Cleaning method of well cementation slurry mixing equipment

Abstract

The invention relates to a cleaning method of well cementation and slurry mixing equipment, which comprises the following steps: blowing residual cement ash in a constant pressure tank to a high-energy mixer, mixing the residual cement ash with seawater, and discharging from a sewage outlet through a twenty-first valve and a thirty-ninth valve; cleaning a pipeline where the circulating densimeter is located and a pipeline where the pressurizing densimeter is located by using seawater in the metering tank; a circulating pipeline and a cement slurry manifold are cleaned, and after cleaning is completed, residual liquid in the slurry mixing pool and the balancing tank is discharged from a sewage draining exit through a twenty-first valve and a thirty-ninth valve by means of a circulating pump; the drilling water in the metering tank is used for cleaning valves at an outlet of the slurry mixing tank and an outlet of the balancing tank, and residual liquid in the metering tank is completely pumped into the balancing tank and the slurry mixing tank; the drilling water in the balancing tank and the slurry mixing pool is used for cleaning the large circulation pipeline, and the drilling water in the right metering tank is used for cleaning the small circulation pipeline. According to the cleaning method, the cleaning water consumption can be effectively reduced, and the cleaning efficiency is improved.

Description

Technical Field

[0001] This invention belongs to the field of oilfield cementing operation technology, specifically relating to a cleaning method for cementing mixing equipment. Background Technology

[0002] Cementing is the final step in oil drilling operations. During the process, cement slurry mixing equipment needs to mix cement slurry and pump it downhole. Cement slurry and dry cement residue adhere to the surface, components, manifolds, and operating system of the cement slurry mixing equipment. After the operation, the cement slurry is in a solidified or semi-solidified state, severely damaging the appearance and internal structure of the cement slurry mixing equipment. Because the operating system of the cement slurry mixing equipment is a relatively precise instrument, long-term cement contamination and corrosion will seriously affect the normal operation of the cement slurry mixing equipment, accelerate its aging, and shorten its service life. Therefore, cleaning is a crucial step after the cement slurry pumping operation.

[0003] Piping diagram of cementing mixing equipment as follows Figure 1 As shown, it includes a constant pressure tank, a equalization tank, a mixing tank, a metering tank consisting of a left metering tank and a right metering tank, a clean water pump, a standby clean water pump, a circulation pump, a filling pump, a left plunger pump, a right plunger pump, a circulating density meter, and a booster density meter, etc. The left engine drives the clean water pump, left plunger pump, and circulation pump; the right engine drives the injection pump, right plunger pump, and standby clean water pump. A gearbox is installed between the left engine and the left plunger pump, and a gearbox is installed between the right engine and the right plunger pump. Eleventh valve 11, twelfth valve 12, fifteenth valve 15, seventh valve 7, and thirty-fifth valve 35 are valves connecting the clean water pump to the lower ash head; eleventh valve 11, twelfth valve 12, fourteenth valve 14, ninth valve 9, and thirty-fifth valve 35 are valves connecting the standby clean water pump to the lower ash head; twenty-fourth valve 24, twenty-seventh valve 27, thirty-first valve 31, and thirty-fourth valve 34 are valves for the circulation pipeline; twenty-second valve 22, thirtieth valve 30, thirty-second valve 32, seventeenth valve 17, and eighteenth valve 18 are located on pipelines for cement grout injection. The pipelines containing valves 13 (23), 29 (29), 32 (32), 17 (17), and 18 (18) are backup cement grout injection pipelines; the pipelines containing valves 22 (22), 30 (30), 32 (32), 17 (17), 18 (18), 40 (40), 10 (10), 3rd plug valve P3, 4th plug valve P4, 5th plug valve P5, 6th plug valve P6, 7th plug valve P7, and 8th plug valve P8 are large circulation pipelines; the pipelines containing valves 11 (11), 16 (16), 19 (19), 20 (20), 40 (40), 10 (10), 3rd plug valve P3, 4th plug valve P4, 5th plug valve P5, 6th plug valve P6, 7th plug valve P7, and 8th plug valve P8 are small circulation pipelines.

[0004] The existing technology for cleaning cementing mixing equipment mainly involves using high-pressure water flow pumped by a centrifugal pump to repeatedly clean multiple components, including the pump head, plunger pump, density meter, mixer, flow meter, water supply pipeline, circulation pipeline, and discharge pipeline. However, since cementing mixing equipment involves many pumps / valves, the cleaning process has the disadvantage of complex start / stop operations. Furthermore, the current cleaning method is time-consuming, labor-intensive, has poor cleaning effect, and low cleaning efficiency. Summary of the Invention

[0005] In order to solve all or some of the above problems, the present invention aims to provide a cleaning method for cementing mixing equipment. The cleaning method for cementing mixing equipment of the present invention can effectively reduce the amount of cleaning water and improve the cleaning efficiency.

[0006] According to one aspect of the present invention, a cleaning method for a cementing mixing device is provided, comprising:

[0007] The remaining cement ash in the constant pressure tank is blown to the high-energy mixer, and the remaining cement ash is mixed with seawater and then discharged from the drain outlet through the twenty-first valve and the thirty-ninth valve.

[0008] The pipeline containing the circulating density meter and the pipeline containing the booster density meter are cleaned using seawater from the metering tank; the pipeline containing the circulating density meter is the pipeline connecting the circulating density meter flushing ball valve, the circulating density meter, and valves 31 to 34; the pipeline containing the booster density meter is the pipeline connecting the booster density meter flushing ball valve to the booster density meter.

[0009] The circulating pipeline, cement slurry manifold, and pipeline from valve 21 to the drain outlet are cleaned. After cleaning, the remaining liquid in the mixing tank and equalization tank is discharged from the drain outlet through valves 21 and 39 using a circulating pump. The cement slurry manifold includes the cement slurry injection pipeline, the pipeline containing valves 23, 29, and 33, the pipeline containing valve 26, the pipeline containing valves 16 and 11, and the pipeline containing valves 16 and 12.

[0010] The drilling water in the metering tank is used to clean the pipelines containing the fifteenth valve, the clean water pump, the sixth valve, and the eighth valve; the pipelines containing the fourteenth valve, the standby clean water pump, and the eighth valve are cleaned; the valves at the outlet of the mixing tank and the equalization tank are cleaned; and all the remaining liquid in the metering tank is pumped to the equalization tank and the mixing tank.

[0011] The drilling water in the equalization tank and mixing tank is used to clean the large circulation pipeline, and the drilling water in the right metering tank is used to clean the small circulation pipeline.

[0012] Furthermore, the step of purging the remaining cement ash in the constant pressure tank to a high-energy mixer, mixing the remaining cement ash with seawater, and then discharging it from the drain outlet through the twenty-first valve and the thirty-ninth valve further includes:

[0013] Open the clean water pump to the lower ash head valve, open the first valve, the second valve, the third valve, the nineteenth valve, the twentieth valve and the twenty-first valve, open the corresponding valves on the cement slurry injection pipeline, open the circulation pipeline valve, open the thirty-ninth valve, and close the remaining valves;

[0014] Seawater is added to the metering tank through the first valve, the second valve and the third valve. When the seawater in the metering tank reaches the first set volume, the clean water proportion valve is opened to increase the speed of the left engine. At the same time, the clean water pump is turned on to pump the seawater in the metering tank through the high-energy mixer to the mixing tank. The first set volume is 10BBL.

[0015] Open the ash proportioning valve and the thirty-sixth valve to purge the remaining cement ash in the constant pressure tank to the high-energy mixer;

[0016] Once the liquid level in the mixing tank reaches the first set level, the circulation pump is turned on to circulate the liquid between the mixing tank and the valves in the circulation pipeline; the first set level is 5 inches.

[0017] After the liquid level in the equalization tank reaches the second set liquid level, the injection pump is turned on to increase the speed of the right engine, so that the mixed cement slurry is discharged from the drain outlet through the cement slurry injection pipeline and the thirty-ninth valve. The second set liquid level is 27 inches.

[0018] When the weight of the remaining cement ash in the constant pressure tank reaches the set value, the thirty-sixth valve is closed after a first set time delay of 20 seconds. The set value is 100 lb.

[0019] Reduce the left engine speed to idle, stop the clean water pump and circulation pump, close the third valve, open the twenty-fifth and thirty-eighth valves, and use the injection pump to discharge the remaining liquid in the mixing tank and equalization tank through the cement slurry injection pipeline, the twenty-first valve and the thirty-ninth valve from the drain outlet. After the liquid level in the mixing tank and equalization tank reaches the minimum set value, reduce the right engine speed to idle and stop the injection pump; the minimum set value is 5 inches.

[0020] Furthermore, the step of opening the ash proportioning valve and the thirty-sixth valve to purge the remaining cement ash in the constant pressure tank to the high-energy mixer specifically involves: opening the ash proportioning valve to 50% of its opening, and after a second set time delay, opening the thirty-sixth valve to purge the remaining cement ash in the constant pressure tank to the high-energy mixer; when the remaining cement ash in the constant pressure tank reaches the set value, opening the ash proportioning valve to 100% of its opening, with the second set time being 3 seconds.

[0021] Furthermore, after the 36th valve is closed after a first set time delay following the ash weight of the remaining cement ash in the constant pressure tank reaches a set value, the method further includes: opening the blowing valve to blow the remaining cement ash in the pipeline to the high-energy mixer using an air source; and closing the blowing valve after there is no remaining cement ash in the pipeline.

[0022] Furthermore, the pipeline for cleaning the circulating density meter using seawater within the metering tank and the pipeline for the pressurized density meter further include:

[0023] Close valve 35, open valve 3 and valve 26, and keep the status of the remaining valves unchanged.

[0024] Seawater is added to the metering tank through the first valve, the second valve and the third valve. After the amount of seawater in the metering tank reaches the second set volume, the clean water pump is started to increase the speed of the left engine and open the flushing ball valve of the circulating density meter to clean the pipeline where the circulating density meter is located. The second set volume is 9BBL.

[0025] Open the flushing ball valve of the pressure density meter to allow the liquid to be discharged from the drain outlet through valves 17, 18, 19, 20, 21 and 39, in order to clean the pipeline where the pressure density meter is located;

[0026] After the cleaning water volume reaches the third set volume, stop the water pump and reduce the left engine to idle speed. The third set volume is 15BBL.

[0027] Furthermore, after the cleaning water volume reaches the third set volume, the water pump is stopped, and the left engine is reduced to idle speed, the method further includes:

[0028] Clean the ash head and diffusion tank; and discharge the residual cement slurry inside the mixing tank and equalization tank through the drain outlet via valves 26 and 39.

[0029] Furthermore, the cleaning of the circulation pipeline, cement slurry manifold, and pipeline from the twenty-first valve to the drain outlet, and the subsequent use of a circulation pump to discharge the remaining liquid in the mixing tank and equalization tank through the twenty-first valve and the thirty-ninth valve from the drain outlet after cleaning, further includes:

[0030] Open the clean water pump to the lower ash head valve, open the first valve, the second valve, the third valve, the nineteenth valve, the twentieth valve and the twenty-first valve, open the circulation pipeline valve, open the corresponding valves on the cement slurry injection pipeline, and close the remaining valves;

[0031] Seawater is added to the metering tank through the first valve, the second valve and the third valve. When the seawater in the metering tank reaches the fourth set volume, the clean water proportion valve is opened to increase the speed of the left engine. At the same time, the clean water pump is turned on to pump the seawater in the metering tank to the mixing tank. The fourth set volume is 10BBL.

[0032] When the liquid level in the mixing tank reaches the third set liquid level, the circulation pump is turned on to circulate the liquid between the mixing tank and the circulation pipeline valves to clean the circulation pipeline; the third set liquid level is 15 inches.

[0033] When the liquid level in the equalization tank reaches the fourth set liquid level, the injection pump is turned on, the thirty-ninth valve is opened, and the speed of the right engine is increased, so that the liquid is discharged from the drain outlet through the corresponding valves, the twenty-first valve and the thirty-ninth valve on the cement slurry injection pipeline to clean the cement slurry injection pipeline for the third set time; the fourth set liquid level is 27 inches and the third set time is 20 seconds.

[0034] Open valves 33, 23, 25, 28, 29, and 38; close valves 32, 22, 24, 27, and 30; keep the other valves in the same state; and clean the pipeline containing valves 23, 29, and 33 for a fourth set time, which is 30 seconds.

[0035] Stop the clean water pump, close the third valve, and open the tenth and thirteenth valves to drain the remaining liquid in the metering tank; stop the filling pump, reduce the right engine to idle speed, open the twenty-sixth valve, close the thirty-ninth valve, and use the circulation pump to clean the pipeline where the twenty-sixth valve is located for the fifth set time; the fifth set time is 10 seconds.

[0036] Open the sixteenth valve, close the twenty-sixth and twelfth valves, clean the pipelines containing the sixteenth and eleventh valves, and close the eleventh valve, open the twelfth valve, and clean the pipelines containing the sixteenth and twelfth valves for a sixth set time each, and then open the eleventh valve after cleaning; the sixth set time is 3 seconds.

[0037] After cleaning, open valve 39 and close valve 16. Use the circulation pump to discharge the remaining liquid in the mixing tank and equalization tank through valves 21 and 39 from the drain outlet to clean the pipeline from valve 21 to the drain outlet. After all the remaining liquid has been discharged, stop the circulation pump and reduce the left engine to idle speed.

[0038] Furthermore, the process of opening valves 33, 23, 25, 28, 29, and 38, closing valves 32, 22, 24, 27, and 30, with the remaining valves remaining unchanged, and cleaning the pipelines containing valves 23, 29, and 33 for the fourth set time is as follows:

[0039] Open valves 33, 23, 25, 28, 29, and 38; close valves 32, 22, 24, 27, and 30; leave the remaining valves unchanged.

[0040] Close valves 17 and 19, and use a circulation pump to clean the pipelines containing valves 23, 29, and 33, as well as valves 18 and 20 for 15 seconds; open valves 17 and 19, close valves 18 and 20, and use a circulation pump to clean the pipelines containing valves 23, 29, and 33, as well as valves 17 and 19 for 15 seconds.

[0041] During the closing of valves 17 and 19, as well as valves 18 and 20, a grouting pump is used to allow the liquid in the mixing tank to flow back into the mixing tank through valve 25, the grouting pump, and valve 28; and valves 18 and 20 are opened after cleaning.

[0042] Furthermore, after the cleaning is completed, the thirty-ninth valve is opened and the sixteenth valve is closed. The remaining liquid in the mixing tank and equalization tank is discharged from the drain outlet through the twenty-first and thirty-ninth valves using a circulation pump to clean the pipeline from the twenty-first valve to the drain outlet. After all the remaining liquid has been discharged, the circulation pump is stopped, and the left engine is reduced to idle speed. The method further includes:

[0043] After the remaining liquid in the metering tank has been completely drained, close valves 10 and 13.

[0044] Furthermore, after cleaning the circulation pipeline, cement slurry manifold, and the pipeline from valve 21 to the drain outlet, and after using a circulation pump to discharge the remaining liquid in the mixing tank and equalization tank through valves 21 and 39 from the drain outlet, the method further includes:

[0045] Open the first and fourth valves to add drilling water to the right metering tank. After the right metering tank is full, close the first valve. Open the second valve to add drilling water to the left metering tank. After the left metering tank is full, close the second valve.

[0046] Furthermore, the step of using drilling water from the metering tank to clean the pipelines containing the fifteenth valve, the clean water pump, the sixth valve, and the eighth valve; cleaning the pipelines containing the fourteenth valve, the standby clean water pump, and the eighth valve; cleaning the valves at the outlet of the mixing tank and the equalization tank; and pumping all remaining liquid in the metering tank to the equalization tank and the mixing tank further includes:

[0047] Open valves 11, 12, 15, 6, 8, 14, 17, 18, 19, 20, 21, and 39; close the remaining valves.

[0048] After the drilling water volume in the metering tank reaches the fifth set volume, start the clean water pump and the standby clean water pump, increase the speed of the left engine and the right engine, and clean the pipelines where the fifteenth valve, the sixth valve, and the eighth valve are located, as well as the pipelines where the fourteenth valve, the standby clean water pump, and the eighth valve are located for a total of a seventh set time; and after cleaning for the seventh set time, stop the clean water pump and the standby clean water pump. The seventh set time is 5 seconds, and the fifth set volume is 10 BBL.

[0049] Fill the metering tank with drilling water, and then close the fourth valve 4 after filling the metering tank with drilling water;

[0050] Open valves 26 and 22, close valve 39, leaving the other valves unchanged. Start the clean water pump and the standby clean water pump to allow drilling water in the metering tank to enter the equalization tank through valves 26 and 22 to flush valve 22. Close valve 22, open valve 25, and allow drilling water in the metering tank to enter the mixing tank through valves 26 and 25 to flush valve 25. Close valves 25 and 26, open valves 23 and 32, and allow drilling water in the metering tank to enter the equalization tank through valve 32 and the circulation pump to flush valve 23. Close valve 23, open valve 24, and allow drilling water in the metering tank to enter the mixing tank through valve 32 and the circulation pump to flush valve 24. Each of valves 22, 23, 24, and 25 is flushed for an eighth set time; the eighth set time is 5 seconds.

[0051] Open valves 26, 22, 23, and 25, and use the clean water pump and the standby clean water pump to pump all the remaining drilling water in the metering tank to the equalization tank and the mixing tank. After pumping all the remaining drilling water in the metering tank to the equalization tank and the mixing tank, stop the clean water pump and the standby clean water pump, and set the left and right engines to idle speed.

[0052] Furthermore, after opening valves 26, 22, 23, and 25 to pump all remaining liquid in the metering tank to the equalization tank and mixing tank, stopping the clean water pump and the standby clean water pump, and setting the left and right engines to idle speed, the method further includes:

[0053] Open the circulation pipeline valves and the corresponding valves of the cement slurry injection pipeline. Open the clean water proportioning valve, valve number nine, valve number eight, valve number thirty-three, valve number twenty-eight, valve number twenty-nine, valve number nineteen, valve number twentieth, valve number twenty-first, valve number twenty-six, valve number twenty-third, valve number twenty-fifth, valve number thirty-eight, and valve number thirty-fifth. Close the remaining valves. Turn on the circulation pump and injection pump, and increase the speed of the left and right engines. Use the drilling water in the equalization tank and mixing pool to clean the pipelines for the ninth set time. The pipelines to be cleaned include the circulation pipeline, the cement slurry injection pipeline, the standby cement slurry injection pipeline, and the pipeline where valve number twenty-six is ​​located. After cleaning, stop the circulation pump and injection pump, and adjust the left and right engines to idle speed. The ninth set time is 30 seconds.

[0054] Furthermore, the step of using drilling water from the equalization tank and mixing tank to clean the large circulation pipeline, and using drilling water from the right metering tank to clean the small circulation pipeline, further includes:

[0055] Open the corresponding valves in the main circulation pipeline: open valves 23, 24, 27, 31, 25, and 38, and close the remaining valves. Increase the speed of the left engine and start the circulation pump to circulate the liquid between the mixing tank and the circulation pipeline valves. After starting the circulation pump for 20 seconds, open valve 34. When the liquid level in the mixing tank is below 12 inches, stop the circulation pump and reduce the left engine speed to idle.

[0056] Start the injection pump and increase the speed of the left and right engines to drain the liquid in the mixing tank and equalization tank through the large circulation pipeline to clean the large circulation pipeline. When 10% of the liquid remains in the mixing tank and equalization tank, reduce the speed of the left and right engines to idle and stop the injection pump.

[0057] Add the sixth set volume of drilling water to the right metering tank, open the valve where the small circulation pipeline is located, close the other valves, increase the speed of the left and right engines to use the drilling water in the right metering tank to clean the small circulation pipeline until the liquid in the right metering tank is 10% remaining, then reduce the left and right engines to idle speed. The sixth set volume is 9BBL.

[0058] Furthermore, after using drilling water from the equalization tank and mixing tank to clean the large circulation pipeline and using drilling water from the right metering tank to clean the small circulation pipeline, the method further includes: draining the remaining liquid from the equalization tank, mixing tank and right metering tank.

[0059] The process of draining the remaining liquid from the equalization tank, mixing tank, and right metering tank involves: closing the first valve, second valve, third valve, fourth valve, fifth valve, and thirty-sixth valve; keeping the first and second stopcock valves closed; and opening the remaining valves to drain the remaining liquid from the mixing tank and equalization tank, as well as the remaining liquid from the right metering tank.

[0060] Furthermore, starting the injection pump and increasing the speed of the left and right engines allows the liquid in the mixing tank and equalization tank to be discharged through the large circulation pipeline to clean the large circulation pipeline. This process continues until 10% of the liquid remains in the mixing tank and equalization tank. Then, the left and right engines are reduced to idle speed, and the injection pump is stopped. Specifically:

[0061] Start the injection pump, increase the speed of the left and right engines, and discharge the liquid in the mixing tank and equalization tank through the large circulation pipeline for the tenth set time, which is 10 seconds.

[0062] Close the sixth stopcock valve and clean again for the eleventh set time, which is 15 seconds.

[0063] Open the sixth stopcock valve, close the seventh stopcock valve, and perform the third cleaning at the eleventh set time;

[0064] Open the seventh stopcock valve to continue cleaning until 10% of the liquid remains in the mixing tank and equalization tank. Then, reduce the left and right engines to idle speed and stop the injection pump.

[0065] As can be seen from the above technical solution, the cleaning method for cementing mixing equipment provided by the present invention has the following beneficial effects:

[0066] The cleaning method of the present invention greatly reduces the labor intensity of operators; the cleaning method of the present invention can effectively reduce the amount of cleaning water and improve cleaning efficiency; the cleaning method of the present invention adopts a combination of manual / automatic and computer control and manual operation, which can target and repeat the cleaning of key parts, and can effectively solve the problem of incomplete cleaning of components such as densitometers. Attached Figure Description

[0067] Figure 1 This is a schematic diagram of a cleaning method for a cementing slurry mixing device according to an embodiment of the present invention;

[0068] Figure 2 This is a design logic diagram of the cleaning method according to an embodiment of the present invention;

[0069] Figure 3 This is a flowchart of a cleaning method for a cementing slurry mixing device according to an embodiment of the present invention;

[0070] Figure 4 A schematic diagram of an automatic cleaning control system;

[0071] Figure 5 This is a detailed flowchart of step S1 in an embodiment of the present invention;

[0072] Figure 6 This is a detailed flowchart of step S2 in an embodiment of the present invention;

[0073] Figure 7 This is a flowchart illustrating step S3 in an embodiment of the present invention.

[0074] Figure 8 This is a detailed flowchart of step S4 in an embodiment of the present invention;

[0075] Figure 9 This is a flowchart of step S5 in an embodiment of the present invention. Detailed Implementation

[0076] To better understand the purpose, structure, and function of this invention, the following detailed description, in conjunction with the accompanying drawings, provides a method for cleaning a cementing slurry mixing device according to this invention.

[0077] A cleaning method for cementing slurry mixing equipment according to an embodiment of the present invention is applied to cleaning cementing slurry mixing equipment, such as... Figure 1 As shown, before the actual cleaning, the pipeline of the cementing mixing equipment needs to be switched to the cleaning process, and the first plug valve P1 and the second plug valve P2 leading to the drilling platform need to be closed.

[0078] Among them, such as Figures 2-3 As shown, the cleaning method for cementing mixing equipment includes the following steps:

[0079] Step S1: Purge the remaining cement ash in the constant pressure tank to the high-energy mixer, mix the remaining cement ash with seawater, and then discharge it from the drain outlet through valve 21 and valve 39.

[0080] Step S2: Use seawater from the metering tank to clean the pipeline containing the circulating density meter and the pipeline containing the booster density meter; the pipeline containing the circulating density meter is the pipeline from the circulating density meter flushing ball valve, the circulating density meter, and valves 31 to 34; the pipeline containing the booster density meter is the pipeline from the booster density meter flushing ball valve to the booster density meter.

[0081] Step S3: Clean the circulation pipeline, cement slurry manifold, and the pipeline from valve 21 to the drain outlet. After cleaning, use the circulation pump to discharge the remaining liquid in the mixing tank and equalization tank through valves 21 and 39 from the drain outlet. The cement slurry manifold includes the cement slurry injection pipeline, the pipeline containing valves 23, 29, and 33, the pipeline containing valve 26, the pipeline containing valves 16 and 11, and the pipeline containing valves 16 and 12.

[0082] Step S4: Use the drilling water in the metering tank to clean the pipelines containing valve 15, the clean water pump, valve 6, and valve 8; clean the pipelines containing valve 14, the standby clean water pump, and valve 8; clean the valves at the outlet of the mixing tank and the equalization tank; and pump all remaining liquid in the metering tank to the equalization tank and the mixing tank; and

[0083] Step S5: Use drilling water from the equalization tank and mixing tank to clean the large circulation pipeline, and use drilling water from the right metering tank to clean the small circulation pipeline.

[0084] In practice, cleaning of cementing equipment can be achieved through a combination of automatic and manual cleaning. In automatic mode, the controller automatically runs from the first stage to the last stage according to the set parameters for each stage. In manual mode, the operator can select any stage to run multiple times as needed, focusing on cleaning certain components.

[0085] The automatic cleaning process is achieved through a PLC controller and an HMI control panel. Specifically, for example... Figure 4 As shown, the PLC controller collects the liquid level signals of the left and right metering tanks, the liquid level signals of the mixing tank and the equalization tank, the weight signal of the ash in the constant pressure tank, the opening signals of the ash proportioning valve B2 and the clean water proportioning valve B1, and the operating parameters and status information of the left engine, right engine, left transmission box, right transmission box, clean water pump, standby clean water pump, circulation pump, injection pump, metering tank agitator, mixing tank agitator, equalization tank agitator, various butterfly valves, and 8 plug valves. The cleaning parameters are set through the HMI operation screen. The PLC controller uses the clock method and parameter limitation method to realize the automatic switching of the manifold, the start / stop of the centrifugal pump and agitator, and the control of the engine speed and transmission box gear.

[0086] For automatic cleaning, set the cleaning parameters on the HMI and select the control mode according to the operation requirements. In automatic mode, press the "Start Cleaning" button on the HMI and the controller will automatically run from the first stage to the last stage according to the set parameters of each stage. In manual mode, the operator can press the "Start Step S1" to "Start Step S5" buttons as needed to select any one of the five steps to focus on cleaning certain parts.

[0087] For cleaning methods that combine automatic and manual cleaning, automatic cleaning runs automatically according to the set process, which can greatly reduce the labor intensity of operators; automatic cleaning uses the clock method and parameter limit method for process control, which can effectively reduce the amount of cleaning water and improve cleaning efficiency; during cleaning, key parts can be cleaned repeatedly in a targeted manner, which can effectively solve the problem of incomplete cleaning of components such as densitometers.

[0088] Regarding step S1, this embodiment adjusts the engine speed by opening / closing valves and starting / stopping the clean water pump, circulation pump, injection pump, and corresponding agitator according to the liquid levels in the metering tank and mixing tank, as well as the running time. This is done to blow the remaining cement ash in the constant pressure tank to the mixing tank for mixing and then discharge it through the pressurized pipeline to the drain outlet. In addition, manual operation is used to blow the ash conveying pipeline and the ash discharge valve. Finally, the cleaning of cement ash is stopped by manually inputting a command.

[0089] Specifically, such as Figure 5 As shown, step S1, which involves purging the remaining cement ash from the constant pressure tank to a high-energy mixer, mixing the remaining cement ash with seawater, and then discharging it from the drain outlet through valves 21 and 39, further includes:

[0090] Step S11: Open the clean water pump to the lower ash head valve, open the first valve, the second valve, the third valve, the nineteenth valve, the twentieth valve and the twenty-first valve, open the corresponding valves on the cement slurry injection pipeline, open the circulation pipeline valve, open the thirty-ninth valve 39, and close the remaining valves.

[0091] In this embodiment, the opening of each valve can be achieved through a PLC controller. Before step S11, the PLC controller also receives cleaning setting parameters set on the HMI, collects the ash weight of the constant pressure tank, collects the liquid levels of the mixing tank and the equalization tank, collects the liquid levels of the left and right metering tanks, and converts them into volume.

[0092] Among them, valves 11, 12, 15, 7, and 35 are valves from the clean water pump to the lower ash head; valves 22, 30, 32, 17, and 18 are corresponding valves on the cement grouting pipeline.

[0093] Step S12: Add seawater into the metering tank through the first valve, the second valve and the third valve. After the seawater in the metering tank reaches the first set volume, open the clean water proportion valve B1, increase the speed of the left engine, and at the same time start the clean water pump to pump the seawater in the metering tank through the high-energy mixer to the mixing tank. The first set volume is 10BBL.

[0094] Step S12 involves opening the first, second, and third valves to pump seawater into the metering tank. In this embodiment, a first set volume (i.e., 10BBL, where BBL refers to the tank) of seawater is added to the metering tank consisting of the left and right metering tanks. This first set volume can be adjusted based on the ash weight of the constant pressure tank, the liquid levels collected in the mixing tank and equalization tank, and the liquid levels collected in the left and right metering tanks. After sufficient seawater is added to the metering tank, the third valve 3 is opened to its maximum position; simultaneously, the clean water proportioning valve B1 is opened, the clean water pump is started, and the speed of the left engine is increased to 1600 rpm, pumping the seawater in the metering tank through the high-energy mixer to the mixing tank. The seawater in the metering tank is then pumped through the clean water pump to the lower ash head valve, the clean water proportioning valve B1, and the high-energy mixer before entering the mixing tank. The clean water pump to the lower ash head valve refers to the eleventh valve 11, the twelfth valve 12, the fifteenth valve 15, the seventh valve 7, and the thirty-fifth valve 35.

[0095] It should also be noted that of the three valves—the third valve 3, the fourth valve 4, and the fifth valve 5—one is used to introduce seawater into the metering tank, another is used to introduce drilling water, and the third is used to introduce mud. The specific method used depends on the site conditions. This embodiment uses the example of the third valve 3 introducing seawater and the fourth valve 4 introducing drilling water into the metering tank.

[0096] Step S13: Open the ash proportioning valve B2 and the thirty-sixth valve 36 to purge the remaining cement ash in the constant pressure tank to the high-energy mixer.

[0097] Specifically, step S13, opening the ash proportioning valve B2 and the thirty-sixth valve 36 to purge the remaining cement ash in the constant pressure tank to the high-energy mixer, involves: opening the ash proportioning valve B2 to 50% of its opening, and after a second set delay, opening the thirty-sixth valve 36 to purge the remaining cement ash in the constant pressure tank to the high-energy mixer. When the remaining cement ash in the constant pressure tank reaches a set value, the ash proportioning valve B2 is opened to 100% of its opening, with the second set delay being 3 seconds. In this embodiment, after the remaining cement ash in the constant pressure tank is purged to the high-energy mixer, the remaining cement ash is mixed with seawater, and the mixture flows into the mixing tank together.

[0098] Step S14: When the liquid level in the mixing tank reaches the first set liquid level, turn on the circulation pump to circulate the liquid between the mixing tank and the circulation pipeline valve; the first set liquid level is 5 inches.

[0099] The purpose of starting the circulation pump in step S14 is to circulate the liquid between the mixing tank and the circulation pipeline valves. The circulation pipeline valves refer to valves 24, 27, 31, and 34. The liquid flows out of the mixing tank through valve 24, and then splits into two paths after passing through the circulation pump and valve 27. One path flows into the mixing tank through valve 31 and the circulation density meter, while the other path flows into the mixing tank through valve 34 and the high-energy mixer.

[0100] Step S15: After the liquid level in the equalization tank reaches the second set liquid level, turn on the injection pump and increase the speed of the right engine so that the mixed cement slurry is discharged from the drain port through the cement slurry injection pipeline and the thirty-ninth valve 39. The second set liquid level is 27 inches.

[0101] The mixing tank has an overflow valve at the top, which overflows the liquid in the mixing tank to the equalization tank. Therefore, when the seawater level in the mixing tank is above the overflow valve, the seawater in the mixing tank will overflow to the equalization tank. Step S15 is used to discharge the seawater overflowing into the equalization tank from the drain outlet after the liquid level in the equalization tank reaches the second set liquid level. Specifically, after the liquid level in the equalization tank reaches the second set liquid level, the injection pump is turned on, and the speed of the right engine is increased to 1600 rpm, so that the cement slurry is discharged from the drain outlet through the injection pump and the cement slurry injection pipeline.

[0102] The cement grout injection pipeline refers to the pipeline containing valves 22, 30, 32, 17, and 18. The specific flow path of the liquid is as follows: it exits the equalization tank through valve 22, passes through the injection pump, valves 30 and 32, and the pressure-boosting density meter, then splits into two paths. One path passes through valves 18 and 20, and the other through valves 17 and 19. The two paths then merge and are discharged from the drain outlet through valves 21 and 39.

[0103] Step S16: When the weight of the remaining cement ash in the constant pressure tank reaches the set value, the thirty-sixth valve 36 is closed after a first set time delay. The first set time is 20 seconds, and the set value is 100 lb.

[0104] Regarding step S16, after closing the thirty-sixth valve, the automatic cleaning system will display a "Stop purging ash conveying pipeline" prompt. You can confirm "Stop purging ash conveying pipeline"; alternatively, you can first perform manual purging and then confirm "Stop purging ash conveying pipeline". After confirming "Stop purging ash conveying pipeline", proceed to step S17.

[0105] The manual blowing operation refers to the following: after the weight of the remaining cement ash in the constant pressure tank reaches the set value and the thirty-sixth valve 36 is closed after a first set time delay, the method further includes: opening the blowing valve B3 and using an air source to blow the remaining cement ash in the pipeline to the high-energy mixer; and closing the blowing valve B3 after there is no remaining cement ash in the pipeline.

[0106] Step S17: Reduce the speed of the left engine to idle, stop the clean water pump and circulation pump, close the third valve 3, open the twenty-fifth valve 25 and the thirty-eighth valve 38, and use the injection pump to discharge the remaining liquid in the mixing tank and equalization tank through the cement slurry injection pipeline, the twenty-first valve and the thirty-ninth valve 39 from the drain outlet. After the liquid level of the remaining liquid in the mixing tank and equalization tank reaches the minimum set value, reduce the speed of the right engine to idle and stop the injection pump; the minimum set value is 5 inches.

[0107] In this step, after closing the third valve 3, seawater no longer enters the metering tank. After opening the twenty-fifth valve 25, the cement slurry in the mixing tank is discharged from the drain outlet through the cement slurry injection pipeline, the twenty-first valve, and the thirty-ninth valve 39. The flow of cement slurry in the equalization tank will not be described further. When the remaining liquid level in the mixing tank and the equalization tank reaches the minimum set value, the right engine is reduced to idle speed, the injection pump is stopped, and the cleaning process proceeds to step S2.

[0108] Specifically, regarding the cleaning in step S1, the following explanation is needed: In step S1, the agitator in the mixing tank is controlled at three opening degrees: 0%, 50%, and 70%, based on the liquid level in the mixing tank; similarly, the agitator in the equalization tank is controlled at three opening degrees: 0%, 50%, and 70%, based on the liquid level in the equalization tank; and the lower the liquid level, the smaller the agitator opening degree. Specifically, when the liquid in the mixing tank submerges the top layer of agitator blades, the agitator opening degree is 70%; when the liquid is below the top layer of agitator blades, the agitator opening degree is 50%; and when the liquid is below the bottom layer of agitator blades, the agitator opening degree is 0%. The equalization tank operates similarly.

[0109] Furthermore, to ensure sufficient water supply in the metering tank, the following measures are also required: when the liquid level in the metering tank is below 20%, the opening of the clean water proportional valve should be appropriately reduced; when the liquid level in the metering tank reaches 40%, the clean water proportional valve should be gradually adjusted to its maximum; and when the liquid level in the metering tank reaches 90%, the third valve 3 should be closed in advance.

[0110] Finally, to prevent the equalization tank from evacuating or overflowing, the following measures should be taken: When the liquid level in the equalization tank is below 10%, open valve 28 and close valve 32 to allow the liquid discharged from the injection pump to return to the mixing tank through valve 28; when the liquid level in the equalization tank is above 70%, open valve 32 and close valve 28 to restore normal operation; when the liquid level in the equalization tank reaches 80%, appropriately reduce the opening of the clear water proportioning valve.

[0111] Regarding step S2, this embodiment adjusts the engine speed by opening / closing valves and starting / stopping the clean water pump and corresponding agitator according to the liquid levels in the metering tank and mixing tank, as well as the running time, and cleans the circulating density meter and booster density meter. It also combines manual operation to clean the residual cement slurry in the ash head, diffusion tank, mixing tank and equalization tank, and stops manual cleaning by manually inputting commands.

[0112] Specifically, such as Figure 6 As shown, step S2, which uses seawater from the metering tank to clean the pipeline containing the circulating density meter and the pipeline containing the pressurized density meter, further includes:

[0113] Step S21: Close the thirty-fifth valve 35, open the third valve 3 and the twenty-sixth valve 26, and keep the status of the remaining valves unchanged.

[0114] In this embodiment, the opening of each valve can be achieved through a PLC controller. Before step S21, the PLC controller receives cleaning setting parameters set on the HMI, collects the liquid levels of the left and right metering tanks, and converts them into volume.

[0115] Step S22: Add seawater into the metering tank through the first valve, the second valve and the third valve. After the amount of seawater in the metering tank reaches the second set volume, start the clean water pump, increase the speed of the left engine, and open the flushing ball valve of the circulating density meter to clean the pipeline where the circulating density meter is located. The second set volume is 9BBL.

[0116] Regarding step S22, after opening the circulating density meter flushing ball valve, the seawater in the metering tank is divided into two streams after passing through the clean water pump, valve 7 (seventh valve), and the circulating density meter flushing ball valve. One stream flows directly into the mixing tank, while the other stream flows into the mixing tank through the circulating density meter, valve 31 (thirty-first valve), valve 34 (thirty-fourth valve), and the high-energy mixer. The liquid in the mixing tank is discharged from the drain outlet through valve 25 (twenty-fifth valve), valve 26 (twenty-sixth valve), and valve 39 (thirty-ninth valve). Specifically, increasing the left engine speed means increasing the left engine speed to 1600 rpm.

[0117] The liquid flow cleaned the cement slurry remaining on the corresponding pipelines after step S1, thus achieving the purpose of cleaning the following parts: cleaning the circulating density meter flushing ball valve, circulating density meter, valve 31, valve 34 and high-energy mixer, cleaning the slurry tank, valve 25, valve 26 and valve 39.

[0118] Step S23: Open the flushing ball valve of the pressure density meter to allow liquid to be discharged from the drain port through valves 17, 18, 19, 20, 21 and 39 to clean the pipeline where the pressure density meter is located.

[0119] In step S23, after opening the pressure density meter flushing ball valve, the seawater in the metering tank flows through the clean water pump and the seventh valve 7, then through the pressure density meter flushing ball valve, and then through the seventeenth, eighteenth, nineteenth, twentieth, twenty-first, and thirty-ninth valves 21 and 39, and is discharged from the drain outlet. The liquid flow achieves the purpose of cleaning the following parts: cleaning the pressure density meter flushing ball valve, and cleaning the seventeenth, eighteenth, nineteenth, twentieth, twenty-first, and thirty-ninth valves 39.

[0120] Step S24: After the cleaning water volume reaches the third set volume, stop the water pump and reduce the left engine to idle speed. The third set volume is 15BBL.

[0121] After step S24, the automatic cleaning system will display a "Yes / No" prompt to "End Manual Cleaning". If manual cleaning is not required, the manual cleaning operation can be ended. If manual cleaning is required, after the cleaning water volume reaches the third set volume in step S24, the clean water pump is stopped, and the left engine is reduced to idle speed. The cleaning method also includes: cleaning the lower ash head and diffusion tank; and discharging the residual cement slurry inside the mixing tank and equalization tank through the drain outlet via valves 26 and 39. Cleaning the lower ash head and diffusion tank constitutes the manual cleaning operation; after completion, the manual cleaning operation can be ended. After confirming the "End Manual Cleaning" operation, the system proceeds to step S3 for cleaning.

[0122] Regarding step S3, in this embodiment, based on the liquid levels in the metering tank and mixing tank, as well as the running time, the valves are opened / closed and the clean water pump, standby clean water pump, circulation pump, injection pump, and corresponding agitator are started / stopped. The engine speed is adjusted to clean each cement slurry manifold, and the remaining liquid in the mixing tank and equalization tank is discharged through the drain outlet using the circulation pump.

[0123] Specifically, such as Figure 7As shown, step S3, cleaning the circulation pipeline, cement slurry manifold, and the pipeline from valve 21 to the drain outlet, and after cleaning, using a circulation pump to discharge the remaining liquid in the mixing tank and equalization tank through valves 21 and 39 from the drain outlet, further includes:

[0124] Step S31: Open the clean water pump to the lower ash head valve, open the first valve, the second valve, the third valve, the nineteenth valve, the twentieth valve and the twenty-first valve, open the circulation pipeline valve, open the corresponding valve on the cement slurry injection pipeline, and close the remaining valves.

[0125] In this embodiment, the opening of each valve can be achieved through a PLC controller. Before step S31, the PLC controller receives cleaning setting parameters set on the HMI, collects the liquid levels in the mixing tank and equalization tank, collects the liquid level in the metering tank, and converts the liquid levels into volume. Among them, the pipelines containing the 22nd valve 22, the 30th valve 30, the 32nd valve 32, the 17th valve 17, and the 18th valve 18 are cement grout injection pipelines.

[0126] Step S32: Add seawater into the metering tank through the first valve, the second valve and the third valve. After the seawater in the metering tank reaches the fourth set volume, open the clean water proportion valve B1, increase the speed of the left engine, and at the same time start the clean water pump to pump the seawater in the metering tank to the mixing tank. The fourth set volume is 10BBL.

[0127] Step S33: When the liquid level in the mixing tank reaches the third set liquid level, turn on the circulation pump to circulate the liquid between the mixing tank and the circulation pipeline valve to clean the circulation pipeline; the third set liquid level is 15 inches.

[0128] Step S34: When the liquid level in the equalization tank reaches the fourth set liquid level, start the injection pump, open the thirty-ninth valve 39, increase the speed of the right engine, and allow the liquid to be discharged from the drain port through the corresponding valves, the twenty-first valve and the thirty-ninth valve 39 on the cement slurry injection pipeline to clean the cement slurry injection pipeline for the third set time; the fourth set liquid level is 27 inches and the third set time is 20 seconds.

[0129] For step S34, increasing the speed of the right engine means increasing the speed of the right engine to 1600 rpm. After starting the injection pump, the flow path of the liquid is as follows: it is discharged from the drain port through the corresponding valves, valve 21, and valve 39 on the cement slurry injection pipeline.

[0130] Step S35: Open valves 33, 23, 25, 28, 29, and 38; close valves 32, 22, 24, 27, and 30; leave the other valves in their original states; and clean the pipeline containing valves 23, 29, and 33 for a fourth set time, which is 30 seconds.

[0131] In step S35, opening valves 33, 23, 25, 28, 29, and 38, and closing valves 32, 22, 24, 27, and 30, while keeping the other valves in their original states, further includes the following steps: The fourth set time for cleaning the pipeline containing valves 23, 29, and 33 includes...

[0132] Step S351: Open valves 33, 23, 25, 28, 29 and 38, and close valves 32, 22, 24, 27 and 30. The status of the remaining valves remains unchanged.

[0133] Step S352: Close valves 17 and 19, and use a circulation pump to clean the pipelines containing valves 23, 29, and 33, as well as valves 18 and 20 for 15 seconds; open valves 17 and 19, close valves 18 and 20, and use a circulation pump to clean the pipelines containing valves 23, 29, and 33, as well as valves 17 and 19 for 15 seconds.

[0134] Step S353: During the process of closing the seventeenth valve 17 and the nineteenth valve 19, and during the process of closing the eighteenth valve 18 and the twentieth valve 20, the liquid in the mixing tank is used to flow back into the mixing tank through the twenty-fifth valve, the injection pump and the twenty-eighth valve; and after cleaning, the eighteenth valve 18 and the twentieth valve 20 are opened.

[0135] In this embodiment, valves 17 and 19 are flushed for 15 seconds, and valves 18 and 20 are flushed for 15 seconds. This time can be modified on the HMI. The valves are opened and closed according to the principle of opening first and then closing.

[0136] Step S36: Stop the clean water pump, close the third valve 3, and open the tenth valve 10 and the thirteenth valve 13 to drain the remaining liquid in the metering tank; stop the filling pump, reduce the right engine to idle speed, open the twenty-sixth valve 26, close the thirty-ninth valve 39, and use the circulation pump to clean the pipeline where the twenty-sixth valve 26 is located for the fifth set time; the fifth set time is 10s.

[0137] Among them, the tenth valve 10 and the thirteenth valve 13 are the drain valves of the corresponding metering tanks. In this embodiment, the purpose of opening the tenth valve 10 and the thirteenth valve 13 is to drain the remaining liquid in the metering tank. In step S36, during the fifth set time process of cleaning the pipeline where the twenty-sixth valve 26 is located using the circulating pump, the specific flow path of the liquid is as follows: sequentially through the twenty-third valve 23, the circulating pump, the twenty-ninth valve 29, the thirty-third valve 33, the twenty-first valve 21 and the twenty-sixth valve 26, and finally returning to the mixing tank through the twenty-fifth valve 25. Step S36 cleans the pipeline where the twenty-sixth valve 26 is located.

[0138] Step S37: Open the sixteenth valve 16, close the twenty-sixth valve 26 and the twelfth valve 12, clean the pipeline where the sixteenth valve 16 and the eleventh valve 11 are located, close the eleventh valve 11, open the twelfth valve 12, clean the pipeline where the sixteenth valve 16 and the twelfth valve 12 are located for a sixth set time, and open the eleventh valve 11 after cleaning; the sixth set time is 3s.

[0139] Regarding step S37: Taking opening valve 16 and closing valves 26 and 12 as an example, the liquid flow path is as follows: sequentially passing through valve 23, the circulation pump, valve 29, valve 33, and valve 16, finally flowing into the right metering tank through valve 11 and discharging through valve 13. When valve 11 is closed and valve 12 is opened, the liquid flows into the left metering tank through valve 12 and discharging through valve 10. Step S37 achieves the purpose of cleaning the corresponding pipelines and valves.

[0140] Step S38: After cleaning, open valve 39 and close valve 16. Use the circulation pump to discharge the remaining liquid in the mixing tank and equalization tank through valves 21 and 39 from the drain outlet to clean the pipeline from valve 21 to the drain outlet. After all the remaining liquid has been discharged, stop the circulation pump and reduce the left engine to idle speed.

[0141] Regarding step S38: Since valve 38 was opened in step S35, the liquid in the mixing tank can flow into the equalization tank through valve 38. When the remaining liquid in the mixing tank and equalization tank is discharged by the circulation pump, the liquid flow path is as follows: the liquid in the mixing tank flows into the equalization tank through valve 38, and the liquid in the equalization tank flows through valve 23, circulation pump, valve 29, valve 33, and valve 21 in sequence, and finally is discharged from the drain outlet through valve 39.

[0142] After cleaning is completed in step S38, open valve 39 and close valve 16. Use a circulation pump to discharge the remaining liquid in the mixing tank and equalization tank through valves 21 and 39 from the drain outlet to clean the pipeline from valve 21 to the drain outlet. After all the remaining liquid is discharged, stop the circulation pump and reduce the left engine to idle speed. The method also includes closing valve 10 and valve 13 after the remaining liquid in the metering tank is completely discharged.

[0143] Since the liquid in the metering tank was completely drained in step S3, the cement slurry manifold was cleaned with seawater from the metering tank in step S3. After the cleaning was completed, the remaining liquid in the mixing tank and equalization tank was discharged from the drain outlet through valve 21 and valve 39 using a circulation pump. The method also includes: opening valve 1 and valve 4 to add drilling water to the right metering tank, and closing valve 1 after filling the right metering tank; opening valve 2 to add drilling water to the left metering tank, and closing valve 2 after filling the left metering tank.

[0144] The process then proceeds to step S4, which involves cleaning. In step S4, this embodiment adjusts the engine speed by opening / closing valves and starting / stopping the clean water pump, standby clean water pump, circulation pump, injection pump, and corresponding agitator, based on the levels in the metering tank and mixing tank, as well as the running time. This cycle cleans the pump head and cement slurry manifold repeatedly. After completion, the process automatically moves to the next stage.

[0145] Specifically, such as Figure 8 As shown, step S4 involves using drilling water from the metering tank to clean the pipelines containing the fifteenth valve 15, the clean water pump, the sixth valve 6, and the eighth valve 8; cleaning the pipelines containing the fourteenth valve, the standby clean water pump, and the eighth valve; cleaning the valves at the outlet of the mixing tank and the equalization tank; and pumping all remaining liquid in the metering tank to the equalization tank and the mixing tank. This step further includes:

[0146] S41: Open valves 11, 12, 15, 6, 8, 14, 17, 18, 19, 20, 21 and 39, and close the remaining valves.

[0147] In this embodiment, the opening of each valve can be achieved through a PLC controller. Before step S41, the PLC controller receives cleaning setting parameters set on the HMI, collects the liquid levels in the mixing tank and equalization tank, collects the liquid level in the metering tank, and converts the liquid levels into volume.

[0148] S42: After the drilling water volume in the metering tank reaches the fifth set volume, start the clean water pump and the standby clean water pump, increase the speed of the left engine and the right engine, and clean the pipelines where the fifteenth valve 15, the sixth valve 6, and the eighth valve 8 are located, as well as the pipelines where the fourteenth valve, the standby clean water pump and the eighth valve are located for a total of a seventh set time; and after cleaning for the seventh set time, stop the clean water pump and the standby clean water pump. The seventh set time is 5 seconds, and the fifth set volume is 10BBL.

[0149] For step S42, increasing the speed of the left and right engines specifically means increasing the speed of both engines to 1600 rpm. The specific flow path of the liquid during cleaning of the pipelines containing valves 15, 6, and 8, as well as valves 14, the backup clean water pump, and valve 8, is as follows: the drilling water in the metering tank flows into the pipelines containing valves 14 and 15 through valves 11 and 12; the liquid flowing through valve 15 passes through the clean water pump, valve 6, valve 8, and valve 21, and finally exits through valve 39 from the drain outlet; the liquid flowing through valve 14 merges with the liquid flowing through valve 15 via the backup clean water pump.

[0150] S43: Fill the metering tank with drilling water, and close the fourth valve 4 after filling the metering tank with drilling water.

[0151] S44: Open valve 26 (26) and valve 22 (22), close valve 39 (39), leaving the other valves unchanged. Start the clean water pump and the standby clean water pump to allow drilling water in the metering tank to enter the equalization tank through valve 26 (26) and valve 22 (22) to flush valve 22 (22); close valve 22 (22), open valve 25 (25) to allow drilling water in the metering tank to enter the mixing tank through valve 26 (26) and valve 25 (25) to flush valve 25 (25); and close valve 25 (26) and valve 27 (28) (29). 26. Open valves 23 and 32 to allow drilling water in the metering tank to enter the equalization tank through valve 32 and the circulation pump, thereby flushing valve 23; and close valve 23 and open valve 24 to allow drilling water in the metering tank to enter the mixing tank through valve 32 and the circulation pump, thereby flushing valve 24; wherein valves 22, 23, 24, and 25 are flushed for an eighth set time; the eighth set time is 5 seconds. In this embodiment, the valve opening and closing follows the principle of opening first and then closing.

[0152] S45: Open valves 26, 22, 23, and 25. Use the clean water pump and the standby clean water pump to pump all the remaining drilling water in the metering tank to the equalization tank and the mixing tank. After pumping all the remaining drilling water in the metering tank to the equalization tank and the mixing tank, stop the clean water pump and the standby clean water pump. Set the left engine and the right engine to idle speed.

[0153] In step S45, valves 26, 22, 23, and 25 are opened. The remaining drilling water in the metering tank is pumped to the equalization tank and mixing tank using the clean water pump and the standby clean water pump. After all the remaining drilling water in the metering tank has been pumped to the equalization tank and mixing tank, the clean water pump and the standby clean water pump are stopped. The left and right engines are then set to idle speed. The method further includes: opening the circulation pipeline valves, opening the corresponding valves of the cement slurry injection pipeline, and opening the clean water proportioning valve B1, valve 9, valve 8, valve 33, valve 28, and valve 29. Valves 19, 20, 21, 26, 23, 25, 38, and 35 are turned off. The remaining valves are closed. The circulation pump and injection pump are turned on, and the speed of the left and right engines is increased. The drilling water in the equalization tank and mixing tank is used to clean the pipelines for the ninth set time. The pipelines to be cleaned include the circulation pipeline, the cement slurry injection pipeline, the spare cement slurry injection pipeline, and the pipeline where valve 26 is located. After cleaning, the circulation pump and injection pump are turned off, and the left and right engines are set to idle speed. The ninth set time is 30 seconds.

[0154] Regarding step S4, it should also be noted that in order to ensure sufficient water supply in the metering tank, the following should be done: when the liquid level in the metering tank is below 20%, the opening of the clean water proportional valve should be appropriately reduced; when the liquid level in the metering tank reaches 40%, the clean water proportional valve should be gradually adjusted to the maximum; and when the liquid level in the metering tank reaches 90%, the fourth valve 4 should be closed in advance.

[0155] Finally, to prevent the equalization tank from evacuating or overflowing, the following measures are also necessary: ​​When the equalization tank level is below 10%, open valve 28 (28) and close valve 32 (32) to allow the liquid discharged from the injection pump to return to the mixing tank through valve 28 (28); when the equalization tank level is above 70%, open valve 32 (32) and close valve 28 (28) to restore normal operation; when the equalization tank level reaches 80%, appropriately reduce the opening of the clear water proportioning valve. During valve switching, follow the principle of opening the valve before closing it to avoid pump stalling.

[0156] The process then proceeds to step S5, which involves cleaning. In step S5, based on the levels in the metering tank and mixing tank, as well as the running time, valves are opened / closed, and the circulation pump and injection pump are started / stopped. The engine speed and transmission gear are adjusted to flush the large and small circulation pipelines. Subsequently, the corresponding valves are opened to drain the manifold, thus completing the cleaning process.

[0157] Specifically, such as Figure 9 As shown, step S5, which uses drilling water from the equalization tank and mixing tank to clean the large circulation pipeline and uses drilling water from the right metering tank to clean the small circulation pipeline, further includes:

[0158] S51: Open the corresponding valves in the main circulation pipeline, including valves 23, 24, 27, 31, 25, and 38, and close the remaining valves; increase the speed of the left engine and start the circulation pump to circulate the liquid between the mixing tank and the circulation pipeline valves; after starting the circulation pump for 20 seconds, open valve 34; when the liquid level in the mixing tank is below 12 inches, stop the circulation pump and reduce the left engine to idle speed.

[0159] In this embodiment, the opening of each valve can be achieved through a PLC controller. Before step S51, the PLC controller receives cleaning setting parameters set on the HMI, collects the liquid levels of the mixing tank and equalization tank, collects the liquid levels of the left and right metering tanks, and converts them into volume. Among them, the pipelines containing the 22nd valve 22, 30th valve 30, 32nd valve 32, 17th valve 17, 18th valve 18, 40th valve 40, 10th valve 10, 3rd plug valve P3, 4th plug valve P4, 5th plug valve P5, 6th plug valve P6, 7th plug valve P7, and 8th plug valve P8 are the main circulation pipelines.

[0160] S52: Start the injection pump, increase the speed of the left and right engines, and discharge the liquid in the mixing tank and equalization tank through the large circulation pipeline to clean the large circulation pipeline. When 10% of the liquid remains in the mixing tank and equalization tank, reduce the speed of the left and right engines to idle and stop the injection pump.

[0161] After starting the injection pump in step S52, since there are gearboxes between the left engine and the left piston pump, and between the right engine and the right piston pump, it is necessary to engage third gear in both gearboxes to increase the speed of the right engine to 1600 rpm, and the speed of the left engine to 1600 rpm. The purpose of step S52 is to drain the liquid in the mixing tank and the equalization tank through the large circulation pipeline to clean the large circulation pipeline.

[0162] Step S52: Start the injection pump, increase the speed of the left and right engines, and discharge the liquid in the mixing tank and equalization tank through the large circulation pipeline to clean the large circulation pipeline until 10% of the liquid remains in the mixing tank and equalization tank. Then, reduce the speed of the left and right engines to idle and stop the injection pump. Specifically, this includes:

[0163] S521: Start the injection pump, increase the speed of the left and right engines, and discharge the liquid in the mixing tank and equalization tank through the large circulation pipeline. Clean for the tenth set time, which is 10 seconds. During this period, the liquid flows through the following valves: valve 22 / valve 25, valves on the injection pump and the large circulation pipeline. Finally, the liquid is discharged through the tenth valve of the left metering tank.

[0164] S522: Close the sixth stopcock valve P6 and clean for the eleventh set time again. The eleventh set time is 15s. In this embodiment, after closing the sixth stopcock valve P6, the cleaning liquid flows into the left metering tank through the seventh stopcock valve P7 and the eighth stopcock valve P8, thus achieving the purpose of focusing on cleaning the seventh stopcock valve P7.

[0165] S523: Open the sixth stopcock valve P6 and close the seventh stopcock valve P7. Perform the third cleaning at the eleventh set time. In this embodiment, after closing the seventh stopcock valve P7, the cleaning liquid flows into the left metering tank through the sixth stopcock valve P6 and the eighth stopcock valve P8, thus achieving the purpose of focusing on cleaning the sixth stopcock valve P6.

[0166] S524: Open the seventh stop valve P7 to continue cleaning until the liquid in the mixing tank and equalization tank is 10% remaining. Then, reduce the left and right engines to idle speed and stop the injection pump.

[0167] Step S53: Add the sixth set volume of drilling water to the right metering tank, open the valve containing the small circulation pipeline, close the other valves, and increase the speed of the left and right engines to use the drilling water in the right metering tank to clean the small circulation pipeline until the liquid in the right metering tank is 10% full. Then, reduce the speed of the left and right engines to idle. The sixth set volume is 9 BBL. This embodiment achieves the purpose of using the drilling water in the right metering tank to clean the small circulation pipeline.

[0168] For S53, both transmissions need to be engaged in third gear, increasing the right engine speed to 1600 rpm and the left engine speed to 1600 rpm. The purpose of step S53 is to drain the liquid in the right metering tank through the small circulation line to clean the small circulation line.

[0169] Furthermore, after cleaning the large circulation pipeline with drilling water from the equalization tank and the mixing tank in step S5, and cleaning the small circulation pipeline with drilling water from the right metering tank, the method also includes draining the remaining liquid from the equalization tank, the mixing tank, and the right metering tank.

[0170] The process of draining the remaining liquid from the equalization tank, mixing tank, and right metering tank involves the following steps: closing valves 1, 2, 3, 4, 5, and 36; keeping plug valves P1 and P2 closed; and opening the remaining valves to drain the remaining liquid from the mixing tank, equalization tank, and right metering tank. After draining the remaining liquid from these three tanks, the cleaning of the cementing mixing equipment is complete.

[0171] The cleaning method of this invention greatly reduces the labor intensity of operators; the cleaning method of this invention can effectively reduce the amount of cleaning water and improve cleaning efficiency; the cleaning method of this invention adopts a combination of manual / automatic operation and computer control with manual operation, which can target and repeatedly clean key parts, and can effectively solve the problem of incomplete cleaning of components such as densitometers.

[0172] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A method of cleaning a cementing slurry plant, characterized in that, The method comprises the following steps: blowing the remaining cement ash in the constant pressure tank to the high-energy mixer, mixing the remaining cement ash with seawater, and discharging the mixed cement ash from the sewage outlet through the twenty-first valve (21) and the thirty-ninth valve (39); cleaning the pipeline where the circulating density meter is located and the pipeline where the booster density meter is located by using the seawater in the metering tank; the pipeline where the circulating density meter is located is the pipeline of the circulating density meter flushing ball valve, the circulating density meter, the thirty-first valve (31) to the thirty-fourth valve (34); the pipeline where the booster density meter is located is the pipeline from the booster density meter flushing ball valve to the booster density meter; cleaning the circulating pipeline, the cement slurry manifold, and the pipeline from the twenty-first valve to the sewage outlet, and discharging the remaining liquid in the mixing tank and the equalizing tank from the sewage outlet through the twenty-first valve (21) and the thirty-ninth valve (39) by using the circulating pump after the cleaning is completed; the cement slurry manifold comprises the cement slurry injection pipeline, the pipeline where the twenty-third valve (23), the twenty-ninth valve (29), and the thirty-third valve (33) are located, the pipeline where the twenty-sixth valve (26) is located, the pipeline where the sixteenth valve (16) and the eleventh valve (11) are located, the pipeline where the sixteenth valve (16) and the twelfth valve (12) are located, and the pipeline from the twenty-first valve to the sewage outlet; cleaning the pipeline where the fifteenth valve (15), the fresh water pump, the sixth valve (6), and the eighth valve (8) are located by using the drilling water in the metering tank, cleaning the pipeline where the fourteenth valve, the standby fresh water pump, and the eighth valve are located, cleaning the valves at the outlets of the mixing tank and the equalizing tank, and pumping all the remaining liquid in the metering tank to the equalizing tank and the mixing tank; cleaning the large circulating pipeline by using the drilling water in the equalizing tank and the mixing tank, and cleaning the small circulating pipeline by using the drilling water in the right metering tank.

2. The method of claim 1, wherein, The step of blowing the remaining cement ash in the constant pressure tank to the high-energy mixer, mixing the remaining cement ash with seawater, and discharging the mixed cement ash from the sewage outlet through the twenty-first valve (21) and the thirty-ninth valve (39) further comprises the following steps: opening the fresh water pump to the ash discharge head valve, opening the first valve (1), the second valve (2), the third valve (3), the nineteenth valve (19), the twentieth valve (20), and the twenty-first valve (21), opening the corresponding valves on the cement slurry injection pipeline, opening the circulating pipeline valve, opening the thirty-ninth valve (39), and closing the remaining valves; adding seawater to the metering tank through the first valve, the second valve, and the third valve, opening the fresh water proportional valve (B1) when the seawater added to the metering tank reaches a first set volume, increasing the rotating speed of the left engine, and opening the fresh water pump to pump the seawater in the metering tank to the mixing tank through the high-energy mixer, wherein the first set volume is 10 BBL; opening the ash discharge proportional valve (B2) and the thirty-sixth valve (36) to blow the remaining cement ash in the constant pressure tank to the high-energy mixer; opening the circulating pump to circulate the liquid between the mixing tank and the circulating pipeline valve when the liquid level in the mixing tank reaches a first set liquid level, wherein the first set liquid level is 5 inches. After the liquid level in the equalization tank reaches a second set liquid level, the grouting pump is started, the speed of the right engine is increased, and the mixed cement slurry is discharged from the blowdown outlet through the cement slurry grouting pipeline and the thirty-ninth valve (39), and the second set liquid level is 27 inches; The thirty-sixth valve (36) is closed after a first set time delay when the residual cement ash in the constant pressure tank reaches a set value, the first set time is 20 s, and the set value is 100 lb; The speed of the left engine is reduced to idle speed, the clean water pump and the circulating pump are stopped, the third valve (3) is closed, the twenty-fifth valve (25) and the thirty-eighth valve (38) are opened, the remaining liquid in the mixing tank and the equalization tank is discharged from the blowdown outlet through the cement slurry grouting pipeline, the twenty-first valve and the thirty-ninth valve (39) by the grouting pump, and the right engine is reduced to idle speed after the remaining liquid in the mixing tank and the equalization tank reaches a minimum set value, and the grouting pump is stopped; and the minimum set value is 5 inches.

3. The method of claim 2, wherein, The opening of the ash proportioning valve (B2) and the thirty-sixth valve (36) to blow the residual cement ash in the constant pressure tank to the high-energy mixer specifically includes the following steps: the ash proportioning valve (B2) is opened to 50% opening, and the thirty-sixth valve (36) is opened to blow the residual cement ash in the constant pressure tank to the high-energy mixer after a second set time delay, the ash proportioning valve (B2) is opened to 100% opening when the residual cement ash in the constant pressure tank reaches the set value, and the second set time is 3 s.

4. The method of claim 2, wherein, After the thirty-sixth valve (36) is closed after a first set time delay when the residual cement ash in the constant pressure tank reaches a set value, the method further includes the following steps: the air blowing valve (B3) is opened, the residual cement ash in the pipeline is blown to the high-energy mixer by using the air source, and the air blowing valve (B3) is closed after there is no residual cement ash in the pipeline.

5. The method of claim 2, wherein, The pipelines in which the circulating density meter and the booster density meter are located are further cleaned by using seawater in the metering tank, and the pipelines in which the circulating density meter and the booster density meter are located are further cleaned by using seawater in the metering tank. The thirty-fifth valve (35) is closed, the third valve (3) and the twenty-sixth valve (26) are opened, and the states of the remaining valves remain unchanged; Seawater is added to the metering tank through the first valve, the second valve and the third valve, the clean water pump is started after the amount of seawater in the metering tank reaches a second set volume, the speed of the left engine is increased, and the circulating density meter flushing ball valve is opened to clean the pipeline in which the circulating density meter is located, and the second set volume is 9 BBL; The booster density meter flushing ball valve is opened to discharge liquid from the blowdown outlet through the seventeenth valve, the eighteenth valve, the nineteenth valve, the twentieth valve, the twenty-first valve (21) and the thirty-ninth valve (39) to clean the pipeline in which the booster density meter is located; After the amount of cleaning water reaches a third set volume, the clean water pump is stopped, and the left engine is reduced to idle speed, and the third set volume is 15 BBL.

6. The method of claim 5, wherein, After the amount of cleaning water reaches a third set volume, the clean water pump is stopped, and the left engine is reduced to idle speed, the method further includes the following steps: The ash head and the diffusion tank are cleaned, and the residual cement slurry in the mixing tank and the equalization tank is discharged from the blowdown outlet through the twenty-sixth valve (26) and the thirty-ninth valve (39).

7. The method of claim 1, wherein, The cleaning cycle pipeline, cement slurry manifold and the twenty-first valve to the blow-off pipeline, and after the cleaning is completed, the remaining liquid in the mixing tank and the equalizing tank is discharged from the blow-off through the twenty-first valve (21) and the thirty-ninth valve (39) by the circulating pump further comprises: opening the clean water pump to the ash head valve, opening the first valve, the second valve, the third valve, the nineteenth valve, the twentieth valve and the twenty-first valve, opening the circulating pipeline valve, opening the corresponding valve on the cement slurry filling pipeline, and closing the remaining valves; adding seawater into the metering tank through the first valve, the second valve and the third valve, when the seawater in the metering tank reaches the fourth set volume, opening the clean water proportional valve (B1), increasing the speed of the left engine, and starting the clean water pump to pump the seawater in the metering tank to the mixing tank, and the fourth set volume is 10 BBL; when the liquid level in the mixing tank reaches the third set liquid level, starting the circulating pump to circulate the liquid between the mixing tank and the circulating pipeline valve to clean the circulating pipeline; and the third set liquid level is 15 inches; when the liquid level in the equalizing tank reaches the fourth set liquid level, starting the filling pump, opening the thirty-ninth valve (39), increasing the speed of the right engine, and making the liquid discharge from the blow-off through the corresponding valve on the cement slurry filling pipeline, the twenty-first valve and the thirty-ninth valve (39) to clean the cement slurry filling pipeline, and the cleaning time is the third set time; the fourth set liquid level is 27 inches, and the third set time is 20 s; opening the thirty-third valve, the twenty-third valve, the twenty-fifth valve (25), the twenty-eighth valve (28), the twenty-ninth valve and the thirty-eighth valve (38), closing the thirty-second valve (32), the twenty-second valve (22), the twenty-fourth valve (24), the twenty-seventh valve (27) and the thirtieth valve (30), and the state of the remaining valves is unchanged, cleaning the pipeline where the twenty-third valve (23), the twenty-ninth valve (29) and the thirty-third valve (33) are located for the fourth set time, and the fourth set time is 30 s; stopping the clean water pump, closing the third valve (3), opening the tenth valve (10) and the thirteenth valve (13) to discharge the remaining liquid in the metering tank; stopping the filling pump, reducing the right engine to idle, opening the twenty-sixth valve (26), closing the thirty-ninth valve (39), and cleaning the pipeline where the twenty-sixth valve (26) is located by the circulating pump for the fifth set time; and the fifth set time is 10 s; opening the sixteenth valve (16), closing the twenty-sixth valve (26) and the twelfth valve (12), cleaning the pipeline where the sixteenth valve (16) and the eleventh valve (11) are located, closing the eleventh valve (11), opening the twelfth valve (12), cleaning the pipeline where the sixteenth valve (16) and the twelfth valve (12) are located for the sixth set time, and opening the eleventh valve (11) after the cleaning; and the sixth set time is 3 s; After the cleaning, the thirty-ninth valve (39) is opened, the sixteenth valve (16) is closed, and the remaining liquid in the mixing tank and the equalizing tank is discharged from the blow-off port through the twenty-first valve and the thirty-ninth valve (39) by using the circulating pump to clean the pipeline from the twenty-first valve to the blow-off port, and after the remaining liquid is completely discharged, the circulating pump is stopped, and the left engine is reduced to idle speed.

8. The method of claim 7, wherein, The thirty-third valve, the twenty-third valve, the twenty-fifth valve (25), the twenty-eighth valve (28), the twenty-ninth valve and the thirty-eighth valve (38) are opened, the thirty-second valve (32), the twenty-second valve (22), the twenty-fourth valve (24), the twenty-seventh valve (27) and the thirtieth valve (30) are closed, and the remaining valves remain unchanged, and the fourth setting time for cleaning the pipelines in which the twenty-third valve (23), the twenty-ninth valve (29) and the thirty-third valve (33) are located is specifically: The thirty-third valve, the twenty-third valve, the twenty-fifth valve (25), the twenty-eighth valve (28), the twenty-ninth valve and the thirty-eighth valve (38) are opened, the thirty-second valve (32), the twenty-second valve (22), the twenty-fourth valve (24), the twenty-seventh valve (27) and the thirtieth valve (30) are closed, and the remaining valves remain unchanged; The seventeenth valve (17) and the nineteenth valve (19) are closed, and the pipeline in which the twenty-third valve, the twenty-ninth valve and the thirty-third valve are located is cleaned by using the circulating pump for 15s; the seventeenth valve (17) and the nineteenth valve (19) are opened, the eighteenth valve (18) and the twentieth valve (20) are closed, and the pipeline in which the twenty-third valve, the twenty-ninth valve and the thirty-third valve are located is cleaned by using the circulating pump for 15s; During the process of closing the seventeenth valve (17) and the nineteenth valve (19) and during the process of closing the eighteenth valve (18) and the twentieth valve (20), the liquid in the mixing tank is again flowed into the mixing tank through the twenty-fifth valve, the perfusion pump and the twenty-eighth valve by using the perfusion pump, and after the cleaning, the eighteenth valve (18) and the twentieth valve (20) are opened.

9. The method of claim 7, wherein, After the cleaning, the thirty-ninth valve (39) is opened, the sixteenth valve (16) is closed, and the remaining liquid in the mixing tank and the equalizing tank is discharged from the blow-off port through the twenty-first valve and the thirty-ninth valve (39) by using the circulating pump to clean the pipeline from the twenty-first valve to the blow-off port, and after the remaining liquid is completely discharged, the circulating pump is stopped, and the left engine is reduced to idle speed. After the remaining liquid in the metering tank is completely discharged, the tenth valve (10) and the thirteenth valve (13) are closed.

10. The method of claim 1, wherein, After the cleaning of the pipeline, the cement slurry manifold and the pipeline from the twenty-first valve to the blow-off port, and after the remaining liquid in the mixing tank and the equalizing tank is discharged from the blow-off port through the twenty-first valve (21) and the thirty-ninth valve (39) by using the circulating pump, the method further comprises: After the remaining liquid in the metering tank is completely discharged, the tenth valve (10) and the thirteenth valve (13) are closed. After the cleaning of the pipeline, the cement slurry manifold and the pipeline from the twenty-first valve to the blow-off port, and after the remaining liquid in the mixing tank and the equalizing tank is discharged from the blow-off port through the twenty-first valve (21) and the thirty-ninth valve (39) by using the circulating pump, the method further comprises: opening the first valve and the fourth valve to fill the right measuring tank with drilling fluid, and closing the first valve after the right measuring tank is filled, opening the second valve to fill the left measuring tank with drilling fluid, and closing the second valve after the left measuring tank is filled.

11. The method of claim 1, wherein, the cleaning of the pipelines where the fifteenth valve (15), the clean water pump, the sixth valve (6) and the eighth valve (8) are located, the cleaning of the pipelines where the fourteenth valve, the standby clean water pump and the eighth valve are located, the cleaning of the valves at the outlet of the mixing tank and the equalizing tank, and the pumping of the remaining liquid in the measuring tank into the equalizing tank and the mixing tank further comprise: opening the eleventh valve (11), the twelfth valve (12), the fifteenth valve (15), the sixth valve (6), the eighth valve (8), the fourteenth valve (14), the seventeenth valve (17), the eighteenth valve (18), the nineteenth valve (19), the twentieth valve (20), the twenty-first valve (21) and the thirty-ninth valve (39), and closing the rest of the valves; after the volume of drilling fluid in the measuring tank reaches a fifth set volume, starting the clean water pump and the standby clean water pump, increasing the rotation speed of the left engine and the right engine, cleaning the pipelines where the fifteenth valve (15), the sixth valve (6) and the eighth valve (8) are located, and the pipelines where the fourteenth valve, the standby clean water pump and the eighth valve are located for a seventh set time, and stopping the clean water pump and the standby clean water pump after the seventh set time, wherein the seventh set time is 5s, and the fifth set volume is 10BBL; filling the measuring tank with drilling fluid, and closing the fourth valve (4) after the measuring tank is filled with drilling fluid; opening the twenty-sixth valve (26) and the twenty-second valve (22), closing the thirty-ninth valve (39), and keeping the rest of the valves unchanged, starting the clean water pump and the standby clean water pump, and making the drilling fluid in the measuring tank enter the equalizing tank through the twenty-sixth valve (26) and the twenty-second valve (22) to flush the twenty-second valve (22); closing the twenty-second valve (22), opening the twenty-fifth valve (25), and making the drilling fluid in the measuring tank enter the mixing tank through the twenty-sixth valve (26) and the twenty-fifth valve (25) to flush the twenty-fifth valve (25); closing the twenty-fifth valve (25) and the twenty-sixth valve (26), opening the twenty-third valve (23) and the thirty-second valve (32), and making the drilling fluid in the measuring tank enter the equalizing tank through the thirty-second valve (32) and the circulating pump to flush the twenty-third valve (23); and closing the twenty-third valve (23), opening the twenty-fourth valve (24), and making the drilling fluid in the measuring tank enter the mixing tank through the thirty-second valve (32) and the circulating pump to flush the twenty-fourth valve (24); wherein the twenty-second valve (22), the twenty-third valve (23), the twenty-fourth valve (24) and the twenty-fifth valve (25) each flush for an eighth set time, and the eighth set time is 5s; filling the measuring tank with drilling fluid, and closing the fourth valve (4) after the measuring tank is filled with drilling fluid; Open the twenty-sixth valve (26), the twenty-second valve (22), the twenty-third valve (23) and the twenty-fifth valve (25), use the clean water pump and the standby clean water pump to pump all the remaining drilling water in the metering tank to the equalizing tank and the mud tank, and stop the clean water pump and the standby clean water pump after pumping all the remaining drilling water in the metering tank to the equalizing tank and the mud tank, and adjust the left engine and the right engine to idle speed.

12. The method of claim 11, wherein, After the twenty-sixth valve (26), the twenty-second valve (22), the twenty-third valve (23) and the twenty-fifth valve (25) are opened, all the remaining drilling water in the metering tank is pumped to the equalizing tank and the mud tank by the clean water pump and the standby clean water pump, and the clean water pump and the standby clean water pump are stopped after pumping all the remaining drilling water in the metering tank to the equalizing tank and the mud tank, and the left engine and the right engine are adjusted to idle speed, the method further comprises: Open the circulation pipeline valve, open the corresponding valve of the cement slurry filling pipeline, open the clean water proportional valve (B1), the ninth valve (9), the eighth valve (8), the thirty-third valve (33), the twenty-eighth valve (28), the twenty-ninth valve (29), the nineteenth valve, the twentieth valve, the twenty-first valve, the twenty-sixth valve (26), the twenty-third valve (23), the twenty-fifth valve (25), the thirty-eighth valve (38) and the thirty-fifth valve (35), close the remaining valves, open the circulation pump and the filling pump, and raise the speed of the left engine and the right engine, use the drilling water in the equalizing tank and the mud tank to clean for the ninth set time, the pipelines to be cleaned include the circulation pipeline, the cement slurry filling pipeline, the standby cement slurry filling pipeline and the pipeline where the twenty-sixth valve (26) is located, and after cleaning, stop the circulation pump and the filling pump, and adjust the left engine and the right engine to idle speed; the ninth set time is 30 seconds.

13. The method of claim 1, wherein, The use of the drilling water in the equalizing tank and the mud tank to clean the large circulation pipeline, and the use of the drilling water in the right metering tank to clean the small circulation pipeline further comprises: Open the corresponding valve of the large circulation pipeline, open the twenty-third valve (23), the twenty-fourth valve (24), the twenty-seventh valve (27), the thirty-first valve (31), the twenty-fifth valve (25) and the thirty-eighth valve (38), and close the remaining valves; raise the speed of the left engine, start the circulation pump to make the liquid circulate between the mud tank and the circulation pipeline valve; open the thirty-fourth valve after starting the circulation pump for 20s, stop the circulation pump when the liquid level of the mud tank is lower than 12 inches, and lower the left engine to idle speed; Start the filling pump, raise the speed of the left engine and the right engine, make the liquid in the mud tank and the equalizing tank discharge through the large circulation pipeline to clean the large circulation pipeline, and when the liquid in the mud tank and the equalizing tank is left by 10%, lower the left engine and the right engine to idle speed, and stop the filling pump; Add the sixth set volume of drilling water into the right metering tank, open the valve of the small circulation pipeline, close the remaining valves, raise the speed of the left engine and the right engine to use the drilling water in the right metering tank to clean the small circulation pipeline, and when the liquid in the right metering tank is left by 10%, lower the right engine to idle speed, and the sixth set volume is 9BBL.

14. The method of claim 13, wherein, After the method of cleaning the large circulation pipeline by using the drilling water in the equalization tank and the slurry tank, and cleaning the small circulation pipeline by using the drilling water in the right metering tank, the method further comprises: draining the residual liquid in the equalization tank, the slurry tank and the right metering tank; The draining of the residual liquid in the equalization tank, the slurry tank and the right metering tank specifically comprises: closing the first valve (1), the second valve (2), the third valve (3), the fourth valve (4), the fifth valve (5) and the thirty-sixth valve (36), keeping the first plug valve (P1) and the second plug valve (P2) closed, opening the remaining valves, draining the residual liquid in the slurry tank and the equalization tank, and draining the residual liquid in the right metering tank.

15. The method of claim 13, wherein, The starting of the perfusion pump, the increasing of the rotating speed of the left engine and the right engine, the draining of the liquid in the slurry tank and the equalization tank through the large circulation pipeline to clean the large circulation pipeline, and the decreasing of the rotating speed of the left engine and the right engine to idle speed when the liquid in the slurry tank and the equalization tank is 10% left, and the stopping of the perfusion pump specifically comprise: The starting of the perfusion pump, the increasing of the rotating speed of the left engine and the right engine, the draining of the liquid in the slurry tank and the equalization tank through the large circulation pipeline to clean the large circulation pipeline for a tenth set time, the tenth set time being 10s; The closing of the sixth plug valve (P6), the cleaning for an eleventh set time again, the eleventh set time being 15s; The opening of the sixth plug valve (P6), the closing of the seventh plug valve (P7), the cleaning for the eleventh set time for the third time; The opening of the seventh plug valve (P7) to continue cleaning, and the decreasing of the rotating speed of the left engine and the right engine to idle speed when the liquid in the slurry tank and the equalization tank is 10% left, and the stopping of the perfusion pump.

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