Widened drag head of drag suction dredger

Abstract

The invention discloses a widened drag head of a drag suction dredger. The widened drag head comprises a fixed body, a movable cover, a double-row rake tooth assembly, a high-pressure flushing assembly and a movable driving assembly. The movable cover is movably connected to the front side of the fixed body, and a double-row rake tooth assembly is arranged in the movable cover; the high-pressure flushing assembly is arranged at the upper end of the fixing body and communicates with the double-row rake tooth assembly. The movable driving assembly is arranged at the upper end of the fixed body and connected with the movable cover. According to the widened drag head of the drag suction dredger, the defects in the prior art are overcome, and the construction efficiency during operation is improved.

Description

Technical Field

[0001] The present invention relates to a widened drag head of a trailing suction hopper dredger. Background Art

[0002] The drag head is one of the main dredging equipments of a trailing suction hopper dredger, and is installed at the lower end of the drag suction pipe. During dredging operations, the drag head is close to the bottom mud surface, loosens the soil and dredges the mud under the towing of the ship, and then the mud pump sucks the mud and water together and discharges them into the mud hold, or realizes side casting to achieve the purpose of dredging.

[0003] Due to the unreasonable design of the head of the existing drag head of the trailing suction hopper dredger, the drag head is prone to damage during operation, has a short service life, and has low construction efficiency. Therefore, a widened drag head of a trailing suction hopper dredger is proposed to solve the above problems. Summary of the Invention

[0004] The purpose of the present invention is to provide a widened drag head of a trailing suction hopper dredger to overcome the existing defects and improve the construction efficiency during operation.

[0005] To achieve the above purpose, the present invention provides the following technical solutions: A widened drag head of a trailing suction hopper dredger, comprising a fixed body, a movable cover, a double-row drag tooth assembly, a high-pressure flushing water assembly and a movable driving assembly;

[0006] The movable cover is movably connected to the front side of the fixed body, and a double-row drag tooth assembly is arranged inside the movable cover; the high-pressure flushing water assembly is arranged at the upper end of the fixed body and communicates with the double-row drag tooth assembly; the movable driving assembly is arranged at the upper end of the fixed body and is connected to the movable cover.

[0007] Preferably, the double-row drag tooth assembly includes a front-row high-pressure flushing water tank, a rear-row high-pressure flushing water tank, a front-row tooth seat group and a rear-row tooth seat group; the front-row high-pressure flushing water tank and the rear-row high-pressure flushing water tank are respectively arranged inside the inner side of the movable cover, the bottom plate of the front-row high-pressure flushing water tank is connected to the front-row tooth seat group, the bottom plate of the rear-row high-pressure flushing water tank is connected to the rear-row tooth seat group, a plurality of first drag teeth are connected to the front-row tooth seat group, and a plurality of second drag teeth are connected to the rear-row tooth seat group.

[0008] Preferably, the high-pressure flushing water assembly includes a main high-pressure flushing water pipe, two first branch high-pressure flushing water pipes and two second branch high-pressure flushing water pipes. The lower end of the main high-pressure flushing water pipe penetrates to the lower end of the fixed body, the upper end of the main high-pressure flushing water pipe is respectively connected to the two first branch high-pressure flushing water pipes and the two second branch high-pressure flushing water pipes, and the other ends of the two first branch high-pressure flushing water pipes and the two second branch high-pressure flushing water pipes respectively communicate with the front-row high-pressure flushing water tank and the rear-row high-pressure flushing water tank.

[0009] Preferably, the movable driving assembly includes two oil cylinder supports, two oil cylinders and two connecting seats; the two oil cylinder supports are respectively connected to both sides of the fixed body, the two connecting seats are respectively connected to both sides of the movable cover, the fixed ends of the two oil cylinders are respectively rotatably connected to the two oil cylinder supports, and the extending ends of the two oil cylinders are respectively rotatably connected to the two connecting seats.

[0010] Preferably, wear-resistant blocks are provided at the lower end of the fixed body.

[0011] Preferably, wear-resistant baffles are provided on both sides of the lower end of the movable cover.

[0012] Preferably, a grille is provided inside the movable cover.

[0013] Preferably, a water diversion window is provided on the side wall of the movable cover.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: the widened rake head of this trailing suction hopper dredger is provided with a double-row rake tooth assembly inside the movable cover; a high-pressure flushing assembly is provided to communicate with the double-row rake tooth assembly; at the same time, on the basis of the ordinary rake head, it is widened by 800 mm, increasing the single-pass raking area, increasing the excavation volume, improving the construction efficiency during operation, and achieving the purpose of saving costs, saving time and improving the project quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings are used to provide a further understanding of the present invention, and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention, and do not constitute a limitation to the present invention. In the drawings:

[0016] Figure 1 is an axonometric view of the widened rake head of the trailing suction hopper dredger of the present invention;

[0017] Figure 2 is a top view of the widened rake head of the trailing suction hopper dredger of the present invention;

[0018] Figure 3 is a front view of the widened rake head of the trailing suction hopper dredger of the present invention;

[0019] Figure 4 is a side view of the widened rake head of the trailing suction hopper dredger of the present invention;

[0020] Figure 5 is the first motion state of the widened rake head of the trailing suction hopper dredger of the present invention;

[0021] Figure 6 is the second motion state of the widened rake head of the trailing suction hopper dredger of the present invention.

[0022] In the figure: 1. Fixed body; 2. Movable cover; 3. Front row high-pressure flushing water tank; 4. Rear row high-pressure flushing water tank; 5. Front row tooth seat group; 6. Rear row tooth seat group; 7. First rake tooth; 8. Second rake tooth; 9. Main high-pressure flushing water pipe; 10. First branch high-pressure flushing water pipe; 11. Second branch high-pressure flushing water pipe; 12. Oil cylinder support; 13. Oil cylinder; 14. Connecting seat; 15. Wear-resistant block; 16. Anti-wear baffle; 17. Grille; 18. Water intake window. Specific embodiments

[0023] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0024] In view of the characteristics of typical silting sediment in the deep water channel of the Yangtze Estuary, the hopper capacity of the trailing suction hopper dredger, the sediment precipitation characteristics, and the excavation efficiency of the dredging head, the present invention adopts a technical solution of hydraulic flushing + wide dredging head closed suction. According to the diameter of the dredging pipe and the maximum load of the lifting system, the optimal widening scale and the ratio of the suction area are designed, and the high-pressure flushing layout, cavity structure and line type of the dredging head are optimized to reduce the suction resistance, increase the passing area and suction ratio of the dredging head, and improve the dredging efficiency of the trailing suction hopper dredger.

[0025] Please refer to Figure 1-6 , a widened dredging head of a trailing suction hopper dredger, including a fixed body 1, a movable cover 2, a double-row rake tooth assembly, a high-pressure flushing assembly and a movable drive assembly; the movable cover 2 is movably connected to the front side of the fixed body 1, and a double-row rake tooth assembly is arranged inside the movable cover 2; the high-pressure flushing assembly is arranged at the upper end of the fixed body 1 and communicates with the double-row rake tooth assembly; the movable drive assembly is arranged at the upper end of the fixed body 1 and is connected to the movable cover 2.

[0026] Specifically, the widened dredging head is mainly used for construction in the Yangtze Estuary area. The width of its movable cover is greater than that of a conventional dredging head by 3996 mm, and the effective design width reaches 4796 mm. It is widened by 800 mm on the basis of a common dredging head, increasing the single-pass area and the excavation volume, improving the construction efficiency during operation, so as to achieve the purpose of saving costs, saving time and improving the project quality.

[0027] Specifically, a sealing device is arranged between the fixed body 1 and the movable cover 2. The sealing device is composed of a sealing rubber strip, a seat plate and a pressing plate. The rubber sealing strip is locked by bolts and the pressing plate to prevent extra water from entering between the fixed body and the movable cover during dredging, reducing vacuum loss.

[0028] Specifically, the movable cover 2 is made of steel by welding. The movable cover 2 is formed into a portal shape by electric welding of steel plates, with a shaft hole at the rear, and is hinged to the fixed body 1 with a short shaft, and can rotate up to 50°. The internal frame structure is used as the cross beam to strengthen the structure of the movable cover. The movable cover 2 undertakes the work of the excavator head for excavation, hydraulic flushing, mud mixing and transportation. The internal flow pattern and pressure change are complex, and the wear of the soil particles on the structure is also very serious.

[0029] Specifically, during the excavation of the excavator head, the angle to the ground is adjusted according to different cutting depths to prevent sediment from escaping to both sides. The function of the water inlet window is to adjust the vacuum degree inside the excavator head when the concentration of the excavated soil in the excavator head is relatively high, and part of the clear water is sent in through the water inlet window to prevent the problem of the excavator head being blocked. The function of the grille is to block the larger stones dug up by the excavator head and cause irreversible wear to the excavator head and the mud conveying pipeline. During excavation, the wear-resistant blocks are deeply embedded in the soil layer. After the soil body is damaged by high-pressure flushing water, the mud mixture is dispersed in all corners of the excavator head cavity. The wear-resistant blocks block these mixtures from the outside and suck them all into the pipeline.

[0030] Specifically, the double-row rake tooth assembly includes a front row high-pressure flushing water tank 3, a rear row high-pressure flushing water tank 4, a front row tooth seat group 5 and a rear row tooth seat group 6; the front row high-pressure flushing water tank 3 and the rear row high-pressure flushing water tank 4 are respectively arranged on the inner side of the movable cover 2. The front row tooth seat group 5 is connected to the bottom plate of the front row high-pressure flushing water tank 3, and the rear row tooth seat group 6 is connected to the bottom plate of the rear row high-pressure flushing water tank 4. A plurality of first rake teeth 7 are connected to the front row tooth seat group 5, and a plurality of second rake teeth 8 are connected to the rear row tooth seat group 6.

[0031] Specifically, the front and rear rows of rake teeth are arranged staggeredly. The type of the rake teeth of the excavator head is T2 wide teeth, and the type of the tooth seat is T2 standard tooth seat. The commonly used rake teeth also include T2 narrow teeth, T2 single plow teeth and T2 double plow teeth.

[0032] Specifically, the tooth seat and the rake teeth are fastened by spring latches, which is convenient for the replacement of the rake teeth to achieve the purpose of quick replacement and maintenance. The tip heights of the two rows of rake teeth are flush.

[0033] Specifically, the high-pressure flushing water component includes a main high-pressure flushing water pipe 9, two first branch high-pressure flushing water pipes 10 and two second branch high-pressure flushing water pipes 11. The lower end of the main high-pressure flushing water pipe 9 penetrates to the lower end of the fixed body 1. The upper end of the main high-pressure flushing water pipe 9 is respectively connected to the two first branch high-pressure flushing water pipes 10 and the two second branch high-pressure flushing water pipes 11. The other ends of the two first branch high-pressure flushing water pipes 10 and the two second branch high-pressure flushing water pipes 11 are respectively communicated with the front row high-pressure flushing water tank 3 and the rear row high-pressure flushing water tank 4.

[0034] The head of the high-pressure flushing pump is 10 bar and the flow rate is 3,000 m³ / h. When the water shoots out from the nozzle, the dynamic water head is equal to the pump head minus the total resistance loss head of the high-pressure water transmission. The diameter of the high-pressure flushing pipe is 400 mm. By numerically simulating the high-pressure flushing process, the head loss due to pipe resistance along the way is about 17.5 m.

[0035] There are two layout methods for the nozzles on the sandy soil type drag head. Layout 1: Use the middle row of nozzles and cooperate with wear-resistant block nozzles with a smaller diameter, a total of 5 rows of nozzles. Layout 2: Block one row of nozzles and cooperate with wear-resistant block nozzles with a larger diameter, a total of 4 rows of nozzles. Either of the two layouts can be selected, or they can be switched according to different soil conditions. In Layout 1, an additional row of water tank nozzles is added between the teeth in the middle row, using water to fill the pores after the soil is damaged, reducing the negative pressure in the compacted soil gaps, thereby improving the soil-breaking ability. At the same time, it has the functions of crushing soil and replenishing water.

[0036] High-pressure flushing nozzle configuration for ordinary sandy soil drag head

[0037] The high-pressure water tank bottom plate of the fixed body is provided with 25 wear-resistant blocks. The type of rake teeth in the movable cover is wide teeth, 20 in the front row and 20 in the back row. The narrow teeth DRC-DJ-ES01-Z can be used interchangeably. Adopt Layout 1, with a total of 5 high-pressure flushing circuits.

[0038]

[0039]

[0040] High-pressure flushing nozzle layout for widened sandy soil drag head

[0041] The high-pressure water tank bottom plate is provided with 29 wear-resistant blocks. The type of rake teeth in the movable cover is wide teeth, 24 in the front row and 24 in the back row. The narrow teeth DRC-DJ-ES01-Z can be used interchangeably. Adopt Layout 2, with a total of 4 high-pressure flushing circuits.

[0042]

[0043] The optimized flow channel of the nozzle reduces the resistance loss. The ceramic inner core is adopted to improve the wear resistance. The nozzle is installed on the welded thread to improve the convenience of replacement, and at the same time, the height of the nozzle outlet from the mud surface is reduced. In view of the common wear, falling off and damage of the wear-resistant blocks, the shape of the vulnerable surface of the wear-resistant block is optimized to reduce the probability of accidental damage and the frictional resistance. In the past, the shape of the wear-resistant block was in the form of a cube chamfer, and it was fixed by welding and hexagon socket head cap screws. After improvement, the vulnerable surface of the wear-resistant block has an arc transition and is installed by welding.

[0044] Specifically, the main high-pressure flushing pipe 9 is connected to the drag pipe high-pressure flushing pipe through the main high-pressure flushing pipe flange. The lower end of the main high-pressure flushing pipe 9 is connected to the ceramic nozzle. The high-pressure water sprays out through the nozzle, and the soil is broken, liquefied and suspended under the action of the high-pressure water to form mud.

[0045] Specifically, the movable driving assembly includes two oil cylinder supports 12, two oil cylinders 13 and two connecting seats 14; the two oil cylinder supports 12 are respectively connected to both sides of the fixed body 1, the two connecting seats 14 are respectively connected to both sides of the movable cover 2, the fixed ends of the two oil cylinders 13 are respectively rotatably connected to the two oil cylinder supports 12, and the extending ends of the two oil cylinders 13 are respectively rotatably connected to the two connecting seats 14.

[0046] Specifically, the oil cylinder 13 is supplied with oil by the ship's hydraulic station to the drag head hydraulic cylinder, adjusting the angle between the movable cover 2 of the drag head and the mud surface, so that the movable cover 2 closely adheres to the mud surface to prevent excessive intake of clear water and reduce the mud concentration. At the same time, the drag teeth break the soil with a reasonable cutting angle and cutting resistance, so as to achieve the purpose of increasing the mud concentration and improving the dredging efficiency.

[0047] Specifically, wear-resistant blocks 15 are provided at the lower end of the fixed body 1. It is made of composite materials, can be welded at the bottom, and is wear-resistant on the surface, preventing excessive wear when the fixed body contacts the seabed, and is convenient for replacement at the same time.

[0048] Specifically, an anti-collision device is provided on one side of the fixed body 1 to prevent the drag head from being damaged by collision with the hull.

[0049] Specifically, anti-wear crescent baffles are installed on both sides of the fixed body 1 to prevent seawater from entering the drag head from both sides of the drag head.

[0050] Specifically, anti-wear baffles 16 are provided on both sides of the lower end of the movable cover 2. During dredging, the anti-wear baffles press on the soil, preventing excessive wear of the movable cover, and at the same time preventing the sediment suspended by the high-pressure flushing water from escaping to both sides.

[0051] Specifically, a grille 17 is provided inside the movable cover 2. The grille 17 is installed inside the movable cover 2 to prevent large soil blocks or rocks from entering the pipeline and the impeller and causing blockage, and the grille is convenient for replacement. The width of the grille channel is slightly smaller than the passing ball diameter of the mud pump impeller.

[0052] Specifically, water inlet windows 18 are provided on the side wall of the movable cover 2. During the operation of the drag head, a pressure difference is generated inside and outside the movable cover 2. The size of the pressure difference is related to the construction soil quality, and a water hammer phenomenon may occur due to too large a pressure difference. To avoid this phenomenon, four water inlet windows are provided on the upper part of the movable cover of the drag head, and the water inflow of the water inlet windows is adjusted according to different construction conditions. When excavating soil such as silt, to prevent the drag head from being blocked, the water inlet windows can be opened to enable normal dredging operations.

[0053] The widened drag head of this trailing suction hopper dredger has a double-row drag tooth assembly arranged inside the movable cover 2; a high-pressure flushing water assembly is provided to connect the double-row drag tooth assembly; at the same time, it is widened by 800 mm on the basis of the ordinary drag head, increasing the single-pass raking area, increasing the excavation volume, improving the construction efficiency during operation, and achieving the purpose of saving costs, saving time and improving the project quality.

[0054] Reduce the large angle bends in the flow channels, use arc-shaped plates for the movable hood fixing body, and achieve a smooth transition for the internal flow channels. The bottom of the fixing body at the high-pressure water tank point adopts a circular arc transition and is strengthened to reduce the wear of the wear-resistant blocks. After the optimization and improvement, the internal flow field distribution of the drag head is relatively uniform, and there is basically no obvious eddy current area or low flow velocity area. Therefore, the flow resistance of the slurry in the drag head can be reduced, thereby reducing energy consumption. Under the same working conditions, the device cavitation margin of the conveying system is increased, and the dredging efficiency of the drag head is improved.

[0055] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A widened drag head of a trailing suction dredger, characterized in that: It comprises a fixed body (1), a movable cover (2), a double-row rake tooth assembly, a high-pressure flushing assembly and a movable driving assembly; The movable cover (2) is movably connected to the front side of the fixed body (1), and a double-row rake tooth assembly is arranged in the movable cover (2); the high-pressure flushing assembly is arranged at the upper end of the fixed body (1) and is connected to the double-row rake tooth assembly; the movable driving assembly is arranged at the upper end of the fixed body (1) and is connected to the movable cover (2).

2. The widened drag head of a trailing suction hopper dredger according to claim 1, characterized in that: The double-row rake tooth assembly comprises a front-row high-pressure flushing water tank (3), a rear-row high-pressure flushing water tank (4), a front-row tooth seat group (5) and a rear-row tooth seat group (6); the front-row high-pressure flushing water tank (3) and the rear-row high-pressure flushing water tank (4) are respectively arranged on the inner side of the movable cover (2); the front-row tooth seat group (5) is connected to the bottom plate of the front-row high-pressure flushing water tank (3); the rear-row tooth seat group (6) is connected to the bottom plate of the rear-row high-pressure flushing water tank (4); a plurality of first rake teeth (7) are connected to the front-row tooth seat group (5); and a plurality of second rake teeth (8) are connected to the rear-row tooth seat group (6).

3. The widened drag head of a trailing suction dredger according to claim 2, characterized in that: The high-pressure flushing assembly comprises a main high-pressure flushing pipe (9), two first branch high-pressure flushing pipes (10) and two second branch high-pressure flushing pipes (11); the lower end of the main high-pressure flushing pipe (9) penetrates the lower end of the fixed body (1); the upper end of the main high-pressure flushing pipe (9) is respectively connected to the two first branch high-pressure flushing pipes (10) and the two second branch high-pressure flushing pipes (11); the other ends of the two first branch high-pressure flushing pipes (10) and the two second branch high-pressure flushing pipes (11) are respectively connected to the front-row high-pressure flushing water tank (3) and the rear-row high-pressure flushing water tank (4).

4. The widened drag head of a trailing suction hopper dredger according to claim 2, characterized in that: The movable driving assembly comprises two cylinder supports (12), two cylinders (13) and two connecting seats (14); the two cylinder supports (12) are respectively connected to the two sides of the fixed body (1), the two connecting seats (14) are respectively connected to the two sides of the movable cover (2), the fixed ends of the two cylinders (13) are respectively rotatably connected to the two cylinder supports (12), and the extended ends of the two cylinders (13) are respectively rotatably connected to the two connecting seats (14).

5. The widened drag head of a trailing suction hopper dredger according to claim 2, characterized in that: A wear-resistant block (15) is provided at the lower end of the fixed body (1).

6. The widened drag head of a trailing suction hopper dredger according to claim 2, characterized in that: Anti-wear baffles (16) are provided on both sides of the lower end of the movable cover (2).

7. The widened drag head of a trailing suction hopper dredger according to claim 2, characterized in that: A grille (17) is provided on the inner side of the movable cover (2).

8. The widened drag head of a trailing suction hopper dredger according to claim 2, characterized in that: A water guide window (18) is provided on the side wall of the movable cover (2).

Images