Slurry mixing system and control method thereof, storage medium and controller

Abstract

The invention belongs to the field of hydraulic devices, and discloses a slurry mixing system and a control method thereof, a storage medium and a controller. The slurry mixing system comprises a hydraulic loop, a throttling flow path and a switching device; a motor and an oil pump are arranged on the hydraulic loop; a throttling valve is arranged on the throttling flow path; a throttling valve is arranged on the throttling flow path; and the switching device switches the outlet of the motor to be communicated with the throttling flow path or the inlet of the oil pump. After the collision pressure phenomenon occurs, the oil pump is controlled to stop supplying oil, oil driven by the motor is guided to the throttling flow path through the switching device, the situation that the oil pump is damaged due to the fact that the oil drives the oil pump is avoided, the oil output by the motor is adjusted step by step through the throttling valve, and therefore the oil supply speed is increased. The motor gradually stops rotating until stopping, oil pump damage caused by sudden closing of the oil pump is avoided, and pipeline damage caused by excessive pressure in the slurry pipeline due to excessive output of slurry is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of hydraulic devices, and in particular to a slurry mixing system and a control method, a storage medium and a controller thereof. Background Art

[0002] The hydraulically driven cementing truck uses a closed hydraulic system to drive the large pump. The start and stop of the large pump is achieved by controlling the on and off of the current by the oil pump. During cementing operations, if the pipeline is "pressurized", the large pump must be manually stopped as soon as possible to prevent damage due to excessive pressure in the pipeline. However, manual pump stop requires high experience from the operator, and when the oil pump is stopped instantly, the mud pump will still rotate due to inertia and become the power of the motor, causing the oil pressure flowing from the motor to the oil pump to increase, bringing huge pressure shocks and reducing the life of components and pipelines. Summary of the invention

[0003] The main purpose of the present invention is to provide a slurry mixing system and its control method, storage medium, and controller, aiming to solve the problem that stopping the pump in the slurry mixing system during pressure collision will cause excessive impact.

[0004] To achieve the above object, the present invention provides a slurry mixing system, comprising:

[0005] A hydraulic circuit, wherein a motor and an oil pump are provided on the hydraulic circuit;

[0006] a throttling flow path, wherein a throttling valve is provided on the throttling flow path; and

[0007] A switching device switches the outlet of the motor to be connected to the throttling flow path or the inlet of the oil pump.

[0008] Optionally, the switching device includes a reversing valve, which includes a first valve port, a second valve port and a third valve port. The first valve port is connected to the inlet of the oil pump, the second valve port is connected to the outlet of the motor, and the third valve port is connected to the throttling flow path. The second valve port can be switched to connect to the first valve port or the third valve port.

[0009] Optionally, the slurry mixing system further includes a mud pump drivingly connected to the motor.

[0010] Optionally, the slurry mixing system further comprises an overflow flow path, an overflow valve is provided on the overflow flow path, the overflow flow path is connected to the throttling flow path, and is connected between the throttling valve and the switching device.

[0011] The present invention further provides a control method for a slurry mixing system, including the slurry mixing system according to any one of the above, the control method for the slurry mixing system comprising:

[0012] Determining the maximum working pressure of the motor, and determining the impact pressure according to the maximum working pressure;

[0013] After the cementing operation starts, the real-time outlet pressure of the oil pump and the real-time working pressure of the motor are obtained;

[0014] When the real-time outlet pressure is greater than the impact pressure, the oil pump is controlled to stop supplying oil, and the switching device is controlled to switch the throttling flow path to connect to the outlet of the motor;

[0015] According to the real-time well pipe pressure in the well pipe, the opening of the throttle valve is reduced until it is closed.

[0016] Optionally, reducing the opening of the throttle valve until it is closed according to the real-time wellbore pressure in the wellbore includes:

[0017] In the process that the real-time well pipe pressure rises from the impact pressure to the first preset pressure, the opening of the throttle valve is reduced until it is closed.

[0018] Optionally, after starting the cementing operation and obtaining the real-time outlet pressure of the oil pump and the real-time working pressure of the motor, the method further includes:

[0019] Determining an adjustment trigger pressure according to the maximum working pressure;

[0020] When the real-time outlet pressure is greater than the adjustment trigger pressure, the power of the oil pump is reduced until the real-time outlet pressure is less than or equal to the adjustment trigger pressure.

[0021] Optionally, after starting the cementing operation and obtaining the real-time outlet pressure of the oil pump and the real-time working pressure of the motor, the method further includes:

[0022] Obtaining a preset target flow rate of the slurry mixing system and a cumulative flow rate of the mud pump;

[0023] Determining an adjustment trigger flow rate according to the preset target flow rate;

[0024] When the accumulated flow is greater than the adjustment trigger flow, the displacement of the mud pump is reduced to be less than or equal to a preset displacement.

[0025] The present invention further provides a storage medium, characterized in that a control program of a slurry mixing system is stored on the storage medium, and when the control program of the slurry mixing system is executed by a processor, the control method of the slurry mixing system as described in any one of the above items is implemented.

[0026] The present invention also provides a controller, characterized in that the controller includes a memory and a processor, and a control program of a mixing system stored in the memory and run on the processor, and the control program of the mixing system is configured to implement the steps of the control method of the mixing system as described in any one of the above.

[0027] The present invention provides a slurry mixing system, wherein the motor and the oil pump are hydraulically driven through the hydraulic circuit, the oil pump supplies oil to the motor to drive the motor to rotate, and the throttling flow path is switched between the inlet of the oil pump and the outlet of the motor through the switching device. After the collision and pressure phenomenon occurs, the oil pump is controlled to stop supplying oil. Due to the action of the mud, the motor will continue to rotate. At this time, the oil in the hydraulic circuit will continue to flow toward the oil pump, and the oil driven by the motor is guided to the throttling flow path through the switching device to avoid the oil driving the oil pump and causing damage to the oil pump. At the same time, the throttle valve gradually adjusts the oil output by the motor so that the motor gradually stops rotating until it stops, avoiding damage to the oil pump caused by suddenly shutting down the oil pump, and the motor can be gradually stopped to avoid excessive output of mud causing excessive pressure in the mud pipeline to damage the pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the connection structure of the slurry mixing system provided by the embodiment of the present invention;

[0029] Figure 2 It is a flowchart of a control method for a slurry mixing system provided by an embodiment of the present invention.

[0030] Description of Figure Numbers:

[0031] 100. Mixing system; 11. Motor; 12. Oil pump; 21. Throttle valve; 3. Switching device; 41. Mud pump; 51. Overflow valve.

[0032] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0035] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in the field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0036] See also Figure 1 The present invention provides a slurry mixing system 100, including a hydraulic circuit, a throttling flow path and a switching device 3; the hydraulic circuit is provided with a motor 11 and an oil pump 12; the throttling flow path is provided with a throttle valve 21; the switching device 3 switches the outlet of the motor 11 to be connected to the throttling flow path 21 or the inlet of the oil pump 12.

[0037] The present invention provides a slurry mixing system 100, wherein the motor 11 and the oil pump 12 are hydraulically driven through the hydraulic circuit, the oil pump 12 supplies oil to the motor 11 to drive the motor 11 to rotate, and the throttling flow path is switched between the inlet of the oil pump 12 and the outlet of the motor 11 through the switching device 3. After the collision and pressure phenomenon occurs, the oil pump 12 is controlled to stop supplying oil. Due to the action of the mud, the motor 11 will continue to rotate. At this time, the oil in the hydraulic circuit will continue to flow toward the oil pump 12, and the oil driven by the motor 11 is guided to the throttling flow path through the switching device 3 to avoid the oil driving the oil pump 12 and causing damage to the oil pump 12. At the same time, the throttle valve 21 gradually adjusts the oil output of the motor 11 so that the motor 11 gradually stops rotating until it stops, avoiding damage to the oil pump caused by suddenly shutting down the oil pump 12, and can gradually stop the motor 11 to avoid excessive output of mud causing excessive pressure in the mud pipeline to damage the pipeline.

[0038] It should be noted that the switching device 3 has multiple implementations, such as a valve group composed of multiple switch valves, which respectively control the on-off of the outlet and inlet of the motor 11 and the oil pump 12, and the channel of the throttling flow path, so as to connect the throttling flow path to the outlet of the motor 11.

[0039] Specifically, in this embodiment, the switching device 3 includes a reversing valve, and the reversing valve includes a first valve port, a second valve port, and a third valve port. The first valve port is connected to the inlet of the oil pump 12, the second valve port is connected to the outlet of the motor 11, and the third valve port is connected to the throttling flow path. The second valve port can be switched to be connected to the first valve port or the third valve port. In this embodiment, the switching between the flow paths is carried out in the form of a three-way valve, which is simple to operate, and the on-off control of the flow path can be realized while the control circuit is on and off. The structure is simple and reliable.

[0040] Furthermore, the slurry mixing system 100 further includes a mud pump 41 drivingly connected to the motor 11. In this embodiment, the mud pump 41 is driven to rotate by the motor 11 to facilitate the transportation of mud.

[0041] On the other hand, the slurry mixing system 100 also includes an overflow flow path, on which an overflow valve 51 is provided, and the overflow flow path is connected to the throttle flow path, and is connected between the throttle valve 21 and the switching device 3. In this embodiment, after the throttle valve 21 is connected to the hydraulic circuit, it will gradually close until the throttle flow path is disconnected. In order to avoid the hydraulic shock caused by the continued activity of the motor 11 at this time, an overflow flow path is connected between the throttle valve and the switching device 3, and an overflow valve 51 is provided on the overflow flow path. At the disconnection port of the throttle flow path, if the motor 11 continues to deliver oil, at this time, pressure will be accumulated at the throttle valve until the overflow valve 51 opens after reaching a preset pressure value to release the oil, thereby avoiding damage to the motor 11 and the throttle valve.

[0042] Based on the above-mentioned slurry mixing system, the present invention also provides a controller of the slurry mixing system. Further, in an embodiment of the present invention, the controller includes a memory, a processor, and a control program of the slurry mixing system stored in the memory. The processor executes the control program of the slurry mixing system to implement the following control method of the slurry mixing system:

[0043] Determining the maximum working pressure of the motor, and determining the impact pressure according to the maximum working pressure;

[0044] After the cementing operation starts, the real-time outlet pressure of the oil pump and the real-time working pressure of the motor are obtained;

[0045] When the real-time outlet pressure is greater than the impact pressure, the oil pump is controlled to stop supplying oil, and the switching device is controlled to switch the throttling flow path to connect to the outlet of the motor;

[0046] According to the real-time well pipe pressure in the well pipe, the opening of the throttle valve is reduced until it is closed.

[0047] Optionally, reducing the opening of the throttle valve until it is closed according to the real-time wellbore pressure in the wellbore includes:

[0048] In the process that the real-time well pipe pressure rises from the impact pressure to the first preset pressure, the opening of the throttle valve is reduced until it is closed.

[0049] Optionally, after starting the cementing operation and obtaining the real-time outlet pressure of the oil pump and the real-time working pressure of the motor, the method further includes:

[0050] Determining an adjustment trigger pressure according to the maximum working pressure;

[0051] When the real-time outlet pressure is greater than the adjustment trigger pressure, the power of the oil pump is reduced until the real-time outlet pressure is less than or equal to the adjustment trigger pressure.

[0052] The present invention further provides a control method for a slurry mixing system, including the above-mentioned slurry mixing system 100, and the control method for the slurry mixing system includes:

[0053] S10, determining the maximum working pressure of the motor, and determining the impact pressure according to the maximum working pressure;

[0054] In this embodiment, the maximum working pressure of the motor 11 is first determined, thereby determining the collision pressure when collision pressure occurs in the pipeline, so as to protect the normal operation of the motor 11.

[0055] It should be noted that the step of determining the maximum working pressure of the motor includes determining the maximum working pressure of the motor according to the rated pressure of the well pipe in which the slurry mixing system works, so as to ensure the safety of the well pipe.

[0056] S20, after starting the cementing operation, obtaining the real-time outlet pressure of the oil pump and the real-time working pressure of the motor;

[0057] After the cementing operation starts, the oil pump starts to work to deliver oil to the inlet of the motor, driving the motor to start working. At this time, it is necessary to monitor the outlet pressure of the oil pump and the working pressure of the motor in real time to determine whether a collision pressure occurs.

[0058] S30, when the real-time outlet pressure is greater than the impact pressure, controlling the oil pump to stop supplying oil, and controlling the switching device to switch the throttling flow path to connect to the outlet of the motor;

[0059] Once the real-time outlet pressure is greater than the bump pressure, it indicates that the oil pump encounters an obstruction when driving the motor to work, causing the pressure at the oil pump outlet to increase. When the real-time outlet pressure of the oil pump is greater than the bump pressure, it indicates that a bump pressure has occurred.

[0060] Wherein, the impact pressure is 0.75 times of the maximum working pressure.

[0061] S40, reducing the opening of the throttle valve until it is closed according to the real-time well pipe pressure in the well pipe.

[0062] After the real-time outlet pressure is greater than the impact pressure, although the oil pump is turned off, the motor continues to rotate, causing the oil to flow to the throttling path. By gradually reducing the opening of the throttle valve until it is closed, the motor gradually reduces its speed and is completely closed, so that the motor no longer drives the mud in the well pipe to flow, thereby protecting the pressure safety in the well pipe.

[0063] Further, step S40 includes:

[0064] S40, when the real-time wellbore pressure increases from the impact pressure to the first preset pressure, reducing the opening of the throttle valve until it is closed.

[0065] In this embodiment, when the real-time wellbore pressure reaches the impact pressure, the throttle valve starts to close, and the throttle valve is closed after the real-time wellbore pressure reaches the first preset pressure.

[0066] It should be noted that the first preset pressure is 0.91 times the maximum working pressure.

[0067] On the other hand, after step S20, the method further includes:

[0068] S01. determining an adjustment trigger pressure according to the maximum working pressure;

[0069] S02. When the real-time outlet pressure is greater than the adjustment trigger pressure, reducing the power of the oil pump until the real-time outlet pressure is less than or equal to the adjustment trigger pressure.

[0070] In this embodiment, after the cementing operation starts, the adjustment trigger pressure is determined. Once the real-time outlet pressure is greater than the adjustment trigger pressure, the power of the oil pump is reduced, the mud delivery volume in the well pipe is reduced, and the risk of collision pressure is reduced.

[0071] On the other hand, after step S20, the method further includes:

[0072] S03, obtaining a preset target flow rate of the slurry mixing system and a cumulative flow rate of the mud pump;

[0073] S04, determining an adjustment trigger flow rate according to the preset target flow rate;

[0074] S05. When the accumulated flow is greater than the adjustment trigger flow, the displacement of the mud pump is reduced to be less than or equal to a preset displacement.

[0075] When the actual cumulative flow of cement slurry reaches 90% of the theoretical cumulative demand value, the control system automatically adjusts the displacement of the mud pump to no more than 0.5 cubic meters per minute to avoid large displacement collision.

[0076] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A slurry mixing system, characterized in that: include: A hydraulic circuit, wherein a motor and an oil pump are provided on the hydraulic circuit; A throttling flow path, wherein a throttling valve is provided on the throttling flow path; as well as, A switching device switches the outlet of the motor to be connected to the throttling flow path or the inlet of the oil pump.

2. The slurry mixing system according to claim 1, characterized in that: The switching device includes a reversing valve, which includes a first valve port, a second valve port and a third valve port. The first valve port is connected to the inlet of the oil pump, the second valve port is connected to the outlet of the motor, and the third valve port is connected to the throttling flow path. The second valve port can be switched to be connected to the first valve port or the third valve port.

3. The slurry mixing system according to claim 1, characterized in that: The slurry mixing system also includes a mud pump drivingly connected to the motor.

4. The slurry mixing system according to claim 1, characterized in that: The slurry mixing system further comprises an overflow flow path, an overflow valve is arranged on the overflow flow path, the overflow flow path is connected to the throttling flow path, and is connected between the throttling valve and the switching device.

5. A control method for a slurry mixing system, characterized in that: The invention comprises a slurry mixing system according to any one of claims 1 to 4, wherein the control method of the slurry mixing system comprises: Determining the maximum working pressure of the motor, and determining the impact pressure according to the maximum working pressure; After the cementing operation starts, the real-time outlet pressure of the oil pump and the real-time working pressure of the motor are obtained; When the real-time outlet pressure is greater than the impact pressure, the oil pump is controlled to stop supplying oil, and the switching device is controlled to switch the throttling flow path to connect to the outlet of the motor; According to the real-time well pipe pressure in the well pipe, the opening of the throttle valve is reduced until it is closed.

6. The control method of the slurry mixing system according to claim 5, characterized in that: The step of reducing the opening of the throttle valve until it is closed according to the real-time well pipe pressure in the well pipe comprises: In the process that the real-time well pipe pressure rises from the impact pressure to the first preset pressure, the opening of the throttle valve is reduced until it is closed.

7. The control method of the slurry mixing system according to claim 5, characterized in that: After the cementing operation is started, after obtaining the real-time outlet pressure of the oil pump and the real-time working pressure of the motor, the method further includes: Determining the adjustment trigger pressure according to the maximum working pressure; When the real-time outlet pressure is greater than the adjustment trigger pressure, the power of the oil pump is reduced until the real-time outlet pressure is less than or equal to the adjustment trigger pressure.

8. The control method of the slurry mixing system according to claim 5, characterized in that: After the cementing operation is started, after obtaining the real-time outlet pressure of the oil pump and the real-time working pressure of the motor, the method further includes: Obtaining a preset target flow rate of the slurry mixing system and a cumulative flow rate of the mud pump; Determining an adjustment trigger flow rate according to the preset target flow rate; When the accumulated flow is greater than the adjustment trigger flow, the displacement of the mud pump is reduced to be less than or equal to a preset displacement.

9. A storage medium, characterized in that: The storage medium stores a control program of a slurry mixing system, and when the control program of the slurry mixing system is executed by a processor, the control method of the slurry mixing system according to any one of claims 5 to 8 is implemented.

10. A controller, characterized in that: The controller includes a memory and a processor, and a control program of the slurry mixing system stored in the memory and operable on the processor, wherein the control program of the slurry mixing system is configured to implement the steps of the control method of the slurry mixing system according to any one of claims 5 to 8.

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