JPH0335451B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] 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 1, there are a pair of dredging pumps 2 on the left and right,
2, and drag arms 3, 3 are provided on both sides so as to be freely tiltable, and the drag arms 3, 3 are tilted by drag arm winches 5, 5 via wire ropes 4, 4. ing. A drag head 6 is provided at the tip of the drag arm,
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 moved forward, and the earth and sand scraped from the seabed 7 by the drag head 6 is removed together with seawater using the dredging pump 2. Suction and discharge pipe 8 provided on the pump discharge side
A mixture of earth and seawater is then loaded into a mud hold 10 via a loading trough 9.

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, but this is done through the hopper discharge valve 11 provided in the discharge pipe 8 and the gunwale. This is done by switching the outboard discharge valve 13 provided in the external discharge pipe 12.

During dredging work using such a dredger, when the seabed is soft mud like sludge, if the ground pressure is too large, the drag heads 6, 6 will be buried in the sludge and suck the sludge directly, and the discharge pipe 8 or is 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, unblocking of dredging suction lines has been carried out as follows.

The first method is for an operator from the wheelhouse to visually monitor the flow of mud from the loading trough 9 to the mud hold 10, and when the flow of mud has stopped, it is determined that there is a blockage, and the worker manually removes the mud. drag arm winch 5,
5, the drag head 6 is pulled out of the mud and seawater is sucked in.The second method is to have an opening in the middle of the drag arm that is closed by a valve, and the opening and closing is controlled by the vacuum pressure of the pump. This is determined by monitoring the system, 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 rate in muddy water is greatly influenced by dredging efficiency, and the mud content rate is adjusted by the ground pressure of the drag head, etc., but the judgment of the mud content rate and the adjustment of the ground pressure are all based on the intuition of the operator. 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 and troublesome. In addition, additional work is required due to the use of the air cylinder, such as an air source.

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 first and second methods, 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 even if a blockage occurs, and furthermore, can perform dredging work with 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 detector that detects the input power of the dredging pump, and a drag arm winch that hoists and lowers the drag arm. A drag arm operation control device in a drag suction dredger equipped with the computer unit that drives the drag arm winch so that the mud ratio becomes an appropriate mud content ratio, and a calculation unit that controls the dredging pump suction load with respect to the mud content ratio in relation to the quality of the dredged soil. A set value input section for setting and inputting pressure and 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 and an outboard discharge valve that selectively discharge sucked muddy water into the mud hold and the outboard side, and the setting input data and the detection results from both of the above-mentioned detectors are compared to determine the mud content rate of the sucked muddy water. the arithmetic unit that drives the drag arm winch so that the mud content becomes a proper mud content, and opens and closes the hopper discharge valve and the outboard discharge valve depending on whether the mud content is a low mud content. The present invention relates to a drag arm operation control device for a drag suction dredger, characterized by:

[Function] Regarding the quality of dredged soil, compare the data obtained and inputted in advance with the suction negative pressure and input power of the pump in the dredging state, and determine whether the detected result matches 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] Embodiments of the present invention will be described below based on the drawings.

15 in Figure 1 is the dredging pump suction negative pressure detector, 1
6 is a dredging pump input power detector, 17 is a set value input section, 18 is a computing unit, 19 is an input/output processing section, 5 is a drag arm winch, 13 is an outboard discharge valve, 11
is the hopper discharge valve, 20 is the outboard discharge valve opening/closing detector,
21 indicates a hopper discharge valve opening/closing detector.

First, based on experiments and 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 determined in the set value input section 1.
7, the settings are input to the computing unit 18 in advance. Second
The figure shows a graph showing the relationship between mud content, suction negative pressure, and input power for soft mud, which is an example of soil quality. Area A in the graph is low mud content, B is appropriate range,
Area C indicates a state close to occlusion, and area D indicates a state of occlusion.

Next, regarding the dredged area, test excavation is performed to investigate the soil quality of the dredged area, and the setting value input section 17 is set based on the investigation results.
The relevant soil type is selected from among the data regarding the various soil types inputted above.

When the dredging pump 2 is controlled at a constant speed, the suction negative pressure increases as the mud content increases, as shown in Figure 2.
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 calculator 18, input power values, suction negative pressure,
In addition, input the optimal mud content ratio for dredging, the input power value and suction negative pressure value corresponding to the optimal mud content ratio, and the input power value and suction negative pressure value for determining whether the blockage has been released. At the same time, a sequence program is input to operate the drag arm 3.

Here, as an example of the above setting input values, Negative suction pressure during occlusion: 100mmHg or less Input power 150kw or less Removal of occlusion Negative pressure inhalation 200mmHg or less 160mmHg or more Input power 175kw or more Appropriate dredging conditions Mud content 15-50% Inhalation negative pressure 200-600mmHg Input power 175~165kw Low mud content dredging Suction negative pressure 160~200mmHg Input power 175kw or more It is.

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 begins, the suction negative pressure detector 1
5. Compare the detection result from the input power detector 16 with the previous blockage state determination setting value to determine whether or not there is blockage.

If blockage is confirmed, the drag arm winch 5 is driven to wind up 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 rope 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. Suction negative pressure detector 15 and input power detector 16
The detection result from 1 is compared with the previous low mud content condition, and if a low mud content is not confirmed, the series of drag arm hoisting operations described above are repeated.

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, each time the winding is lowered by one level, it is determined whether or not the mud content is appropriate. Lowering of the drag arm 3 that is determined to have an appropriate mud content 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 no blockage is confirmed, opening/closing control of the hopper discharge valve 11 and the outboard discharge valve 13 is performed in conjunction with the determination of low mud content and appropriate mud content.

First, it is determined whether the mud content is low or appropriate, and 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 there is no wasteful loading of muddy water.

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

() Even if a blockage occurs, the blockage will be cleared immediately, reducing interruptions in dredging work and improving operating efficiency.

() Since the judgment of mud content and the operation of the outboard discharge valve and hopper discharge valve do not rely on the intuition of the worker, the accuracy is improved, and the efficiency of dredging work is no longer dependent on the skill level of the worker. Moreover, since the mud content is determined from two items: the dredging pump suction negative pressure and the input power without using radiation, there is no need to have a radiation supervisor, making it extremely safe.

() 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 drawings]

Figure 1 is a block diagram showing the concept of the configuration of the present invention, Figure 2 is a graph showing an example of input data, Figure 3 is a flowchart showing the flow of work, and Figure 4 is a diagram of the dredging side. FIG. 5 is a side view showing the outline, and FIG. 5 is a front partial plan view thereof. 5 is a drag arm winch, 11 is a hopper discharge valve, 13 is an outboard discharge valve, 15 is a suction negative pressure detector,
16 is an input power detector, 17 is a set value input section, 1
Reference numeral 8 indicates a computing unit, and reference numeral 19 indicates 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 for 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 are compared with the detection results from both of the above detectors to determine whether the slurry content of the sucked muddy water is appropriate. A drag arm operation control device for a drag suction dredger, characterized in that it is equipped with the arithmetic unit as described above for driving a drag arm winch in such a manner. 2. 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 calculator, a detector for detecting the dredging pump suction negative pressure, and input power for the dredging pump. A detector for detection, a drag arm winch for hoisting and lowering the drag arm, a hopper discharge valve and an outboard discharge valve for selectively discharging sucked mud water into the mud hold and the outboard side;
The setting input data is compared with the detection results from both of the detectors, and the drag arm winch is driven so that the mud content of the sucked mud water becomes an appropriate mud content, and whether or not the mud content is low. 1. A drag arm operation control device for a drag suction dredger, characterized in that said computing unit opens and closes a hopper discharge valve and an outboard discharge valve according to the judgment of the above.