Mud tank structure for preventing sand setting at four corners of mud tank and design method
By installing a stirring unit and a turbulence unit inside the mud tank, the problem of sand settling at the four corners of the rectangular mud tank was solved, improving storage efficiency and drilling fluid performance, and reducing cleaning difficulty.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA NAT PETROLEUM CORP
- Filing Date
- 2024-10-30
- Publication Date
- 2026-05-01
AI Technical Summary
In traditional rectangular mud tanks, solid particles in the mud tend to accumulate in the four corners of the tank during use, affecting storage efficiency and the normal progress of drilling operations, and increasing the labor intensity and safety risks of cleaning.
Design a structure to prevent sand settling at the four corners of a mud tank, including setting up a stirring unit and a turbulence unit inside the tank. The stirring unit realizes a swirling flow field through a stirring shaft and stirring blades, and the turbulence unit improves fluidity and reduces solid phase settling through turbulence baffles and flow holes.
It effectively solved the problem of sand settling in the four corners of the mud tank, improved volumetric efficiency, enhanced drilling fluid performance, and reduced cleaning labor intensity.
Smart Images
Figure CN121947966A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of drilling engineering technology and equipment, and in particular to a mud tank structure and design method for preventing sand from settling at the four corners of the mud tank. Background Technology
[0002] In drilling and oilfield development, mud tanks are critical equipment used to store and process drilling mud. However, in traditional rectangular mud tanks, due to the flow characteristics of the mud and gravity, solid particles in the mud tend to accumulate in the four corners. This accumulation not only affects the storage efficiency of the mud tank but also leads to a decline in mud performance, hindering normal drilling operations. Furthermore, during well crew relocation, the accumulated sediment in the corners increases the labor intensity and safety risks associated with cleaning.
[0003] To reduce sediment buildup at the bottom of mud tanks, domestic drilling companies and manufacturers have made numerous attempts to improve tank structure. However, constrained by factors such as well site area, transportation conditions, and manufacturing costs, rectangular tanks are currently the dominant structure in major oilfields in China. Rectangular mud tanks offer large volume, simple structure, and low manufacturing and transportation costs, making them a relatively economical option. Therefore, in-depth research and optimization of the rectangular tank structure and flow field to reduce sediment buildup can better leverage the advantages of rectangular tanks.
[0004] Based on this, it is necessary to develop a structure and design method for a mud tank that prevents sand settling at four corners. This invention effectively solves the problem of sand settling at four corners of traditional rectangular mud tanks through fluid-structure interaction finite element simulation, tank structure optimization, and other methods. Summary of the Invention
[0005] The technical problem to be solved by the present invention is to provide a mud tank structure and design method for preventing sand from settling at the four corners of the mud tank, which effectively overcomes the defects of the prior art.
[0006] The technical solution of the present invention to solve the above-mentioned technical problems is as follows:
[0007] A mud tank structure for preventing sand settling at the four corners includes a rectangular tank body with a tank cover on the top. A stirring unit extending downward to near the bottom of the tank is provided in the central area of the tank body. A power device connected to and driving the stirring unit to rotate is provided on the tank cover. At least two vertically extending turbulence units are provided at intervals along the length direction on the inner side of each of the four side walls of the tank body.
[0008] Based on the above technical solution, the present invention can be further improved as follows.
[0009] Furthermore, the aforementioned stirring unit includes a stirring shaft and stirring blades. The stirring shaft is vertically arranged, with its lower end connected to the stirring blades and its upper end connected to the power unit.
[0010] Furthermore, the aforementioned turbulence unit includes a strip-shaped turbulence baffle, and the turbulence baffle is provided with transversely penetrating flow holes at even intervals at its top and bottom.
[0011] Furthermore, the lower end of the aforementioned baffle contacts the bottom of the tank, and the lower end of the aforementioned baffle is provided with an arc-shaped notch.
[0012] Furthermore, the aforementioned baffle is vertically fixed to the inner wall of the tank.
[0013] Furthermore, the cross-sectional shape of the aforementioned baffle is designed as a symmetrical arc.
[0014] Furthermore, the inner wall of the tank is provided with a vertically extending T-shaped groove, and the side end of the baffle is provided with a T-shaped block that is adapted to the T-shaped groove. The T-shaped block is embedded into the T-shaped groove from top to bottom.
[0015] Furthermore, the turbulence-disrupting units on each side wall of the tank are equally distributed along the side length of that side wall.
[0016] Furthermore, the aforementioned flow passage is a circular hole.
[0017] The beneficial effects are: the structural design is simple and reasonable, which can effectively improve the mud flow state at the four corners of the mud tank, reduce solid sedimentation, effectively solve the problem of sand settling at the four corners that is common in traditional rectangular mud tanks during use, improve the volumetric efficiency of the mud tank, enhance the performance of drilling fluid, and reduce the labor intensity of cleaning the mud tank.
[0018] A design method for a mud tank structure to prevent sand settling at the four corners is also provided, including the following steps:
[0019] Step 1: Establish a cuboid mud tank, agitator, and fluid-structure interaction finite element model of the mud, and set the size and density parameters of the solid particles in the mud.
[0020] Step 2: Simulate the flow field distribution during the mud mixing process in the mud tank on the model;
[0021] Step 3: Arrange turbulence baffles in the mud tank, re-simulate the flow field distribution, and compare the flow field distribution near the four corners of the mud tank.
[0022] Step 4: Adjust the distribution and orientation of the baffles until the solid particles near the four corners of the mud tank settle to the minimum, and determine the installation position and quantity distribution of the baffles.
[0023] Step 5: Install and modify the baffles inside the mud tank according to the distribution determined in Step 4.
[0024] The beneficial effects are: the design method is simple and easy to implement. Attached Figure Description
[0025] Figure 1 This is a three-dimensional structural view of the mud tank structure for preventing sand settling at the four corners of the mud tank according to the present invention.
[0026] Figure 2 A side view of the structure of the mud tank with anti-sand settling at the four corners of the mud tank according to the present invention. Figure 1 ;
[0027] Figure 3 A side view of the structure of the mud tank with anti-sand settling at the four corners of the mud tank according to the present invention. Figure 2 ;
[0028] Figure 4 This is a top view of the structure of the mud tank with anti-sand settling at the four corners of the mud tank according to the present invention;
[0029] Figure 5 This is a partial structural diagram of the connection between the turbulence baffle and the tank body in the mud tank structure for preventing sand settling at the four corners of the mud tank according to the present invention.
[0030] Figure 6 This is a diagram showing the distribution of sediment inside the mud tank before modification, which is involved in the design method of the mud tank structure for preventing sediment settling at the four corners of the mud tank according to the present invention.
[0031] Figure 7 This is a diagram showing the distribution of sediment inside the modified mud tank, which is part of the design method for the mud tank structure to prevent sediment settling at the four corners of the mud tank according to the present invention.
[0032] Figure 8 This is a comparison diagram of the bottom sand distribution model of the mud tank before and after modification, which is involved in the design method of the mud tank structure for preventing sand settling at the four corners of the mud tank according to the present invention.
[0033] Figure 9 The flow field distribution diagrams at the bottom of the mud tank before and after modification are shown in the design method of the mud tank structure for preventing sand settling at the four corners of the mud tank according to the present invention.
[0034] Figure 10 The diagram shows the internal flow field distribution of the mud tank before and after modification, which is part of the design method for the mud tank structure to prevent sand settling at the four corners of the mud tank according to the present invention.
[0035] The attached diagram lists the components represented by each number as follows:
[0036] 1. Tank body; 2. Stirring unit; 31. Baffle; 311. Flow hole. Detailed Implementation
[0037] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.
[0038] Example 1
[0039] like Figures 1 to 5 As shown, the mud tank structure with four corners settling sand in this embodiment includes a rectangular tank body 1. The top of the tank body 1 is provided with a tank cover. The central area of the tank body 1 is provided with a stirring unit 2 extending downward to near the bottom of the tank. The tank cover is provided with a power device A connected to the stirring unit 2 and driving it to rotate. At least two vertically extending turbulence units are provided at intervals along the length direction on the inner side of each of the four side walls of the tank body 1.
[0040] The mud tank structure of this embodiment, which prevents sand settling at the four corners of the mud tank, has vertically extending turbulence units on the inner surface of the four side walls of the tank body 1. During the stirring process of the stirring unit 2, the internal slurry generates a swirling flow field centered on the stirring unit 2. When the outer periphery of the flow field comes into contact with the turbulence units, eddies are generated locally, which plays a turbulence role. Since there are at least two turbulence units distributed on each of the four side walls, the overall effect is to turbulent the flow field around the periphery, thereby improving the dynamics of the slurry at the four corners of the rectangular mud tank, reducing solid sedimentation, and thus improving the problem of severe sand settling at the four corners of the existing rectangular mud tank, which affects the volumetric efficiency of the mud tank, leads to a decline in mud performance, and increases the labor intensity of cleaning the mud tank.
[0041] In this embodiment, the stirring unit 2 includes a stirring shaft and stirring blades. The stirring shaft is vertically arranged, with its lower end connected to the stirring blades and its upper end connected to the power unit. At least three stirring blades are used, each connected to the lower end of the stirring shaft. The power unit can be a conventional, commercially available, compatible motor.
[0042] In a preferred embodiment, the aforementioned turbulence unit includes a strip-shaped turbulence baffle 31, wherein the turbulence baffle 31 is provided with transversely penetrating flow holes 311 evenly spaced vertically.
[0043] In the above implementation scheme, the design of the flow hole 311 can reduce the impact force when the slurry impacts the baffle 31, allowing it to pass through well without forming deposits or blockages at the baffle 31.
[0044] In this embodiment, the lower end of the aforementioned baffle 31 contacts the bottom of the tank, and the lower end of the baffle 31 is provided with an arc-shaped notch B. This design allows the baffle 31 to cover the slurry flow at the bottom of the tank. At the same time, the notch design allows the slurry at the bottom of the tank to pass through better when impacting the baffle 31, avoiding deposition and obstruction at this location.
[0045] In this embodiment, the aforementioned baffle 31 is vertically fixed to the inner wall of the tank 1, and this design achieves the best turbulence effect.
[0046] In this embodiment, the cross-sectional shape of the two sides of the aforementioned baffle 31 is set as a symmetrical arc. The arc design makes the contact between the slurry and the side of the baffle 31 in an arc shape, reducing the impact force.
[0047] In a preferred embodiment, the inner wall of the tank 1 is provided with a vertically extending T-shaped groove, and the side end of the baffle 31 is provided with a T-shaped block adapted to the T-shaped groove, and the T-shaped block is embedded in the T-shaped groove from top to bottom.
[0048] In the above implementation scheme, the baffle 31 is assembled on the inner wall of the tank 1 by a plug-in method, which is convenient for disassembly and replacement.
[0049] In this embodiment, the turbulence-dispersing units on each side wall of the tank 1 are equally distributed along the side length of that side wall. The turbulence-dispersing units are equally distributed between the two ends on each side wall, ensuring that a relatively uniform turbulence effect can be achieved around the mud tank.
[0050] In this embodiment, the flow passage 311 is a round hole, which has good flow effect and low resistance.
[0051] Example 2
[0052] The design method of the mud tank structure with anti-sand settling at the four corners in this embodiment includes the following steps:
[0053] Step 1: Establish a cuboid mud tank, agitator, and fluid-structure interaction finite element model of the mud, and set the size and density parameters of the solid particles in the mud.
[0054] Step 2: Simulate the flow field distribution during the mud mixing process in the mud tank on the model;
[0055] Step 3: Arrange turbulence baffles 31 in the mud tank, re-simulate the flow field distribution, and compare the flow field distribution near the four corners of the mud tank.
[0056] Step 4: Adjust the distribution and orientation of the baffles 31 until the solid particles near the four corners of the mud tank settle to the minimum, and determine the installation position and quantity distribution of the baffles 31.
[0057] Step 5: Install and modify the turbulence baffles 31 inside the mud tank according to the distribution determined in Step 4.
[0058] It should be noted that in step one of this embodiment, Fluent, a technology based on existing technology, is used for coupled modeling with EDEM software.
[0059] More specifically, such as Figure 6As shown, without the turbulence unit of this embodiment, the deposition is not obvious in a very small area around the stirring unit 2, but the solid phase deposition is greater closer to the bottom of the tank in other areas. After the turbulence unit is installed (e.g., Figure 7 As shown in the figure, this phenomenon has been greatly improved, and the solid phase deposition around the stirring unit 2 and even to the side wall of the mud tank is not obvious. Figure 8 As shown, before the installation of the turbulence unit, the simulation showed almost no solid phase deposition in a very small area around the stirring unit 2 inside the mud tank, but a significant solid phase deposition phenomenon (sand settling) was observed in the larger outer area. After the installation of the turbulence unit, the solid phase deposition phenomenon between the outer edge of the turbulence unit and the side wall of the mud tank was significantly improved, with only very small deposition phenomena at the turbulence unit itself. Figure 9 As shown, before the installation of the turbulence unit, during the mixing process of the stirring unit 2, the flow field distribution was almost non-existent at the four corners of the mud tank. After the installation of the turbulence unit, the flow field almost covered the entire mud tank, including the four corners. Figure 10 As shown, before the installation of the turbulence unit, the flow field was relatively concentrated in a small area around the mixing unit 2, and the fluidity was relatively high. After the installation of the turbulence unit, the flow field distribution in a larger area around the mixing unit 2 was significantly improved, and the fluidity of the slurry in the larger area was better.
[0060] The mud tank structure and design method for preventing sand accumulation at the four corners, as described in this embodiment, effectively solves the common problem of sand accumulation at the four corners in traditional rectangular mud tanks during use. This improves the volumetric efficiency of the mud tank, enhances drilling fluid performance, and reduces the labor intensity of mud tank cleaning. This structure and design method can be used to upgrade existing mud tanks in oilfields; it is easy to implement, has low modification costs, and can also be used in the design of new tanks, demonstrating high practicality and promotional value.
[0061] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.
[0062] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0063] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0064] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.
[0065] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.
[0066] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.
Claims
1. A mud tank structure for preventing sand settling at the four corners of the mud tank, characterized in that: The container includes a rectangular tank (1), with a lid on top. A stirring unit (2) extending downward to near the bottom of the tank is located in the central area of the tank (1). A power device connected to and driving the stirring unit (2) to rotate is provided on the lid. At least two vertically extending turbulence units are provided at intervals along the length direction on the inner sides of the four side walls of the tank (1).
2. The mud tank structure for preventing sand settling at the four corners of the mud tank according to claim 1, characterized in that: The stirring unit (2) includes a stirring shaft and stirring blades. The stirring shaft is arranged vertically, with its lower end connected to the stirring blades and its upper end connected to the power device.
3. The mud tank structure for preventing sand settling at the four corners of the mud tank according to claim 1, characterized in that: The turbulence unit includes a strip-shaped turbulence baffle (31), and the turbulence baffle (31) is provided with transverse through holes (311) evenly spaced vertically.
4. The mud tank structure for preventing sand settling at the four corners of the mud tank according to claim 3, characterized in that: The lower end of the baffle (31) contacts the bottom of the tank, and the lower end of the baffle (31) is provided with an arc-shaped notch.
5. The mud tank structure for preventing sand settling at the four corners of the mud tank according to claim 3, characterized in that: The baffle (31) is vertically fixed to the inner wall of the tank (1).
6. The mud tank structure for preventing sand settling at the four corners of the mud tank according to claim 3, characterized in that: The cross-sectional shape of the two sides of the turbulence baffle (31) is set as a symmetrical arc.
7. The mud tank structure for preventing sand settling at the four corners of the mud tank according to claim 3, characterized in that: The inner wall of the tank (1) is provided with a vertically extending T-shaped groove, and the side end of the baffle (31) is provided with a T-shaped block that is adapted to the T-shaped groove. The T-shaped block is embedded in the T-shaped groove from top to bottom.
8. The mud tank structure for preventing sand settling at the four corners of the mud tank according to claim 3, characterized in that: The turbulence units on each side wall of the tank (1) are equally distributed along the side length of that side wall.
9. The mud tank structure for preventing sand settling at the four corners of the mud tank according to claim 3, characterized in that: The flow passage (311) is a round hole.
10. A design method for a mud tank structure with anti-sand settling at the four corners as described in any one of claims 1 to 9, characterized in that, Includes the following steps: Step 1: Establish a cuboid mud tank, agitator, and fluid-structure interaction finite element model of the mud, and set the size and density parameters of the solid particles in the mud. Step 2: Simulate the flow field distribution during the mud mixing process in the mud tank on the model; Step 3: Arrange turbulence baffles (31) in the mud tank, re-simulate the flow field distribution, and compare the flow field distribution near the four corners of the mud tank. Step 4: Adjust the distribution and orientation of the baffles (31) until the solid particles near the four corners of the mud tank settle to the minimum, and determine the installation position and quantity distribution of the baffles (31). Step 5: Install and modify the turbulence baffles (31) in the mud tank according to the distribution determined in Step 4.