Fixed-point spraying and flushing device for operation cabin and spraying and flushing method of fixed-point spraying and flushing device

Abstract

The invention discloses an operation cabin fixed-point spraying and flushing device and a spraying and flushing method thereof, and relates to the technical field of wellhead desilting equipment. The spraying frame is connected with the inner wall of the operation cabin, a plurality of combined nozzles are arranged on the spraying frame, and the plurality of combined nozzles are respectively connected with a spraying pipeline; and the multiple dredging pumps are arranged on the spraying and flushing frame. According to the working cabin fixed-point spraying device and the spraying method thereof, the technical problems that an existing under-mud wellhead dredging device is high in operation cost, manual local dredging is needed after construction of a mud blowing ship is completed, and the risks of silt back silting, pit collapse and the like exist are solved, spraying liquid is input into the combined nozzle through the spraying pipeline and sprayed out at a high speed through the combined nozzle, and the working efficiency is improved. Sludge at the position of an operation seabed area is directly sprayed, flushed and scattered, meanwhile, silt is sucked through the dredging pump and discharged out of the operation seabed area through the sludge discharging pipeline, manual local dredging is not needed any more, the operation cost is effectively reduced, and the sludge spraying efficiency is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wellhead dredging equipment, and particularly relates to a work cabin fixed-point jetting device and a jetting method thereof. BACKGROUND

[0002] A submarine pipeline is an important facility for oil and gas transportation in the development of offshore oil and gas fields. The conventional mudline suspension completes the abandonment of the well, and the corrosion cap of the riser is generally above the mud surface. In order to reduce the influence of construction operation on the waterway, fishery production and military safety, the well needs to be abandoned at a position 4m below the mud surface, and the wellhead needs to be dredged to provide enough operation space for the wellhead connection of the mudline hanger. It is difficult to excavate a certain volume of operation space at a position 4m below the mud surface. At present, common operation methods include underwater mechanical direct excavation, hydraulic jetting air lifting and hydraulic jetting mud discharge, among which hydraulic jetting is the main method.

[0003] At present, the well below the mud is usually dredged by manual or mud blowing ship. The larger the range of exposed well that needs to be broken, the more expensive the supporting professional mud blowing ship and other ship machinery, and the higher the operation cost. On the other hand, after the mud blowing ship completes the construction, local dredging needs to be carried out manually. Since there is no protective measure around the soil body, there are risks of siltation, pit collapse and other problems, causing personal injury and other problems. Therefore, a work cabin fixed-point jetting device and a jetting method thereof are proposed to solve the above problems. SUMMARY

[0004] The purpose of the present application is to provide a work cabin fixed-point jetting device and a jetting method thereof, which solves the technical problems of high operation cost of the existing well below the mud dredging equipment, local dredging needs to be carried out manually after the mud blowing ship completes the construction, and there are risks of siltation, pit collapse and other problems, causing personal injury.

[0005] To achieve the above purpose, the present application provides a work cabin fixed-point jetting device, which comprises:

[0006] a work cabin;

[0007] a jetting frame connected to the inner wall of the work cabin through adjusting bolts, a plurality of combined nozzles are arranged on the jetting frame, a plurality of combined nozzles are connected to jetting pipelines respectively, and the jetting pipelines are used for inputting jetting liquid to the combined nozzles;

[0008] a plurality of dredging pumps arranged on the jetting frame, a plurality of dredging pumps are connected to mud discharge pipelines respectively, and the mud discharge pipelines are used for discharging the silt sucked by the dredging pumps.

[0009] Preferably, the combined nozzle comprises a nozzle passage, a first end of the nozzle passage is threadedly connected to the jetting pipeline, and a plurality of nozzles are arrayed at a second end of the nozzle passage.

[0010] Preferably, the included angle between the axis of the nozzle and the axis of the nozzle passage is between 10-30°, and the axis of one of the nozzles coincides with one of the radius sections of the jet frame.

[0011] Preferably, the jet frame comprises a lower ring, the top of the lower ring is connected to a plurality of vertical supports, and the upper ends of the vertical supports are connected to an upper ring.

[0012] Preferably, an inner ring is coaxially arranged on the inner side of the lower ring, the lower ring is connected to the inner ring through a connecting rod, and the dredging pump and the combined nozzle are alternately arranged on the inner ring.

[0013] Preferably, the inner ring is arranged directly above the wellhead, and the diameter of the inner ring is greater than the maximum projection size of the wellhead and leaves a working space.

[0014] Preferably, the working cabin is coaxially arranged with the jet frame, and the distance between the inner side wall of the working cabin and the outer side wall of the jet frame is between 5-20mm.

[0015] Preferably, a suction nozzle is arranged on the dredging pump, a fixed plate is arranged at the first end of the suction nozzle, the fixed plate is connected to the jet frame, and the second end of the suction nozzle is in the shape of a cone.

[0016] Correspondingly, the technical scheme of the application also provides a working cabin fixed-point jetting method of the working cabin fixed-point jetting device, comprising:

[0017] S1: installing the jet frame in the working cabin and adjusting the distance between the combined nozzle and the bottom surface of the working cabin; alternately arranging the dredging pump and the combined nozzle on the jet frame, connecting the combined nozzle to the jetting pipeline and connecting the dredging pump to the mud discharge pipeline, and connecting the jetting pipeline and the mud discharge pipeline to the working mother ship;

[0018] S2: the working mother ship lowers the working cabin to the working seabed area through the hoisting device, the jetting liquid is input into the combined nozzle through the jetting pipeline and is jetted out at high speed through the combined nozzle, and the dredging pump is started to suck in the silt and discharge the silt out of the working seabed area through the mud discharge pipeline;

[0019] S3: the working mother ship is slowly lowered by the hoisting device until the entire working seabed area is jetted, the wellhead is connected, and the working cabin is lifted by the hoisting device until it leaves the working seabed area.

[0020] Preferably, the distance between the combined nozzle and the bottom surface of the working cabin is determined by simulation analysis and calculation according to the jetting pressure and jetting speed.

[0021] With respect to the above background art, the present application provides a work cabin fixed-point jetting device, which has the following beneficial effects: after the work cabin and the jetting frame are placed on the work seabed area, the jetting liquid is input into the combined nozzle through the jetting pipeline and is sprayed out at high speed through the combined nozzle, the silt at the position of the work seabed area is directly jetted and scattered, the traditional soil breaking method of the mud blowing ship is replaced, the operation cost is effectively reduced, and the silt jetting efficiency is improved. On the other hand, the silt is sucked by the dredging pump and is discharged from the work seabed area through the mud discharge pipeline, manual local dredging is no longer needed, the soil at the wellhead position is assisted and supported by the jetting frame, the risks such as silt backfilling and pit collapse are prevented, and the safety during operation is effectively improved. The work cabin fixed-point jetting method used in the present application also has the above beneficial effects. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description only constitute the embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of the provided drawings.

[0023] Figure 1 An assembly schematic view of the jetting device provided by the embodiments of the present application;

[0024] Figure 2 A bottom view of the jetting device provided by the embodiments of the present application;

[0025] Figure 3 A cross-sectional schematic view of the work cabin provided by the embodiments of the present application;

[0026] Figure 4 A three-dimensional structural view of the jetting frame provided by the embodiments of the present application;

[0027] Figure 5 A plan view of the jetting device provided by the embodiments of the present application;

[0028] Figure 6 A three-dimensional structural view of the combined nozzle provided by the embodiments of the present application;

[0029] Figure 7 A cross-sectional schematic view of the combined nozzle provided by the embodiments of the present application;

[0030] Figure 8 A three-dimensional structural view of the suction nozzle provided by the embodiments of the present application.

[0031] Specifically, 1 - work cabin; 2 - jet frame; 201 - upper ring; 202 - lower ring; 203 - inner ring; 204 - vertical support; 205 - connecting rod; 206 - inclined strut; 3 - adjusting bolt; 4 - combined nozzle; 401 - connecting thread; 402 - nozzle passage; 403 - nozzle; 404 - nozzle mounting seat; 405 - stepped groove; 5 - dredging pump; 6 - tray; 7 - jet pipeline; 8 - sludge discharge pipeline; 9 - suction nozzle. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0033] In order for those skilled in the art to better understand the present application, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0034] As shown in Figure 1 and Figure 3 To achieve the above-mentioned purpose, the present application provides a work cabin 1 fixed-point jetting device, comprising: a work cabin 1 and a jet frame 2 arranged in the work cabin 1.

[0035] Among them, the work cabin 1 is barrel-shaped as a whole, preferably, the work cabin 1 is assembled into shape by welding, mainly providing mounting space for the jet frame 2, the jet frame 2 is arranged on the top surface of the work cabin 1, and the jet frame 2 is connected to the inner wall of the work cabin 1 through the adjusting bolt 3. It should be noted that the jet frame 2 is cylindrical as a whole, when the work cabin 1 is placed in the work seabed area, the jet frame 2 is located directly above the wellhead, and the jet frame 2 is used to assist the support of the soil at the wellhead position, preventing the risk of silt backfilling and pit collapse, effectively improving the safety during work.

[0036] As shown in Figure 2 The jet frame 2 is provided with a plurality of combined nozzles 4, and the plurality of combined nozzles 4 are connected to the jet pipeline 7 respectively, and the jet pipeline 7 is used to input jetting liquid to the combined nozzle 4, wherein the jetting liquid can be sea water, which is taken and used, and the jetting liquid is sprayed out at high speed through the combined nozzle 4 to jet the silt in the work seabed area, quickly dispersing the silt at the wellhead position, compared with the traditional blowing mud ship breaking soil method, effectively reducing the operation cost, and the silt jetting is more efficient.

[0037] A plurality of trays 6 are arranged on the jetting frame 2, and a dredging pump 5 is arranged on each tray 6. The dredging pump 5 sucks the silt after the silt is dispersed by the combined nozzle 4. The dredging pump 5 is connected to a mud discharge pipeline 8. The dredging pump 5 discharges the sucked silt through the mud discharge pipeline 8 to the seabed area. The manual local dredging is not needed, and the risk of silt backfilling is prevented, and the operation is safer.

[0038] In use, the jetting frame 2 is arranged in the operation cabin 1, and the distance between the combined nozzle 4 and the bottom surface of the operation cabin 1 is adjusted. The combined nozzle 4 and the dredging pump 5 are alternately arranged on the jetting frame 2. The combined nozzle 4 is connected to the jetting pipeline 7, and the dredging pump 5 is connected to the mud discharge pipeline 8. The jetting pipeline 7 and the mud discharge pipeline 8 are connected to the working mother ship. The working mother ship lowers the operation cabin 1 to the seabed area by the hoisting device. The jetting frame 2 assists in supporting the soil at the wellhead position to prevent the risk of pit collapse. The jetting liquid is input into the combined nozzle 4 through the jetting pipeline 7 and is jetted at high speed through the combined nozzle 4 to disperse the silt at the wellhead position. Compared with the conventional mud blowing ship, the operation cost is effectively reduced, and the silt jetting efficiency is improved. The silt is sucked by the dredging pump 5 and is discharged to the seabed area through the mud discharge pipeline 8. The whole process does not need manual local dredging and other related operations. Even if the risks of silt backfilling and pit collapse occur, the workers will not be harmed, and the workers have no related operation risks. The working mother ship is slowly lowered by the hoisting device until the whole seabed area is jetted.

[0039] As shown in Figure 6 and Figure 7 , the combined nozzle 4 comprises a nozzle passage 402. The upper end of the nozzle passage 402 is provided with a connecting thread. The nozzle passage 402 is connected to the jetting pipeline 7 through the connecting thread 401. The jetting pipeline 7 inputs the jetting liquid into the nozzle passage 402. A plurality of nozzles 403 are arranged at the lower end of the nozzle passage 402. Specifically, three nozzles 403 are arranged at the lower end of each nozzle passage 402 at equal angles. The jetting liquid is input into each nozzle 403 through the nozzle passage 402. The jetting liquid is jetted at high speed through the nozzles 403 to disperse the silt. In addition, a nozzle mounting seat 404 is arranged on the outer circumferential side of the upper end of the nozzle 403. The combined nozzle 4 is fixed to the jetting frame 2 through the nozzle mounting seat 404.

[0040] In addition, a stepped groove 405 is arranged at the upper end of the nozzle passage 402. A sealing ring is arranged at the position of the stepped groove 405. The sealing ring is arranged to tightly connect the combined nozzle 4 and the jetting pipeline 7 to avoid water leakage at the connection between the combined nozzle 4 and the jetting pipeline 7.

[0041] It should be noted that the angle between the axis of the nozzle 403 and the axis of the nozzle passage 402 is between 10-30°, that is, the nozzle 403 is not perpendicular to the bottom surface of the jetting frame 2, preferably, the angle between the axis of the nozzle 403 and the axis of the nozzle passage 402 is 22.5°, which can maximize the jetting area covered by the three nozzles 403, while ensuring the impact effect of the jetting liquid on the sludge after being sprayed from the nozzle 403.

[0042] Further, the axis of one of the nozzles 403 coincides with one of the radius sections of the jetting frame 2, specifically, one of the nozzles 403 in each combined nozzle 4 sprays the jetting liquid to the outside of the working seabed area. The coverage of the jetting liquid sprayed by the other two nozzles 403 respectively connects with the coverage of the jetting liquid sprayed by the nozzles 403 in the adjacent combined nozzle 4 as much as possible, thereby ensuring that the jetting of the nozzles 403 on the sludge of the working seabed area achieves the optimal coverage, and effectively improves the jetting efficiency of the sludge of the working seabed area by each combined nozzle 4.

[0043] As shown in Figure 4 and Figure 5 , the jetting frame 2 comprises a lower ring 202, the top of the lower ring 202 is connected to a plurality of vertical supports 204, the upper ends of the plurality of vertical supports 204 are connected to an upper ring 201, specifically, the upper ring 201 and the lower ring 202 are connected by four vertical supports 204 to assemble the jetting frame 2 into a cylindrical structure. In addition, an inner ring 203 is coaxially arranged on the inner side of the lower ring 202, and the lower ring 202 is connected to the inner ring 203 by a connecting rod 205. Specifically, the upper ring 201 and the inner ring 203 are further connected by a diagonal brace 206, and the diagonal brace 206, the vertical support 204 and the connecting rod 205 form a stable triangular structure, which can improve the stability of the whole jetting frame 2, so that the jetting frame 2 has sufficient structural strength during operation, thereby ensuring the stability of the combined nozzle 4 and the dredging pump 5 during operation.

[0044] In one embodiment of the present application, the dredging pump 5 and the combined nozzle 4 are alternately arranged on the inner ring 203, wherein the combined nozzle 4 and the dredging pump 5 are alternately and uniformly distributed, each combined nozzle 4 is adjacent to two dredging pumps 5, and the distance between each adjacent combined nozzle 4 and dredging pump 5 is equal, and the distance between the adjacent two combined nozzles 4 and the distance between the adjacent two dredging pumps 5 are equal, so as to ensure that the working seabed area can be uniformly jetted by each combined nozzle 4, and further improve the jetting efficiency of the sludge of the working seabed area by each combined nozzle 4.

[0045] In addition, the number of dredging pumps 5 and combined nozzles 4 is selected according to the size of the wellhead, so as to ensure that each combined nozzle 4 can jet the sludge of each part of the working seabed area as much as possible, and improve the jetting efficiency of the sludge of the working seabed area.

[0046] As Figure 8 shown, the suction nozzle 9 is provided on the dredge pump 5, the upper end of the suction nozzle 9 is threadedly connected with the dredge pump 5, the outer side wall of the upper end of the suction nozzle 9 is provided with a fixing plate, the fixing plate is connected with the jetting frame 2, and the fixing plate is used for assisting in fixing the suction nozzle 9. The lower end of the suction nozzle 9 is in the shape of a cone as a whole, the suction area of the suction nozzle 9 is increased, and the efficiency of the dredge pump 5 in sucking in the silt is further improved.

[0047] It should be noted that the inner ring 203 is arranged directly above the wellhead, and the diameter of the inner ring 203 is greater than the maximum projection size of the wellhead, so as to ensure that the combined nozzle 4 and the dredge pump 5 can jet and suck clean the silt directly above the wellhead and the silt near the wellhead, a certain operation space is reserved for the wellhead, and the smooth performance of the wellhead is ensured.

[0048] In an embodiment of the present application, the top surface of the upper ring 201 is arrayed with a plurality of first lifting rings, the first lifting rings are used for connecting a lifting device, the lifting device is arranged on a working mother ship, the first lifting rings are connected with the lifting device on the working mother ship, the whole jetting frame 2 is lifted into the operation cabin 1 through the lifting device. In addition, the outer circumferential side surface of the upper end of the operation cabin 1 is arrayed with a plurality of second lifting rings, the second lifting rings are used for connecting the lifting device, when the jetting frame 2 is lifted into the operation cabin 1 and stably installed, the operation cabin 1 is lifted together with the jetting frame 2 to the operation seabed area through the lifting device connecting the second lifting rings, and the fixed-point delivery of the operation cabin 1 is completed.

[0049] It should be noted that the operation cabin 1 and the jetting frame 2 are coaxially arranged, and the distance between the inner side wall of the operation cabin 1 and the outer side wall of the jetting frame 2 is between 5-20 mm, that is, a certain assembly space is reserved between the operation cabin 1 and the jetting frame 2, so as to avoid that the jetting frame 2 is stuck in the operation cabin 1, and the later disassembly and maintenance and replacement are not affected. Preferably, the distance between the inner side wall of the operation cabin 1 and the outer side wall of the jetting frame 2 is 10 mm. Specifically, when the adjusting bolt 3 connects the operation cabin 1 and the jetting frame 2, the position of the jetting frame 2 relative to the operation cabin 1 is flexibly adjusted and locked by screwing the adjusting bolt 3.

[0050] The operation cabin 1 adopts the fixed-point jet scouring method, which specifically comprises the following steps: the working mother ship stays near the operation seabed area, the jet scouring frame 2 is installed in the operation cabin 1, and the distance between the combined nozzle 4 and the bottom surface of the operation cabin 1 is adjusted to 10 mm, the distance between the combined nozzle 4 and the bottom surface of the operation cabin 1 is determined according to the jet scouring pressure and the jet scouring speed; the dredging pump 5 and the combined nozzle 4 are alternately installed on the jet scouring frame 2, the combined nozzle 4 is connected with the jet scouring pipeline 7, the dredging pump 5 is connected with the sludge discharge pipeline 8, and the jet scouring pipeline 7 and the sludge discharge pipeline 8 are both connected with the working mother ship; the working mother ship lowers the operation cabin 1 to the operation seabed area through the hoisting device, the jet scouring liquid is input into the combined nozzle 4 through the jet scouring pipeline 7 and is jetted out at high speed through the combined nozzle 4, the silt at the position of the operation seabed area is jetted and scattered, at the same time, the dredging pump 5 is started, the dredging pump 5 sucks the silt and discharges the silt out of the operation seabed area through the sludge discharge pipeline 8, the working mother ship slowly lowers the operation cabin 1 through the hoisting device until the whole operation seabed area is jetted and scoured, the silt at the position near the wellhead is cleaned, the wellhead is connected back, and the operation cabin 1 is lifted through the hoisting device until it leaves the operation seabed area.

[0051] It should be noted that the distance between the combined nozzle 4 and the bottom surface of the operation cabin 1, that is, the jet scouring target distance, the setting of the jet scouring target distance can produce the greatest impact force and impact area of the jet scouring liquid jetted out of the nozzle 403 on the silt, the jet scouring target distance is determined through simulation analysis and calculation according to the jet scouring pressure and the jet scouring speed, the installation height of the combined nozzle 4 relative to the bottom surface of the operation cabin 1 is determined before the operation cabin 1 is hoisted to the operation seabed area, and the construction efficiency is effectively improved.

[0052] In summary, the jet scouring liquid is input into the combined nozzle 4 through the jet scouring pipeline 7 and is jetted out at high speed through the combined nozzle 4, the silt at the position of the operation seabed area is directly jetted and scattered, at the same time, the silt is sucked through the dredging pump 5 and is discharged out of the operation seabed area through the sludge discharge pipeline 8, manual local dredging is no longer needed, the operation cost is effectively reduced, and the silt jet scouring efficiency is improved. Moreover, there is no need to worry about the risk of silt backfilling and pit collapse, and the safety during operation is effectively improved.

[0053] It should be noted that in the present specification, the relationship terms such as first and second are only used to distinguish one entity from another entity, and do not necessarily require or imply any such actual relationship or order between the entities.

[0054] The principles and implementation modes of the present application are described by applying specific examples in the present document, and the above description of the examples is only used to help understand the method of the present application and its core idea. It should be pointed out that, for ordinary skilled persons in the technical field, some improvements and modifications can be made to the present application without departing from the principles of the present application, and these improvements and modifications also fall within the protection scope of the present application.

Claims

1. A fixed-point jetting and scouring device for a work cabin, characterized by, The utility model relates to a kind of work cabin, including: Work cabin; Spray frame, the inner wall of the work cabin is connected by adjusting bolt, a plurality of combination nozzles are provided on the spray frame, a plurality of combination nozzles are connected spray pipeline respectively, and the spray pipeline is used to input spray liquid to the combination nozzle; Dredge pump, a plurality of dredge pumps are arranged on the spray frame, and a plurality of dredge pumps are connected mud pipeline respectively, and the mud pipeline is used to discharge the silt inhaled by the dredge pump.

2. The device according to claim 1, characterized in that, The combination nozzle includes: nozzle passage, the first end of the nozzle passage is threadedly connected with the spray pipeline, and the second end of the nozzle passage is arrayed with a plurality of nozzles.

3. A fixed-point jetting and scouring device for a work cabin according to claim 2, characterized in that, The angle between the axis of the nozzle and the axis of the nozzle passage is between 10-30°, and the axis of one of the nozzles coincides with one of the radius sections of the spray frame.

4. A fixed-point jetting device for a work cabin according to any one of claims 1 to 3, characterized in that, The spray frame includes: a lower ring, the top of the lower ring is connected with a plurality of vertical supports, and the upper end of the vertical support is connected with an upper ring.

5. A spot blast device for a work chamber as claimed in claim 4, wherein, The inner side of the lower ring is coaxially provided with an inner ring, and the lower ring is connected with the inner ring through a connecting rod.

6. A spot blast device for a work chamber as claimed in claim 5, wherein, The inner ring is arranged directly above the wellhead, and the diameter of the inner ring is greater than the maximum projection size of the wellhead and leaves a working space.

7. A spot blast device for a work chamber as claimed in claim 6, wherein, The work cabin and the spray frame are coaxially arranged, and the distance between the inner side wall of the work cabin and the outer side wall of the spray frame is between 5-20mm.

8. A spot blast device for a work chamber according to any one of claims 1-3, characterized in that, The suction nozzle is provided on the dredge pump, the first end of the suction nozzle is provided with a fixed plate, the fixed plate is connected with the spray frame, and the second end of the suction nozzle is in the shape of a cone as a whole.

9. A method of spot blasting of a work chamber of a spot blasting device according to any one of claims 1-8, characterized in that, The utility model relates to a kind of work cabin, including: S1: install spray frame in work cabin, and adjust the distance between the combination nozzle and the bottom surface of the work cabin;Dredge pump and combination nozzle are alternately installed on the spray frame, combination nozzle is connected with spray pipeline, dredge pump is connected with mud pipeline, and spray pipeline and mud pipeline are connected with working mother ship; S2: the working mother ship is placed in the work seabed area by hoisting device, and the spray liquid is input into the combination nozzle through the spray pipeline and is sprayed at high speed through the combination nozzle, while starting dredge pump, and the dredge pump inhaled silt is discharged from the work seabed area through the mud pipeline; S3: the working mother ship is slowly lowered by hoisting device until the whole work seabed area is sprayed, and the wellhead is connected back, and the work cabin is lifted by hoisting device until it leaves the work seabed area.

10. The method according to claim 9, wherein, before the step of installing the spray frame in the work cabin, further comprising: determining the distance between the combination nozzle and the bottom surface of the work cabin by simulation analysis and calculation according to the spray pressure and the spray speed. ​

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