EP0047803A1 - Procédé et dispositif à drague suceuse pour aspirer des matières draguées - Google Patents

Procédé et dispositif à drague suceuse pour aspirer des matières draguées Download PDF

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Publication number
EP0047803A1
EP0047803A1 EP80200862A EP80200862A EP0047803A1 EP 0047803 A1 EP0047803 A1 EP 0047803A1 EP 80200862 A EP80200862 A EP 80200862A EP 80200862 A EP80200862 A EP 80200862A EP 0047803 A1 EP0047803 A1 EP 0047803A1
Authority
EP
European Patent Office
Prior art keywords
suction
head
dredgings
head wall
flexible
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
EP80200862A
Other languages
German (de)
English (en)
Inventor
Adriaan Daniel Bakker
Tjako Aaldrik Wolters
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Dosbouw VoF
Original Assignee
Dosbouw VoF
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Dosbouw VoF filed Critical Dosbouw VoF
Priority to EP80200862A priority Critical patent/EP0047803A1/fr
Publication of EP0047803A1 publication Critical patent/EP0047803A1/fr
Ceased legal-status Critical Current

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Classifications

    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F3/00—Dredgers; Soil-shifting machines
    • E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
    • E02F3/88—Dredgers; Soil-shifting machines mechanically-driven with arrangements acting by a sucking or forcing effect, e.g. suction dredgers
    • E02F3/90—Component parts, e.g. arrangement or adaptation of pumps
    • E02F3/92—Digging elements, e.g. suction heads
    • E02F3/9243—Passive suction heads with no mechanical cutting means
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F3/00—Dredgers; Soil-shifting machines
    • E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
    • E02F3/88—Dredgers; Soil-shifting machines mechanically-driven with arrangements acting by a sucking or forcing effect, e.g. suction dredgers
    • E02F3/90—Component parts, e.g. arrangement or adaptation of pumps
    • E02F3/907—Measuring or control devices, e.g. control units, detection means or sensors
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F3/00—Dredgers; Soil-shifting machines
    • E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
    • E02F3/88—Dredgers; Soil-shifting machines mechanically-driven with arrangements acting by a sucking or forcing effect, e.g. suction dredgers
    • E02F3/90—Component parts, e.g. arrangement or adaptation of pumps
    • E02F3/92—Digging elements, e.g. suction heads
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F3/00—Dredgers; Soil-shifting machines
    • E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
    • E02F3/88—Dredgers; Soil-shifting machines mechanically-driven with arrangements acting by a sucking or forcing effect, e.g. suction dredgers
    • E02F3/90—Component parts, e.g. arrangement or adaptation of pumps
    • E02F3/92—Digging elements, e.g. suction heads
    • E02F3/9293—Component parts of suction heads, e.g. edges, strainers for preventing the entry of stones or the like

Definitions

  • the invention relates to a method of sucking up dredgings from subaqueous ground, wherein a suspension stream of dredgings and water is sucked up by means of a suction head and a dredgings transport conduit connected with the former and provided with pump means and wherein at least one suction-head lower rim connected by means of at least one flexible suction-head wall with the dredgings transport conduit is held at a level matchig the ground level.
  • the invention provides a method of readily lifting dredgings and/or material to be eroded by a water stream from the ground and has for its object to reduce in-flow losses.
  • the method according to the invention is characterized in that the shape of the flexible suction-head wall is adjusted in dependence on a pressure difference between the pressure of the suspension stream locally flowing along the flexible suction-head wall and the pressure prevailing on the side of the flexible suction-head wall remote from the suspension stream.
  • a further developed method is characterized in that the flexible suction-head wall is adjusted with respect to the bottom by setting the level of a frame carrying the flexible suction-head wall with respect to the dredgings transport conduit.
  • a further developed method is characterized in that a flow profile of the flexible suction-head wall is adjusted by fastening the flexible suction-head wall to at least two relatively spaced fastening elements, the length of the flexible suction-head wall in the working state exceeding the distance between the two fastening elements and in that a pressure difference is created along substantially the whole length of the flexible suction-head wall between the higher pressure of the ambient water and a lower pressure on the side of the flexible suction-head wall remote from the ambient water.
  • a preferred method further developed in this respect is characterized in that the flexible suction-head wall is set in a form of skate-shaped cross-section by arranging the two fastening elements on the same side at different distances from the dredgings transport conduit, whilst between the fastening element nearest the dredgings transport conduit and the dredgings transport conduit there is arranged a control-chamber in which substantially the same pressure is maintained as in the dredgings transport conduit and/or in the suction head and in that the shape of the flexible suction-head wall is determined via a flexible outer wall, via the control-chamber as well as via the flexible suction-head wall also in dependence on the higher pressure of the ambient water.
  • the invention furthermore relates to and provides a device for carrying out the method according to the invention.
  • This device for sucking up dredgings from subaqueous ground comprising a suction head and a dredgings transport conduit connected with the former and provided with pump means, said suction head having at least one suction-head lower rim which is level-variably connected by means of at least one flexible suction-head wall with the dredgings transport conduit is characterized in that the shape of the flexible suction-head wall is adjustable in dependence on a pressure difference between the pressure of a suspension stream locally flowing along the flexible suction-head wall and the pressure prevailing on the side of the flexible suction-head wall remote from the suspension stream.
  • the flexible suction-head wall is less deformable near the inlet of the dredgings transport conduit than the further part of the flexible suction-head wall.
  • the invention provides an improvement in a suction head moved along the bottom and having a large working width transverse of the direction of displacement of the suction head and being intended for sucking up material which has been fluidized in advance or which is found in the fluidized form on the bottom.
  • This device according to the invention is characterized in that - viewed in the direction of movement of the suction head along the bottom - the suction head comprises a flexible suction-head wall preceding the entrance of the dredgings transport conduit.
  • this suction head is improved in this respect in that with the aid of water-jet nozzles arranged on the suction-head frame the ground material is loosened by the jets in a region lying in front of and/or above the flexible suction-head wall - viewed in the direction of movement of the suction head.
  • a device for sucking up dredgings from subaqueous ground is improved in that - viewed in the direction of movement of the suction head - a suction-head rim preferably comprising a flexible element and co-operating in closing relationship with the bottom is provided on the front side of the entrance of the dredgings transport conduit, whilst the flexible suction-head wall is arranged downstream of the entrance.
  • a further, preferred device is characterized in that a rim of the flexible suction-head wall remote from the entrance of the dredgings transport conduit is connected with a bottom support, which is level-variably connected with the dredgings transport conduit.
  • An arrangement 40 according to the invention comprising, as shown in Figure 1, on a reduced scale, a vessel 41 having a hold 42 for receiving dredgings 45 furthermore comprises a suction head 6 and a dredgings transport conduit 1 connected with the former and provided with a pump 43, said suction head 6 having a suction-head lower rim 44, which is connected by means of a flexible suction-head wall 4 with the dredgings transport conduit 1.
  • the flexible suction-head wall 4 may consist of an annular collar of rubber or similar, elastic, wear-resistant material, the length of which in the cross-sectional view shown appreciably exceeds the distance 1 between the connecting elements 47 and 48 arranged at different distances from the dredgings transport conduit 1 or on the frame 8 so that in the operative position of the flexible suction-head wall 4 the cross-section has the shape of a skate, whilst a beading 3 of said flexible suction-head wall 4 defines a suction chamber 13.
  • the frame 8 is rigidly secured to the dredgings transport conduit 1.
  • the shape of the flexible suction-head wall 4 is adjustable in dependence on a pressure difference between the pressure P 1 of a suspension stream 10 locally flowing along the flexible suction-head wall 4 and the pressure P 2 prevailing in the ambient water 51 on the side of the flexible suction-head wall 4 remote from the suspension stream 10. Because the flexible suction-head wall 4 has a great freedom of setting itself automatically, an advantageous form of flow of low flow resistance is obtained.
  • the term "suspension stream” is to be understood to mean the stream of slush, water and/or a mixture of water and ground material sucked up by the suction head 6.
  • water jet nozzles 5 are arranged in the suction chamber 13 for keeping the suspension 11 moving.
  • the flexible suction-head wall 4 approaches the bottom 9 at vertical movements of the dredgings transport conduit 1, but it does not or substantially not touch the bottom 9. During these upward and downward movements part of the contents of the suction chamber 13 would be pumped to and fro so that the dredging process would be interrupted. In order to avoid this effect an annular control-chamber 2 having a flexible outer wall 7 adjacent the suction chamber 13 is provided, said chamber alternately receiving and delivering part of the contents of the suction chamber 13.
  • This control-chamber 2 is arranged between an annular connecting element 47 and the dredgings transport conduit 1 and is bounded by the top side 50 of the beading 3 of the flexible suction-head wall 4 and the flexible outer wall 7, which separates the control-chamber 2 from the ambient water 51.
  • This control-chamber 2 communicates with the dredgings transport conduit 1 and/or with the suction chamber 13.
  • the suction head 2 of Figure 2 has a smaller suction chamber 13 so that a higher rate of transport 12 of the suspension 11 is obtained, which prevents grains from settling down.
  • the flexible suction-head wall 4 moves by its inwardly extending beading 3 along the outer side of the dredgings transport conduit 1. Therefore, the suspension 11 to be conducted away at the rate 12 has adequate velocity 14 in the suction chamber 13 and the inlet 21 for preventing settling of the grains.
  • the dredgings transport conduit 1 communicates through orifices 29 provided therein with the control-chamber 2 so that in said chamber 2 prevails the same or substantially the same pressure as in the dredgings transport conduit 1.
  • the shape of the flexible suction-head wall 4 is adjusted in dependence on the condition of the ambient water 51 via the outer wall 7-and the control-chamber 2.
  • suction head 6 of Figures 1 and 2 is described in the foregoing as being annular, it is preferred to construct the suction head 6, as is shown in Figure 3 with two suction-head walls 4 and 54 arranged each on one side of the inlet of the suction chamber 13 and having a substantially identical shape along a given suction width of the suction head 6.
  • the suction head 6 of Figure 3 furthermore differs from that shown in Figures 1 and 2 in that the frame 8 carrying the flexible suction-head walls 4 and 54 is level-variably adjustable with respect to the dredgings transport conduit 1 by means of hydraulic rams 52 controlled on board the vessel 41 and in that said flexible suction-head walls 4 and 54 each have a fairly flexible outer portion 20 and an adjacent, less flexible portion 19 near the inlet 21. In this way the flexible suction-head wall 4, 54 is prevented from partially entering the inlet 21 by suction force and from thus partly clogging the inlet 21.
  • the shape of the flexible suction-head walls 4 and 54 can furthermore be acted upon by pressurized fluid chambers 23 to be pumped up from a distance as shown in Figure 3. By chosing different pressures in the pressure chambers 23 independently of one another through separate air ducts 55, the suspension stream 10 can flow optionally through the inlet 24 or through the inlet 25.
  • a suction head 6 further developed in this respect is illustrated in Figure 4, in which fastening elements 48 of separate frames 8 and 18 respectively are arranged at a high and a low level respectively so that a suspension stream 10 can enter the suction chamber 13 only through an inlet 24.
  • dredgings 28 lying on a ground 9 are caused to form a suspension with the aid of water jets 26 and 27 respectively and conducted away through the inlet 24, the suction cham- iber 13 and the dredgings conveying conduit 1, whilst the flexible suction-head wall 54 lying on the ground 9 ensures local closure.
  • sand 16 collected on a foundation mat 15 can be removed, whilst, if necessary, the suction head 6 is displaced in the direction indicated by the arrow 56.
  • FIG. 5 shows a suction head 6 according to the invention, which forms part of a drag head 37 dragged along the bottom 9 in the direction indicated by the arrow 57.
  • the drag head 37 bears on the bottom 9 by a heel rim 34 and the dredgings transport conduit constructed in the form of a drag pipe 33 is connected with the vessel 41.
  • a flexible suction-head wall 30 is provided at the fastening area 32 and carried on its rear side by a frame 31 of the drag head 37.
  • the frame 31 bears by means of skids 36 on the bottom 9 in an adjustable manner.
  • a suction gap s is formed in which the dredgings on the bottom 9 are readily eroded by the high erosion rate and are conducted away in the suspension stream 10 through the drag pipe 33.
  • the setting members 58 may be formed by an adjustable bolt-hole joint.
  • the suction head 6 of Figure 6 has at least one flexible suction-head wall 4, which is fastened on its side remote from the suspension stream 10 at the areas 62 to inhibiting elements 60 formed by stay wires connected with fastening elements 61 of the frame 8, said inhibiting elements 60 holding the flexible suction-head wall 4 within the maximum distance corresponding to the length of the stay wires with respect to said fastening elements 61 in order to avoid undesirable deformation of the suction-head wall 4.
  • the suction head 6 is indicated by broken lines and designated by reference numerals with an apostrophe at a higher level with respect to the bottom 9.
  • a barrier plate 85 shown in Figure 6 is used for enhancing the pressure P 2 .
  • Figure 7 shows a variant of Figure 6 with a flexible suction-head wall 4, whose undesirable, inadmissible deformation is inhibited by a comparatively rigid portion 19 of large wall thickness, which is guided by the outer side of the dredgings transport conduit 1 and a guide element 63 rigidly secured to the frame 8.
  • the drag head 37 of Figure 8 comprises a flexible suction-head wall 54, which is fastened to a pivotable frame 68, which is pivotable about a pivotal axis 69 between a cutting position indicated by solid lines and a non-cutting position indicated by broken lines and designated by reference numerals with apostrophe.
  • the frame 68 carries a knife 70, which works the bottom 9 in the cutting position and cuts loose dredgings 28.
  • the flexible suction-head wall 54 In the non-cutting position the flexible suction-head wall 54 is in its working position 54'.
  • the knife 70 is only used for leaving a smooth bottom behind.
  • the drag head 37 of Figures 9 to 11 comprises a flexible suction-head wall 4, the outer rim of which is fastened to fastening elements 47 and 48 connected with a frame 8, which is pivotable about a horizontal shaft 71 and which bears on the bottom 9 through lateral skids 49 in order . to hold the lower rim 44 of the suction_head formed by the lower part of the flexible suction-head wall 4 at a distance of the gap s for the erosion of the bottom 9.
  • Figure 10 shows the drag head 37 of Figure 9 at a greater suction depth and Figure 11 shows that a large stone 59 can be sucked up with a matching deformation of the suction-head wall 4, whilst in a normal situation the suspension stream 10 has a narrow passage along a long trajectory 17 and even at the entrance 21.
  • the suction-head wall 4 has to be flexible in the flow direction of the suspension stream 10, but transverse thereof it may be rigid. As shown in Figure 12 the suction-head wall 4 consists of a skin 39 having reinforcing ribs 38 extending in a transverse direction. The suction-head wall 4 is displaceable and joins in a water-tight manner side cheeks 35 of the frame 8 and side walls 46 of the drag pipe 33 by means of sealing tongues 22.
  • Figure 13 shows that a tongue 22 engages in sealing relationship an exploring rim 67 of the side wall 46 and the side cheek 35.
  • the drag head 37 of Figure 16 is distinguished from that of Figure 9 in that the beading 3 is provided with a flow guide strip 73 having a pressure-equalizing opening 72, the free rim 74 of which is held in contact with the top wall 75 of the drag pipe 33.
  • FIG 17 shows a further development of the drag head 37 of Figure 5 in which the flexible suction-head wall 4 is fixed between a fastening member 48 on the outer rim 77 and a fastening member 47 engaging the inner rim 78 of the suction-head wall 4, said fastening member 47 being arranged in a displaceable manner with respect to he drag pipe 33 by pivotably connecting the same by means of a pivotal bar 79 on a shaft 80 with the drag pipe 33 and by means of a pivotal rod 81 about a shaft 82 with the frame 8.
  • the fastening member 47 is rigidly secured to the pivotal rod 79 and the pivotal rod 79 is pivotable with respect to the pivotal rod 81 by means of a hinge 83.
  • the inhibiting elements 60 operate herein in the same manner as the inhibiting elements 60 of Figure 9.
  • the pivotal rod 81 has a setting member 84 for adjusting its length.
  • the flexible suction-head wall 4 is preferably made of a skin of elastic material having a rigidity increasing from the outer rim 77 towards the inner rim 78.
  • the drag head 37 of Figure 18 comprises a flexible suction-head wall 4, whose inner rim 78 is rigidly connected with the top wall 75 of the drag pipe 33 and whose outer rim 77 is slidably bearing on the frame 8. Viewed in a direction away from the part of the suction-head wall 4 located near the outer rim 77, the rigidity in the direction of flow is materially greater than that of the part of the suction-head wall 4 bounding the inlet 21 and being held in the desired form by means of the inhibiting elements 60.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Air Transport Of Granular Materials (AREA)
EP80200862A 1980-09-12 1980-09-12 Procédé et dispositif à drague suceuse pour aspirer des matières draguées Ceased EP0047803A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP80200862A EP0047803A1 (fr) 1980-09-12 1980-09-12 Procédé et dispositif à drague suceuse pour aspirer des matières draguées

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP80200862A EP0047803A1 (fr) 1980-09-12 1980-09-12 Procédé et dispositif à drague suceuse pour aspirer des matières draguées

Publications (1)

Publication Number Publication Date
EP0047803A1 true EP0047803A1 (fr) 1982-03-24

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EP80200862A Ceased EP0047803A1 (fr) 1980-09-12 1980-09-12 Procédé et dispositif à drague suceuse pour aspirer des matières draguées

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5647691A (en) * 1994-11-14 1997-07-15 Wirth; John C.J. Method and apparatus for transferring mud and silt
WO2001014649A1 (fr) * 1999-08-21 2001-03-01 Psl Technology Limited Appareil et procede pour excavation dans un fond marin
WO2003044285A1 (fr) * 2001-11-22 2003-05-30 Graham Albrecht Dispositif de collecte de gravier submerge
WO2005052267A1 (fr) * 2003-11-27 2005-06-09 Yi-Zoong Kim Dispositif de decoupe a sac de liquide
EP2434061A1 (fr) * 2010-09-28 2012-03-28 Baggerwerken Decloedt en Zoon N.V. Dispositif et procédé de dragage sans endommager les structures présentes sur le fond à draguer
CN104878780A (zh) * 2015-05-28 2015-09-02 中交一航局第二工程有限公司 沉管隧道基床整平过程中定时清淤防淤系统及方法
NO20221055A1 (en) * 2022-10-04 2024-04-05 Imo Mare As Device for removal of non-consolidated mass at seabed

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1840606A (en) * 1929-02-27 1932-01-12 Scheffauer Frederick Carl Self-adjusting draghead
GB1060825A (en) * 1962-08-21 1967-03-08 Johnston Brothers Eng Improvements in or relating to suction nozzles for suction refuse collecting vehicles
DE1634724A1 (de) * 1966-12-29 1970-08-27 Bodine Jun Albert George Baggerverfahren und zugehoerige Vorrichtung
DE1928417A1 (de) * 1969-06-04 1970-12-10 Orenstein & Koppel Ag Saugkopf fuer Nassbagger
FR2074565A1 (fr) * 1970-01-05 1971-10-08 Regie Autonome Transports
US3975842A (en) * 1973-10-15 1976-08-24 Bos Kalis Westminster Group N.V. Method and apparatus for dredging employing a transport fluid flowing in substantially closed recirculating course
US4053181A (en) * 1976-01-20 1977-10-11 Nakaji Saito Seabed mining utilizing circulating current based on water level differences

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1840606A (en) * 1929-02-27 1932-01-12 Scheffauer Frederick Carl Self-adjusting draghead
GB1060825A (en) * 1962-08-21 1967-03-08 Johnston Brothers Eng Improvements in or relating to suction nozzles for suction refuse collecting vehicles
DE1634724A1 (de) * 1966-12-29 1970-08-27 Bodine Jun Albert George Baggerverfahren und zugehoerige Vorrichtung
DE1928417A1 (de) * 1969-06-04 1970-12-10 Orenstein & Koppel Ag Saugkopf fuer Nassbagger
FR2074565A1 (fr) * 1970-01-05 1971-10-08 Regie Autonome Transports
US3975842A (en) * 1973-10-15 1976-08-24 Bos Kalis Westminster Group N.V. Method and apparatus for dredging employing a transport fluid flowing in substantially closed recirculating course
US4053181A (en) * 1976-01-20 1977-10-11 Nakaji Saito Seabed mining utilizing circulating current based on water level differences

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5647691A (en) * 1994-11-14 1997-07-15 Wirth; John C.J. Method and apparatus for transferring mud and silt
WO2001014649A1 (fr) * 1999-08-21 2001-03-01 Psl Technology Limited Appareil et procede pour excavation dans un fond marin
WO2003044285A1 (fr) * 2001-11-22 2003-05-30 Graham Albrecht Dispositif de collecte de gravier submerge
WO2005052267A1 (fr) * 2003-11-27 2005-06-09 Yi-Zoong Kim Dispositif de decoupe a sac de liquide
KR100532696B1 (ko) * 2003-11-27 2005-11-30 김이중 액체백을 이용한 유체 차단장치
US7690134B2 (en) 2003-11-27 2010-04-06 Yi-Zoong Kim Cutoff device with liquid bag
EP2434061A1 (fr) * 2010-09-28 2012-03-28 Baggerwerken Decloedt en Zoon N.V. Dispositif et procédé de dragage sans endommager les structures présentes sur le fond à draguer
BE1019522A4 (nl) * 2010-09-28 2012-08-07 Baggerwerken Decloedt & Zn N V Baggerinrichting en werkwijze voor het baggeren zonder beschadiging van in de te baggeren bodem aanwezige structuren.
CN104878780A (zh) * 2015-05-28 2015-09-02 中交一航局第二工程有限公司 沉管隧道基床整平过程中定时清淤防淤系统及方法
NO20221055A1 (en) * 2022-10-04 2024-04-05 Imo Mare As Device for removal of non-consolidated mass at seabed
WO2024076242A1 (fr) * 2022-10-04 2024-04-11 Imo Mare As Dispositif d'extraction de masse non consolidée au fond de la mer
NO347988B1 (en) * 2022-10-04 2024-06-03 Imo Mare As Device for removal of non-consolidated mass at seabed

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Inventor name: BAKKER, ADRIAAN DANIEL