US3630400A - Method of loading a hopper of a suction dredger with sand - Google Patents

Method of loading a hopper of a suction dredger with sand Download PDF

Info

Publication number
US3630400A
US3630400A US874212A US3630400DA US3630400A US 3630400 A US3630400 A US 3630400A US 874212 A US874212 A US 874212A US 3630400D A US3630400D A US 3630400DA US 3630400 A US3630400 A US 3630400A
Authority
US
United States
Prior art keywords
hopper
sand
suction dredger
suspension
loading
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.)
Expired - Lifetime
Application number
US874212A
Other languages
English (en)
Inventor
Jan De Koning
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.)
NV INGENIEURSBUREAU VOOR SYSTEMEN EN OCTROOIEN SPANSTAAL BINNENWEG
SPANSTAAL
Original Assignee
SPANSTAAL
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 SPANSTAAL filed Critical SPANSTAAL
Application granted granted Critical
Publication of US3630400A publication Critical patent/US3630400A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B27/00—Arrangement of ship-based loading or unloading equipment for cargo or passengers
    • B63B27/24—Arrangement of ship-based loading or unloading equipment for cargo or passengers of pipe-lines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65G—TRANSPORT OR STORAGE DEVICES, e.g. CONVEYORS FOR LOADING OR TIPPING, SHOP CONVEYOR SYSTEMS OR PNEUMATIC TUBE CONVEYORS
    • B65G53/00—Conveying materials in bulk through troughs, pipes or tubes by floating the materials or by flow of gas, liquid or foam
    • B65G53/30—Conveying materials in bulk through pipes or tubes by liquid pressure
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F7/00—Equipment for conveying or separating excavated material
    • E02F7/04—Loading devices mounted on a dredger or an excavator hopper dredgers, also equipment for unloading the hopper
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F7/00—Equipment for conveying or separating excavated material
    • E02F7/06—Delivery chutes or screening plants or mixing plants mounted on dredgers or excavators
    • E02F7/065—Delivery chutes or screening plants or mixing plants mounted on dredgers or excavators mounted on a floating dredger
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/7287—Liquid level responsive or maintaining systems
    • Y10T137/7339—By weight of accumulated fluid
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/8593—Systems
    • Y10T137/86236—Tank with movable or adjustable outlet or overflow pipe
    • Y10T137/8626—Swinging outlet pipe or spout

Definitions

  • the invention relates to a method of loading a hopper of a floating suction dredger with sand.
  • a suspension of sand and water is pumped into the hopper in a first step.
  • the hopper contains only a little amount of sand.
  • additional suspension is pumped into the hopper during. simultaneously draining off until the amount of sand does not increase anymore.
  • the settling of sand depends on the size of the grains and the flow velocity of the suspension.
  • the free flow area above the settled sand decreases as sand settles, resulting in an increase of the flow velocity of the suspension up to a value preventing further settlement of sand.
  • this suspension is drained off with all its sand.
  • the quotient of the sand volume and the hopper volume, which sand volume can be reached with a given grain size of the sand, a given capacity of the pump and a given hopper cross section is called the bulking factor.
  • the hopper of the known suction dredger has a volume in m substantially equal to half its maximum permissable carrying capacity.
  • hopper cannot be filled completely with sand owing to said bulking factor it has been proposed already providing the hopper with an upstanding upper edge comprising draining off flaps, for loading the hopper with a little more sand owing to the increased free flow area above the settled sand.
  • a third loading step during which no suspension is pumped into the hopper, sand is allowed to settle. After that the water is drained off by suddenly lowering the draining off flaps. This third loading step may be reproduced.
  • the invention has the object to shorten the loading time.
  • the invention provides a method of loading a hopper of floating suction dredger with sand, wherein a suspension of sand and water is pumped into the hopper during a loading operation carried out in at least two steps:
  • the invention provides a floating suction dredger comprising a hopper and a pump for pumping suspension of sand and water into said hopper, characterized by load-measuring means controlling adjustable drain means.
  • the invention further has the object to load the floating suction dredger suction dredger up to its maximum permissable carrying capacity with sand.
  • the volume of the hopper is so great, that the suction dredger is loaded up to its maximum permissable carrying capacity when the hopper is substantially completely filled with sucked up suspension of sand and water.
  • the drain means are put in operation as soon as the suction dredger is loaded up to its maximum permissable carrying capacity during simultaneously pumping of additional suspension into the hopper.
  • the drain means preferably have a capacity exceeding the pump capacity.
  • the drain means comprise at least one drain siphon having a depth-adjustable inlet.
  • the floating suction dredger preferably comprises a safety device which is controlled by load-measuring means and which becomes operative when the weight of the load of the hopper exceeds a predetermined value.
  • This safety device may actuate an alarm device, may put the pump out of working and/or may in case of emergence put in operation unloading means for discharging sand from the hopper.
  • FIG. la and lb show graphs of the known method for loading a known suction dredger.
  • FIG. 1c shows a cross section of said known suction dredger
  • FIG. 2a and 2b show graphs of the method according to the invention for loading a suction dredger
  • FIG. 3 shows a longitudinal section of a preferred embodiment of a suction dredger according to the invention
  • FIG. 4 shows a plan view of the suction dredger of FIG. 3
  • FIG. 5 shows diagrammatically the control and safety devices of the suction dredger of FIGS. 3 and 4.
  • FIGS. la and 2a interrupted lines show the suspension volume and uninterrupted lines show the sand weight at any time during loading operation.
  • FIGS. lb and 2b interrupted lines show the suspension weight and uninterrupted lines show the sand weight at any time during loading operation.
  • FIGS. 1 and 2 are based on equal maximum permissable carrying capacities of the suction dredgers and on equal suspension flows which can bepumped into the hopper, said suspension flows having equal rates of sand.
  • a suction dredger For conveying a volume V of wet sand (FIG. 1a) in the known method a suction dredger is applied having a maximum hopper volume V,,, which can be reduced by lowerable draining ofi flaps 6 to a volume V,
  • suspension is pumped into the hopper 2 of the suction dredger 1 of FIG. lc during a first-loading step 3 starting at the point of time 0 and ending at the point of time A at which the hopper 2 is completely filled up to its upper edge 5.
  • the hopper 2 has draining off flaps 6 being closed during the firstloading step 3.
  • the volume V and also the weight G increase considerably.
  • the hopper volume is than V, In a subsequent fourth-loading step 8 the draining off flaps 6 are closed and the hopper 2 is filled with additional suspension in the period FIG. In the period GH the sand of the suspension is allowed to settle, during which period no suspension is pumped into the hopper 2. At the point of time II the required sand volume V is obtained.
  • FIGS. 3 and 4 a floating suction dredger for carrying out the method according to the invention is shown.
  • This suction dredger consists of a trailing suction dredger having a hopper 12, a pump 10 connected to a trailing suction pipe 9 at its suction side and to a supply pipe 15 at its pressure side and having swingable draining off siphons 16 forming draining off means...
  • Each draining off siphon 16 comprises a fixed siphon pipe 41 connected to a pipe 20 and through a flexible conduit 42 to a movable siphon pipe 41 pivotably mounted at the siphon pipe 41.
  • the movable siphon pipe 41 is operated by means of a hydraulic jack 17 and has an inlet nozzle 43.
  • sand outlets 18 are provided with discharge valves 19.
  • the hopper 12 could be divided into two longitudinal parts.
  • the suction dredger could comprise two hoppers 12 arranged behind each other.
  • suspension sucked up through the suction pipe 9 is pumped by the pump 10 through the supply pipe into the hopper 12 until the suction dredger 11 is loaded up to its maximum permissable carrying capacity.
  • the hopper 12 now contains sand and water of which sand a volume V has been settled at the point of time B.
  • the draining off siphons 16 now are still in the position 16,.
  • FIG. 2 clearly shows, that the total required loading time 0C of the loading steps 13 and 14 of the method according to the invention is considerably less than the total required loading time OH of the known method, whereas the sand volume V is about equal to the sand volume V of FIG. 1.
  • the load is measured with pressure pick ups 22,, 22 and 22, each arranged at the bottom of the suction dredger 11 and each comprising a pressure sensitive membrane 33, limiting a chamber 24 connected to the outboardwater 21.
  • Each pressure pickup 22,, 22 and 22, picks up the pressure corresponding with its depth in the outboardwater, which is a measure for the draught of the suction dredger 11 and the weight of the load.
  • Nine pressure pickups 22,, 22, and 22, are provided: at port board, in the longitudinal center plane and at starboard respectively as well as at the front, the rear and the midpart of the suction dredger.
  • the corresponding hopper'volume is adjusted automatically, for maintaining the suction dredger loaded at its maximum permissable carrying capacity.
  • FIG. 5 the automatic control means for carrying out the method according to the invention are shown diagrammatically.
  • the pressure pickups 22,, 22, and 22, provide signals to receivers 25,, 25, and 25, respectively. From these signals the draughts of the corresponding ship parts are determined in calculating units 26,, 26, and 26,. The outputs of these calculating units are provided to the draught-, list-and trim-calculating unit 27, providing signals to the draught indicator 28, trimindicator 29 and the safety device 30, the calculating unit 26, providing signals concerning the starboard draught to the comparing and calculating device 31, which in turn provides signals to the signal converters 32,. These signal converters 32, provide signals to the control valves 33, for controlling the hydraulic jack 17, of the draining off siphon 16,. Calculating unit 31, provides signals concerning the central draught to both signal converters 32, and 32,, whereas calculating unit A, in the same way provides signals to signal converter 32, and thus operates the jack 17, of draining off sip hon 16,.
  • the list of the suction dredger owing to unequally loading may be corrected.
  • the safety device 30 provides signals to an alarm device 34 formed by a red light, an accoustic alarm device 35 and to an automatic safety unit 36 providing signals for lowering the draining off siphons 16, and 16, through signal converters 32, and 32,, signals for putting the pump 10 out of work through signal converter 37 and signals for opening the sand discharge valves 19 through signal converter 38.
  • the draining off siphons 16, and 16,, the pump 10, and the discharge valves 19 may be controlled from an operating panel by hand through the hand operated members 40,, 40, and 39.
  • the hopper 12 When sucking up a suspension having a low rate of sand, the hopper 12 which has a great volume, may be completely filled, although the suction dredger is not yet loaded up to its maximum permissable carrying capacity. In this case suspension is still pumped into the hopper, during a period in which the draining off siphons are kept in their positions 16,, and in which liquid mainly consisting of water is drained off over the upper edge 44 of the hopper 12.
  • the pump 10 is put out of work and the sand in the suspension standing above settled sand is allowed to settle in a subsequent period, at the end of which the water standing above all settled sand is drained off by lowering the draining off siphons up to the surface of sand. In this way the suction dredger is even loaded less than its maximum permissable carrying capacity during the trip to the unloading place.
  • the suction dredger 11 preferably comprises a water pump 45 pumping up outboardwater 21 through inlet pipe 46 and being connected by conduits 47 to jet-nozzles 48 mounted in the siphon pipes 41. These jet nozzles function like jet pumps for starting the siphon operation of the draining off siphons 16, when necessary.
  • the liquid above the settled sand may be drained off owing to the jet nozzles 48 operating like jet pumps. After draining off operation the draining off siphons are raised into their uppermost position.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Mechanical Engineering (AREA)
  • Civil Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Ocean & Marine Engineering (AREA)
  • Ship Loading And Unloading (AREA)
  • Jet Pumps And Other Pumps (AREA)
  • Treatment Of Sludge (AREA)
US874212A 1968-11-08 1969-11-05 Method of loading a hopper of a suction dredger with sand Expired - Lifetime US3630400A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NL6815921A NL6815921A (fr) 1968-11-08 1968-11-08

Publications (1)

Publication Number Publication Date
US3630400A true US3630400A (en) 1971-12-28

Family

ID=19805104

Family Applications (1)

Application Number Title Priority Date Filing Date
US874212A Expired - Lifetime US3630400A (en) 1968-11-08 1969-11-05 Method of loading a hopper of a suction dredger with sand

Country Status (9)

Country Link
US (1) US3630400A (fr)
JP (1) JPS5114799B1 (fr)
BE (1) BE741283A (fr)
DE (1) DE1955944C3 (fr)
FR (1) FR2022906A1 (fr)
GB (1) GB1285894A (fr)
HK (1) HK23777A (fr)
MY (1) MY7500302A (fr)
NL (1) NL6815921A (fr)

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3812984A (en) * 1971-05-06 1974-05-28 J Cladingboel Transport of woodchips
US4008155A (en) * 1972-11-21 1977-02-15 William Gummer Castell Apparatus for disposal of effluents
US4012219A (en) * 1975-04-18 1977-03-15 Walter Josephs Method for reclaiming variegated wastes
US4020573A (en) * 1974-02-25 1977-05-03 Ballast-Nedam Group N.V. Method and device for sucking up a solid substance from a stock
US4149480A (en) * 1977-07-29 1979-04-17 Adriaan Volker Baggermaatschappij B.V. Hopper barge
US4172617A (en) * 1975-11-12 1979-10-30 Ingenieursbureau voor Systemem en Octrooien "Spanstaal" B.V. Suction dredger vessel and method of loading the hold of the same
US4245932A (en) * 1977-07-12 1981-01-20 Ingenieursbureau voor Systemen en Octrooien "Spanstaal" B. V. Suction dredger and method of loading the same
US4282661A (en) * 1978-11-01 1981-08-11 B.V. Scheepswerf en Reparatie bedrijf "Breebot" Towing suction device for a dredging craft
US5042178A (en) * 1990-04-13 1991-08-27 Dutra Bill T Apparatus and process for solid dredge material disposal
GB2309940A (en) * 1996-02-07 1997-08-13 Lim Tung Method and Apparatus for forming a dyke, dam or river bank from sludge
US20170275849A1 (en) * 2014-08-26 2017-09-28 Ihc Holland Ie B.V. Adjustable overflow system
EP3294957A4 (fr) * 2015-05-08 2019-02-13 Akabotics, LLC Système de microdragage et procédé d'utilisation de ce système
US11247926B2 (en) * 2018-07-02 2022-02-15 II Richard L. Edgell System and method to remove micro plastic material from water environments

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL167912C (nl) * 1970-12-01 1982-02-16 Bos & Kalis Baggermaatsch Inrichting voor het cyclisch bepalen van de optimale beladingstoestand van een met afnemende snelheid te beladen transportmiddel.
NL175212C (nl) * 1975-11-12 1984-10-01 Spanstaal Zuigbaggervaartuig en werkwijze voor het beladen van een ruim van een zuigbaggervaartuig.
DE2755125A1 (de) * 1977-12-10 1979-06-13 Cassella Ag Verfahren zur entfernung von schlamm aus gewaessern
JPS5680625U (fr) * 1979-11-26 1981-06-30
JPH0439019U (fr) * 1990-08-01 1992-04-02
CN112378458B (zh) * 2020-12-04 2022-06-03 四川长虹电器股份有限公司 一种无人值守采砂船运行监控监测方法

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US689741A (en) * 1901-09-10 1901-12-24 Alexander Mcdougall Vessel for transporting granular substances.
US764784A (en) * 1903-12-08 1904-07-12 Smit & Zoon L Apparatus for loading suction-dredges, &c.
US1521704A (en) * 1921-11-17 1925-01-06 Smith Engineering Works Sand-settling tank
US1750095A (en) * 1928-06-06 1930-03-11 Ewig Friedrich Hold for dredgers
US2052481A (en) * 1932-04-11 1936-08-25 Willis H Miller Hydraulic dredge apparatus
US3375928A (en) * 1965-12-28 1968-04-02 United States Steel Corp Method and apparatus for controlling the level of an interface
US3381709A (en) * 1965-07-21 1968-05-07 Pregno Dario Devices for drawing liquid from tanks and the like

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US689741A (en) * 1901-09-10 1901-12-24 Alexander Mcdougall Vessel for transporting granular substances.
US764784A (en) * 1903-12-08 1904-07-12 Smit & Zoon L Apparatus for loading suction-dredges, &c.
US1521704A (en) * 1921-11-17 1925-01-06 Smith Engineering Works Sand-settling tank
US1750095A (en) * 1928-06-06 1930-03-11 Ewig Friedrich Hold for dredgers
US2052481A (en) * 1932-04-11 1936-08-25 Willis H Miller Hydraulic dredge apparatus
US3381709A (en) * 1965-07-21 1968-05-07 Pregno Dario Devices for drawing liquid from tanks and the like
US3375928A (en) * 1965-12-28 1968-04-02 United States Steel Corp Method and apparatus for controlling the level of an interface

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3812984A (en) * 1971-05-06 1974-05-28 J Cladingboel Transport of woodchips
US4008155A (en) * 1972-11-21 1977-02-15 William Gummer Castell Apparatus for disposal of effluents
US4020573A (en) * 1974-02-25 1977-05-03 Ballast-Nedam Group N.V. Method and device for sucking up a solid substance from a stock
US4012219A (en) * 1975-04-18 1977-03-15 Walter Josephs Method for reclaiming variegated wastes
US4172617A (en) * 1975-11-12 1979-10-30 Ingenieursbureau voor Systemem en Octrooien "Spanstaal" B.V. Suction dredger vessel and method of loading the hold of the same
US4245932A (en) * 1977-07-12 1981-01-20 Ingenieursbureau voor Systemen en Octrooien "Spanstaal" B. V. Suction dredger and method of loading the same
US4149480A (en) * 1977-07-29 1979-04-17 Adriaan Volker Baggermaatschappij B.V. Hopper barge
US4282661A (en) * 1978-11-01 1981-08-11 B.V. Scheepswerf en Reparatie bedrijf "Breebot" Towing suction device for a dredging craft
US5042178A (en) * 1990-04-13 1991-08-27 Dutra Bill T Apparatus and process for solid dredge material disposal
GB2309940A (en) * 1996-02-07 1997-08-13 Lim Tung Method and Apparatus for forming a dyke, dam or river bank from sludge
US20170275849A1 (en) * 2014-08-26 2017-09-28 Ihc Holland Ie B.V. Adjustable overflow system
US10676895B2 (en) * 2014-08-26 2020-06-09 Ihc Holland Ie B.V. Adjustable overflow system
EP3294957A4 (fr) * 2015-05-08 2019-02-13 Akabotics, LLC Système de microdragage et procédé d'utilisation de ce système
US10329735B2 (en) 2015-05-08 2019-06-25 Akabotics, Llc Microdredging system
AU2016259542B2 (en) * 2015-05-08 2020-09-03 Coolfish Robotics Llc Microdredging system and method of using the same
US11247926B2 (en) * 2018-07-02 2022-02-15 II Richard L. Edgell System and method to remove micro plastic material from water environments

Also Published As

Publication number Publication date
DE1955944B2 (de) 1974-02-07
DE1955944A1 (de) 1970-05-21
FR2022906A1 (fr) 1970-08-07
DE1955944C3 (de) 1974-09-12
BE741283A (fr) 1970-05-05
MY7500302A (en) 1975-12-31
HK23777A (en) 1977-05-27
NL6815921A (fr) 1970-05-12
GB1285894A (en) 1972-08-16
JPS5114799B1 (fr) 1976-05-12

Similar Documents

Publication Publication Date Title
US3630400A (en) Method of loading a hopper of a suction dredger with sand
US5129167A (en) Method of and apparatus for preventing diffusion of muddy water in sand gathering equipment
US3975842A (en) Method and apparatus for dredging employing a transport fluid flowing in substantially closed recirculating course
US3693272A (en) A floating tower for underwater dredging
US3739503A (en) Hydraulic dredge having articulated ladder and swell compensator
US4490044A (en) Automatic slurry concentration control system
US3224121A (en) Apparatus for optimizing dredge production
US5259130A (en) Floating grab installation for the recovery of sand and gravel
WO1995021303A1 (fr) Procede de dragage a l'aide d'une drague suceuse porteuse, et drague suceuse porteuse pour sa mise en ×uvre
US4631844A (en) Hydraulic shovel dredge system
US3314184A (en) Method and apparatus for transferring fish by pumping
CN213572127U (zh) 一种疏浚砂净化及高浓度装驳系统
US5167841A (en) Removing material debris from body of water
US3878946A (en) Apparatus for loading a hopper of a suction dredger with sand
US3698573A (en) Method and apparatus for loading a dredging vessel with dredging spoil
US3631997A (en) Method of loading the hold of a vessel with dredging spoil
EP0023235B1 (fr) Navire transportant des matériaux dragues
US5445093A (en) Unloading facility for flexible water transporting barges
US3999566A (en) Method and apparatus for discharging overboard excess water from hopper of hopper suction dredger or barge or scow
US3212822A (en) Apparatus for pumping objects to higher levels
US3497054A (en) Barge unloading system
US2289260A (en) Dredging machine
JPH09177086A (ja) 浮体の自動姿勢制御装置
US4374504A (en) Suction dredger barge
CN112095705A (zh) 一种疏浚砂净化及高浓度装驳系统