerofoil (5) may be symmetrical about a chord (B) thereof. The underwater turbine unit (3) comprises at least one turbine (25) which comprises at least one blade (20) which comprises the aerofoil (5).
    Type: Grant
    Filed: May 18, 2006
    Date of Patent: February 14, 2012
    Assignee: Rotech Holdings Limited
    Inventor: David Stuart Thompson
  • Patent number: 7944073
    Abstract: A power generator includes at least one underwater turbine unit providing a housing having a flow channel therethrough and at least one turbine means mounted in the flow channel for rotation in response to water flow through the flow channel. The turbine unit provides a turbine unit part releasably mountable in the turbine unit. The turbine unit part includes at least one of the at least one turbine means and a pump means. The turbine unit part is releasably mountable through an aperture in a side wall of the housing.
    Type: Grant
    Filed: February 11, 2008
    Date of Patent: May 17, 2011
    Assignee: Rotech Holdings Limited
    Inventors: Hector Fillipus Alexander Van Drentham Susman, Kenneth Roderick Stewart, Donald Stewart
  • Publication number: 20110056098
    Abstract: There is disclosed an underwater excavation apparatus (5) comprising: means (10) for disturbing or excavating an underwater location, comprising mass flow excavation means (20); and means (15) for extracting or sucking excavated material from the location to another location comprising further mass flow means (25). Means (30) to restrict spoil and/or direct spoil to the suction means (25) are provided and comprises a baffle (35) provided within a cavity (45) of a housing (40) having an open base (60). An outlet (105) of the mass flow means (20) and an inlet (110) of the suction means (25) are located within the housing (40), while an inlet (100) of the mass flow means (20) and an outlet (115) of the suction means (25) are located external of the housing (40).
    Type: Application
    Filed: April 30, 2009
    Publication date: March 10, 2011
    Applicant: ROTECH HOLDINGS LIMITED
    Inventor: Donald Stewart
  • Patent number: 7768145
    Abstract: A power generator includes at least one underwater turbine unit providing a housing having a flow channel therethrough and at least one turbine means mounted in the flow channel for rotation in response to water flow through the flow channel. The turbine unit provides a turbine unit part releasably mountable in the turbine unit. The turbine unit part includes at least one of the at least one turbine means and a pump means. The turbine unit part is releasably mountable through an aperture in a side wall of the housing.
    Type: Grant
    Filed: October 4, 2002
    Date of Patent: August 3, 2010
    Assignee: Rotech Holdings Limited
    Inventors: Hector Fillipus Alexander Van Drentham Susman, Kenneth Roderick Stewart, Donald Stewart
  • Patent number: 7686075
    Abstract: The present invention relates to a downhole tool. In particular, the present invention relates to a downhole pump assembly, a downhole tool assembly including a downhole pump assembly, a well including a downhole pump assembly and to a method of recovering well fluids. In one embodiment of the invention, there is disclosed a downhole tool assembly (10) for location in a borehole (16) of a well (12), the tool assembly (10) including a downhole pump assembly (18). The pump assembly (18) comprises a turbine (26) coupled to a pump (28), for driving the pump (28) to recover well fluid.
    Type: Grant
    Filed: November 25, 2002
    Date of Patent: March 30, 2010
    Assignee: Rotech Holdings Limited
    Inventors: Kenneth Roderick Stewart, Hector Fillipus Alexander Van Drentham Susman
  • Publication number: 20100043256
    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.
    Type: Application
    Filed: November 26, 2007
    Publication date: February 25, 2010
    Applicant: ROTECH HOLDINGS LIMITED
    Inventors: Hector Filippus Alexander Van Drentham Susman, Kenneth Roderick Stewart
  • Patent number: 7073610
    Abstract: A downhole tool for generating a longitudinal mechanical load. In one embodiment, a downhole hammer is disclosed which is activated by applying a load on the hammer and supplying pressurizing fluid to the hammer. The hammer includes a shuttle valve and piston that are moveable between first and further position, seal faces of the shuttle valve and piston being released when the valve and the piston are in their respective further positions, to allow fluid flow through the tool. When the seal is releasing, the piston impacts a remainder of the tool to generate mechanical load. The mechanical load is cyclical by repeated movements of the shuttle valve and piston.
    Type: Grant
    Filed: November 18, 2003
    Date of Patent: July 11, 2006
    Assignee: Rotech Holdings Limited
    Inventor: Hector Fillipus Alexander Van Drentham Susman
  • Patent number: 6854953
    Abstract: The present invention provides a speed governor (5) suitable for use in a fluid driven down-hole tool (3). The speed governor comprises an actuator (7) operatively coupled to a motive fluid flow control valve (6). The actuator is and arranged so as to be activatable, directly or indirectly, in response to the running speed of the tool (3), for opening of the control valve (6) with increasing rotational speed of the motor (3) above a predetermined speed limit thereby to limit the rotational speed of the downhole tool (3).
    Type: Grant
    Filed: August 5, 2002
    Date of Patent: February 15, 2005
    Assignee: Rotech Holdings, Limited
    Inventors: Hector F. A. Van Drentham-Susman, Kenneth Roderick Stewart, Richard D. Neilson, Donald Stewart, Gary L. Harris
  • Patent number: 6837759
    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.
    Type: Grant
    Filed: September 6, 2001
    Date of Patent: January 4, 2005
    Assignee: Rotech Holding Limited
    Inventor: Hector Filippus Alexander Van-Drentham Susman
  • Patent number: 6581690
    Abstract: The present invention provides an active downhole cutting tool guide device 14 for use in a hole 17 with sides between which a hole-cutting tool 15 mounted on a drill string and provided with said device may be disposed. The guide device 14 comprises at least one elongate longitudinally extending hole-side engagement member 20 mounted on a body 19 disposable, in use of the device, in-line with the drill string, so as to be movable relative to said body 19 between a retracted position and a radially outwardly displaced position for hole-side engagement. Each engagement member 20 has pressurized-fluid operable actuator mechanism 24 formed and arranged for driving said hole-side engagement member 20 between its retracted and hole-side engagement positions. The guide device 14 includes pressurized fluid supply mechanism 28, 18 formed and arranged for controlling the supply of pressurized fluid to the actuator mechanism 24, for operation thereof.
    Type: Grant
    Filed: October 30, 2001
    Date of Patent: June 24, 2003
    Assignee: Rotech Holdings, Limited
    Inventors: Hector F. A. Van Drentham-Susman, Kenneth Roderick Stewart
  • Patent number: 6527513
    Abstract: A turbine (4) suitable for use in down-hole drilling and the like, and comprising a tubular casing (11) enclosing a chamber (18) having rotatably mounted therein a rotor (19). The rotor (19) comprises at least one turbine wheel blade arrays (30a) with an annular array of angularly distributed blades (30), and a generally axially extending inner drive fluid passage (14) generally radially inwardly of said rotor (19). The casing (11) also has respective generally axially extending outer drive fluid passage (16) associated with said at least one turbine wheel blade array (30a), and one of the inner and the outer drive fluid passages (14, 16) constitute a drive fluid supply passage and is provided with outlet nozzles (17) formed and arranged for directing at least one jet of drive fluid onto the blade drive fluid receiving faces (31) for imparting rotary drive to said rotor (19).
    Type: Grant
    Filed: January 31, 2001
    Date of Patent: March 4, 2003
    Assignee: Rotech Holdings Limited
    Inventors: Hector F.A. Van Drentham-Susman, Kenneth Roderick Stewart
  • Patent number: 6430848
    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.
    Type: Grant
    Filed: August 12, 1999
    Date of Patent: August 13, 2002
    Assignee: Rotech Holdings Limited
    Inventors: Hector Filippus Alexander Van Drentham Susman, Kenneth Roderick Stewart
  • Patent number: 6178670
    Abstract: There is provided an improved apparatus for recovery of sea-bed material. Known apparatus suffer from problems such as low recovery rate and capital cost. The invention, therefore, provides a recovery apparatus comprising a vehicle upon which are mounted a duct permitting communication between the sea-bed and a location remote therefrom, structure to introduce sea-bed material into the duct and structure to advance sea-bed material through the duct.
    Type: Grant
    Filed: January 8, 1999
    Date of Patent: January 30, 2001
    Assignee: Rotech Holdings Limited
    Inventors: Hector Fillipus Alexander Van Drentham Susman, Kenneth Roderick Stewart