JP3881868B2 - How to lay pipes under water - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method of laying pipes such as various pipes under water bottom ground such as rivers, seas and lakes.
[0002]
[Prior art]
When laying pipes such as various pipes under the bottom ground of rivers, seas, lakes, etc., (a) a pre-drilling method that excavates the bottom floor ground with a bucket ship before laying the pipe, (b) pipe After laying the body on the bottom of the ground, excavating after laying the existing pipe body by sinking the existing pipe body into the excavation groove by discharging the earth and sand around the existing pipe body to the side of the existing pipe body with a unit dredge equipped with jet nozzles Methods exist as prior art.
[0003]
[Problems to be solved by the invention]
However, when laying pipes under water bottom ground, first of all, it is required from the viewpoint of environmental protection to minimize the pollution generated in the working water area. In this respect, the prior art has a problem that a large amount of earth and sand diffuses in the working water area, so that the use thereof is restricted particularly when a fishing ground exists near the working water area.
[0004]
On the other hand, some submarine cables and oil / gas submarine pipes are excavated using a plow-type excavator around the existing pipes. Due to the complexity, the equipment cost is high, and since the operation is complicated, it is uneconomical when applied to a relatively shallow water depth. In addition, since the conventional plow excavator supports its own weight on the bottom of the ground, it cannot be applied when the bottom of the ground is soft.
[0005]
The present invention has been made to eliminate the above-mentioned drawbacks of the prior art. In particular, it can prevent contamination of surrounding water areas due to work, can be constructed even if the bottom of the ground is soft, and has a simple and efficient configuration. The object is to provide a method for laying pipes under water bottom ground.
[0006]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention provides the following method for laying a pipe body under water bottom ground.
(A) the first invention, forward has a plow, and the plow-type excavator backward tube tip is connected to the plow, work boat or al height adjustable suspended by a plurality of hanging again and again from the suspended water, land, and excavating the sea bed soil by pulling the pulling force from the water or water bottom fixed point drilling grooves formed in the sea bed locations Release, the plow to the drilling groove a tube laying method for laying set the tube to be coupled to the formula excavator during excavation of the sea bed soil, by adjusting the length of the hanger, the bottom position of the plow excavator The posture of the plow excavator is controlled so as to be the planned excavation position of the water bottom ground, and the weight of the plow excavator is supported by the lifting tool .
(B) a second invention, in a state where the lower end of the digging edge is inclined so as to approach, the plow-type excavator digging edge of two to the apparatus bottom surface is mounted one pair to face, from work ship height adjustable suspended by hanging a plurality of hanging again and again from the water, on land, the plow excavator towed along the existing pipe member by traction from water or water bottom fixed point, of the existing pipe member the excavation is formed in the sea bed locations Release drilled earth and sand sides or bottom or side surface and the bottom surface, a tube laying method to precipitate the existing pipe body excavation groove, during drilling, the length of the hanging member By adjusting the height, the plow drilling is performed so that the existing pipe body on the water bottom ground is positioned between the drilling blades, and the lower end of the drilling blade of the plow drilling machine is a planned drilling position below the bottom of the water surface. Control the attitude of the machine, and the weight of the plow excavator It is supported by hanging tools .
At this time, the two digging edge provided on the lower side of the plow excavator and tiltable excavator width direction, to allow placing the digging edge lower end to the existing tube under side sea bed locations inside the panel of Is preferred.
(C) A third invention is two drilling blades arranged in parallel on the device bottom, and the tube under the sea bed soil with excavator capable of changing intervals of the digging edge Mutual is the opening-and-closing a method of laying in a state of closing the digging edge, said excavating machine hanging from the water again and again hanging plurality that is suspended to allow height adjustment of the working ship, the length of the hanging member A first step of controlling the attitude of the excavator by adjusting, and placing the lower end of the excavator at the planned excavation position below the bottom of the water while supporting the weight of the excavator with the lifting tool ; said spread perpendicularly spacing of the digging edge of the self-weight of the excavator while supported by the hanging member against the tube laying direction, a second step of forming a drilling groove on the sea bed locations Release, wherein After closing the excavating blade, the work is continued while the weight of the excavator is supported by the hoisting tool. And a third step of moving the ship to the tube laying direction, the first to third step is extending the excavation by repeating Succoth in this order, wherein after drilling the same time or drilling completion characterized by laying the pipe body drilling groove.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
<First Embodiment>
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram of a first embodiment of the present invention. 1st Embodiment connects the front-end | tip of the pipe body 2 to the back of the plow-type excavator 1, and pulls the plow-type excavator 1 and forms the excavation groove 4 in the water bottom ground 3, and the pipe body 2 is made into an excavation groove. 4 to be laid.
[0008]
2 and 3 are views showing the plow excavator 1 used in the first embodiment. The plow excavator 1 is provided on a substantially V-shaped plow body 5 that spreads from the front to the rear. A bottom plate 6, a reaction force body 7, and a support rack 8 are attached. In addition, when the weight of the plow excavator 1 is insufficient, the reaction force body 7 may also serve as a weight.
[0009]
The lower surface of the front surface of the plow body 5 is inclined at an acute angle with respect to the bottom surface, and this inclination angle spreads so as to approach vertically from the front to the rear of the plow body 5. Edges for earth and sand excavation are formed at the leading inclined portion and the lower end portion of the plow body 5. Further, the inclined surface in the vicinity of the top portion of the plow body 5 is gently curved in an inward bow shape, and when the plow excavator 1 is pulled, the plow excavator 1 is pushed down by the earth pressure resistance applied to the curved surface. It is like that. A puller wire connecting portion 5 a is provided above the top inclined portion of the plow body 5.
[0010]
A bottom plate 6 is fixed to the back surface of the plow body 5 along the lower end of the plow body 5. A reaction force body 7 that pulls the tube body 2 is provided on the bottom plate 6, and the reaction force body 7 is provided with a tube connection portion 7 a toward the rear of the plow body 5. On the other hand, two support racks 8 are attached to the upper portion of the plow main body 5 at intervals with the plow main body 5 extending in the width direction. At both ends of the upper surface of the support rack 8, suspension connecting portions 8 a are provided.
[0011]
Here, the tube laying method of the first embodiment will be described in order.
(A1) The rope-equipped suspension 11 having one end fixed to the winch 10 on the work boat 9 is coupled to a plurality of suspension coupling portions 8a provided in the plow excavator 1, respectively. Then, the plow excavator 1 is suspended from the work boat 9 to the underwater 12 by a plurality of suspension tools 11 with ropes.
At this time, the tip of the pipe body 2 to be laid is connected to the pipe connecting portion 7a behind the plow excavator 1. A pulling wire 14 extending from a pipe laying winch 13 provided on land, on the water, or on the bottom of the water is connected to the pulling wire connecting portion 5a on the front surface of the plow excavator 1.
[0012]
(A2) Next, the plow-type excavator 1 is adjusted so that the bottom level of the plow-type excavator 1 becomes the planned excavation position of the submarine ground 3 while adjusting the rope length of the hoist with rope 11 with the winch 10 on the work boat 9. Set the excavator 1.
[0013]
(A3) Then, the pipe laying winch 13 is driven and the plow excavator 1 is pulled to excavate the water bottom ground 3. At this time, especially when the water bottom ground 3 is a sludge accumulation layer or a floating mud layer, the speed of excavation is adjusted to prevent scattering of earth and sand. In addition, the work boat 9 suspending the plow excavator 1 moves according to the traction of the plow excavator 1 and adjusts the rope length with the winch 10 on the work boat 9 to change the posture of the plow excavator 1. Play the role of controlling. The work boat 9 may be moved at the same speed as the plow excavator 1 (towing / self-propelled).
On the other hand, the pipe body 2 connected to the rear side of the plow excavator 1 is laid in an excavation groove 4 formed by pulling the plow excavator 1. The pipe body 2 laid in the excavation groove 4 is covered with natural sediment and buried under the bottom of the water. In addition, lengthening of the pipe body 2 laid is performed on the junction barge provided on the water or the land junction yard (illustration is abbreviate | omitted).
[0014]
Second Embodiment
Next, a second embodiment of the present invention will be described. In the second embodiment, earth and sand near the bottom of the existing pipe body 2a previously laid on the water bottom ground 3 is excavated by the plow-type excavator 20 to form the excavation groove 4, and the existing pipe body 2a is excavated in the four grooves. Is to be laid. In the following embodiments, the description of the same parts as in the previous examples is omitted.
[0015]
4 and 5 are diagrams showing a plow excavator 20 used in the second embodiment. The plow excavator 20 is configured by attaching two excavating blades 22 to the lower surface of a plurality (four in the figure) of support frames 21 extending in a direction orthogonal to the traveling direction. A suspension connecting portion 21a is provided on the upper surface of the leading and rearmost support frames 21 with respect to the traveling direction. In addition, the leading support frame 21 with respect to the traveling direction is provided with a pulling wire connecting portion 21b at the center of the side surface in the traveling direction.
[0016]
The excavation blade 22 is formed in a substantially trapezoidal shape in which the side on the traveling direction side is curved in an inward arcuate shape, and the curved side is inclined at an acute angle with respect to the lower base. The whole is curving gently so that it will warp. Edges for earth and sand excavation are provided on the curved side portion and the lower base portion located on the traveling direction side of the excavating blade 22. In addition, a plurality of connecting pieces 22 a each having an insertion hole for the locking pin 23 are provided at the upper end of the excavating blade 22. Note that a pair of excavating blades having a line-symmetric relationship is used for the two excavating blades 22 of the second embodiment.
[0017]
The pair of excavating blades 22 is attached to the lower surface of the support frame 21 in a C-shape that spreads backward with the curved side portion at the top, with the curved surface convex portion of the excavating blade 22 facing inward. The pair of excavating blades 22 are attached to the support frame 21 in a state of being inclined so that the lower end of the excavating blade 22 approaches as viewed from the front of the apparatus and symmetrically with respect to the neutral axis. Further, the excavating blade 22 is pin-coupled to the support frame 21 by a locking pin 23 inserted through the connecting piece 22a.
[0018]
In addition, a fluid pressure cylinder 24 that connects the excavation blade 22 and the support frame 21 is provided inside the connecting portion of each excavation blade 22 with the support frame 21. As the fluid pressure cylinder 24 expands and contracts, the inclination angle between the support frame 21 and the excavation blade 22 can be adjusted.
[0019]
Here, the tube laying method of the second embodiment will be described in order.
(B1) First, the pipe body 2a is laid on the water bottom ground 3 by a known method such as a water bottom tow method, a floating tow method, a laying ship method or the like.
[0020]
(B2) The rope-equipped suspension 11 having one end fixed to the winch on the work boat is coupled to a plurality of suspension coupling portions 21 a provided in the plow excavator 20. Then, the plow excavator 20 is suspended from the work boat to the underwater 12 by the plurality of rope-equipped suspension tools 11. At this time, the pulling wire 14 extending from the pipe laying winch provided on land, on the water, or on the bottom of the water is connected to the pulling wire connecting portion 21b of the plow type excavator 20.
[0021]
(B3) Next, the existing tubular body 2a is positioned between the excavating blades 22 while adjusting the rope length of the hoist with rope 11 with the winch on the work boat, and the lower end of the excavating blade 22 is the existing tubular body 2a. The plow type excavator 20 is set so as to be disposed in the lower water bottom ground 3.
The plow-type excavator 20 is arranged such that the excavation blade 22 straddles the existing pipe 2 a in a state where the inclination angle of the excavation blade 22 with respect to the support frame 21 is increased by the extension of the fluid pressure cylinder 24. Thereafter, the fluid pressure cylinder 24 is contracted so that the inclination angle of the excavating blade 22 with respect to the support frame 21 is reduced, so that the lower end of the excavating blade 22 wraps around the lower side of the existing pipe 2a. In addition, when the water bottom ground is soft, the excavation blade 22 may be positioned only on the side of the existing pipe 2a.
[0022]
(B4) Then, the pipe laying winch provided on land, on the water or at the bottom is driven, and the plow excavator 20 is pulled along the existing pipe 2a. As shown in FIG. 5, the plow-type excavator 20 pulls the earth and sand near the bottom surface of the existing pipe body 2a to form the excavation groove 4 below the existing pipe body 2a. And the existing pipe 2a is laid in the excavation groove 4 because the existing pipe 2a sinks into the excavation groove 4 by its own weight. The work ship with the plow excavator 20 suspended moves according to the towing of the plow excavator 20, and controls the attitude of the plow excavator 20 by adjusting the rope length with the winch on the work ship. Fulfill.
[0023]
<Third Embodiment>
Next, a third embodiment of the present invention will be described. 6 and 7 are diagrams showing an excavator 30 used in the third embodiment of the present invention. The excavator 30 according to the third embodiment includes a support frame 31, a jack box 32, and two excavation blades 33.
[0024]
The support frame 31 is configured by fixing plate-like bodies 31b, which are stretched perpendicular to the pipe laying direction, to upper surfaces of both ends of two frame members 31a parallel to the pipe laying direction. The part is formed in the center. In addition, suspension attachment portions 31c are provided at the four corners of the upper part of the support frame.
[0025]
A jack box 32 is fixed to the upper part of the support frame 31 so as to cover the rectangular opening of the support frame 31. Inside the jack box 32, an excavation blade support beam 32a orthogonal to the pipe laying direction is installed. Further, a plurality of fluid pressure cylinders 32b extending and contracting in a direction orthogonal to the pipe laying direction are provided inside both side walls.
[0026]
The excavating blade 33 has a jack mounting portion 33b projecting from an upper portion of a rectangular excavating blade main body 33a that is long in the tube laying direction, and is formed in a substantially convex shape combining rectangles as a whole. The length of the excavating blade body 33a in the pipe laying direction is set to be approximately equal to the length of the frame member 31a. The vertical section of the excavating blade main body 33a has an inverted triangular shape that tapers toward the lower end, and an edge is formed at the lower end of the excavating blade main body 33a.
[0027]
The length of the jack mounting portion 33 b in the pipe laying direction is set slightly shorter than the length of the rectangular opening of the support frame 31. A mounting hole for the excavating blade support beam 32a is formed in the jack mounting portion 33b in the excavating blade width direction. In the third embodiment, two excavation blades 33 having the same shape are arranged so as to face each other.
[0028]
In the excavator 30 according to the third embodiment, two excavation blades 33 are arranged in parallel to the pipe laying direction below the support frame 31. The jack attachment portion 33 b of the excavating blade is disposed in the jack box 32 through the rectangular opening of the support frame 31. In the jack box 32, the excavation blade support beam 32a is inserted through the mounting holes of the two excavation blades 33. One end of a fluid pressure cylinder 32b is attached to the outside of the two excavation blades 33, respectively.
[0029]
That is, in the excavator 30 of the third embodiment, the excavating blade 33 moves back and forth in the direction perpendicular to the pipe laying according to the excavating blade support beam 32a by the expansion and contraction of the fluid pressure cylinder 32b located outside the excavating blade 33. The interval between the excavating blades 33 is opened and closed.
[0030]
Here, the tube laying method of the third embodiment will be described in order.
(C1) First, the rope-equipped suspension 11 having one end fixed to the winch on the work boat is coupled to the plurality of suspension-equipped coupling portions 31 c provided in the excavator 30. Then, the excavator 30 is suspended from the work boat to the underwater 12 by the plurality of rope-equipped suspension tools 11. On the other hand, a pulling wire 14 extending in advance from a pipe laying winch provided on land, on the water, or on the bottom of the water is stretched on the water bottom ground 3 in advance. The end of the pulling wire 14 is connected to the tip of the pipe body 2 to be laid.
[0031]
(C2) Next, with the winch 11 on the work boat adjusting the rope length of the rope-equipped suspension 11, the lower end of the excavating blade 33 is in the excavation position below the bottom ground 3 with the excavating blade 33 closed. The excavator 30 is set in At this time, the pulling wire 14 on the water bottom ground 3 is positioned between the two excavating blades 33 in the closed state [see FIG. 8B].
[0032]
(C3) Then, the excavation blade 33 is expanded in the direction perpendicular to the pipe laying to form the excavation groove 4 in the water bottom ground 3 [see FIG. 8 (c)]. Thereafter, the tubular body 2 is pulled into the excavation groove by towing the tow rope 14.
[0033]
(C4) Then, the work ship is moved in the tube laying direction, and the steps (C2) and (C3) are repeated. Thereby, the excavation groove 4 is extended in the pipe laying direction, and at the same time, the pipe body 2 is laid in the excavation groove 4. In the above example, excavation of the submarine ground and pull-in of the pipe body are performed at the same time, but after the excavator forms the excavation groove in the submarine ground, it is separately inserted into the excavation groove by a known method such as submarine towing method. A pipe body may be laid.
[0034]
In addition, the following matters are mentioned as modifications of the embodiment of the present invention described above. For example, when the water bottom ground is a sludge layer or a floating mud layer, there is a particular concern about the contamination of the working water area associated with excavation, and therefore, a scattering prevention net may be attached around the excavator.
[0035]
【The invention's effect】
Excavators used in the pipe laying method of the present invention are both simple and small, and are superior in cost compared to conventional unit dredgers and plows for seabed excavation. Moreover, the excavator is not only small, but also excavates the bottom ground by statically pushing out the bottom soil, etc., so that it is possible to minimize the scattering of sediment in the working water area. Excellent effect. In particular, when the bottom of the ground is a sludge layer or a floating mud layer, the effect is remarkable.
Furthermore, in the pipe laying method of the present invention, the excavator is suspended from the work boat to adjust the position with the bottom of the water, and the weight of the plow excavator is not supported on the bottom of the ground. It is possible to cope with various ground conditions.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of a first embodiment of the present invention.
FIG. 2 is a plan view and a side view of the plow excavator used in the first embodiment.
FIG. 3 is a perspective view of the plow excavator used in the first embodiment in use.
FIGS. 4A and 4B are a plan view and a side view of a plow-type excavator used in the second embodiment.
FIGS. 5A and 5B are a side view and a front view of the plow type excavator used in the second embodiment in use.
FIG. 6 is a perspective view of an excavator used in the third embodiment.
7A is a partially cutaway plan view of an excavator used in the third embodiment, and FIG. 7B is a cross-sectional view taken along line AA of FIG.
FIG. 8A is a side view showing a use state of the excavator of the third embodiment, and FIG. 8B is a front view of the excavator with the excavator blade closed; The figure is a front view of the excavator with the excavating blade open.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Plow type excavator 2 Pipe body 2a Existing pipe body 3 Submarine ground 4 Excavation groove 5 Plow main body 5a Tow wire connection part 6 Bottom plate 7 Reaction body 7a Connection part 8 for pipe body Supporting part 8a Connection part 9 for suspension equipment Work ship 10 Winch 11 Rope with rope (suspender)
DESCRIPTION OF SYMBOLS 12 Underwater 13 Tubing laying winch 14 Pulling wire 20 Plow type excavator 21 Support rack 21a Lifting tool connecting part 21b Pulling wire connecting part 22 Drilling blade 22a Connecting piece 23 Locking pin 24 Fluid pressure cylinder 30 Excavator 31 Supporting rack 31a Frame member 31b Plate-like body 31c Lifting tool connecting portion 32 Jack box 32a Excavation blade support beam 32b Fluid pressure cylinder 33 Excavation blade 33a Excavation blade body 33b Jack attachment portion

Claims (4)

It has a plow forward and backward pipe tip plow drilling motor connected is the plow, suspended in water by the height adjustably suspended by a plurality of hanger from work ship, land, and drilling the sea bed soil by pulling the pulling force from the water or water bottom fixed point drilling grooves formed in the sea bed soil to laying set the tube to be connected to the plow excavator to the drilling groove A pipe laying method,
During the excavation of the submarine ground, the posture of the plow excavator is controlled by adjusting the length of the lifting tool so that the bottom position of the plow excavator becomes the planned excavation position of the submarine ground. In addition, a pipe laying method under water bottom ground, wherein the weight of the plow excavator is supported by the lifting tool. In the lower end of the digging edge is inclined to approach a plurality of digging edge of two to the apparatus bottom surface a set attached plow excavator to face, is the height adjustable suspended from work ship The plow excavator is pulled along the existing pipe by the traction force from a fixed point on land, water or at the bottom of the water, and the side or bottom of the existing pipe or the soil on the side and bottom is removed. A pipe laying method in which excavation is performed to form a drilling groove in the bottom of the ground, and an existing pipe is submerged in the drilling groove ,
During excavation, by adjusting the length of the suspension tool, the existing pipe on the water bottom ground is located between the excavating blades, and the lower end of the excavating blade of the plow excavator is planned to be excavated below the bottom of the water surface. A method of laying a pipe body under a water bottom ground, wherein the posture of the plow excavator is controlled so as to be in a position, and the weight of the plow excavator is supported by the suspension tool. The two excavating blades provided on the lower side of the plow type excavator can be tilted in the excavator width direction, and the lower end of the excavating blade can be arranged in the water bottom ground below the existing pipe body. Item 3. A method of laying pipes under water bottom ground according to item 2. Two excavation blades are arranged in parallel on the lower side of the apparatus, and the pipe body is laid under the bottom of the ground using an excavator whose distance between the excavation blades can be changed by opening and closing movements ,
The digging edge in the closed state, the front SL excavator suspended in water by the height adjustably suspended by a plurality of hanger from work ship, the excavator by adjusting the length of the hanging member A first step of controlling the posture of the excavator and placing the lower end of the excavator at the planned excavation position below the bottom of the water while supporting the weight of the excavator with the lifting tool ;
Said spread perpendicularly spacing of the digging edge while supporting the weight of the excavator by the hanging member against the tube laying direction, a second step of forming a drilling groove in the sea bed soil,
A third step of moving the work ship in the pipe laying direction while supporting the own weight of the excavator with the lifting tool after closing the excavating blade ;
Said first through third step is extending the excavation by repeating Succoth in this order, to the sea bed soil under, characterized in that laying the pipe body to the drilling groove after drilling simultaneously with or drilling completion Tube laying method.

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