CA1178301A - Suction hopper dredger - Google Patents
Suction hopper dredgerInfo
- Publication number
- CA1178301A CA1178301A CA000407859A CA407859A CA1178301A CA 1178301 A CA1178301 A CA 1178301A CA 000407859 A CA000407859 A CA 000407859A CA 407859 A CA407859 A CA 407859A CA 1178301 A CA1178301 A CA 1178301A
- Authority
- CA
- Canada
- Prior art keywords
- ladder
- suction
- suction tube
- suction head
- winch
- 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
Links
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
- E02F3/905—Manipulating or supporting suction pipes or ladders; Mechanical supports or floaters therefor; pipe joints for suction pipes
Landscapes
- 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)
- Load-Engaging Elements For Cranes (AREA)
Abstract
ABSTRACT
Suction hopper dredger having its ladder tackle adapted for controllable positioning of its suction implement on an ocean bottom.
Suction hopper dredger having its ladder tackle adapted for controllable positioning of its suction implement on an ocean bottom.
Description
~1 7~3;~
This invention relates to a suction hopper dredger which is adapted to operate at great depths.
The present invention provides a suction hopper dredger, comprising a ladder, a suction tube which is carried on the end of the ladder, a pump arranged on the ladder, winch-operated tackles for the ladder and the suction tube, for one or more of which tackles a constant tension winch is to be used, and a well in which the assembly of ladder and suction tube is to be received, wherein the suction tube is pivotally connected to the ladder end and is positioned in the longitudinal direction opposed to the ladder, with the suction tube tackle being reeved on the ladder so that an upper part thereof extends from the suction tube winch to a pulley block on the ladder end, an intermediate part extends from said pulley block to a second pulley block which is arranged higher on the ladder, and a lower part extends from said second pulley block to the suction tube end, said upper and lower parts running downwardly substantiaily parallel to each other.
The manner of reeving the suction tube tackle on the ladder ensures that the motions of the respective tackles of the ladder and the suction tube are decoupled, whereby the positioning of the suction head is controllable in a more positive manner.
The invention is hereinafter first compared to another, less favourable way of outrigging the suction head and is further described in more detail in view of an embodiment thereof as represented in the accompanying drawings, wherein:-Figures 1 and 2 are side views of a dredger vessel illustrating a prior art arrangement of a suction hopper;
,.,j Figure 3 is a somewhat schematic side view of a dredger .
;
- ~1 7~;~30~
vessel in accordance with the invention;
Figure 4 is a view similar to Figure 3 illustrating the successive positions of the suction hopper in passing over an obstacle;
Figures 5a and 5b illustrate the suction hopper retractea within the dredger vessel;
Figures 6a and 6b illustrate the arrangement during repair of the suction head; and Figures 7a and 7b illustrate the arrangement of the suction hopper during replacement of the suction connection piece.
Figures 1 and 2 show for comparison another less favour-able way of tackling with hauled-in, and payed-out suction pipe-line, respectively; and figures 3-7 show a suction hopper dredger with the herein proposed novel suction pipeline carrying system.
The hopper dredger as illustrated in figures 1 and 2 has the disadvantage that the deflection of the suction head 6 which is carried on the end of the suction pipeline 1 is experienced in an augmented manner as the sum of the deflections of each of the articulated pipeline sections and is thus difficult to be con-trolled in a positive manner.
Disadvantages of the system suction pipes 1:
a. the suction pipe must be lowered alongside the hull, and to avoid that the soil must be transported higher than the water level to the pump 2; for this reason, in deep water, a special pump 4 must be installed in the suction pipe 1, which requires a pipe of heavy construction;
b. the water resistance 5 caused by the speed of the vessel, produces a pressure on the pipe l; to compensate this , : , .. .
11~783~
pressure a very heavy weight must be mounted to the suction head 6;
c. all forces must be borne by specially constructed hinging, heave compensated shear legs 7;
d. operating this type of ship in ice-sea conditions, with the outwardly protruding suction pipe and hoisting lines, is asking for trouble when also working in areas with ice-floes;
e. repairs to the suction head, shear legs and flexible hoses must be carried out in the open air.
DESCRIPTION OF THE PRINCIPLE
The pump ladder 8 on which the pumps 9 are arranged is carried and manoeuvred, as illustrated in figure 3, by a constant tension winch 10 preferably with heave-~ompensator. In its upper-most or retracted position the ladder 8 is contained in a well amidships as illustrated in the drawings.
When lowering the ladder 8 to a deep bottom 16, the wire length 11 from the ladder winch 10 increases. The wire 13 carrying the suction head 14 is reeved on the ladder 8 and its hoisting part 12 is controlled by the suction head winch 15. With the suction head winch 15 stopped and the ladder 8 moving up and down at con-stant tension, the suction head 14 will retain its position on the deep bottom 16.
When the suction bottom depth 16 is decreased, as indi-cated by 17, the influence of the movement of the pump ladder 8 on the suction head 14 will increase. This can be compensated by removing or adding tackle parts 13a, 13b of the suction head wire 13 as illustrated in figure 3.
THE WORKING PRINCIPLE OF THE HOPPER LADDER
When the suction head 14 meets an obstacle, as illus-~ : .
., : ' . ' :
, i ~L11 7~3(3~
trated in figure 4~the constant tension winch 10 will release wire 11 due to the fact that the ladder 8 will be pulled astern by the suction head 1~.
As the hoisting wire 11 of the ladder 8 increases in length, the length of the hoisting wire 12 of the suction head 14 will automatically also increase. Consequently the wire 13 decreases in length and will lift the suction head 14.
In the position as per c, the suction head will again reach the soil and the ladder 8 will tend to reposition itself and recover its position at d, as figure 4 illustrates.
This recovery of position will not have any influence on the position of the ship in view of the ship's mass of 45,000 tons moving continuously, in figure 4 the positions a, b, c, d of the suction head 14 correspond with the positions a, b, c and d of the ship in its onward motion.
In figures 5a and 5b is illustrated that above the pump, underneath the wheel house, a pump-repair-shop is arranged. The pumps for this ship will have a total weight of 30 to 50 tons, with separate parts of the pumps weighing about 15 tons. When the pump 9 must be replaced, this can be done by lowering the pump ladder, as in figure 5b, connecting the pump to special hooks on rails and bringing the ladder again underneath the new replacement pump 18 to install it~ This system will save considerable working time.
In a later stage the pump 1~ can be repaired and made ready for reinstallation.
The advantage of this system is the fact that no work has to be carried out in the open air.
Figures 6a and 6b illustrate that when repair of the ~.
, 33~3~
suction head 14 has to be carried out, a specially constructed repair pontoon 14b can be brought into position underneath the suction head, by rails 14c. Now the suction head can be repaired or replaced. The suction head can be transported into a repair shop 19 and repaired inside the vessel.
Figures 7a and 7b illustrate that to turn the pump ladder in order to repair or replace the rubber suction connecting piece 20 a pintle 21 can be pushed from the ship's hull into the ladder 8. After this the suction piece is disconnected and the ladder is lowered at the front.
Important advantages of the described pump ladder con-struction are:
a. a minimum weight is applied on the suction head;
b~ the operational period can be extended due to the fact that the operation of the pump ladder, installed in the well amidships, is not affected by ice on the water surface alongside;
c. when the suction head hits an obstacle such as a boulder, the suction head will not be damaged or lost, but will be lifted vertically over the boulder and the ship will sustain its speed;
d. the correct angular position of the suction pipe as well as the pressure of the suction head on the bottom can be main-tained;
e. lateral motion of the suction head can be better controlled;
f. the pumps can be installed on the pump in an improved manner; and g. all repairs to pumps, winches, wires, suction head - .
3Q~
etc. can be carried out inside the ship and working in open air can be avoided.
Finally it is remarked that no restrictive meaning should be attached to what is herein proposed, as still other embodiments are possible within the scope of the claims.
, ........... . .
,' ' , ~
.
This invention relates to a suction hopper dredger which is adapted to operate at great depths.
The present invention provides a suction hopper dredger, comprising a ladder, a suction tube which is carried on the end of the ladder, a pump arranged on the ladder, winch-operated tackles for the ladder and the suction tube, for one or more of which tackles a constant tension winch is to be used, and a well in which the assembly of ladder and suction tube is to be received, wherein the suction tube is pivotally connected to the ladder end and is positioned in the longitudinal direction opposed to the ladder, with the suction tube tackle being reeved on the ladder so that an upper part thereof extends from the suction tube winch to a pulley block on the ladder end, an intermediate part extends from said pulley block to a second pulley block which is arranged higher on the ladder, and a lower part extends from said second pulley block to the suction tube end, said upper and lower parts running downwardly substantiaily parallel to each other.
The manner of reeving the suction tube tackle on the ladder ensures that the motions of the respective tackles of the ladder and the suction tube are decoupled, whereby the positioning of the suction head is controllable in a more positive manner.
The invention is hereinafter first compared to another, less favourable way of outrigging the suction head and is further described in more detail in view of an embodiment thereof as represented in the accompanying drawings, wherein:-Figures 1 and 2 are side views of a dredger vessel illustrating a prior art arrangement of a suction hopper;
,.,j Figure 3 is a somewhat schematic side view of a dredger .
;
- ~1 7~;~30~
vessel in accordance with the invention;
Figure 4 is a view similar to Figure 3 illustrating the successive positions of the suction hopper in passing over an obstacle;
Figures 5a and 5b illustrate the suction hopper retractea within the dredger vessel;
Figures 6a and 6b illustrate the arrangement during repair of the suction head; and Figures 7a and 7b illustrate the arrangement of the suction hopper during replacement of the suction connection piece.
Figures 1 and 2 show for comparison another less favour-able way of tackling with hauled-in, and payed-out suction pipe-line, respectively; and figures 3-7 show a suction hopper dredger with the herein proposed novel suction pipeline carrying system.
The hopper dredger as illustrated in figures 1 and 2 has the disadvantage that the deflection of the suction head 6 which is carried on the end of the suction pipeline 1 is experienced in an augmented manner as the sum of the deflections of each of the articulated pipeline sections and is thus difficult to be con-trolled in a positive manner.
Disadvantages of the system suction pipes 1:
a. the suction pipe must be lowered alongside the hull, and to avoid that the soil must be transported higher than the water level to the pump 2; for this reason, in deep water, a special pump 4 must be installed in the suction pipe 1, which requires a pipe of heavy construction;
b. the water resistance 5 caused by the speed of the vessel, produces a pressure on the pipe l; to compensate this , : , .. .
11~783~
pressure a very heavy weight must be mounted to the suction head 6;
c. all forces must be borne by specially constructed hinging, heave compensated shear legs 7;
d. operating this type of ship in ice-sea conditions, with the outwardly protruding suction pipe and hoisting lines, is asking for trouble when also working in areas with ice-floes;
e. repairs to the suction head, shear legs and flexible hoses must be carried out in the open air.
DESCRIPTION OF THE PRINCIPLE
The pump ladder 8 on which the pumps 9 are arranged is carried and manoeuvred, as illustrated in figure 3, by a constant tension winch 10 preferably with heave-~ompensator. In its upper-most or retracted position the ladder 8 is contained in a well amidships as illustrated in the drawings.
When lowering the ladder 8 to a deep bottom 16, the wire length 11 from the ladder winch 10 increases. The wire 13 carrying the suction head 14 is reeved on the ladder 8 and its hoisting part 12 is controlled by the suction head winch 15. With the suction head winch 15 stopped and the ladder 8 moving up and down at con-stant tension, the suction head 14 will retain its position on the deep bottom 16.
When the suction bottom depth 16 is decreased, as indi-cated by 17, the influence of the movement of the pump ladder 8 on the suction head 14 will increase. This can be compensated by removing or adding tackle parts 13a, 13b of the suction head wire 13 as illustrated in figure 3.
THE WORKING PRINCIPLE OF THE HOPPER LADDER
When the suction head 14 meets an obstacle, as illus-~ : .
., : ' . ' :
, i ~L11 7~3(3~
trated in figure 4~the constant tension winch 10 will release wire 11 due to the fact that the ladder 8 will be pulled astern by the suction head 1~.
As the hoisting wire 11 of the ladder 8 increases in length, the length of the hoisting wire 12 of the suction head 14 will automatically also increase. Consequently the wire 13 decreases in length and will lift the suction head 14.
In the position as per c, the suction head will again reach the soil and the ladder 8 will tend to reposition itself and recover its position at d, as figure 4 illustrates.
This recovery of position will not have any influence on the position of the ship in view of the ship's mass of 45,000 tons moving continuously, in figure 4 the positions a, b, c, d of the suction head 14 correspond with the positions a, b, c and d of the ship in its onward motion.
In figures 5a and 5b is illustrated that above the pump, underneath the wheel house, a pump-repair-shop is arranged. The pumps for this ship will have a total weight of 30 to 50 tons, with separate parts of the pumps weighing about 15 tons. When the pump 9 must be replaced, this can be done by lowering the pump ladder, as in figure 5b, connecting the pump to special hooks on rails and bringing the ladder again underneath the new replacement pump 18 to install it~ This system will save considerable working time.
In a later stage the pump 1~ can be repaired and made ready for reinstallation.
The advantage of this system is the fact that no work has to be carried out in the open air.
Figures 6a and 6b illustrate that when repair of the ~.
, 33~3~
suction head 14 has to be carried out, a specially constructed repair pontoon 14b can be brought into position underneath the suction head, by rails 14c. Now the suction head can be repaired or replaced. The suction head can be transported into a repair shop 19 and repaired inside the vessel.
Figures 7a and 7b illustrate that to turn the pump ladder in order to repair or replace the rubber suction connecting piece 20 a pintle 21 can be pushed from the ship's hull into the ladder 8. After this the suction piece is disconnected and the ladder is lowered at the front.
Important advantages of the described pump ladder con-struction are:
a. a minimum weight is applied on the suction head;
b~ the operational period can be extended due to the fact that the operation of the pump ladder, installed in the well amidships, is not affected by ice on the water surface alongside;
c. when the suction head hits an obstacle such as a boulder, the suction head will not be damaged or lost, but will be lifted vertically over the boulder and the ship will sustain its speed;
d. the correct angular position of the suction pipe as well as the pressure of the suction head on the bottom can be main-tained;
e. lateral motion of the suction head can be better controlled;
f. the pumps can be installed on the pump in an improved manner; and g. all repairs to pumps, winches, wires, suction head - .
3Q~
etc. can be carried out inside the ship and working in open air can be avoided.
Finally it is remarked that no restrictive meaning should be attached to what is herein proposed, as still other embodiments are possible within the scope of the claims.
, ........... . .
,' ' , ~
.
Claims
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A suction hopper dredger, comprising a ladder, a suction tube which is carried on the end of the ladder, a pump arranged on the ladder, winch-operated tackles for the ladder and the suction tube, for one or more of which tackles a constant tension winch is to be used, and a well in which the assembly of ladder and suction tube is to be received, wherein the suction tube is pivotally con-nected to the ladder end and is positioned in the longitudinal direction opposed to the ladder, with the suction tube tackle being reeved on the ladder so that an upper part thereof extends from the suction tube winch to a pulley block on the ladder end, an intermediate part extends from said pulley block to a second pulley block which is arranged higher on the ladder, and a lower part extends from said second pulley block to the suction tube end, said upper and lower parts running downwardly substantially parallel to each other.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NL8103485A NL8103485A (en) | 1981-07-23 | 1981-07-23 | HOPPER PISTON. |
| NL8103485 | 1981-07-23 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1178301A true CA1178301A (en) | 1984-11-20 |
Family
ID=19837839
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000407859A Expired CA1178301A (en) | 1981-07-23 | 1982-07-22 | Suction hopper dredger |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JPS5891236A (en) |
| CA (1) | CA1178301A (en) |
| FI (1) | FI822578L (en) |
| NL (1) | NL8103485A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2639359A1 (en) * | 2012-03-16 | 2013-09-18 | Ondernemingen Jan De Nul, naamloze vennootschap | Dredging equipment and method for dredging or mining with such equipment |
| WO2015050445A3 (en) * | 2013-10-01 | 2015-06-25 | Baggermaatschappij Boskalis B.V. | Trailing dredging vessel with a dredging pipe |
-
1981
- 1981-07-23 NL NL8103485A patent/NL8103485A/en not_active Application Discontinuation
-
1982
- 1982-07-21 FI FI822578A patent/FI822578L/en not_active Application Discontinuation
- 1982-07-22 CA CA000407859A patent/CA1178301A/en not_active Expired
- 1982-07-23 JP JP12775682A patent/JPS5891236A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2639359A1 (en) * | 2012-03-16 | 2013-09-18 | Ondernemingen Jan De Nul, naamloze vennootschap | Dredging equipment and method for dredging or mining with such equipment |
| WO2015050445A3 (en) * | 2013-10-01 | 2015-06-25 | Baggermaatschappij Boskalis B.V. | Trailing dredging vessel with a dredging pipe |
Also Published As
| Publication number | Publication date |
|---|---|
| FI822578L (en) | 1983-01-24 |
| FI822578A0 (en) | 1982-07-21 |
| JPS5891236A (en) | 1983-05-31 |
| NL8103485A (en) | 1983-02-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6595494B1 (en) | Hoisting device, with compensator built into hoisting cable system | |
| CA2362875C (en) | Floating offshore construction, and floating element | |
| CN112627267B (en) | Buried plow and working method thereof | |
| GB2451545A (en) | Support for movement of well intervention, completion, testing, or drilling equipment | |
| US20100189513A1 (en) | Lay ramp actuating device and method for an underwater-pipeline laying vesse, and relative pipeline laying vessel | |
| US6718899B2 (en) | Method for installing a number of risers or tendons and vessel for carrying out said method | |
| US20020129755A1 (en) | Apparatus for and method of installing subsea components | |
| CN112600130A (en) | Embedded plough and working method thereof | |
| AU2005200784A1 (en) | Drag-head and hopper dredger | |
| US4345536A (en) | Vessel raising heavy structures | |
| CN103373446A (en) | Jacket removing ship and removing method | |
| CN110844003B (en) | Method for replacing mooring anchor legs by lifting double ships | |
| CA1178301A (en) | Suction hopper dredger | |
| CN2388170Y (en) | Floating base crane | |
| JP3332692B2 (en) | Elevated shear device for sand piles | |
| EP1129984A1 (en) | Apparatus and method for accessing a construction at sea | |
| CN112096312A (en) | Traveling block hook device for drilling ship or floating drilling platform | |
| US2924946A (en) | Submersible barge for off-shore drilling | |
| CN220743293U (en) | Marine fluid extraction system | |
| JPH0324936B2 (en) | ||
| CA1179299A (en) | Ship comprising one or more derricks such as a dredge with a suction pipe derricks | |
| WO2012060691A2 (en) | Dredging assembly | |
| CN218508216U (en) | Vehicle roll-on/roll-off channel arranged at wharf and with adjustable gradient | |
| JPS621040Y2 (en) | ||
| SU1062353A1 (en) | Pneumatic-hydraulic suction dredger |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEC | Expiry (correction) | ||
| MKEX | Expiry |