SU1745831A1 - Method of working earth by dredge - Google Patents

Abstract

Use: development of soil in the underwater slaughter. During excavation, a suction curved screen with suction holes in the wellhead is buried vertically in the ground. The latter is deflected from the vertical, not detached from the ground, and rolled along a trajectory in the form of a circle around its axis. 4 il.

Description

The invention relates to the construction and is intended for the development of soil in the underwater bottom by means of hydromechanization.

Two methods of excavation have found wide application in building hydromechanization: papilonazhny and funnels.

A papilionage method of excavating a dredger is known, in which the suction tip is dug into the soil mass and soil development is papillating successively from left to right and from right to left. There is a free absorption of soil with a constant creep from the slope to the suction tip. The method provides high productivity in the grouser due to soil loosening by its constant collapse.

The disadvantage of the method lies in the fact that the erosion of the soil is easy and the slope of its slopes is easily characterized by soils not compacted, not compacted. It is not effective in compacted and compacted soils.

There is also a known method of excavating a dredger with a crater, in which the development of the soil is carried out by papillonation from top to bottom from the surface of the submerged bottom of the soil to the design depth of its development. In this case, the collapse of the soil occurs from all sides of the funnel, because the method of funnels is the most high-performance.

Especially high productivity and low energy costs for the development of soil when using suction lugs with well-developed mouths. With the developed dimensions of the tip of the funnel, large sections are obtained, the collapse and inflow of soil from the forming funnels occur more evenly and in large quantities per unit of time.

The disadvantage of the method lies in the fact that its effectiveness is drastically reduced when developing a dense and packed soil, since a single erosive effect on this soil is not enough.

J

2

cl

00

with

The purpose of the invention is to increase the efficiency of the development of dense and compacted soil in the subsea bottomhole by increasing the intensity of its erosion and suction, as well as the elimination of soil contamination with soil suspensions.

The goal is achieved by the fact that the development of the soil is carried out by free suction with a suction tip equipped with a curvilinear screen at the mouth with suction holes in the screen no larger than the flow cross section of the soil pump. During the development, the soil is subjected simultaneously and jointly by the compressive-unclenching load,

alternating hydrostatic pressure, suffusion and erosive scouring effects. For this, the suction tip is pressed into the ground by a curvilinear screen and at the same time the tip axis is deflected from the vertical. The direction of the deflection side is continually changed along a circular path. The tip is pressed into the ground by transferring to the tip of a part of the weight of the frame and the suction pipe of the dredge.

Figure 1 shows the suction tip at the surface of the ground, with the vertical position of its axis, side view; figure 2 - the same tip with the axis tilted to the left at an angle a, side view; on fig.Z - the same tip with an axis deflected at an angle and to the right, side view; Fig. 4 shows the same tip with the vertical position of the axis located at the bottom of the funnel in the ground, side view.

FIG. 1-4, the following notation is accepted: suction pipe 1; suction tip 2; curved screen 3 at the mouth of the suction tip 2; suction holes 4 in the screen 3; 5 soil bottom; zone 6 erosion in the ground; and the angle of deviation of the axis of the tip 3 from the vertical. .

The curvilinear screen 3 is made along the outline of the suction activity zone, and the suction ports 4 therein are located at a distance from each other not exceeding the sum of the radii of their active suction zones.

The method is carried out as follows.

The suction pipe of 1 dredger is lowered into the water area of the intake. Water fills the cavities of the suction tip 2 and the suction pipe 1. The ground pump is put into operation. The suction tip 2 is brought to the ground 5, and placed on the ground

priming. Soil 5 is dense because it is weakly eroded. If the tip 2 is held for a long time in the position (Fig. 1) when its axis 00 is plumb, then an erosion zone 6 of a very small size will be formed by the suction water flowing to the suction inlets 4.

To increase the intensity of the development of the soil, a part of the weight of the suction pipe 1 and the frame of the soil-collecting device of the dredge are transferred to the tip 2. To do this, it is sufficient for the bagmeister to reduce the force in the fixture holding the frame to the canopy, i.e. loosen the cable

5 ram lifting winch or reduce pressure in the hydraulic cylinder, if the frame is not equipped with a winch, hydraulic system.

As the load on the ground transmitted by the curvilinear screen increases, the bonds between the soil particles are broken, and cracks are formed in it. Through these cracks, the filtration flow of water begins (in Fig. 1 it is indicated by arrows in the axial bore 4, directed from

5 soils 5). Accordingly, erosion and entrainment of the soil particles 2 and on the axis of the tip begins in the tip.

Tip 2 is angled a. to the vertical, do not remove it from the load

0 frame and suction pipe. Turn the tip clockwise (or counterclockwise) hand, leaving the axis all the time tilted to the vertical at the same angle. In doing so, the axis of the tip moves,

5 describes the surface of the cone with the apex that went to the dirt massif 5, and each point of the axis describes a circle. The curved screen 3 of the handpiece rolls over the ground, creating a compression pressure in it and removing them. In this way, a compressive-expansion load is created in the ground. At variable load, the bond between the soil particles is disrupted. By changing the position of the screen 3

5, on the ground, in addition to mechanically disrupting the integrity of the soil massif, a powerful all-time arising and disappearing hydrostatic pressure is created, since the soil is then screened off from the water, then

0 opens to water. In addition, from the load

an increase in pressure occurs on the ground

water in soil pores. Since the zone

pressure is bordered by unloaded area

soil pore pressure destroys the bond

5 between soil particles. Suffering flow occurs along the cracks.

When the screen 3 rolls over the ground in the suction zone, there is a simultaneous and cumulative impact on the bottom soil consisting of compressive-decompressive load, alternating hydrostatic pressure, suffusion and erosion erosion effects. Under such a multi-factorial impact, the soil is intensively subjected to destruction and water intake by the canal, delivered to the cavity of the handpiece 2, and from there to the hydrotransport system of the soil pump. The stages of excavation are depicted in FIG. 1-4. As the screen 3 rolls along the ground with a deviation of the axis 00 from the plumb position (FIG. 1), the angle is “(FIG. 2), to the right (FIG. 3), to the left and return to the plumb position (FIG. 4) soil increases in size both in depth and in diameter.

After the development of the funnel to the design depth, the suction tip is raised to the level of the soil surface, shifted by the diameter of the formed crow

ki and produce the second funnel, next to it - the third, fourth, etc.

Claims (1)

The invention The method of developing a soil dredger, which includes the development of soil by embedding a vertical suction curvilinear screen with suction holes in the mouth, not exceeding the size of the ground pump, in order to increase the efficiency of developing dense and packed soil by increasing the intensity of its erosion and suction, the suction curved screen is deflected from the vertical, while not tearing the screen off the ground, roll the screen along a path rii in the form of a circle around its axis. ABOUT