JPS63110326A - Operation controller for drag arm of drag suction dredger - Google Patents

Abstract

PURPOSE:To raise the efficiency of dredging operation by a method in which set input data on dredged soil quality are compared with suction negative pressure and input power of pump in the dredging condition, and when these do not agree with desired conditions, drag arm is raised to a proper condition. CONSTITUTION:Input power value for judging closed state, suction negative pressure, an optimal sludge content rate for dredging, corresponding input power value and suction negative pressure value, and input power value and suction negative pressure for judging the releasing of closed state are put from set value input unit 17 into an arithmetic unit 18. A sequence program of drag arm operation is also put in the unit 18. When dredging work is started, results from a suction negative pressure detector 15 and an input power detector 16 are compared with a set value for discriminating the closed state to judge whether it is closed. In the case of closing, a winch 5 is driven, and when the winding amount of the drag arm reaches a set value, it is judged whether it is low sludge content rate. In the case of low sludge content rate, the drag arm is stagewise rewound to discriminate whether it is proper sludge content rate.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a drag arm operation control device in a drag suction dredger.

[Prior Art] First, an outline of a drag suction dredger will be explained with reference to FIGS. 4 and 5.

Inside the dredger l, a pair of left and right dredging pumps 2. It is designed to be tilted by an arm winch 5°5. A drag head 6 is provided at the tip of the drag arm, and by operating the drag arm winch 5, the drag head 6 is brought into contact with the seabed 7 with a required ground pressure, and in this state, the dredger is advanced, and the drag head 6 touches the seabed 7. The dredging pump 2 sucks the earth and sand scraped from the ground together with seawater, and the mixture of earth and seawater is loaded into a mud hold 10 via a discharge pipe 8 and a loading trough 9 provided on the pump discharge side. .

Also, if the mud content of the mixture of earth and sand and seawater is below a predetermined value, the water is not loaded into the mud hold 10 and is directly discharged into the sea. This is done by switching the outboard discharge valve 13 provided on the outside discharge pipe 12.

During dredging work using such a dredger, if the seabed is soft mud like sludge, if the ground pressure is too thick, the drag head 6.6 will be buried in the sludge and suck the sludge directly, causing the discharge pipe to 8 or the drag arm 3 is blocked, making dredging impossible.

If dredging becomes impossible, the blockage must be resolved by actively suctioning seawater and diluting the muddy water.

Conventionally, the dredging suction line is blocked and unblocked as follows.

The first method is for an operator to visually monitor the flow of mud from the loading trough 9 to the mud hold 10 from the wheelhouse, determine that there is a blockage when the flow of mud has stopped, and manually control the drag arm winch. There is a method in which the drag head 6 is pulled out of the mud and seawater is sucked by operating the drag head 6.The second method is to provide an opening in the middle of the drag arm that is closed by a valve, and the opening and closing is done by the vacuum of the pump. This is determined by monitoring pressure, and when a blockage occurs, a valve is opened to bypass seawater and suck it out.

[Problems to be Solved by the Invention] However, in the first method, a worker must always monitor the dredging state, and the work to clear the blockage also relies on manual labor. Furthermore, the mud content in muddy water is greatly influenced by dredging efficiency, and the mud content is adjusted by the ground pressure of the drag head, etc., but the judgment of the mud content and the adjustment of the ground pressure are all based on the operator's intuition. Dredging efficiency is determined by the level of skill of the workers.

In addition, in the second method, an air cylinder is used as the actuator for opening and closing the valve, but the piping to the air cylinder must follow the movement of the drag head, making the piping process complicated. This is troublesome and requires additional work such as an air source due to the use of the air cylinder.

Furthermore, it is possible to use radiation to detect the mud content, but there are problems in that it is dangerous and difficult to control radiation.

In the method 1.2 above, when the mud content in the mud water is low, the suctioned mud water is discharged into the sea, but the switching of the valve is still performed directly by the operator.

In view of the above-mentioned circumstances, the present invention can prevent blockage of the dredging suction line without requiring operator supervision, can immediately eliminate blockage in the event of blockage, and further allows dredging work to be carried out at an optimal mud content ratio at all times. This is what we are trying to do.

[Means for Solving the Problems] The present invention provides a set value input section for setting and inputting data of dredging pump suction negative pressure and input power for mud content regarding dredged soil quality into a computing unit, and A detector that detects the input power of the dredging pump, a drag arm winch that hoists and lowers the drag arm, and a detector that compares the setting input data with the detection results from the rain detector and detects the content of suction mud water. In a drag suction dredger, the drag arm operation control device and the computing unit are equipped with the computing unit for driving the drag arm winch so that the mud ratio becomes an appropriate mud content ratio. a set value input section for setting and inputting input power data, a detector for detecting suction negative pressure of the dredging pump, a detector for detecting input power of the dredging pump, and a drag arm winch for hoisting and lowering the drag arm. , a hopper discharge valve that selectively discharges suctioned muddy water into the mud hold and the outboard side, a hopper discharge valve that discharges the outboard discharge valve, setting input data, and detection results from both of the above-mentioned detectors are compared to determine whether the muddy content of the suctioned muddy water is appropriate. It is characterized by comprising the arithmetic unit that drives the drag arm winch so that the mud content ratio is achieved, and opens and closes the hopper discharge valve and the outboard discharge valve depending on whether the mud content ratio is a low mud content ratio. This invention relates to a drag arm operation control device for a drag suction dredger.

[Function] Regarding the quality of dredged soil, compare the data obtained and set in advance with the suction negative pressure and input power of the pump in the dredging state, and judge whether the detected results match the desired state. ,
If they do not match, the drag arm winch is driven to raise and lower the drag arm so that it is in a proper state, and if the suction muddy water has a low mud content, the water is discharged overboard.

[Example] The present invention will be described in detail below based on the drawings.

In Fig. 1, 15 is a dredging pump suction negative pressure detector, 1B is a dredging pump input power detector, 17 is a set value input section, 18 is a calculator, 19 is an input/output processing section, 5 is a drag arm winch, and 13 is a 11 is a hopper discharge valve, 20 is an outboard discharge valve opening/closing detector, and 21 is a hopper discharge valve opening/closing detector.

First, based on experiments and actual results, the relationship between mud content and suction negative pressure for various soil types, and the suction negative pressure at the optimum dredging efficiency for each soil type are preset and input into the calculator 18 from the set value input section 17. I'll keep it.

Figure 2 shows a graph showing the relationship between the mud content rate, suction negative pressure, and input power for soft mud, which is an example of soil quality.
In the graph, region A indicates a low mud content, region B indicates a proper region, region C indicates a state close to blockage, and region D indicates a state of blockage.

Next, regarding the dredging area, the test excavation side investigates the soil quality of the dredging area, and based on the investigation results, the set value input section 17 selects the relevant soil quality from among the input data regarding the various soil properties.

When the dredging pump 2 is controlled at a constant speed, as shown in Fig. 2,
As the mud content increases, the suction negative pressure increases and the input power gradually decreases. However, when the suction line is close to or in a closed state, the suction negative pressure rapidly decreases and finally becomes positive pressure.

The decrease in input power is due to a decrease in flow rate due to an increase in mud content, and the rapid decrease in suction negative pressure is also due to a decrease in flow rate.

From the set value input section 17 to the arithmetic unit 18, the input power value for determining the blockage state, the suction negative pressure, the optimum mud content ratio for dredging, the input power value corresponding to the optimal mud content ratio, and the suction The negative pressure value, the input power value for determining whether the occlusion has been released, and the suction negative pressure are set and input, and a sequence program is input to operate the drag arm 3.

To illustrate the above setting input values in 22, during occlusion Inhalation negative pressure 100mmHg or less Input power 150KW or less Occlusion release Inhalation negative pressure 200mmHg or less 1130
nfflHg or more Input power 175KM or more Appropriate dredging conditions Mud content 15-50% suction negative pressure 20
0~600a+mHg Input power 175~l[f5KW Low mud content dredging Suction negative pressure 1130~200+nmHg
The input power is 175 or more than ν.

The sequence program described above is, for example, performed in three stages to raise the drag arm 3, and the suction negative pressure is checked at each stage.

Referring to FIG. 3, the flow of operations when dredging is performed under optimal conditions will be explained.

When dredging work is started, first, the detection results from the suction negative pressure detector 15 and the input power detector 16 are compared with the previous blockage state determination set value to determine whether or not there is a blockage.

If blockage is confirmed, the drag arm winch 5 is driven to hoist the drag arm 3 after a predetermined period of time has elapsed. The amount of winding of the drag arm is determined according to the amount set in the sequence program, and the amount of winding is determined based on the detection result from a wire lobe winding amount detector (not shown) provided on the drag arm winch 5. When the amount of hoisting reaches a set value, it is determined whether the mud content is low or not after a set time has elapsed. The detection results from the suction negative pressure detector 15 and the input power detector I6 are compared with the previous low mud content ratio condition, and if a low mud content ratio is not confirmed, the series of drag arm hoisting operations described above are repeated. will be returned.

If a low mud content rate is confirmed, that is, the blockage has been resolved, and the next step is to search for optimal dredging conditions.

The drag arm winch 5 is driven to lower the set amount.

The set lowering amount is a value obtained by dividing the set lifting amount described above into three equal parts, for example. Thus, it is determined whether or not the mud content is appropriate each time the winding is carried out one stage.

When it is determined that the mud content is appropriate, lowering of the drag arm 3 is stopped and dredging is performed.

Furthermore, the determination of the appropriate mud content rate is carried out as appropriate during the dredging work, and it is monitored to ensure that the dredging work is being performed in an appropriate state.

Further, if the mud content rate is determined to be low in the above-described determination of the blockage state, an operation to search for appropriate dredging conditions is immediately started.

Next, if blockage is not confirmed, opening/closing control of the hopper discharge valve 11 and the outboard discharge valve 13 is performed in accordance with the determination of low mud content and appropriate mud content.

First, it is determined whether the mud content is low or appropriate. If the mud content is appropriate, the hopper discharge valve 11 is opened and the outboard discharge valve 13 is closed. The outboard discharge valve 13 is opened and the hopper discharge valve 11 is closed, and the opening and closing movements of each valve are confirmed each time.

Therefore, dredging work is always carried out under appropriate conditions, and in the case of low mud content, it is reliably discharged overboard, so muddy water is not wasted.

[Effects of the Invention] As described above, according to the present invention, (1) Dredging can be performed under appropriate conditions at all times, so dredging efficiency is improved.

(ii) Even if a blockage occurs, the blockage is immediately cleared, reducing dredging work interruptions and improving the operating rate.

(To) Judgment of mud content and operation of the outboard discharge valve and hopper discharge valve do not rely on the intuition of the operator, so the accuracy is improved, and the efficiency of dredging work depends on the skill level of the operator. There is no.

(F) There is no need for workers to constantly monitor dredging work, resulting in labor savings.

It can exhibit excellent effects such as

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the concept of the configuration of the present invention, Fig. 2 is a graph showing an example of input data, Fig. 3 is a flowchart showing the work flow, and Fig. 4 is an overview of the dredging side. FIG. 5 is a front partial plan view of the same. 5 is a drag arm winch, 11 is a hopper discharge valve, 13
15 is a suction negative pressure detector, 16 is an input power detector, 17 is a set value input section, 18 is an arithmetic unit, and 19 is an input/output processing section.

Claims (1)

[Scope of Claims] 1) A set value input section for setting and inputting data of dredging pump suction negative pressure and input power with respect to mud content regarding dredged soil quality into a computing unit, and a detector for detecting dredging pump suction negative pressure. , the detector that detects the input power of the dredging pump, the drag arm winch that hoists and lowers the drag arm, and the setting input data and the detection results from both detectors are compared to determine whether the slurry content of the sucked muddy water is appropriate. 1. A drag arm operation control device for a drag suction dredger, comprising: the computing unit for driving a drag arm winch in such a manner that the drag arm winch is driven at a constant speed. 2) A set value input section for setting and inputting dredging pump suction negative pressure and input power data for mud content regarding dredged soil quality into a computing unit, a detector for detecting dredging pump suction negative pressure, and dredging pump input power. , a drag arm winch that raises and lowers the drag arm, a hopper discharge valve that selectively discharges sucked muddy water into the mud hold and the outboard side, an outboard discharge valve, setting input data, and detection of both of the above. Comparing the detection results from the device, the drag arm winch is driven so that the mud content of the sucked mud water becomes an appropriate mud content, and the hopper discharge valve is operated by determining whether or not the mud content is low. 1. A drag arm operation control device for a drag suction dredger, comprising: the computing unit for opening and closing an outboard discharge valve.