Automatic control method for preventing eccentric wear of sucker rod in horizontal well oil production

Abstract

The present application relates to a method for automatically regulating the deviation wear of the sucker rod in the horizontal well oil production, observing the load sensor after starting, at this time the load value is the maximum; the sucker rod rotates at a set speed or does not rotate while being lowered; during the lowering process, when the load weight starts to decrease, it means that the bottom device of the equipment touches the bottom of the sucker rod; the oil pumping is carried out under the current working parameters, and the real-time value of the torque is monitored; if the torque exceeds the set early warning torque, the optimization operation is executed, and the change of the torque after the optimization operation is judged; after the optimization operation, if the torque is lower than the set early warning torque, the normal mining is continued; if the torque still exceeds the early warning value after the speed and / or the range of lifting the sucker rod are exceeded, the sucker rod is lifted to the preset position, and the initial step is repeated; thereby effectively regulating the torque to make it in the best state, reducing or even avoiding the occurrence of deviation wear, greatly improving the service life of the sucker rod, and having good practicability.

Description

Technical Field

[0001] This invention relates to the field of oil production equipment technology, and in particular to an automatic control method for preventing eccentric wear of sucker rods in horizontal well oil production. Background Technology

[0002] In the field of oil extraction, low-permeability reservoirs and heavy oil extraction are the main development targets of major oilfields. Due to the small contact area between vertical wells and oil-bearing formations, steam flooding is not very effective. Therefore, in practical applications, a combination of steam flooding and horizontal wells is often used. Horizontal wells have become an effective means of realizing the industrial value of low-permeability and heavy oil fields, increasing production by 3-12 times that of vertical wells. The number of horizontal wells is increasing significantly year by year, which is an inevitable trend for the future.

[0003] Horizontal wells are special wells that maintain a certain length of horizontal section in the target formation. During oil production in horizontal wells, factors such as prolonged production time and changes in dynamic fluid level can easily cause uneven wear between the sucker rod and the tubing, especially at the corners of the horizontal well where uneven wear occurs due to the contact and contact between the sucker rod and the tubing. Uneven wear not only affects the normal progress of oil production, but in severe cases, it can lead to the tubing being worn through or the sucker rod breaking. Summary of the Invention

[0004] In response to the shortcomings of the existing production technologies, the applicant provides a reasonably structured automatic control method for preventing uneven wear of sucker rods in horizontal well oil production. By adjusting the weight distribution and rotation speed in a timely manner, the torque is effectively controlled to keep the sucker rod in its optimal state, reducing or even avoiding uneven wear, greatly improving the service life of the sucker rod, and demonstrating good practicality.

[0005] The technical solution adopted in this invention is as follows:

[0006] An automatic control method for preventing eccentric wear of sucker rods in horizontal well oil production includes the following steps:

[0007] Step 1: Place the sucker rod at its highest position and use the load sensor to record and report the current load weight M0, which is the maximum value;

[0008] Step 2: Lower the sucker rod until the load weight drops to M1, and set the extraction position at the load weight M1, where M1 is less than or equal to M0;

[0009] Step 3: Set the warning torque and monitor the real-time torque value;

[0010] Step 4: If the torque exceeds the warning torque, perform optimization operation: reduce the speed and / or raise the sucker rod, and then judge the torque change after the optimization operation;

[0011] Step 5: After N optimization operations, if the torque is lower than the set warning torque, continue normal mining; if the torque still exceeds the warning torque, raise the sucker rod to the preset position; repeat steps 1-5.

[0012] As a further improvement to the above technical solution:

[0013] One end of the sucker rod extends upwards out of the ground and is equipped with a load sensor, a lifting mechanism, and a rotating mechanism. The load sensor provides real-time feedback on the current load weight, the lifting mechanism drives the upper part of the sucker rod to move up and down, and the rotating mechanism drives the sucker rod to rotate and deliver oil upwards. The lower part of the sucker rod extends into the horizontal section of the sucker tube and is equipped with a positioning mechanism and a stator-rotor assembly.

[0014] During the extraction process, the rotation speed is reduced to cope with the continuous increase in torque. If the rotation speed is reduced beyond the lower limit of the threshold range, the sucker rod is raised. If the rotation speed is still within the preset threshold range, normal extraction continues while the torque is monitored.

[0015] In the second step, the sucker rod can be lowered by rotation, with a rotation speed range of 0.2-0.9 times the operating speed. Alternatively, the sucker rod can be lowered by non-rotation.

[0016] When monitoring the torque value, set the working torque T0, which is the minimum torque value. If the torque decreases below the working torque T0, increase the rotation speed to increase the mining output.

[0017] In steps four and five, if the torque continues to increase, reduce the rotational speed. If the torque continues to increase after reducing the rotational speed, continue to reduce the rotational speed. If the torque continues to increase after reducing the rotational speed n times, then raise the sucker rod. n is greater than or equal to one.

[0018] The outer wall of the sucker rod is configured as a spiral structure along the axial direction.

[0019] The beneficial effects of this invention are as follows:

[0020] This invention is ingeniously conceived. By raising the sucker rod to its heaviest load position and lowering it to observe the change in load weight, the extraction location is determined based on the relationship between the load weight change and the real-time torque and warning torque. During normal oil production, in response to the continuous increase in torque, the torque is effectively controlled to maintain its optimal state by adjusting the rotation speed and / or raising the sucker rod, reducing or even avoiding uneven wear, and greatly extending the service life of the sucker rod and tubing. It is highly practical.

[0021] The present invention also includes the following advantages:

[0022] The method for adjusting the anti-wear torque of the sucker rod in this invention is also applicable to adjustments during gas extraction.

[0023] If the preset torque reduction is not achieved after multiple attempts to reduce the speed and / or raise the sucker rod, the sucker rod should be raised to facilitate timely and comprehensive inspection by the operator and to eliminate interference from other factors affecting oil production.

[0024] For different horizontal wells, torque limits and speed limits can be set according to the actual mining conditions. If either torque or speed exceeds the set value, measures can be taken in a timely manner to reduce or even avoid potential adverse situations, so that operators can be informed in a timely manner and conduct a comprehensive inspection. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the process of the present invention.

[0026] Figure 2 This is a schematic diagram of the oil production screw pump device of the present invention.

[0027] The components include: 1. Rotation mechanism; 2. Lifting mechanism; 3. Load sensor; 4. Sucker rod; 5. Positioning mechanism; 6. Pump; 10. Ground; 20. Sucker pipe. Detailed Implementation

[0028] The specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0029] like Figure 2 As shown, this is a schematic diagram of the oil production screw pump unit in operation. One end of the sucker rod 4 extends upwards out of the ground 10 and is equipped with a load sensor 3, a lifting mechanism 2, and a rotating mechanism 1. The load sensor 3 provides real-time feedback on the current load weight. The lifting mechanism 2 drives the upper part of the sucker rod 4 to move up and down, and the rotating mechanism 1 drives the sucker rod 4 to rotate and pump oil upwards. The lower part of the sucker rod 4 extends into the horizontal section of the sucker tubing 20 and is equipped with a positioning mechanism 5 and a stator-rotor assembly 6. The sucker tubing 20 is relatively fixed in the oil well tubing.

[0030] During oil extraction, the sucker rod 4 will be subjected to the buoyancy of the oil in the tubing 20. The dynamic fluid level of the oil fluctuates and changes under the influence of various factors, such as the progress of extraction, temperature, and tides. The buoyancy exerted by the oil on the sucker rod 4 will change with the fluctuation of the dynamic fluid level. Considering the weight of the sucker rod 4 and the amount of oil inside, and the fact that the tail end of the sucker rod 4 is confined within the tubing 20 by the positioning mechanism 5, the load weight monitored and fed back by the load sensor 3 will change as the buoyancy of the sucker rod 4 changes, or as the length and tautness of the sucker rod 4 within the tubing 20 changes. Especially when the outer wall of the sucker rod 4 contacts and wears against the inner wall of the tubing 20, the load weight monitored and fed back by the load sensor 3 will be very large. Figure 2 The double-dotted line in the middle indicates the case of uneven wear; at the same time, the torque value changes with the load weight.

[0031] This invention relates to an automatic control method for preventing eccentric wear of sucker rods in horizontal well oil production. After startup, the sucker rod is raised until the load sensor reports the current load to the maximum value M0. The sucker rod 4 rotates at a set speed and is lowered simultaneously. During the lowering process, when the load weight begins to decrease, the load weight at the lowest point is set to M1. This means that the control mechanism 5 has reached the bottom and reached the working position, but it is not yet optimal. When the load weight is less than or equal to M0, continue lowering the rod. The torque begins to decrease, reaching an inflection point. Set the torque at the inflection point as the working torque T0. At this point, the load weight begins to decrease, and set the load weight at the inflection point as the working weight M2. Pump oil under the current working parameters, monitoring the real-time torque value. If the torque continues to increase, reduce the rotation speed and determine the change in torque after the rotation speed decreases. If the torque begins to decrease after the rotation speed decreases, continue normal extraction. If the torque continues to increase after multiple reductions in rotation speed, raise the sucker rod to the load weight M0. If the torque continues to increase, raise the sucker rod to the maximum load value M0. Repeat the initial steps. By adjusting the rotation speed in a timely manner, the torque is effectively controlled to maintain its optimal state, reducing or even avoiding uneven wear, greatly improving the service life of the sucker rod, and demonstrating good practicality.

[0032] like Figure 1 As shown in this embodiment, the automatic control method for preventing eccentric wear of sucker rod in horizontal well oil production includes the following steps:

[0033] Step 1: Place the sucker rod 4 at its highest position and use the load sensor 3 to record and report the current load weight M0, which is the maximum value;

[0034] Step 2: Lower the sucker rod 4 until the load weight drops to M1, and set the mining position at the load weight M1, where M1 is less than or equal to M0. In actual situations, after the control mechanism 5 touches the bottom, the sucker rod 4 can be lowered further to make the load weight reach the minimum. At this time, the load weight is M2. The suitable mining load weight M1 is between the maximum load weight M0 and the minimum load weight M2.

[0035] Step 3: Set the warning torque and monitor the real-time torque value. When the real-time torque value is less than the preload torque and the load weight is M1, it is the oil extraction point.

[0036] Step 4: If the torque exceeds the warning torque, perform optimization operation: reduce the speed and / or raise the sucker rod, and then judge the torque change after the optimization operation;

[0037] Step 5: After N optimization operations, if the torque is lower than the set warning torque, continue normal mining; if the torque still exceeds the warning torque, raise the sucker rod to the preset position; repeat steps 1-5.

[0038] During the extraction process, the rotation speed is reduced to cope with the continuous increase in torque. If the rotation speed is reduced beyond the lower limit of the threshold range, the sucker rod is raised. If the rotation speed is still within the preset threshold range, normal extraction continues while the torque is monitored.

[0039] In the second step, the sucker rod 4 can be lowered by rotation, with a rotation speed range of 0.2-0.9 times the operating speed. Alternatively, the sucker rod 4 can be lowered by non-rotation.

[0040] When monitoring the torque value, set the working torque T0, which is the minimum torque value. If the torque decreases below the working torque T0, increase the rotation speed to increase the production rate, thereby effectively balancing the adjustment of the torque at the optimal state with the oil production rate.

[0041] The outer wall of the sucker rod 4 is designed with a spiral structure along the axial direction.

[0042] In this embodiment, the torque inflection point is obtained by raising the sucker rod 4 to the position with the heaviest load and lowering the sucker rod 4 to achieve weight distribution; during normal oil production, in response to the continuous increase in torque, the torque is effectively controlled to keep it in the optimal state by timely reducing the rotation speed.

[0043] If the preset torque reduction is not achieved after multiple attempts to reduce the speed as the torque continues to increase, the sucker rod is raised to the maximum load value. This allows operators to conduct a timely and comprehensive inspection and eliminate interference from other factors affecting oil production.

[0044] For example, when the working torque is 300 rpm, the warning torque can be set to 600 rpm. When the torque is above the upper limit, the speed will not be adjusted, but the sucker rod will be lifted directly. Of course, the warning torque in this embodiment can be preset according to the actual horizontal well production situation, such as a certain value greater than the working torque as the upper limit, and can be adjusted according to the actual situation.

[0045] During the extraction process, the rotation speed is reduced to cope with the continuous increase in torque. If the rotation speed is reduced beyond the lower limit of the threshold range, the sucker rod is directly raised. If the rotation speed is still within the preset threshold range, normal extraction continues while the torque is monitored.

[0046] For different horizontal wells, torque limits and speed limits can be set according to the actual mining conditions. If either torque or speed exceeds the set value, measures can be taken in a timely manner to reduce or even avoid potential adverse situations, so that operators can be informed in a timely manner and conduct a comprehensive inspection.

[0047] In the second step, sucker rod 4 can be lowered by rotation, with a rotation speed range of 0.2-0.9 times the operating speed. Alternatively, sucker rod 4 can be lowered without rotation. For example, if the initial speed setting is 100 rpm, the minimum speed can be set to 70 rpm. During the adjustment of the speed as the torque increases, if the speed has already been adjusted to the minimum value of 70 rpm or even lower, the sucker rod needs to be raised regardless of the current torque state. This is especially true if the torque continues to increase after the speed has reached the minimum value, which is highly likely to indicate a malfunction or problem, such as a rapid drop in the dynamic fluid level, sand production, or excessively heavy oil. Therefore, it is necessary to raise the sucker rod first and then repeat steps one through five.

[0048] During normal oil production, torque will fluctuate to some extent due to external factors. When the torque value continues to increase, it is highly likely that uneven wear, malfunction, or other problems have occurred. By reducing the rotational speed, the torque can be adjusted to reduce the possible uneven wear. On the other hand, by repeatedly reducing the rotational speed and combining it with the actual monitoring of the torque value, it is possible to determine whether there is a malfunction other than uneven wear.

[0049] In steps four and five, if the torque continues to increase, reduce the rotational speed. If the torque continues to increase after reducing the rotational speed, continue to reduce the rotational speed. If the torque continues to increase after reducing the rotational speed n times, then raise the sucker rod. n is greater than or equal to 1.

[0050] In this embodiment, the setting of n is closely related to the continuous increase of torque and the matching decrease of speed. If the continuous increase of torque is not affected after the speed is reduced multiple times, it can be determined that other faults such as uneven wear have occurred in this case.

[0051] The specific setting of n can be set or adjusted according to the actual mining situation, mainly to prevent the abnormal and continuous increase of surface torque.

[0052] For example, if the initial torque is set to 500N, the initial speed to 100r / min, the warning torque to 800N, the lower limit of the speed to 70r / min, and the upper limit of the speed to 150r / min; when the torque value is maintained at around 500N during operation, normal mining will proceed; when the torque value continues to increase, for example, to above 550N, the speed will begin to decrease.

[0053] For the first adjustment, reduce the rotation speed to 90 r / min. If the torque value drops to around 500 N, the equipment can operate normally. If the torque continues to increase to around 600 N, and the torque value has not yet reached the warning torque, and the rotation speed is within the set range, then continue to reduce the rotation speed. If the torque increases to above 800 N at this time, then raise the sucker rod to restart.

[0054] The second adjustment involves reducing the rotational speed to 80 r / min. If the torque value decreases to around 500 N, the equipment can operate normally. If the torque continues to increase to around 700 N, and the torque value has not reached the warning torque, and the rotational speed is within the set range, the rotational speed should be further reduced. If the torque increases to above 800 N at this point, the sucker rod should be raised to restart the operation.

[0055] The third adjustment involves reducing the rotational speed to 70 r / min. If the torque value decreases to around 500 N, the equipment can operate normally. If the torque continues to increase to around 750 N, and the torque value has not reached the warning torque, and the rotational speed is within the set range, the rotational speed should be further reduced. If the torque increases to above 800 N at this point, the sucker rod should be raised to restart.

[0056] For the fourth adjustment, reduce the speed to below 70 r / min. Since this is below the lower limit of the speed, raise the sucker rod and repeat steps two through six.

[0057] If n is set to three times, and the torque value continues to increase after the third adjustment, the sucker rod will be raised after the third adjustment.

[0058] The automatic control of this invention can automatically perform control operations through the analysis of collected data by the intelligent control system. The limiting values ​​involved, such as warning torque, upper limit of speed, lower limit of speed, and speed adjustment range, can be preset by the operator according to the actual situation of the current oil extraction.

[0059] The outer wall of the sucker rod 4 is designed with a spiral structure along the axial direction. When the sucker rod 4 is close to or even in contact with the inner wall of the sucker tube 20, the edge of the spiral structure interacts with the inner wall of the sucker tube 20, thereby effectively reducing the contact and interaction area and reducing the actual area of ​​uneven wear in case of uneven wear.

[0060] The method for adjusting the anti-wear torque of the sucker rod in this invention is also applicable to adjustments during gas extraction.

[0061] This invention effectively regulates torque to its optimal state through timely adjustment of rotation speed, reducing or even avoiding uneven wear, greatly extending the service life of the sucker rod, and demonstrating good practicality.

[0062] This invention relates to an automatic control method for preventing eccentric wear of sucker rods in horizontal well oil production. Upon startup, the load sensor is monitored, and the load value is at its maximum. The sucker rod is lowered simultaneously, rotating at a set speed or without rotation. During lowering, as the load weight begins to decrease, it indicates that the control adjustment device has reached the bottom. Oil is pumped under the current operating parameters, and the real-time torque value is monitored. If the torque exceeds the set warning torque, an optimization operation is performed (reducing the speed and / or raising the sucker rod), and the change in torque after the optimization operation is assessed. After the optimization operation, if the torque is lower than the set warning torque, normal production continues. If the torque still exceeds the warning value after exceeding the range of speed and / or raising the sucker rod, it is raised to a preset position, and the initial steps are repeated. This effectively controls the torque to maintain its optimal state, reducing or even avoiding eccentric wear, greatly extending the sucker rod's service life, and demonstrating good practicality.

[0063] The above description is an explanation of the present invention and not a limitation thereof. The scope of the present invention is defined by the claims. Within the scope of protection of the present invention, any form of modification may be made.

Claims

1. An automatic control method for preventing eccentric wear of sucker rods in horizontal well oil production, characterized in that: Includes the following steps: Step 1: The sucker rod (4) is located at the maximum load weight M0 recorded by the load sensor (3); Step 2: Lower the sucker rod (4) until the load weight drops to M1, and set the extraction position at the load weight M1, where M1 is less than or equal to M0; Step 3: Set the warning torque and monitor the real-time torque value; Step 4: If the torque exceeds the warning torque, perform optimization operation: reduce the speed and / or raise the sucker rod, and then judge the torque change after the optimization operation; Step 5: After N optimization operations, if the torque is lower than the set warning torque, then continue normal mining; If the torque still exceeds the warning torque, raise the sucker rod to the first step position; repeat steps two through five. One end of the sucker rod (4) extends upwards out of the ground (10) and is equipped with a load sensor (3), a lifting mechanism (2), and a rotating mechanism (1). The load sensor (3) provides real-time feedback on the current load weight. The lifting mechanism (2) drives the upper part of the sucker rod (4) to move up and down. The rotating mechanism (1) drives the sucker rod (4) to rotate and pump oil upwards. The lower part of the sucker rod (4) extends into the horizontal section of the sucker pipe (20) and is equipped with a positioning mechanism (5) and a stator-rotor assembly (6).

2. The automatic control method for preventing eccentric wear of sucker rod in horizontal well oil production as described in claim 1, characterized in that: During the extraction process, the rotation speed is reduced to cope with the continuous increase in torque. If the rotation speed is reduced beyond the lower limit of the threshold range, the sucker rod is raised. If the rotation speed is still within the preset threshold range, normal extraction continues while the torque is monitored.

3. The automatic control method for preventing eccentric wear of sucker rod in horizontal well oil production as described in claim 2, characterized in that: In the second step, the sucker rod (4) can be lowered by rotation, with a rotation speed range of 0.2-0.9 times the working speed. The sucker rod (4) can also be lowered by non-rotation.

4. The automatic control method for preventing eccentric wear of sucker rod in horizontal well oil production as described in claim 1, characterized in that: When monitoring the torque value, set the working torque T0, which is the minimum torque value. If the torque decreases below the working torque T0, increase the rotation speed to increase the mining output.

5. The automatic control method for preventing eccentric wear of sucker rod in horizontal well oil production as described in claim 1, characterized in that: In steps four and five, if the torque continues to increase, reduce the rotational speed. If the torque continues to increase after reducing the rotational speed, continue to reduce the rotational speed. If the torque continues to increase after reducing the rotational speed n times, then raise the sucker rod. n is greater than or equal to one.

6. The automatic control method for preventing eccentric wear of sucker rod in horizontal well oil production as described in claim 1, characterized in that: The outer wall of the sucker rod (4) is configured as a spiral structure along the axial direction.

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