Underwater excavation apparatus

Abstract

An excavation apparatus comprises a controlled flow underwater excavation apparatus. A housing thereof comprises at least one inlet and at least one outlet. The at least one inlet is provided on or at a side of the housing. A fluid flow path extends from the/each at least one inlet to the outlet. The fluid flow path comprises a first portion provided at or adjacent the/each at least one inlet. The first portion is included at a non-300 angle, e.g. is substantially perpendicular, to or converges towards a longitudinal axis of the housing and substantially straight. A second portion extends or continues from the first portion. A third portion extends or continues from the second portion. The third portion is substantially straight, contains at least part of a rotor, and is divergent away from the longitudinal axis of the housing in a flow direction from the inlet to the outlet.

Claims

1. An underwater excavation apparatus comprising: a housing having at least one inlet and an outlet, wherein the housing defines a fluid flow path from the at least one inlet to the outlet, and wherein the at least one inlet is provided on or at a side or sides of the housing; at least one rotor within the housing; and at least one stator within the housing; and wherein: the housing comprises a longitudinal axis, an inside of the housing converges from the at least one inlet towards the at least one rotor such that the fluid flow path converges towards the longitudinal axis, the inside of the housing diverges from an inlet end of the at least one rotor towards an outlet end of the at least one rotor such that the fluid flow path diverges from the longitudinal axis, and the inside of the housing converges from the at least one stator towards the outlet such that the fluid flow path converges towards the longitudinal axis.

2. An underwater excavation apparatus as claimed in claim 1, wherein one of: the at least one inlet is provided around the side or sides of the housing; the at least one inlet is provided circumferentially or peripherally around the side or sides of the housing.

3. An underwater excavation apparatus as claimed in claim 1, wherein at least one of: the at least one inlet is non-parallel to the longitudinal axis of the housing; the at least one inlet is inclined and/or offset from the longitudinal axis; the at least one inlet is transverse or substantially transverse to the longitudinal axis; the at least one inlet is perpendicular or substantially perpendicular to the longitudinal axis; the at least one inlet is provided at an angle to the outlet; the at least one inlet is provided at a non-zero (0 angle to the outlet; and/or the at least one inlet is perpendicular or substantially perpendicular to the outlet.

4. An underwater excavation apparatus as claimed in claim 1, wherein at least one of: the outlet is provided on or at an end of the housing; and/or the outlet is provided on or parallel to the longitudinal axis.

5. An underwater excavation apparatus as claimed in claim 1, wherein at least one of: the underwater excavation apparatus is adapted to provide a horizontal, substantially horizontal, non-vertical, or substantially non-vertical flow of fluid into the housing, in use; and/or the underwater excavation apparatus is adapted to provide a vertical, substantially vertical, non-horizontal or substantially non-horizontal flow of fluid out of or from the housing, in use.

6. An underwater excavation apparatus as claimed in claim 1, wherein the underwater excavation apparatus comprises a controlled flow underwater excavation apparatus.

7. An underwater excavation apparatus as claimed in claim 1, wherein the underwater excavation apparatus is adapted to provide and/or direct, in use, a flow of fluid/water at a pressure of 35 KPa to 125 KPa and/or a volume flow of 1 m.sup.3/s to 8 m.sup.3/s.

8. An underwater excavation apparatus as claimed in claim 1, wherein the underwater excavation apparatus comprises: a single rotor; and/or a single stator.

9. An underwater excavation apparatus as claimed in claim 1, wherein the fluid flow path comprises at least one of: a first section which extends from the at least one inlet; a second section which contains at least part of the at least one rotor, said second section diverging away from the longitudinal axis of the housing; a third section which contains at least part of the at least one stator, said third section converging towards the longitudinal axis of the housing; and/or a fourth section which extends towards the outlet.

10. An underwater excavation apparatus as claimed in claim 1, wherein the fluid flow path comprises: a first portion which is provided at or adjacent the at least one inlet, a second portion which extends or continues from the first portion, a third portion which extends or continues from the second portion, a fourth portion which extends or continues from the third portion, a fifth portion which extends or continues from the fourth portion, a sixth portion which extends or continues from the fifth portion, a seventh portion which extends or continues from the sixth portion.

11. An underwater excavation apparatus as claimed in claim 10, wherein at least one of: the first portion is convergent towards the longitudinal axis of the housing; the second portion is curved, bent, or arcuate; the second portion is convex relative to the longitudinal axis of the housing; the third portion is coincident with or contains at least part of the at least one rotor; the third portion is substantially straight; the third portion is divergent away from the longitudinal axis of the housing; the fourth portion is curved, bent, or arcuate the fourth portion is concave relative to the longitudinal axis of the housing; the fifth portion is substantially straight; the fifth portion is coincident with or contains at least part of the at least one stator; the fifth portion is convergent towards the longitudinal axis of the housing; the sixth portion is curved, bent, or arcuate; the sixth portion is convex relative to the longitudinal axis of the housing; the seventh portion is provided at or adjacent the outlet; the seventh portion is substantially vertical, in use; the seventh portion is parallel to the longitudinal axis of the housing; and/or the seventh portion is substantially straight.

12. An underwater excavation apparatus as claimed in claim 1, wherein at least one of: in an excavation mode, the outlet is configured to face an area to be excavated and the at least one inlet is provided above the outlet; and/or in a suction mode, the at least one inlet is configured to be proximal an area which has been excavated and/or requires to be cleared and the at least one inlet is provided below the outlet.

13. An underwater excavation apparatus as claimed in claim 1, wherein at least one of: the at least one rotor is provided proximal the at least one inlet; an apex of the at least one rotor faces the at least one inlet; the at least one stator is coaxial with the at least one rotor; the at least one stator is provided between the at least one rotor and the outlet.

14. An underwater excavation apparatus as claimed in claim 1, wherein the at least one rotor comprises a plurality of impeller blades.

15. An underwater excavation apparatus as claimed in claim 14, wherein the plurality of impeller blades comprises aerofoil blades.

16. An underwater excavation apparatus as claimed in claim 1, wherein the at least one rotor comprises a first body, wherein the first body comprises a first cone member, and wherein the plurality of impeller blades of the rotor are disposed on the first cone member.

17. An underwater excavation apparatus as claimed in claim 1, wherein the at least one stator comprises a plurality of vanes or blades.

18. An underwater excavation apparatus as claimed in claim 17, wherein the at least one stator comprises a second body, wherein the second body comprises a second cone member, and wherein the plurality of vanes or blades of the stator are disposed on the second cone member.

19. An underwater excavation apparatus as claimed in claim 17, wherein the at least one stator comprises: a plurality of primary stator blades; and a plurality of secondary or splitter blades between adjacent pairs of the primary stator blades.

20. An underwater excavation apparatus as claimed in claim 1, wherein the at least one rotor has a rotor rotation axis.

21. An underwater excavation apparatus as claimed in claim 20, wherein the rotor rotation axis comprises or is coincident with the longitudinal axis of the housing.

22. An underwater excavation apparatus as claimed in claim 20, wherein at least one of: the at least one rotor comprises a plurality of impeller blades, wherein the plurality of impeller blades are provided within the housing, such that, in use, flow of fluid past or across the at least one rotor is at the first angle from the rotor rotation axis, the first angle diverging away from the longitudinal axis in a direction away from the at least one inlet and towards the outlet; and in use, flow of fluid past or across the at least one stator is at the second angle from the rotor rotation axis, the second angle converging towards the longitudinal axis in the direction away from the at least one inlet and towards the outlet.

23. An underwater excavation apparatus as claimed in claim 22, wherein at least one of: the first angle is in the range of 45 to 65; the first angle is 55; the second angle is in the range of 55 to 75; the second angle is 65.

24. An underwater excavation system, device or tool, comprising at least one underwater excavation apparatus according to claim 1.

25. A method of underwater excavation, the method comprising: providing at least one underwater excavation apparatus according to claim 1; and excavating an underwater location using said underwater excavation apparatus.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) An embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings, which are:

(2) FIG. 1 a schematic sectional side view of an excavation apparatus, in use, said excavation apparatus according to a first embodiment of the present

(3) FIG. 2 a perspective view from one side and above of an excavation apparatus according to a second embodiment of the present invention;

(4) FIG. 3 a schematic sectional side view of the excavation apparatus of FIG. 2;

(5) FIG. 4 a schematic sectional side view of the excavation apparatus of FIG. 2, in use;

(6) FIG. 5 a schematic sectional view through like A-A of the excavation apparatus of FIG. 3; and

(7) FIG. 6 a schematic sectional side view of an alternative excavation apparatus according to a third embodiment of the present invention.

DETAILED DESCRIPTION OF DRAWINGS

(8) Referring initially to FIG. 1, there is shown an excavation apparatus comprising an underwater excavation apparatus, generally designated 5, according to a first embodiment of the present invention.

(9) The excavation apparatus 5 comprises a housing 20 comprising or having an inlet 25 and an outlet 30, wherein the inlet 25 is provided on or at an end (top end) of the housing 20.

(10) As can be seen from FIG. 1, the excavation apparatus 5 has a disadvantage, namely that when operated at or adjacent a fluid/water surface, e.g. in relatively shallow waters, a vortex 26 is produced at the inlet 25, in use. This may lead to the excavation apparatus 5 drawing or sucking air or an air/water mixture into the inlet 25.

(11) Referring now to FIGS. 2 to 5, there is shown an excavation apparatus comprising an underwater excavation apparatus, generally designated 105, according to a second embodiment of the present invention.

(12) The excavation apparatus 105 comprises a controlled flow excavation apparatus. The excavation apparatus 105 comprises a housing 120. The housing 120 comprises at least one inlet 125 and an outlet 130. The at least one inlet 125 is provided on or at a side or sides 126 of the housing 120.

(13) The at least one inlet 125 is/are provided around, e.g. circumferentially or peripherally around, a/the side 126 of the housing 120, e.g. adjacent an end of the housing. The housing 120 comprises a longitudinal axis A. The housing 120 is symmetrical with respect to the longitudinal axis A. The one or more inlets 125 is/are provided inclined or transversely or substantially transversely to the longitudinal axis A. The one or more inlets 125 is/are provided inclined or perpendicularly or substantially perpendicularly to the longitudinal axis A. The/each of the one or more inlets 125 is/are provided non-parallel to the longitudinal axis A of the housing 120.

(14) The/each of the one or more inlets 125 is/are provided at an angle, e.g. non zero (0) angle, e.g. perpendicularly or substantially perpendicularly, to the outlet 130. The outlet 130 is provided (centrally) on or at an end 131 of the housing 120.

(15) The excavation apparatus 105 is adapted to provide a horizontal or substantially horizontal or a non-vertical or substantially non-vertical flow of fluid/water into the housing 120, in use.

(16) The excavation apparatus 105 is adapted to provide a vertical or substantially vertical or a non-horizontal or substantially non-horizontal flow of fluid/water out of or from the housing 120, in use, e.g. in an excavation mode.

(17) The excavation apparatus 105 is adapted to provide and/or direct, in use, a flow of fluid/water, e.g. at a pressure of 35 KPa to 125 KPa and/or a volume flow of 1 m.sup.3/s to 8 m.sup.3/s.

(18) The underwater excavation apparatus 105 comprises at least one rotor 110, which is provided within the housing 120. The underwater excavation apparatus 105 comprises at least one stator 115, which is provided within the housing 120.

(19) There is provided a fluid flow path(s) F extending from the/each at least one inlet 125 to the outlet 130. The at least one rotor 110 and the at least one stator 115 are provided in the fluid flow path F.

(20) The fluid flow path F comprises a first (inlet) section, which extends from the at least one inlet 125.

(21) The/each fluid flow path F comprises a second (rotor) section, which contains at least part of rotor 110. Said second section diverges away from the longitudinal axis A of the housing 120.

(22) The fluid flow path F comprises a third (stator) section, which contains at least part of stator 115. Said third section converges towards a/the longitudinal axis A of the housing 120.

(23) The fluid flow path F comprises a fourth (outlet) section, which extends to the at least one or the outlet 130.

(24) The/each fluid flow path F comprises a first inlet/first portion F.sub.1 which is provided at or adjacent the/each at least one inlet 125. Said first portion F.sub.1 converges towards the axis A of the housing 120. Said first inlet portion or first portion F.sub.1 is advantageously substantially horizontal, in use, perpendicular to the axis A of the housing 120. In this embodiment the first portion F.sub.1 is substantially straight.

(25) The/each fluid flow path F comprises a second inlet portion or second portion F.sub.2 which extends or continues from the first portion F.sub.1. Said second portion F.sub.2 is advantageously curved, bent or arcuate, and convex relative to the longitudinal axis A of the housing 120.

(26) The/each fluid flow path F comprises a rotor portion or third portion F.sub.3 which extends or continues from the second portion F.sub.2. Said third portion F.sub.3 is advantageously substantially straight, coincident with or contains at least a part or parts of the rotor 110, and diverges away from the longitudinal axis A of the housing 120, in this embodiment in a flow direction from the inlet(s) 125 to the outlet 130, e.g. at an angle of 45 to 65, e.g. 55

(27) The/each fluid flow path F comprises a further/intermediate portion or fourth portion F.sub.4 which extends or continues from the third portion F.sub.3. Said fourth portion F.sub.4 is advantageously curved, bent or arcuate, and concave relative to the longitudinal axis A of the housing 120.

(28) The/each fluid flow path F comprises a stator portion or fifth portion F.sub.5 which extends or continues from the fourth portion F.sub.4. Said fifth portion F.sub.5 is advantageously substantially straight, coincident with or contains at least part or parts of the stator 115, and converges towards the longitudinal axis A of the housing 120, in this embodiment in a flow direction from the inlet 125 to the outlet 130, e.g. at an angle of 55 to 75, e.g. 65. Such arrangement is of benefit for excavation apparatus 105 adapted for use in relatively shallow waters, e.g. as such may allow for a relatively low profile/height excavation apparatus 105.

(29) The/each fluid flow path F comprises a sixth portion F.sub.6 which extends or continues from the fifth portion F.sub.5. Said sixth portion F.sub.6 is advantageously curved, bent or arcuate, and convex relative to the longitudinal axis A of the housing 120.

(30) The/each fluid flow path F comprises a first outlet portion or seventh portion F.sub.7 which extends or continues from the sixth portion F.sub.6. Said seventh portion F.sub.7 is provided at or adjacent the outlet 130. Said seventh portion F.sub.7 is advantageously substantially vertical, in use, parallel to the axis A of the housing 120, and substantially straight.

(31) The excavation apparatus 105 beneficially comprises a second outlet portion or single rotor 110. The excavation apparatus 105 beneficially comprises a single stator 115.

(32) In a first mode of operation, which comprises an excavation mode, the outlet 130 faces an area to be excavated and in such mode the inlet(s) 125 is/are provided above, e.g. directly above, the outlet 130.

(33) In a second mode of operation, which comprises a suction mode, the inlet(s) 125 is/are proximal an area which has been excavated and/or requires to be cleared, and in such mode the inlet(s) 125 is/are provided below the outlet, e.g. directly below the outlet.

(34) The rotor 110 and the stator 115 are provided in the housing 120. The housing 120 comprises axis A, the rotor 110 and the stator 115 being arranged coaxially upon the axis A. The rotor 110 is provided proximal the inlet(s) 125. The stator 115 is provided proximal the outlet 130.

(35) An inside of the housing 120 diverges from the at least one inlet 125 towards the rotor 110. The inside of the housing 120 converges from the stator 115 towards the outlet 130. The housing 120 is circumferentially/rotationally symmetrical about a/the axis A of the housing 120.

(36) The rotor 110 has a rotor rotation axis, which in this embodiment is axis A. The rotor 110 comprises a first body 139. The rotor 110 comprises a plurality of impeller blades 135 which are provided within the housing 120, such that, in use, flow of fluid passed or across the rotor 110 is, in use, at a first angle from the axis of rotation A.

(37) There are excavation and/or suction modes of the excavation apparatus 105. In excavation and/or suction mode, fluid flows from the at least one inlet 125 to the outlet 130 of the excavation apparatus 105.

(38) The rotor rotation axis A extends between a level of the at least one inlet 125 and the outlet 130. The first body 139 comprises a first cone member. The first angle diverges away from the axis A in a direction away from at least one of the at least one inlets 125 and towards the outlet 130. An apex of the first cone member faces the inlet 125.

(39) The plurality of impeller blades 135 comprises aerofoil blades, which are circumferentially disposed on a/the first cone member.

(40) The stator 115 is coaxial with the rotor 110 and the stator 115 is provided between the rotor 110 and the outlet 130. In use, flow of fluid passed or across the stator 115 is at a second angle from the axis of rotation of the rotor 110. The stator 115 comprises a second body 140, such as a second cone member. The second angle converges towards the axis A in a direction away from the inlet 125 and towards the outlet 130. An apex of the stator 115 faces the outlet 130. The stator 115 comprises a plurality of vanes or blades 145, such as aerofoil blades, which are disposed on a/the second cone member. The first angle is typically selected from either: in the range of 45 to 65, e.g. 55. The second angle is typically selected from in the range of 55 to 75, e.g. 65.

(41) The excavation apparatus 105 comprises means or an arrangement for dampening reactive torque on the excavation apparatus 105 caused by rotation of the rotor 110, in use. The excavation apparatus 105 and/or the at least one rotor 110 beneficially comprises a single rotor. The torque dampening means beneficially does not comprise a second rotor, such as a second rotor counter-rotating to the at least one (single) rotor. The excavation apparatus 105 beneficially comprises at least one stator 115, such as a single stator. The housing 120 comprises a hollow body.

(42) The rotor 110 and the stator 115 are provided in the housing 120. The housing 120 comprises axis A. The rotor 110 and the stator 115 are arranged coaxially, such as upon the axis A. The housing 120 is provided upon the axis A. The rotor 110 is provided proximal the at least one inlet 125, and/or the stator 115 is provided proximal the outlet 130.

(43) The rotor 110 comprises first body 139, such as a first cone body and the plurality of impeller blades 135, e.g. disposed on, such as circumferentially around, the first body 139.

(44) The stator 115 comprises second body 140, such as a second cone body, and a plurality of further blades 145, e.g. disposed on, such as circumferentially around, the second body 140.

(45) Further or stator blades 145 comprise one or more, e.g. a plurality of primary stator blades 146, and one or more, e.g. a plurality of, secondary or splitter blades 147 which are provided between adjacent pairs of primary stator blades 146. Such arrangement can be of benefit in excavation apparatus 105 adapted for use in relatively shallow waters, e.g. as such can allow relatively low profile/height excavation apparatus 105.

(46) The torque dampening means comprise or include anti-rotation vanes 148, e.g. at or proximal the outlet 130.

(47) As can be seen from FIG. 2, the excavation apparatus 105 also provides lifting points or lifting eyes 155, e.g. so as to allow suspension of the excavation apparatus 105 from a vessel (not shown) by one or more lines or wires (not shown). Also, at the inlets 125 there is/are provided a safety grill(s) 160, e.g. to mitigate ingress of solids at the inlet(s) 125. The excavation apparatus 105 also provides an attachment arrangement 165, e.g. for mounting of a frame, sonar, camera or the like. The excavation apparatus 105 also provides a drive motor 170 for driving the rotor 110, in use.

(48) The present invention further provides an excavation system device or tool, generally designated 205, such as an underwater excavation apparatus, device or tool comprising at least one excavation apparatus 105.

(49) The present invention further provides a method of excavation, such as a method of underwater excavation, the method comprising: providing at least one excavation apparatus 105; and excavating a location, such as an underwater location, using said excavation apparatus 105.

(50) Referring to FIG. 5, there is shown in more detail a cross-section of the excavation apparatus 105 taken along line A-A of FIG. 3. As can be seen in this embodiment there is provided four support members 175 which divides the inlet 25 into effectively four inlets. Around the inlet 25 is provided an inlet guard 180 which acts, e.g. to mitigate against ingress of unwanted materials into the inlet 25. Around the inlet 25 is provided a flange 105. On the longitudinal axis A is provided a bearing holder 190 and a bearings and drive shaft 195.

(51) Referring to FIG. 6, on the left hand side of the drawings there is shown a modified excavation apparatus, generally designated 105, according to a third embodiment of the present invention, parts of the excavation apparatus 105 being denoted with the same numerals as like parts of the excavation 105, but suffixed '.

(52) The excavation apparatus 105 differs from the excavation apparatus 105 in that the first (inlet) section of the fluid flow path F does not provide a first inlet portion or first portion F.sub.1, but rather comprises only second inlet portion or second inlet portion F.sub.2.

(53) For comparison purposes, in FIG. 6 the first (inlet) section arrangements of the excavation apparatus 105 and the excavation apparatus 105 are shown on the left hand side and right hand side of the figure, respectively.

(54) It will be appreciated that the embodiment of the present invention hereinbefore described is given by way of example only, and is not meant to be limiting of the invention in any way.

(55) It will be particularly appreciated that the arrangement of the at least one inlet is adapted and/or designed to provide and/or encourage fluid flow ingress from a side or sides rather than an end/top of the housing. This is of particular benefit when operating at or near a surface of a body of fluid/water and/or in relatively shallow depths, e.g. so as to reduce any vortex effects at the inlet. Another key feature of such an excavation apparatus, particularly for such use, is a relatively large stator path converging angle relative to the longitudinal axis A, as such reduces the required height of the housing. To achieve the shorter, low profile, housing height, the provision of the secondary/splitter blades is of particular benefit.