Automatic control continuous circulation drilling system and method

Abstract

The invention relates to an automatic control continuous circulation drilling system and method. The system comprises a circulation short section, a drill rod, a main circulation pipeline, a side circulation pipeline, a flow dividing manifold system, a liquid supplementing pump, a liquid supplementing pipeline, a slurry pump, a pressure relief pipeline and a slurry pool. A main circulation channel, a side circulation channel, a liquid supplementing channel, a pressure relief channel and an emergency channel are arranged in the flow dividing manifold system, and a circulation short section is connected with a drill rod and connected with a main circulation pipeline and a side circulation pipeline. A main circulation outlet of the main circulation channel is connected with a main circulation pipeline, a side circulation outlet of the side circulation channel is connected with a side circulation pipeline, a liquid supplementing inlet of the liquid supplementing channel is connected with a liquid supplementing pipeline and a liquid supplementing pump, a slurry inlet in the flow dividing manifold system is connected with a slurry pump, and the liquid supplementing pump and the slurry pump are connected with a slurry pool. A pressure relief outlet of the pressure relief channel is sequentially connected with a pressure relief pipeline and a mud pit, an inlet of the emergency channel is a mud inlet, and an outlet is a main circulation outlet. According to the invention, human intervention is not needed, and the safety of continuous cycle operation is improved.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas well drilling technology, specifically relating to an automatic control continuous circulation drilling system and method. Background Technology

[0002] Continuous circulation drilling technology can solve various problems caused by frequent pump starts in conventional drilling technology. It can maintain drilling fluid circulation during the drilling and string connection process, achieve continuous drilling, maintain bottom hole pressure for a long time, keep the drilling fluid equivalent density stable, and continuously carry the bottom hole cuttings to the surface, effectively preventing cuttings accumulation.

[0003] However, most existing continuous circulation technologies require manual operation, including switching circulation channels and connecting side circulation operations. These operations require the cooperation of multiple operators, increasing operational complexity; accidents during operation can cause serious personal injury, and operator training is required, increasing labor costs; furthermore, the unpredictable operation time increases time costs. During pipeline switching in continuous circulation technology, the water hammer effect in the manifold causes significant damage to valves, severely impacting the service life of the continuous circulation equipment. Summary of the Invention

[0004] To address all or part of the aforementioned problems, the present invention aims to provide an automatic control continuous circulation drilling system and method that can automatically switch the main and side circulation channels in continuous circulation technology without human intervention. The system can provide real-time data during continuous circulation operations, and operators only need to operate the control cabinet to complete the entire process, thereby improving the safety of continuous circulation operations.

[0005] According to a first aspect of the present invention, an automatic control continuous circulation drilling system is provided, comprising a circulation sub, drill pipe, main circulation pipeline, side circulation pipeline, diversion manifold system, replenishment pump, replenishment pipeline, mud pump, pressure relief pipeline, and mud pit; the diversion manifold system is provided with a main circulation channel, a side circulation channel, a replenishment channel, a pressure relief channel, and an emergency channel, wherein: the circulation sub is connected to the drill pipe, and simultaneously connected to the main circulation pipeline and the side circulation pipeline; the main circulation outlet of the main circulation channel is connected to the main circulation pipeline, the side circulation outlet of the side circulation channel is connected to the side circulation pipeline, the replenishment inlet of the replenishment channel is connected to the replenishment pipeline and the replenishment pump, the mud inlet on the diversion manifold system is connected to the mud pump, the replenishment pump and the mud pump are connected to the mud pit, the pressure relief outlet of the pressure relief channel is sequentially connected to the pressure relief pipeline and the mud pit, the inlet of the emergency channel is the mud inlet, and the outlet of the emergency channel is the main circulation outlet.

[0006] In some embodiments, the circulation manifold includes a main valve and a side valve. The main valve is connected to the main circulation pipeline, and the side valve is connected to the side circulation pipeline. The liquid pressure difference during the switching of the manifold system channels enables the opening and closing of the main valve and the side valve within the circulation manifold.

[0007] In some embodiments, the manifold system includes a control cabinet and a manifold, which forms a main circulation channel, a side circulation channel, a replenishment channel, a pressure relief channel, and an emergency channel. Electric throttle valves and electric gate valves are installed on the main circulation channel and the side circulation channel, and electric gate valves are installed on the replenishment channel, the emergency channel, and the pressure relief channel.

[0008] In some embodiments, pressure sensors are installed on the main circulation channel, side circulation channel, replenishment channel, pressure relief channel, and emergency channel. The control cabinet is configured to receive data from the pressure sensors and issue commands to the electric throttle valve and electric gate valve after the pressure conditions for opening or closing the gate are met, thereby performing control.

[0009] In some embodiments, the pressure condition for opening or closing the gate is set to ensure that the pressure sensor reading remains stable at a preset value.

[0010] In some embodiments, an auxiliary connection device is also included, which is used to move the side circulation line to the front of the circulation stub.

[0011] According to a second aspect of the present invention, an automatic control continuous circulation drilling method is provided, applied to the aforementioned automatic control continuous circulation drilling system. The method includes the following steps: main circulation, side circulation fluid replenishment, main circulation to side circulation, side circulation, main circulation fluid replenishment, side circulation to main circulation, and main circulation, wherein:

[0012] Main circulation: Before the drill pipe is lowered into the ground, the mud pump pumps the drilling fluid into the manifold system. The electric gate valve and electric throttle valve of the main circulation channel of the manifold system are opened, and the drilling fluid completes the drilling fluid circulation through the main circulation pipeline, and the drilling begins.

[0013] Side circulation fluid replenishment: After the drill pipe is lowered into the ground, before connecting the column, connect the outlet of the side circulation pipeline to the side valve of the circulation subsection above the drill pipe, open the electric gate valve of the fluid replenishment channel of the shunt manifold, and the fluid replenishment pump replenishes the side circulation pipeline through the fluid replenishment pipeline until the predetermined pressure value is reached. Then close the electric gate valve of the fluid replenishment channel.

[0014] Main circulation to side circulation: The control cabinet issues a command, the electric gate valve of the side circulation channel opens, the electric throttle valve gradually opens, the electric throttle valve of the main circulation channel gradually closes, and after the drilling fluid pressure stabilizes, the electric gate valve of the main circulation channel closes.

[0015] Side circulation: Initially, the drilling fluid is connected to the standpipe and circulated through the side circulation pipeline.

[0016] Main circulation replenishment: After the column is connected, the main circulation pipeline is connected. The control cabinet issues a command to open the electric gate valve of the replenishment channel of the branch manifold to replenish the main circulation pipeline to the predetermined pressure value, and then closes the electric gate valve of the replenishment channel.

[0017] Side circulation to main circulation: Open the electric gate valve of the main circulation channel, gradually open the electric throttle valve of the main circulation channel to the maximum, gradually close the electric throttle valve of the side circulation channel to the minimum, and close the electric gate valve of the side circulation channel after the drilling fluid pressure stabilizes.

[0018] Main circulation: The drilling fluid circulates through the main circulation pipeline to continue drilling operations, repeating the above operations.

[0019] In some embodiments, the main circulation to side circulation switch further includes: when the main circulation is switched to side circulation, the electric throttle valve of the main circulation channel of the manifold gradually closes, the liquid pressure in the main circulation line decreases, the electric throttle valve of the side circulation channel gradually increases, the liquid pressure in the side circulation line increases, and the main valve closes and the side valve opens due to the pressure difference in the circulation sub, so that the drilling fluid circulates through the side circulation channel of the circulation sub.

[0020] In some embodiments, the process of switching from side circulation to main circulation further includes: when switching from side circulation to main circulation, the pressure in the side circulation pipeline decreases and the pressure in the main circulation pipeline increases. Due to the pressure difference, the main valve in the circulation section will open and the side valve will close. The main circulation passage 51 in the circulation section will be closed and the side circulation passage will be opened.

[0021] In some embodiments, the automatic control continuous circulation drilling method further includes: main circulation depressurization: opening the electric gate valve on the depressurization channel connected to the main circulation channel, allowing the drilling fluid in the main circulation to return to the mud pit through the depressurization pipeline, reducing the pressure to a minimum, and then closing the electric gate valve on the depressurization channel connected to the main circulation channel and disconnecting the main circulation pipeline; side circulation depressurization: opening the electric gate valve on the depressurization channel connected to the side circulation channel, allowing the side circulation drilling fluid to return to the mud pit through the depressurization pipeline, reducing the pressure to a minimum, and then closing the electric gate valve on the depressurization channel connected to the side circulation channel and disconnecting the side circulation pipeline.

[0022] As can be seen from the above technical solution, the automatic control continuous circulation drilling system and method provided by the present invention can monitor the continuous circulation drilling process in real time. The operation of connecting the main side circulation pipeline to the circulation sub and the opening and closing of all valves in the diversion manifold system are all operated by the control cabinet. The entire process does not require human intervention. The operator only needs to operate on the control cabinet to complete the entire process, which improves the safety of continuous circulation operation and saves labor and time costs. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the system connection of an automatic control continuous circulation drilling system according to an embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram of the system connection of an automatic control continuous circulation drilling system according to an embodiment of the present invention, which shows the connection of the main circulation pipeline;

[0025] Figure 3 This is a schematic diagram of the system connection of an automatic control continuous circulation drilling system according to an embodiment of the present invention, which shows the connection of the side circulation pipeline;

[0026] Figure 4 This is a schematic diagram of the structure of the diversion manifold system according to an embodiment of the present invention;

[0027] Figure 5 This is a schematic diagram of the auxiliary connection device according to an embodiment of the present invention;

[0028] Figure 6 This is a schematic flowchart of an automatic control continuous circulation drilling method according to an embodiment of the present invention;

[0029] Figure 7 This is a flowchart illustrating the specific content of the automatic control continuous circulation drilling method according to an embodiment of the present invention. Detailed Implementation

[0030] To better understand the purpose, structure, and function of this invention, the following detailed description of an automatic control continuous circulation drilling system and method of this invention is provided in conjunction with the accompanying drawings.

[0031] Figure 1 The system connections of an automated control continuous circulation drilling system 100 according to an embodiment of the present invention are shown. Figure 2 The connection of the main circulation pipeline 3 of an automatic control continuous circulation drilling system 100 according to an embodiment of the present invention is shown. Figure 3 The connection of the side circulation line 4 of an automated controlled continuous circulation drilling system 100 according to an embodiment of the present invention is shown. Figures 1 to 3As shown, the automatic control continuous circulation drilling system 100 includes a circulation sub 1, drill pipe 2, main circulation pipeline 3, side circulation pipeline 4, diversion manifold system 5, replenishment pump 6, replenishment pipeline 7, mud pump 8, pressure relief pipeline 9, and mud pit 10. The diversion manifold system 5 is equipped with a main circulation channel 51, a side circulation channel 52, a replenishment channel 53, a pressure relief channel 54, and an emergency channel 55. The circulation sub 1 is connected to the drill pipe 2, and simultaneously, the circulation sub 1 is connected to the main circulation pipeline 3 and the side circulation pipeline 4. The main circulation channel 51... The main circulation outlet 511 is connected to the main circulation pipeline 3. The side circulation outlet 521 of the side circulation channel 52 is connected to the side circulation pipeline 4. The replenishment inlet 531 of the replenishment channel 53 is connected to the replenishment pipeline 7 and the replenishment pump 6. The mud inlet 551 on the diversion manifold system 5 is connected to the mud pump 8. The replenishment pump 6 and the mud pump 8 are connected to the mud tank 10. The pressure relief outlet 541 of the pressure relief channel 54 is connected to the pressure relief pipeline 9 and the mud tank 10 in sequence. The inlet of the emergency channel 55 is the mud inlet 551, and the outlet of the emergency channel 55 is the main circulation outlet 511.

[0032] In this application, the diversion manifold system 5 is composed of several interconnected pipes. The replenishment channel 53 is connected at both ends to the main circulation channel 51 and the side circulation channel 52, respectively. The pressure relief channel 54 includes a main pressure relief channel 54 connected to the main circulation channel 51 and a side pressure relief channel 54 connected to the side circulation channel 52. Both the main pressure relief channel 54 and the side pressure relief channel 54 are connected to a pressure relief outlet 541. The emergency channel 55 has a mud inlet 551 at its inlet and a main circulation outlet 511 at its outlet. Additionally, the emergency channel 55 is equipped with a mud filter 552, which is connected to both the main circulation channel 51 and the side circulation channel 52.

[0033] Please continue to refer to Figures 1 to 3 In some embodiments, the circulation manifold 1 may include a main valve (not shown in the figure) and a side valve (not shown in the figure). The main valve is connected to the main circulation line 3, and the side valve is connected to the side circulation line 4. The liquid pressure difference when the channel of the manifold system 5 is switched realizes the opening and closing of the main valve and the side valve in the circulation manifold 1.

[0034] Please refer to Figure 4 In some embodiments, the diversion manifold system 5 may include a control cabinet 56 and a diversion manifold, on which a main circulation channel 51, a side circulation channel 52, a replenishment channel 53, a pressure relief channel 54 and an emergency channel 55 are formed. An electric throttle valve 57 and an electric gate valve 58 are installed on the main circulation channel 51 and the side circulation channel 52, and an electric gate valve 58 is installed on the replenishment channel 53, the emergency channel 55 and the pressure relief channel 54.

[0035] In this application, the diversion manifold can be understood as consisting of several interconnected pipes. The diversion manifold includes the main circulation channel 51, the side circulation channel 52, the replenishment channel 53, the emergency channel 55, and the pressure relief channel 54 as described in this application. The electric throttle valve 57 is used to control the flow rate between the channels, and the electric gate valve 58 is used to control the on / off state between the channels.

[0036] In some embodiments, pressure sensors (not shown in the figure) are installed on the main circulation channel 51, the side circulation channel 52, the replenishment channel 53, the pressure relief channel 54, and the emergency channel 55. The control cabinet 56 is configured to receive data from the pressure sensors so as to issue commands to the electric throttle valve 57 and the electric gate valve 58 after the pressure conditions for opening or closing the gate are met, thereby performing control.

[0037] In this application, by setting up the control cabinet 56, the automatic switching between the main circulation channel 51 and the side circulation channel 52 in the continuous circulation technology can be realized without human intervention, thereby improving the safety of continuous circulation operation.

[0038] In some embodiments, the pressure condition for opening or closing the gate is set to ensure that the pressure sensor reading remains stable at a preset value.

[0039] In this application, the pressure condition for opening or closing the gate can be further understood as: the reading of the pressure sensor reaches a preset value and remains stable.

[0040] Please refer to Figure 5 In some embodiments, an auxiliary connection device 11 is also included, which is used to move the side circulation line 4 to the front of the circulation stub 1.

[0041] In this application, the side circulation pipeline 4 is connected to the side valve of the circulation sub-section 1 via an auxiliary connection device 11. In some preferred embodiments, the auxiliary connection device 11 may be a trolley, and the control cabinet 56 may control the trolley to deliver the side circulation pipeline 4 to the side valve of the circulation sub-section 1. Then, the connector of the side circulation pipeline 4 is connected to the side valve, and the connection is electrically controlled to lock, eliminating the need for manual locking of the connector.

[0042] In conjunction with the automatic control continuous circulation drilling system 100 described above, the automatic control continuous circulation drilling method 200 of the system 100 will now be further explained:

[0043] Figure 6 A flowchart of an automatic control continuous circulation drilling method 200 according to an embodiment of the present invention is shown. Figure 7 The specific details of an automated control continuous circulation drilling method 200 according to an embodiment of the present invention are shown. (In conjunction with...) Figure 6 and Figure 7As shown, the steps of the automatic control continuous circulation drilling method 200 include: main circulation, side circulation fluid replenishment, switching from main circulation to side circulation, main circulation depressurization, side circulation, main circulation fluid replenishment, switching from side circulation to main circulation, side circulation depressurization, and main circulation. Specifically:

[0044] Main circulation: Before the drill pipe 2 is lowered into the ground, the mud pump 8 pumps the drilling fluid into the manifold system 5, and opens the electric gate valve 58 and electric throttle valve 57 of the main circulation channel 51 of the manifold system 5. The drilling fluid completes the drilling fluid circulation through the main circulation pipeline 3 and the drilling begins.

[0045] Side circulation fluid replenishment: After the drill pipe 2 is lowered into the ground, before connecting the column, the outlet of the side circulation pipeline 4 is connected to the side valve of the circulation subsection 1 above the drill pipe 2. The electric gate valve 58 of the fluid replenishment channel 53 of the diversion manifold is opened, and the fluid replenishment pump 6 replenishes the side circulation pipeline 4 through the fluid replenishment pipeline 7 to the predetermined pressure value. Then the electric gate valve 58 of the fluid replenishment channel 53 is closed.

[0046] Main circulation to side circulation: Control cabinet 56 issues a command, the electric gate valve 58 of the side circulation channel 52 opens, the electric throttle valve 57 gradually opens, the electric throttle valve 57 of the main circulation channel 51 gradually closes, and after the drilling fluid pressure stabilizes, the electric gate valve 58 of the main circulation channel 51 closes.

[0047] Furthermore, when the main circulation is switched to the side circulation, the electric throttle valve 57 of the main circulation channel 51 of the manifold gradually closes, the liquid pressure in the main circulation line 3 decreases, the electric throttle valve 57 of the side circulation channel 52 gradually increases, the liquid pressure in the side circulation line 4 increases, and the main valve in the circulation sub 1 closes and the side valve opens due to the pressure difference, so that the drilling fluid circulates through the side circulation channel 52 of the circulation sub 1.

[0048] Main circulation depressurization: Open the electric gate valve 58 on the depressurization channel 54 connected to the main circulation channel 51. The drilling fluid in the main circulation returns to the mud pit 10 through the depressurization pipeline 9, and the pressure drops to the minimum. Then close the electric gate valve 58 on the depressurization channel 54 connected to the main circulation channel 51 and disconnect the main circulation pipeline 3.

[0049] Side circulation: Start by connecting the standpipe, and the drilling fluid will circulate through side circulation line 4.

[0050] Main circulation replenishment: After the column is connected, the main circulation pipeline 3 is connected. The control cabinet 56 issues a command to open the electric gate valve 58 of the replenishment channel 53 of the diversion manifold to replenish the main circulation pipeline 3 to the predetermined pressure value, and then closes the electric gate valve 58 of the replenishment channel 53.

[0051] Side circulation to main circulation: Open the electric gate valve 58 of the main circulation channel 51, gradually open the electric throttle valve 57 of the main circulation channel 51 to the maximum, gradually close the electric throttle valve 57 of the side circulation channel 52 to the minimum, and after the drilling fluid pressure stabilizes, close the electric gate valve 58 of the side circulation channel 52.

[0052] Furthermore, when the side circulation switches to the main circulation, the pressure in the side circulation pipeline 4 decreases, while the pressure in the main circulation pipeline 3 increases. Due to the pressure difference, the main valve in the circulation section 1 will open and the side valve will close. The main circulation channel 51 in the circulation section 1 will close, while the side circulation channel 52 will open.

[0053] Side circulation pressure relief: Open the electric gate valve 58 on the pressure relief channel 54 connected to the side circulation channel 52. The side circulation drilling fluid returns to the mud pit 10 through the pressure relief pipeline 9. The pressure drops to the minimum. Close the electric gate valve 58 on the pressure relief channel 54 connected to the side circulation channel 52 and disconnect the side circulation pipeline 4.

[0054] Main circulation: The drilling fluid circulates through the main circulation pipeline 3 and continues drilling operations, repeating the above operations.

[0055] In summary, according to the automatic control continuous circulation drilling system 100 and method 200 of the present invention, the control cabinet 56 can receive data from each circulation channel through pressure sensors, monitor the continuous circulation drilling process in real time, and the operation of connecting the main side circulation pipeline 4 to the circulation sub 1 and the opening and closing of all valves in the diversion manifold system 5 are all operated by issuing commands from the control cabinet 56. The entire process does not require human intervention, and the operator only needs to operate on the control cabinet 56 to complete the entire process flow, which improves the safety of continuous circulation operation and saves labor and time costs.

[0056] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application should have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0057] 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. An automatically controlled continuous circulation drilling system, characterized by, The circulating short section, the drill pipe, the main circulating pipeline, the side circulating pipeline, the manifold system, the liquid supplement pump, the liquid supplement pipeline, the mud pump, the pressure relief pipeline and the mud pit are included. The main circulating channel, the side circulating channel, the liquid supplement channel, the pressure relief channel and the emergency channel are arranged in the manifold system, wherein the circulating short section is connected with the drill pipe, and the circulating short section is connected with the main circulating pipeline and the side circulating pipeline; the main circulating outlet of the main circulating channel is connected with the main circulating pipeline, the side circulating outlet of the side circulating channel is connected with the side circulating pipeline, the liquid supplement inlet of the liquid supplement channel is connected with the liquid supplement pipeline and the liquid supplement pump, the mud inlet of the manifold system is connected with the mud pump, the liquid supplement pump and the mud pump are connected with the mud pit, the pressure relief outlet of the pressure relief channel is connected with the pressure relief pipeline and the mud pit in sequence, the inlet of the emergency channel is the mud inlet, and the outlet of the emergency channel is the main circulating outlet.

2. The automatically controlled continuous circulation drilling system of claim 1, wherein, The main valve and the side valve are arranged in the circulating short section, the main valve is connected with the main circulating pipeline, the side valve is connected with the side circulating pipeline, and the opening and closing of the main valve and the side valve in the circulating short section are realized by the liquid pressure difference when the channel switching of the manifold system is performed.

3. The automatically controlled continuous circulation drilling system of claim 2, wherein, The manifold system includes a control cabinet and a manifold, the main circulating channel, the side circulating channel, the liquid supplement channel, the pressure relief channel and the emergency channel are arranged in the manifold, the electric throttle valve and the electric gate valve are arranged on the main circulating channel and the side circulating channel, and the electric gate valve is arranged on the liquid supplement channel, the emergency channel and the pressure relief channel.

4. The automatically controlled continuous circulation drilling system of claim 3, wherein, The pressure sensor is arranged on the main circulating channel, the side circulating channel, the liquid supplement channel, the pressure relief channel and the emergency channel, the control cabinet is arranged to receive the data of the pressure sensor, and the electric throttle valve and the electric gate valve are instructed to be controlled after the pressure condition of opening or closing is met.

5. The automatically controlled continuous circulation drilling system of claim 4, wherein, The pressure condition of opening or closing is set as the reading of the pressure sensor being stably kept at a preset value.

6. The automatically controlled continuous circulation drilling system of any of claims 1-5, wherein, The auxiliary connecting device is further arranged to move the side circulating pipeline to the front of the circulating short section.

7. An automatically controlled continuous circulation drilling method applied to the automatically controlled continuous circulation drilling system according to claims 1 to 6, characterized in that, The method includes the steps of main circulation, side circulation liquid supplement, main circulation to side circulation, side circulation, side circulation to main circulation, main circulation, wherein: The main circulation: before the drill pipe is lowered, the mud pump pumps the drilling fluid into the manifold system, the electric gate valve and the electric throttle valve of the main circulating channel of the manifold system are opened, the drilling fluid is circulated through the main circulating pipeline, and the drill pipe is lowered; The side circulation liquid supplement: after the drill pipe is lowered, before the column is connected, the outlet of the side circulating pipeline is connected with the side valve of the circulating short section above the drill pipe, the electric gate valve of the liquid supplement channel of the manifold is opened, the liquid supplement pump supplements the liquid in the side circulating pipeline through the liquid supplement pipeline, the liquid supplement is performed to a predetermined pressure value, and then the electric gate valve of the liquid supplement channel is closed; The side circulation to main circulation: after the column is connected, the outlet of the side circulating pipeline is connected with the main circulating pipeline, the electric gate valve of the main circulating channel of the manifold is opened, the electric gate valve of the side circulating channel of the manifold is closed, the electric throttle valve of the main circulating channel is opened, the electric throttle valve of the side circulating channel is closed, and the electric gate valve of the main circulating channel is closed. The main circulation turns to the side circulation: the control cabinet sends out an instruction, the electric gate valve of the side circulation channel is opened, the electric throttle valve is gradually opened, the electric throttle valve of the main circulation channel is gradually closed, and the electric gate valve of the main circulation channel is closed after the drilling fluid pressure is stabilized; The side circulation: the standpipe is connected, and the drilling fluid is circulated through the side circulation pipeline; The main circulation liquid supplement: after the standpipe is connected, the main circulation pipeline is connected, the control cabinet sends out an instruction, the electric gate valve of the liquid supplement channel of the flow divider manifold is opened, the main circulation pipeline is supplemented with liquid to a predetermined pressure value, and then the electric gate valve of the liquid supplement channel is closed; The side circulation turns to the main circulation: the electric gate valve of the main circulation channel is opened, the electric throttle valve of the main circulation channel is gradually opened to the maximum, the electric throttle valve of the side circulation channel is gradually closed to the minimum, and the electric gate valve of the side circulation channel is closed after the drilling fluid pressure is stabilized; The main circulation: the drilling fluid is circulated through the main circulation pipeline, the drilling operation is continued, and the above operations are repeated.

8. The continuously-cycling, automatically-controlled drilling method of claim 7, wherein, The main circulation turns to the side circulation further comprises: When the main circulation is switched to the side circulation, the electric throttle valve of the main circulation channel of the flow divider manifold is gradually closed, the liquid pressure in the main circulation pipeline is reduced, the electric throttle valve of the side circulation channel is gradually increased, the liquid pressure in the side circulation pipeline is increased, the main valve is closed and the side valve is opened in the circulation sub due to the pressure difference, and the drilling fluid is circulated through the side circulation channel of the circulation sub.

9. The continuously-cycling, automatically-controlled drilling method of claim 8, wherein, The side circulation turns to the main circulation further comprises: When the side circulation turns to the main circulation, the pressure in the side circulation pipeline is reduced, the pressure in the main circulation pipeline is increased, the main valve is opened and the side valve is closed in the circulation sub due to the pressure difference, the main circulation channel 51 in the circulation sub is closed, and the side circulation channel is opened.

10. The continuously-cycling, automatically-controlled drilling method of claim 9, wherein, The automatic control continuous circulation drilling method further comprises: The main circulation pressure relief: the electric gate valve on the pressure relief channel connected with the main circulation channel is opened, the drilling fluid in the main circulation is returned to the mud pit through the pressure relief pipeline, the pressure is lowered to the minimum, and then the electric gate valve on the pressure relief channel connected with the main circulation channel is closed, and the main circulation pipeline is removed; The side circulation pressure relief: the electric gate valve on the pressure relief channel connected with the side circulation channel is opened, the side circulation drilling fluid is returned to the mud pit through the pressure relief pipeline, the pressure is lowered to the minimum, and the electric gate valve on the pressure relief channel connected with the side circulation channel is closed, and the side circulation pipeline is removed.

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