JPS584134B2 - Dredging method and cut-head suction dredger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dredging method using a cut-head dredger and the dredger.

In this type of dredging method, a cutter head with a suction nozzle designed to break down the soil is connected to the floating hull in a variable height manner, and side ropes are sent out from winches on the left and starboard sides of the dredger. In addition to moving back and forth by
A method of dredging by the operation of a cut-head suction dredger which is moored on a fixed trajectory, the dredging comprising: at least one longitudinal rope sent out from a winch on the bow side of the floating vessel and moored to the ground; The floating hull reciprocates laterally while being guided so as to be maintained by at least one longitudinal rope sent out from a winch on the stern side of the floating hull and anchored to the ground. The longitudinal ropes are wound by the mooring means during the reciprocating movement of the floating vessel, and the movement of the floating vessel in the longitudinal direction of the ground allows one longitudinal rope to be let out and the other longitudinal rope to be pulled in. There are some that are designed to be controlled by

Such a method is known from US Pat. No. 3,350,798.

This known method has the disadvantage that the cutter head cannot be precisely controlled due to the undefined slack and stretch of the longitudinal cable.

In order to carry out efficient dredging operations, it is important that the fixed start position of the cutter head be accurate during the reciprocating movement of the vessel, so mooring the cutter head dredger with cables during dredging is rarely practical. I couldn't do it.

Traditionally, cutterhead suction dredgers are mainly moored by spud piles to provide a fixed connection between the cutterhead and a fixed point, but when dredging at deep water points, Spanned piles must be heavy, and mooring with spanned piles is expensive for dredging operations in fluid waters, and even connections with variable water levels between the floating hull and the spanned piles do not work. , the movement radius around the spanned pile is limited to a relatively small radius.

Therefore, dredging operations often had to be interrupted to change the span pile position.

The invention aims to improve the control of the cutter head and reduce the number of interruptions during dredging operations.

To this end, the method of the invention includes measuring and detecting the tension in at least one of the two longitudinal ropes, while measuring and detecting the tension in at least one of the two longitudinal ropes.
The two rope winches are driven according to the measured one longitudinal rope tension.

The present invention further provides a cutter head suction dredger for carrying out the method of the invention, comprising at least one floating hull, a cutter head connected to the floating hull in a variable height manner, a pump, and provided near the canterhead, The suction nozzle is connected to the pump via the suction pipe, the side ropes are sent out from winches on both sides of the cutterhead dredger and moored to the ground, and the winches on the bow side of the floating hull are sent out and the ropes are sent out from the winches on both sides of the cutterhead dredger. and at least one longitudinal rope delivered from a winch on the stern side of the floating hull and moored to the ground, wherein the dredger has two longitudinal ropes. A cut-head suction dredger is provided, comprising a tension meter for measuring the tension of at least one of the ropes, and control means for driving at least one longitudinal rope winch according to the measurement result of the tension meter.

The above aspects as well as further detailed aspects of the invention will become apparent from the following description with reference to the accompanying drawings.

In the accompanying drawings, FIG. 1 is a plan view showing a preferred embodiment of the cutter head suction dredger according to the present invention, FIG. 2 is an enlarged view showing the portion II in FIG. 1 in detail, and FIG. Figure 1 is a side view of the cutter head type suction dredger, Figure 4 is a detailed view of the modification of the section ■ in Figure 3, and Figure 5 is a schematic diagram showing the winch control section of the cutter head type suction dredger in Figure 1. 6 is a plan view showing another modification of the cutter head type suction dredger according to the present invention, and FIG. 7 is a detailed view of the modified example of the section ■ in FIG. 5 for the cutter head type suction dredger of FIG. 6. be.

A cutter head type suction dredger 60 shown in FIGS. 1 to 3, which is a specific example of carrying out the method of the present invention, has a floating hull 1 and a motor 71 connected to the floating hull 1 so that its height can be adjusted.
a cutter head 3 rotatably driven by a ladder 2 connected to a floating hull 1 and configured to be rotatable about a horizontal axis 61; a pump 62 disposed near the cutter head 3; A suction nozzle 64 communicating with the pump 62 via a pipe 63, a flotation pressure pipe 70 communicating with the pump 62, and winches 30 on both port and starboard sides 65 and 66 of the cantahend suction dredger 60.
, 29 and 25, 19, respectively, and are anchored to the ground 67 by anchors.
and 13, a vertical rope 6 (hereinafter referred to as the bow rope 6) extending from the bow 68 of the floating hull 1 and the bow winch 16 and moored to the ground 67 by an anchor.

), and a longitudinal rope 8 (hereinafter referred to as stern rope 8) which is provided at the stern 44 of the floating hull 1, extends from a winch 69, and is moored to the ground 67 by an anchor.

).

The above side ropes 10, 12, 11 and 13 are connected to the anchor 14
The vertical ropes 6 and 8 are fixed to the ground 67 by anchors 7 and 9, respectively.

The cutter head type suction dredger 60 according to the present invention includes a tension gauge 18 provided on the stern rope 8 to measure the tension of the stern rope 8, and a control mechanism for the stern winch 16 of the stern rope 6 controlled by the tension gauge 18. It is characterized by:

As is clear from FIG. 1, the cutterhead dredger 60 is reciprocated along the path beyond the cutting depth a by means of the side ropes 10, 11, 12 and 13.

The floating hull 1 swings around the anchor 9 of the stern rope 8.

The broken line shows a state in which the cutter head dredger 60 has rotated around the anchor 9 to a different position.

FIG. 2 shows the controls for winches 16, 69, 30, 29, 25 and 19.

According to the method of the invention, the cut-head dredger 60 is displaced along an arc of constant radius R centered on the anchor 9 by the stern rope 8 which is kept the same length or substantially the same length. Therefore, the bow rope 6 is connected to the tension gauge 1.
It is paid out in response to the tension measured by 8,
I get pulled in.

If this swing radius R is increased stepwise by the value a, then during each swing stroke the excavation depth will be equal to or substantially equal to said value a.

This is extremely important for the cutter head dredger 60 to operate properly in order to make the thickness a of the excavated portion of the land uniform.

By moving the side ropes 12 and 10 in and out, respectively, so that the cutter head 3 is moved along the trajectory b by the side ropes, a drive signal is sent to the frontmost side rope winch 29 via the control device 31. and 30 controllers 21
and 28 are applied.

The control device 31 sends signals via the computing device 22 to the controllers 23, 20 of the rearmost side rope winches 25 and 19 for unwinding or retracting these side ropes 11 and 13.

According to the position of the ropes 10, 11.12 and 13, the winches 29 and 30 move in and out proportionally, depending on the difference in distance from the anchor 9 of the lateral ropes 10, 12 and lateral rope = 11.13. A low voltage is supplied so that the winches 25 and 19 pay out and pull in a short length of rope.

The angle meter 21 measures the angle d between the surface 72 of the floating hull 1 and the stern rope 8, and this measured value is supplied to the calculation device 22.

Since the stern rope 8 must be kept in the closest position to the plane 72, the signal of the measured angle d for controlling the controllers 23 and 20 of the winches 25 and 19 associated with the rearmost ropes 11 and 13 is Control device 3 within computing device 22
1 such that the stern rope 8 is held substantially unchanged on the adjusted surface 12.

Referring to the side view of FIG. 3, the anchor 9 is located relatively far from the floating hull 1.

A high tension is applied to the rope to ensure that the rope 8 hangs down between the floating boat 1 and the anchor 9 to such an extent that it does not touch the ground at all or hardly touches the ground.

Similar adjustments are made to the ropes 6.10, 11.12 and 13, the tension of which is controlled in the same manner as above to provide accurate positioning.

The anchoring means 38, shown in detail in FIG. A fixing ring 37 is provided.

This drop pile 36 is pulled up while being vertically guided in a guide tube 74 by a lifting device 73.

A pressure pipe 70 is conveniently extended through the float 39 to the desired work point, and the pipe 76 between the cut-head suction dredger 60 and the float 39 is highly flexible, while the pipe 76 aft of the float 39 Portion 71 may be substantially rigid.

According to the above-described embodiment of the method of the invention, when dredging a trench 81 having a width t (FIG. 1), anchors 1 and 9 are located substantially in the longitudinal midplane 80 of the trench 81. arranged,
The anchor 14 is installed on the side of the cutterhead dredger 60.

The cutterhead dredger 60 is moored at a starting position in the longitudinal center plane 80, and then the ropes 6, 8, 10, 11
．． 12 and 13 are tensioned at a predetermined tension, and the side rope 10
, 11, 12, 13 are winches 19, 25, 29, 30
The stern rope 8 is tensioned by the bow rope 6.

The cutter head dredger 60 is then moved to the working position shown by the solid line in FIG. 1, and when the ladder 2 is lowered together with the cutter head 3 to a predetermined depth, the first excavation 4 can be carried out.

The ropes 10 and 11 are slowly unwound, while the ropes 12 and 13 are drawn in at a rate imposed by the cut-head dredger 60 depending on the nature of the soil to be degraded.

During the complete swing, the tension in the stern rope 8 remains constant according to the value measured by the tension meter 18.

The measured value amplified by the amplifier 52 is displayed by the indicator 51 of the control panel 43, and the amplified measured value is supplied to the controller 11 via the lead wire 62.

This controller 11 provides a control signal to the bow winch 16 after comparing this measured value with the tension of the stern rope 8 adjusted by the setting device 48 .

A signal supplied from the controller 58 to the controller 31 of the front rope winches 29 and 30 is applied to the controller 28 of the front winch to pull in the rope 12 and is applied to the controller 21 of the front winch to cause the winch 30 The rope 10 is let out from the top and the residual tension is maintained.

The signal from the controller 58 on the panel 43 is the rear side winch 2.
5 and 19, the above-mentioned signal is also fed to the calculation device 22 for the rear rope winches 25 and 19.

A signal from the angle meter 21 amplified by an amplifier 55 is also applied to the calculation device 22 .

Depending on the position of the lever 56 of the angle meter 21, a signal sent from the computer 22 is supplied to the controller 20 of the winch 19 for pulling in the rope, and the canterhesod type dredger 6
0's rear end 44 is displaced to the right at the correct rate and is also fed to the controller 23 of the rear lateral rope winch 25, which pays out the rope 11 with a predetermined residual tension.

After the excavation section 4 is dredged, the cantahend dredger 60 moves forward by the cutting depth a by adjusting the setting device 59 of the control panel 43 to the length a.

The signal from the setting device 59 is applied to the controller 57 of a stern winch 69, which is driven with the aid of the switching knob 50 to pay out the rope 8 over a length a.

When the tension in the stern rope 8 disappears, it is detected by the tension meter 18, and this detection result is supplied to the ILJ controller 11 of the bow winch 16 via the amplifier 52, and
is immediately activated and the adjusted tension is again applied to the stern rope 8.

Since the controller 11 can respond very quickly, the stern rope 8
When the bow rope 6 is let out, the bow rope 6 is immediately retracted in order to maintain a constant tension on the stern rope 8.

Winch 69 further sends a signal indicating the length of stern rope 8 via amplifier 54 to indicator 53, as well as to controllers 49 of aft winches 25 and 19.

As soon as the stern rope 8' reaches such a length that it no longer swings relative to the anchor 9 without dragging the rope along the ground for an unnecessarily long length, the cutterhead dredger 60 is anchored by anchors 14, 7 and 9 and placed in a new position.

The setting device 75 drives the winch 69 of the stern rope 8. move.

The cassota head dredger 60 then moves to a new starting position.

By operating the cutter head dredger 60 according to the invention, the ground 67 is stripped along a horizontal layer 84 (FIG. 3), and the cutter head 3 is kept constant at a predetermined level.

In this way, dredging operations can be carried out with high efficiency.

To avoid overloading the bow rope 6 during rocking of the cutterhead dredger, the preferred embodiment of the cutterhead dredger 60 shown in FIG. Two bow ropes 48 and 45 are provided, each with a cooperating winch 46 and 41, and an anchor 78 located at a relatively greater distance than in the case of a single stern rope.
and 79 are provided.

If two bow ropes 48 and 45 (FIG. 6) are provided, the details of the mechanism (2) in FIG. 5 are constructed as shown in FIG.

The controller 11 of FIG. 7 is further operated by the deflection signal generator 42 of the compass 86, which controller 17 controls the winches 46 and 47.

The tension meter 18 is rotatably supported by, for example, two rollers 82 provided on a frame 83 and the frame 83.
An auxiliary frame 85 having two guide rollers 41 is provided.

The auxiliary frame 85 is connected to the frame 83 via a tension rod 33 equipped with a tension measuring device 32, such as a strain gauge.

[Brief explanation of the drawing]

In the accompanying drawings, FIG. 1 is a plan view showing a preferred embodiment of the cutter head suction dredger according to the present invention, FIG. 2 is an enlarged view showing the portion H in FIG. 1 in detail, and FIG. A side view of the cutter head type suction dredger shown in Figure 1, Figure 4 is a detailed view of the modification of the section ■ in Figure 3, and Figure 5 is a schematic diagram of the winch control section of the cutter head type suction dredger shown in Figure 1. , FIG. 6 is a plan view showing another modification of the cutterhead suction dredger according to the present invention, and FIG. 1 is a detailed view of the modification of section 2 in FIG. 5 for the cutterhead suction dredger of FIG. 6. 1... Floating hull, 6... Bow rope, 7... Anchor, 8
... Stern rope, 9 ... Anchor, 10, 11, 12, 1
3... Side rope, 14... Anchor, 16... Bow winch, 18... Tension meter, 19... Winch, 20
...Control panel, 21...Angle meter, 22...Calculating device, 23...Controller, 25...Winch, 27...
Controller, 29... Winch, 30... Winch, 3
DESCRIPTION OF SYMBOLS 1... Control device, 36... Dropping pile, 37... Fixing ring, 38... Anchoring means, 39... Float, 4
4... Rear end (of the ship), 49... Pull-in ratio adapter, 60... Cutter head type suction dredger, 61...
・Horizontal axis, 65...Port side, 66...Starboard side, 6
7... Ground, 68... Bow, 70... Floating pressure pipe, 71... Motor, 73... Lifting device.

Claims (1)

[Scope of Claims] 1. A cassota head having a suction nozzle and adapted to decompose soil is connected to the floating hull in a variable height manner, and side ropes are sent out from winches on the left and starboard sides of the dredger. A method of dredging by the operation of a canterhesod suction dredger, which moves reciprocatingly and is moored on a fixed trajectory, the dredging being carried out from a winch on the bow side of the floating vessel and at least one dredger moored to the ground. The floating hull is moved laterally while the floating hull is maintained and guided by the main longitudinal ropes and at least one longitudinal rope delivered from a winch on the stern side of the floating hull and anchored to the ground. This longitudinal rope is wound by the mooring means during the reciprocating movement of the floating vessel, and the movement of the floating vessel in the longitudinal direction of the ground causes one longitudinal rope to be paid out and the other In the dredging method, the tension of at least one of the two longitudinal ropes is measured, and the tension of at least one of the longitudinal ropes is controlled by pulling in the tension of the longitudinal rope. A dredging method characterized by responding depending on the 2. The dredging method according to claim 1, wherein the winch on the other longitudinal rope is driven in accordance with the tension measured on one longitudinal rope. 3. The dredging method according to claim 1 or 2, wherein one longitudinal rope is a stern rope. 4. The dredging method according to any one of Claims 1, 2, and 3, in which the cantahend-type suction dredger swings on an arc centered on the mooring point of a stern rope of a certain length. . 5. The dredging method according to any one of the preceding claims, wherein the floating hull is maintained by at least two bow ropes sent out from a winch on the bow side and moored to the bottom land. 6. A dredging method according to any of the preceding claims, wherein the angle between the floating hull and one longitudinal rope is measured, and at least one winch of the rope is adjusted according to the measured angular position. Dredging method in which the dredging is driven by 7. The dredging method according to claim 6, wherein the winch is driven so that the angular position is substantially constant. 8 A katsutahend-type suction dredger that implements the method according to any of the above claims, comprising at least one floating hull, a katsutahend connected to the floating hull in a variable height manner, a pump, and a katsuta hend. A suction nozzle installed near the ship and connected to the pump via a suction pipe, side ropes sent out from winches on both port and starboard sides of the Katsutahend dredger and moored to the ground, and a winch on the bow side of the floating hull. and at least one longitudinal rope delivered from a winch on the stern side of the floating hull and moored to the ground; A cutterhead suction dredger, characterized in that it is equipped with a tension meter for measuring the tension of at least one of the directional ropes, and means for controlling at least one winch of the longitudinal ropes according to the measurement results of the tension meter. . 9. The dredger according to claim 8, wherein a tension meter is provided on one of the two longitudinal ropes, and a winch control means for the other rope is responsive to the tension meter. 10. The dredger according to claim 8 or 9, wherein the tension gauge is provided on the stern rope. 11. A dredger according to claim 8, 9 or 10, which has two bow ropes. 12. A dredger according to claims 8 to 11, including an angular position detector that measures the angular position of the floating hull with respect to one longitudinal rope, and the angular position detector measures the angular position of the floating hull with respect to one longitudinal rope. Dredger controlling said at least lateral rope winch to modify. 13. The dredger according to any one of claims 8 to 12, comprising: one float on at least one of the two longitudinal ropes; and a drop pile connected to the float by a lifting means; A dredger is provided with an anchoring means having a connecting means for fixing a vertical rope of the cutterhead dredger to a dropping pile. 14 In the dredger described in claim 13,
A dredger in which a pressure pipe extends from a pump in the floating hull through the float.