JPH0311333B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an earth and sand pumping device.

[Conventional technology]

An example of this type of earth and sand pumping device will be explained with reference to FIG. This earth and sand pumping device has an earth and sand pump 1 such as a hose type, screw type, or piston type installed in an earth and sand storage tank 2.
Connect the earth and sand pumping pipe 3 to. An injection device 11 as a means for supplying a viscosity imparting agent (water, bentonite solution, etc.) 5 is provided at a location separate from the sediment storage tank 2.
, connect the base end of the injection pipe 9 to the injection device 11, and connect the injection port 1 at the tip of the injection pipe 9.
0 faces the upper opening of the earth and sand collection tank 2, and the injection device 11 and the earth and sand collection tank 2 are communicated with each other. The discharge side end of the conveyor 7 for transporting earth and sand is made to face the upper opening of the earth and sand storage tank 2.

Next, the operation of the above-mentioned earth and sand pumping device will be explained. First, the conveyor 7, the injection device 11, and the sand pressure pump 1 are operated. Then, the earth and sand 6 conveyed by the conveyor 7 is temporarily transferred to the earth and sand storage tank 2.
At the same time, the viscosity imparting agent 5 is injected into the sediment accumulation tank 2 from the injection device 11, and the sediment in the sediment accumulation tank 2 containing the viscosity imparting agent is pumped into the sediment displacement pipe 3 by the sediment displacement pump 1. The soil is discharged from the discharge port 4 of the soil pumping pipe 3 to the target location.

In such an earth and sand pumping device, the viscosity imparting agent 5
The most important thing is to convert the properties of the earth and sand 6 to be pumped by injecting an appropriate amount of sand into a property that can be pumped near the capacity of the earth and sand pump 1. In other words, if the properties of the earth and sand 6 to be pumped are too hard, the earth and sand 6
If the piping resistance becomes large and the piping resistance exceeds the capacity of the earth and sand pump 1, pumping becomes impossible. For this reason, it is necessary to soften the properties of the earth and sand 6, but on the other hand, if the properties of the earth and sand 6 are too soft, the earth and sand 6 will become muddy or muddy and become industrial waste, requiring complicated and troublesome post-treatment work. Is required. For this reason, there is a demand for hardening the properties of the earth and sand 6.
In this way, in order to satisfy the above-mentioned two conflicting conditions, that is, to convert the properties of the soil 6 into a property that does not require post-processing work and can be pumped within the capacity of the soil pump 1, Viscosifier 5
It is important to adjust the amount of injection.

Next, a conventional method for adjusting the injection amount of the viscosity imparting agent 5 will be explained.

(1) Adjust the injection amount of the viscosity imparting agent 5 while checking the properties of the earth and sand 6 discharged from the discharge port 4 of the earth and sand pumping pipe 3.

(2) Adjust the injection amount of the viscosity imparting agent 5 by estimating the load condition of the earth and sand pump 1, for example, the hydraulic pressure if the earth and sand pump 1 is hydraulically driven, or the current, etc. if it is electrically driven. do.

(3) Adjust the injection amount of the viscosity imparting agent 5 by checking the properties of the sediment 6 in the sediment storage tank 2.

[Problem to be solved by the invention]

However, the above adjustment method has the following problems.

The above-mentioned adjustment method (1) involves a time delay because the injection amount of the viscosity imparting agent 5 is adjusted by looking at the properties of the earth and sand 6 discharged from the discharge port 4 of the earth and sand pumping pipe 3. That is, it takes time for the earth and sand 6 in the earth and sand storage tank 2 to pass through the earth and sand pumping pipe 3 and be discharged from the discharge port 4 of the earth and sand pumping pipe 3. Therefore, when a certain earth and sand 6 is supplied into the earth and sand storage tank 2, and when the earth and sand 6 is supplied to the earth and sand pumping pipe 3,
There is a time difference (delay) between the time when the liquid is discharged from the discharge port 4 and the time when the liquid is discharged from the discharge port 4. As a result, if the properties of the earth and sand 6 discharged from the outlet 4 of the earth and sand pumping pipe 3 are different from those of the earth and sand 6 in the earth and sand storage tank 2, for example, the earth and sand discharged from the outlet 4 of the earth and sand pumping pipe 3 are different from each other. 6 is soft, and conversely, the earth and sand 6 in the earth and sand storage tank 2 is hard, and it is not possible to accurately inject the viscosity imparting agent 5 in an amount commensurate with the properties of the earth and sand 6 in the earth and sand storage tank 2. In particular, the longer the length of the earth and sand pumping pipe 3, the greater the time delay, and the above-mentioned drawbacks become more pronounced.

The adjustment method (2) above adjusts the injection amount of the viscosity imparting agent 5 by detecting the piping resistance over the entire length of the earth and sand pumping pipe 3, so the injection amount of the viscosity imparting agent 5 can be adjusted accurately. Can not do it. That is, since the piping resistance over the entire length of the earth and sand pumping pipe 3 is detected, earth and sand 6 having a certain property is being pumped. Sediment 6 with different properties in the earth and sand pumping pipe 3
Unless it enters a certain amount, it will not appear in the change in piping resistance. For example, the total length of the earth and sand pumping pipe 3 is
In the case of 100 m, if 5 m of earth and sand 6 that is harder and has greater piping resistance than that earth and sand 6 enters the earth and sand 6 that is being pumped into the earth and sand 6, the change in the detected value of the piping resistance will be 5 m. /100m, a change of only 1/20 appears, making it impossible to accurately detect the piping resistance and making it impossible to accurately adjust the injection amount of the viscosity imparting agent 5. Particularly in the case of hydraulic pressure, when the hydraulic pressure increases, the resistance of the seal part of the earth and sand displacement pump 1 increases and the initial resistance changes, and the back pressure changes due to the oil temperature and the hydraulic pressure changes, and the piping resistance increases due to other factors. Often influenced by factors. Therefore, a method can be considered in which the amount of viscosity imparting agent 5 to be injected is determined when the pipe resistance changes significantly, that is, when the detected value of pipe resistance is significantly affected. Since the soil must be introduced into the earth and sand pumping pipe 3 at the same time, it takes time for a large change to occur in the piping resistance, resulting in a time delay. Therefore, the same drawbacks as those of the adjustment method (1) described above occur. Furthermore, since it is necessary to put a large amount of earth and sand 6 of different properties into the earth and sand pumping pipe 3, for example, a large amount of earth and sand 6 that is hard in nature and has a large pipe resistance may be put into the earth and sand pumping pipe 3. If a sand pump 1 with sufficient capacity is not used, it will not be possible to pump the soil, and therefore a sand pump 1 with sufficient capacity must be installed, resulting in an increase in cost.

The above adjustment method (3) adjusts the amount of viscosity imparting agent 5 to be injected by looking at the properties of the sediment 6 in the sediment storage tank 2, so the operator does not have to go to the sediment storage tank 2. Therefore, it cannot be used in dangerous places such as narrow spaces or sites where methane gas is generated, and there is a problem that the range of use is greatly limited.

SUMMARY OF THE INVENTION An object of the present invention is to provide an earth and sand conveying device that improves the problems of the prior art as described above.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a means for detecting the frictional force between the pumped earth and the inner wall of the sand pumping pipe in the vicinity of the sand storage tank of the sand pump, and detects the friction force by the means. The present invention is characterized in that the amount of viscosity imparting agent to be injected can be adjusted by notifying the driver of the frictional force generated.

[Effect]

As described above, the present invention provides a means for detecting the frictional force between the earth and sand pumping pipe and the inner wall of the earth and sand pipe in the vicinity of the earth and sand storage tank, and notifies the driver of the frictional force detected by the detection means. As a result, the operator can know the properties of the sediment immediately after it is sent from the sediment tank to the sediment pumping pipe.
By adjusting the amount of viscosity imparting agent injected according to the frictional force, the excessive fluidity of the earth and sand is suppressed so that no post-processing work is required, and the earth and sand can be pumped by utilizing the capacity of the earth and sand pump. be able to.

〔Example〕

Hereinafter, a second embodiment of the earth and sand pumping device of the present invention will be described.
This will be explained with reference to FIGS. 5 to 5.

In the figure, the same reference symbols as in FIG. 1 are used.

Therefore, the earth and sand pumping device of the present invention in this embodiment includes a detector 8 near the earth and sand storage tank 2 of the earth and sand pumping pipe 3 for detecting the frictional force between the pumped earth and sand 6 and the inner wall of the earth and sand pumping pipe 3. In addition, an amplifier 12 is provided near the injection device operating section 11, and a meter 14 is provided near the injection device operation section 11.
4 and the amplifier 12 and between the amplifier and the detector 8, respectively. As shown in FIGS. 4 and 5, the detector 8 has a friction plate 17 mounted in a casing 80 of the detector via a flexible rod 20. That is, the casing 80 has a hollow cylindrical shape, and has a stepped portion 83 on its outer peripheral surface and a first stepped portion 8 on its inner peripheral surface.
1 and a second part 82 are provided. The first step portion 81
The base ends of three flexible rods 20 are planted at equal intervals,
A disk-shaped friction plate 17 is fixed to the tips of the three bending rods 20, and the friction plate 17 and the casing 8
A rubber packing 22 is interposed between the friction plate 17 and the end face of the casing 80 so that the surface of the friction plate 17 and the end face of the casing 80 are flush with each other. Further, a steel ball 19 is provided at the center of the inner surface of the friction plate 17, and a lid portion 21 is provided on the second step portion 82, and an arc-shaped detection plate 1 is provided on the lid portion 21.
8 is provided, and a steel ball 19 is brought into contact with the center of the detection plate 18. A strain gauge 16 is attached to the detection plate 18, and a cable 13 is connected to the strain gauge 16.
When a friction force is applied to the friction plate 17, the steel balls 19 receive the above-mentioned friction force and displace the detection plate 18, and the displacement (strain) is detected by the strain gauge 16, and the friction force 1 is detected by the strain gauge 16.
7 is configured to be able to detect the degree of frictional stress acting on it. The detector 8 thus formed is connected to the earth and sand pumping pipe 3.
In addition, the surface of the friction plate 17 and the inner wall surface of the earth and sand pumping pipe 3 are made flush, and the friction plate 17 and the earth and sand pumping pipe 3 are made of the same material and have the same surface roughness.

The earth and sand pumping device of the present invention has the above configuration, and its operation will be explained below.

When the earth and sand 6 are pumped into the earth and sand pumping pipe 3,
Since the earth and sand 6 normally have adhesive strength, it causes a plug flow within the earth and sand pumping pipe 3 over the entire cross section of the earth and sand pumping pipe 3, as shown by arrow A in Fig. It flows with a constant velocity distribution with slippage occurring between the two. At this time, a frictional force is generated between the earth and sand 6 and the inner wall of the earth and sand pumping pipe 3, and this frictional force acts on the friction plate 17 of the detector 8. As a result, the detector 8
Frictional stress is detected, and the detection signal is amplified by the amplifier 12 and sent to the meter 14. The driver 15 operates the injection device 11 while observing the value indicated on the meter 14 to adjust the injection amount of the viscosity imparting agent 5.

Here, the pressure loss ΔP caused by the frictional force between the inner wall of the earth and sand pumping pipe 3 and the earth and sand 6 is expressed by the following formula.

ΔP=π・D・L・P However, π: Pi D: Inner diameter of earth and sand pumping pipe 3 L: Length of earth and sand pumping pipe 3 P: Frictional stress In the above equation, pi, earth and sand pumping pipe Since the inner diameter D and length L of 3 are constant, if the frictional stress degree P is known, the pressure loss ΔP can be found. Since the viscosity imparting agent 5 is detected, the injection amount of the viscosity imparting agent 5 can be adjusted so that the large discharge pressure of the earth and sand pump 1≧pressure loss ΔP.

As described above, the earth and sand pumping device of the present invention can adjust the injection amount of the viscosity imparting agent 5 based on the friction stress P, that is, the pressure loss ΔP, immediately after entering the earth and sand pump 3 from the earth and sand storage tank 2. Therefore, the injection amount of the viscosity imparting agent 5 can be adjusted accurately, and therefore, the earth and sand 6 whose properties do not require post-processing work can be efficiently pumped. Moreover, since the degree of frictional stress P near the earth and sand storage tank 2 is detected, there is almost no time delay, and the injection amount of the viscosity imparting agent 5 can be adjusted as desired. Further, since the injection device 11 and the meter 14 can be installed apart from the sediment storage tank 2, they are not limited to the site of use. Furthermore, since the injection amount of the viscosity imparting agent 5 is accurately adjusted to obtain soil with desired properties, and the soil 6 is efficiently pumped, extra capacity of the soil pump 1 is not required, and the soil 6 is efficiently pumped. It is sufficient to equip a sand pump with a capacity commensurate with the capacity for good pressure feeding, and the cost can be reduced.

In the above embodiment, the detector 8 includes the main body 80, the friction plate 17, the steel ball 19, the detection plate 18, and the strain gauge 16, but other detection means may be used.

〔Effect of the invention〕

As described above, according to the earth and sand pumping device of the present invention, the injection amount of the viscosity imparting agent 5 can be accurately adjusted to obtain earth and sand with desired properties, and as a result, the earth and sand can be pumped efficiently. Moreover, post-processing work is unnecessary or reduced. Furthermore, it is not limited to the place of use. Moreover, costs can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a conventional earth and sand pumping device.
2 to 5 show an embodiment of the earth and sand pumping device of the present invention, FIG. 2 is a schematic diagram, FIG. 3 is an enlarged cross-sectional view of the part shown in FIG. 2, and FIG. 4 is a longitudinal cross-section of the detector. The top view and FIG. 5 are cross-sectional views taken along the - line in FIG. 4. 1... Sediment pressure pump, 2... Sediment storage tank,
3...Earth and sand pumping pipe, 5...Viscosifying agent, 6...
... Sediment, 8 ... Friction force detector, 9 ... Injection pipe, 11 ... Injection device, 16 ... Strain gauge, 17
...Friction plate, 18...Detection plate, 19...Steel ball, 2
0...Deflection rod.

Claims (1)

[Claims] 1 comprising a sediment storage tank, a sediment pump disposed in the sediment storage tank, a sediment pumping pipe connected to the sediment storage tank, and a means for supplying a viscosity imparting agent communicated with the sediment storage tank, In the earth and sand pumping device that pumps and discharges the earth and sand in the earth and sand tank through the earth and sand pump to a target location through the earth and sand pump, the earth and sand are connected to the earth and sand pump in the vicinity of the earth and sand storage tank. 1. An earth and sand pumping device, characterized in that it is equipped with a means for detecting a frictional force between the inner wall of the earth and the earth, and is configured to notify a driver of the frictional force detected by the detecting means.