A protector and a screw pump comprising the same

Abstract

This invention relates to a protector and a screw pump incorporating the protector, used in the oil extraction field. The protector includes a transmission assembly and an elastic assembly. The transmission assembly, using a threaded connection, converts torque into relative displacement along the axial direction of the protector. The elastic assembly limits the displacement of the transmission assembly by providing elastic force along the axial direction of the protector. The cooperation of the transmission assembly and the elastic assembly ensures that the torque value experienced by the protector is within a set threshold. The protector of this invention can adjust the stator-rotor clearance of the screw pump in real time according to the set torque threshold, thereby improving the oil extraction efficiency of the screw pump.

Description

Technical Field

[0001] This invention relates to the field of screw pump technology, and in particular to a protector and a screw pump including the protector. Background Technology

[0002] In current oilfield screw pump systems, linear screw pumps are commonly used. These systems are characterized by fixed coaxiality and clearance between the stator and rotor, and their design does not require dynamic adjustment of the clearance. However, in tapered screw pumps, the clearance between the tapered stator and the tapered rotor needs precise control.

[0003] Current technology for adjusting the gap between the conical stator and rotor requires active control of the rotor's lifting or lowering. Operators typically determine the need for adjustment and the specific adjustment amount based on torque and pressure values. This process is not only time-consuming and labor-intensive, requiring frequent checks, but also demands a certain level of expertise from the operators, resulting in high labor costs. Furthermore, in special circumstances such as sand jams, if operators fail to intervene promptly, the screw pump will seize and stop. Restarting the screw pump is extremely time-consuming and labor-intensive, impacting oil extraction efficiency.

[0004] Therefore, we propose a protector and a screw pump incorporating the protector. Summary of the Invention

[0005] In view of the shortcomings of the prior art mentioned above, the applicant provides a protector and a screw pump including the protector, which can adaptively adjust the stator-rotor clearance.

[0006] The technical solution adopted in this invention is as follows:

[0007] A protector includes a transmission component and an elastic component. The transmission component converts torque into relative displacement along the axial direction of the protector by means of a threaded connection. The elastic component limits the displacement of the transmission component by providing elastic force along the axial direction of the protector. The cooperation between the transmission component and the elastic component ensures that the torque value of the protector 1 is within a set threshold.

[0008] The further technical solution includes a transmission assembly comprising a transmission screw 101 and a connecting nut 102, wherein the transmission screw 101 and the connecting nut 102 are connected by a transmission thread.

[0009] The further technical solution includes that the elastic component includes an elastic element 103 and a connecting sleeve 104, wherein the elastic element 103 is disposed inside the connecting sleeve 104 and can elastically extend and retract along the axial direction of the connecting sleeve 104.

[0010] The further technical solution includes an elastic component 103, which is disposed inside the connecting nut 102 and sleeved outside the smooth rod of the transmission screw 101. The two ends of the elastic component 103 abut against the stepped hole and the internal transmission thread 1021 of the connecting nut 102, and can elastically expand and contract within the smooth hole 1023 at one end of the connecting nut 102 along the axial direction of the connecting nut 102.

[0011] Further technical solutions include that the elastic component also includes an adapter 106, wherein an external thread 1061 at one end of the adapter 106 is used to thread it to the internal thread 1022 at one end of the connecting nut 102.

[0012] Further technical solutions include that the elastic component also includes a push rod 105, which is located inside the connecting sleeve 104, with one end abutting against the elastic element 103 and the other end abutting against the transmission screw 101.

[0013] The further technical solution includes that the push rod 105 includes a cylindrical rod portion 1051 and a head 1052, and the cross-sectional diameter of the head 1052 is larger than the cross-sectional diameter of the rod portion 1051. The head 1052 abuts against the elastic element 103, and the rod portion 1051 abuts against the transmission screw 101. The connecting sleeve 104 is provided with a stepped hole that matches the shape of the push rod 105, which is used to axially limit the elastic element 103 and the push rod 105.

[0014] The further technical solution includes that the connecting sleeve 104 is provided with a through hole and includes at least one vent hole 1043, the vent hole 1043 is arranged radially and penetrates through the section of the through hole where the elastic member 103 is located and the outside of the connecting sleeve.

[0015] Further technical solutions include that the elastic component also includes an adapter 106 and a gasket 107. The external thread 1061 at one end of the adapter 106 is used to connect with the internal thread 1041 at one end of the connecting sleeve 104. The gasket 107 is located inside the connecting sleeve 104 and its two end faces abut against the adapter 106 and the elastic element 103, respectively.

[0016] The further technical solution includes that the connecting nut 102 has a through hole 2, and the through hole 2 has an internal thread 2 1022 and an internal transmission thread 1021. The internal thread 2 1022 is used to connect with the external thread 2 1042 at one end of the connecting sleeve 104, and the internal transmission thread 1021 is used to connect with the external transmission thread 1011 at one end of the transmission screw 101.

[0017] A screw pump includes the protector 1, a stator 2, a rotor 3, and a drive unit 4; the rotor 3 is located inside the stator 2, and the drive unit 4 achieves oil extraction by driving the rotor 3 to rotate; the protector 1 is located between the rotor 3 and the drive unit 4.

[0018] Further technical solutions include: one end of the protector 1 is connected to the rotor 3 via a transmission screw 101, and the other end of the protector 1 is connected to the drive unit 4 via an adapter 106. Alternatively, one end of the protector 1 is connected to the drive unit 4 via a transmission screw 101, and the other end of the protector 1 is connected to the rotor 3 via an adapter 106.

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

[0020] The protector of this invention can adjust the stator-rotor clearance of a screw pump in real time according to a set torque threshold, thereby improving the oil extraction efficiency of the screw pump. The transmission component in the protector uses a threaded connection to convert torque into relative displacement along the axial direction of the protector, while the elastic component limits the displacement of the transmission component by providing elastic force along the axial direction of the protector. When the elastic force and torque are balanced, the transmission screw in the transmission component can rotate synchronously with the connecting nut at a fixed axial position, so that the rotor rotates within the stator with an appropriate clearance, achieving efficient oil extraction.

[0021] The protector of this invention can achieve bidirectional adjustment. When sand gets stuck in the stator and rotor, the rotor torque increases, and the protector can lift the rotor to allow the sand to fall in time, preventing the screw pump from completely jamming and causing more serious equipment failure. It also avoids oil production losses during the screw pump shutdown and restart process. When the gap between the stator and rotor increases due to wear, the rotor torque decreases, and the protector can lower the rotor. The adaptive gap compensation effectively ensures pump efficiency and improves oil production efficiency.

[0022] The present invention can also be configured with multiple protectors according to actual conditions, thereby increasing the adjustment range of stator-rotor gap without changing the structure of the protectors. Attached Figure Description

[0023] Figure 1 This is a cross-sectional structural diagram of the protector in one embodiment of the present invention.

[0024] Figure 2 This is a schematic diagram of the transmission screw in one embodiment of the present invention.

[0025] Figure 3 This is a cross-sectional structural diagram of the connecting nut in one embodiment of the present invention.

[0026] Figure 4 (a) is a schematic diagram of the stacked combination of disc springs in one embodiment of the present invention.

[0027] Figure 4 (b) is a schematic diagram of the mating combination structure of the disc spring in one embodiment of the present invention.

[0028] Figure 4 (c) is a schematic diagram of a hybrid combination structure of a disc spring in one embodiment of the present invention.

[0029] Figure 5 This is a schematic diagram of the top rod structure in one embodiment of the present invention.

[0030] Figure 6 This is a schematic diagram of the connecting sleeve in one embodiment of the present invention.

[0031] Figure 7 This is a schematic diagram of the adapter structure in one embodiment of the present invention.

[0032] Figure 8 This is a cross-sectional structural diagram of a screw pump in one embodiment of the present invention.

[0033] Figure 9 This is a cross-sectional structural diagram of the protector in another embodiment of the present invention.

[0034] The components are as follows: 1. Protector; 101. Transmission screw; 1011. External transmission thread; 1012. External thread three; 102. Connecting nut; 1021. Internal transmission thread; 1022. Internal thread two; 103. Elastic element; 104. Connecting sleeve; 1041. Internal thread one; 1042. External thread two; 1043. Vent hole; 105. Top rod; 1051. Rod part; 1052. Head; 106. Adapter; 1061. External thread one; 1062. External thread four; 1063. Thick rod; 107. Washer; 2. Stator; 3. Rotor; 4. Drive unit; 5. Oil pipe fittings; 6. Eccentric rod. Detailed Implementation

[0035] The specific embodiments of this application are described below with reference to the accompanying drawings. Example 1

[0036] like Figure 1 As shown, this embodiment discloses a protector for use in the field of oil extraction. Its structure includes a transmission component and an elastic component. The transmission component uses a threaded connection to convert torque into relative displacement along the axial direction of the protector. The elastic component limits the displacement of the transmission component by providing elastic force along the axial direction of the protector. The cooperation between the transmission component and the elastic component ensures that the torque value received by the protector 1 is within a set threshold.

[0037] In this embodiment, the transmission assembly includes a transmission screw 101 and a connecting nut 102, and the transmission screw 101 and the connecting nut 102 are connected by a transmission thread.

[0038] Optionally, the drive thread may be a rectangular thread.

[0039] like Figure 2 As shown, the transmission screw 101 has an external transmission thread 1011 at one end and an external thread 1012 at the other end, with the middle part being a smooth rod.

[0040] like Figure 3 As shown, the connecting nut 102 has a through hole 2, and the through hole 2 has an internal thread 2 1022 and an internal transmission thread 1021. The internal thread 2 1022 is used to connect with the external thread 2 1042 at one end of the connecting sleeve 104, and the internal transmission thread 1021 is used to connect with the external transmission thread 1011 at one end of the transmission screw 101.

[0041] Optionally, the second internal thread 1022 is located at one end of the second through hole, and the other end of the second through hole is a smooth hole 1023. The diameter of the smooth hole 1023 is smaller than the maximum diameter of the internal transmission thread 1021, which is used to prevent the transmission screw 101 from disengaging from the connecting nut 102 during rotation.

[0042] In this embodiment, the elastic component includes an elastic element 103 and a connecting sleeve 104. The elastic element 103 is disposed inside the connecting sleeve 104 and can elastically extend and retract along the axial direction of the connecting sleeve 104.

[0043] Optionally, the elastic element 103 is a disc spring. Disc springs have strong load-bearing, buffering, and shock absorption capabilities, making them more suitable for screw pump applications.

[0044] Disc springs, when combined in different ways, will exhibit different forces and deformations, such as... Figure 4 As shown, Figure 4 (a) If the stacking method is adopted, the overall deformation of the elastic element 103 is the same as the deformation of a single disc spring, and the force on the elastic element 103 is the force on a single disc spring multiplied by the number of disc springs. Figure 4 (b) If the coupling method is adopted, the overall deformation of the elastic element 103 is the deformation of a single disc spring multiplied by the number of disc springs, and the force on the elastic element 103 as a whole is the same as the force on a single disc spring. Figure 4 (c) If a hybrid method is adopted, the overall deformation of the elastic element 103 is the deformation of a single disc spring multiplied by the number of disc springs in the pair, and the overall force of the elastic element 103 is the force of a single disc spring multiplied by the number of stacked disc springs in the group.

[0045] The resilient assembly also includes a push rod 105, such as Figure 1 As shown, the push rod 105 is located inside the connecting sleeve 104, with one end abutting against the elastic element 103 and the other end abutting against the transmission screw 101.

[0046] like Figure 5As shown, the push rod 105 includes a cylindrical rod portion 1051 and a head 1052, and the cross-sectional diameter of the head 1052 is larger than the cross-sectional diameter of the rod portion 1051. The head 1052 abuts against the elastic member 103, and the rod portion 1051 abuts against the transmission screw 101. The connecting sleeve 104 is provided with a stepped hole that matches the shape of the push rod 105, which is used to axially limit the elastic member 103 and the push rod 105.

[0047] like Figure 6 As shown, the connecting sleeve 104 has a through hole and includes at least one vent hole 1043. The vent hole 1043 is arranged radially and penetrates through the section of the through hole where the elastic element 103 is located and the outside of the connecting sleeve. The vent hole 1043 can effectively balance the pressure difference between the inside and outside of the connecting sleeve and prevent the elastic element 103 from failing to contract normally due to excessive air pressure.

[0048] In this embodiment, as Figure 1 As shown, the elastic component also includes an adapter 106 and a gasket 107. The external thread 1061 at one end of the adapter 106 is used to connect with the internal thread 1041 at one end of the connecting sleeve 104. The gasket 107 is located inside the connecting sleeve 104 and its two end faces abut against the adapter 106 and the elastic element 103, respectively.

[0049] like Figure 7 As shown, one end of the adapter 106 is provided with an external thread 1061, and the other end is provided with an external thread 1062. Between the two external threads is a thick rod 1063, and the cross-sectional diameter of the thick rod 1063 is larger than the diameter of the external threads at both ends. This is used for positioning and bearing axial loads, making the threaded connection more stable. Example 2

[0050] This embodiment discloses a screw pump, such as Figure 8 As shown, the device includes the protector 1 in Embodiment 1, as well as a stator 2, a rotor 3, and a drive unit 4. The rotor 3 is located inside the stator 2, and the drive unit 4 achieves oil extraction by driving the rotor 3 to rotate. The protector 1 is located between the rotor 3 and the drive unit 4, with the drive unit 4 located above the protector 1 and the rotor 3 located below the protector 1.

[0051] Optionally, the screw pump also includes an oil pipe fitting 5, which is fixed to the stator 2 and sleeved outside the drive unit 4 and the protector 1. The oil pipe fitting 5 serves as a lifting channel for the crude oil mixture, enabling the crude oil mixture to be smoothly pumped to the oilfield surface.

[0052] In another embodiment, the screw pump of the present invention also includes a positioner, which can limit and adjust the rotor. On the one hand, after the stator and rotor have worn down due to long-term operation, causing the gap to increase, the rotor 3 can be lowered to compensate for the gap, improving the fit between the stator and rotor and thus increasing volumetric efficiency. On the other hand, if the stator and rotor become stuck, the rotor 3 can be raised to increase the gap and unblock the rotor. However, the control of this positioner requires manual operation by the operator, making it difficult to ensure that adjustments are made at all times. In cases of sand jamming, this adjustment method is not timely enough.

[0053] Therefore, the screw pump in this embodiment is designed with a protector 1. The protector 1 can be connected in series with the position controller to jointly adjust the rotor height, or it can be adjusted independently. In this embodiment, when the protector 1 is located between the rotor 3 and the drive unit 4: one end of the protector 1 is connected to the rotor 3 through the transmission screw 101, and the other end of the protector 1 is connected to the drive unit 4 through the adapter 106; or, one end of the protector 1 is connected to the drive unit 4 through the transmission screw 101, and the other end of the protector 1 is connected to the rotor 3 through the adapter 106.

[0054] Specifically, the external thread 1012 at one end of the transmission screw 101 is connected to the rotor 3 or the drive unit 4, and the external thread 1062 at one end of the adapter 106 is connected to the drive unit 4 or the rotor 3.

[0055] In one embodiment, to eliminate the eccentricity caused by the rotation of rotor 3, the screw pump further includes an eccentric rod 6. For example... Figure 1 As shown, one end of the eccentric rod 6 is connected to the rotor 3, and the other end is connected to the protector 1.

[0056] This embodiment uses the example of a protector 1 connected to the rotor 3 at one end via a transmission screw 101 and to the drive unit 4 at the other end via an adapter 106 to illustrate the protection principle of the protector. The specific details are as follows:

[0057] During the operation of the screw pump, the drive unit 4 drives the adapter 106 to rotate. The adapter 106 is fixedly connected to the connecting sleeve 104, which in turn is fixedly connected to the connecting nut 102. Therefore, the connecting nut 102 rotates synchronously with the drive unit 4. The transmission screw 101 is fixedly connected to the rotor 3 or the eccentric rod 6, so the transmission screw 101 rotates synchronously with the rotor 3.

[0058] During normal operation of the screw pump, the drive unit 4 drives the connecting nut 102 to rotate. The connecting nut 102 and the transmission screw 101 are connected by a transmission thread, so the transmission screw 101 tends to move upward. Since the transmission screw 101 is connected to the elastic element 103 by the push rod 105 above it, the elastic element 103 deforms under force and generates a spring force on the push rod 105, which restricts the transmission screw 101 from moving upward. When the torque and the spring force are balanced, the position of the transmission screw 101 in the axial direction of the protector is fixed, and it rotates synchronously with the connecting nut 102, driving the rotor 3 to rotate and work within the stator 2.

[0059] When the sand content increases or the oil thickens during the operation of the screw pump, the torque of the rotor 3 increases, making it more difficult to follow the rotation of the drive unit 4. At this time, the transmission screw 101 and the connecting nut 102 will rotate relative to each other, further compressing the elastic element 103. The transmission screw 101 will move upward until the elastic force of the elastic element 103 and the torque of the transmission screw reach a balance.

[0060] The protector in this application can also be used for real-time compensation of the stator-rotor clearance. In scenarios with only a position controller, the rotor 3 is typically lowered using the position controller after the stator-rotor wear reaches a set value to compensate for the clearance. However, before the stator-rotor wear reaches the set value, the pump efficiency will be affected because the stator-rotor clearance is already larger than the standard value. After adding the protector, when the stator-rotor clearance increases due to wear, the torque of the rotor 3 will decrease, and the elastic element 103 will extend downwards, causing the transmission screw 101 and the rotor 3 to move downwards, thereby compensating for the stator-rotor clearance in real time.

[0061] In summary, the protector 1 can maintain the torque value of the rotor 3 at a set threshold. When the rotor torque value is greater than the set threshold, the elastic element 103 contracts, and the rotor 3 moves upward; when the rotor torque value is less than the set threshold, the elastic element 103 extends, and the rotor moves downward. For example, the set threshold is 800 Nm.

[0062] The value of the set threshold is related to the structure and material of the elastic element 103, the transmission screw 101, and the connecting nut 102. Example 3

[0063] This embodiment is similar to Embodiment 1, and discloses a protector, such as... Figure 9 As shown, the device includes a transmission assembly and an elastic assembly. The transmission assembly uses a threaded connection to convert torque into relative displacement along the axial direction of the protector. The elastic assembly limits the displacement of the transmission assembly by providing elastic force along the axial direction of the protector. The cooperation between the transmission assembly and the elastic assembly ensures that the torque value experienced by the protector 1 is within a set threshold. The transmission assembly includes a transmission screw 101 and a connecting nut 102, and the transmission screw 101 and the connecting nut 102 are connected by a transmission thread.

[0064] The difference from Embodiment 1 is that the elastic component includes an elastic element 103, which is disposed inside the connecting nut 102 and sleeved outside the smooth rod of the transmission screw 101. The two ends of the elastic element 103 respectively abut against the stepped hole and the internal transmission thread 1021 of the connecting nut 102, and can elastically expand and contract within the smooth hole 1023 at one end of the connecting nut 102 along the axial direction of the connecting nut 102.

[0065] In this embodiment, the elastic component also includes an adapter 106, and the external thread 1061 at one end of the adapter 106 is used to make a threaded connection with the internal thread 1022 at one end of the connecting nut 102. Example 4

[0066] This embodiment discloses a screw pump, including the protector 1 in embodiment 3, and also including a stator 2, a rotor 3, and a drive unit 4; the rotor 3 is located inside the stator 2, and the drive unit 4 achieves oil extraction by driving the rotor 3 to rotate. The difference from embodiment 2 is that the protector 1 is located between the rotor 3 and the drive unit 4, and the rotor 3 is located above the protector 1, while the drive unit 4 is located below the protector 1.

[0067] This embodiment uses the example of protector 1 being connected to rotor 3 at one end via adapter 106 and to drive unit 4 at the other end via transmission screw 101 to illustrate the protection principle of protector 1. The specific details are as follows:

[0068] During the operation of the screw pump, the drive unit 4 drives the transmission screw 101 to rotate synchronously. The rotor 3 is fixedly connected to the adapter 106, and the adapter 106 is fixedly connected to the connecting nut 102. Therefore, the connecting nut 102 and the rotor 3 rotate synchronously.

[0069] During normal operation of the screw pump, the drive unit 4 drives the transmission screw 101 to rotate, and the transmission screw 101 and the connecting nut 102 are connected by a transmission thread. Since the height of the drive unit 4 is fixed, the transmission screw 101 cannot move up and down, so the connecting nut 102 tends to move upward. When the connecting nut 102 moves upward, the elastic element 103 is compressed, generating a downward elastic force on the connecting nut 102, which restricts the connecting nut 102 from continuing to move upward. When the torque and the elastic force are balanced, the connecting nut 102 is fixed in the axial position of the protector and rotates synchronously with the transmission screw 101, driving the rotor 3 to rotate and work within the stator 2.

[0070] When the sand content increases or the oil thickens during the operation of the screw pump, the torque of the rotor 3 increases, making it more difficult to follow the rotation of the drive unit 4. At this time, the transmission screw 101 and the connecting nut 102 will rotate relative to each other, further compressing the elastic element 103. The connecting nut 102 moves upward until the elastic force of the elastic element 103 and the torque of the transmission screw reach a balance. Example 5

[0071] In this embodiment, two or more protectors can be connected in series. When two adjacent protectors are connected, the transmission screw 101 of one protector is directly fixed to the adapter 106 of the other protector or connected through other components. This embodiment does not limit this.

[0072] Setting up multiple protectors can increase the adjustment range and setting threshold of the stator-rotor gap without changing the protector structure. For example, a single elastic element 103 of length L can adjust the rotor displacement to h, and n elastic elements 103 of length L can adjust the rotor displacement to nh. If an elastic element 103 of length nL is placed inside a protector, a longer connecting sleeve 104 needs to be manufactured, and the transmission screw 101 and connecting nut 102 also need to be designed to match the length of the elastic element 103. An excessively long rod-shaped or cylindrical structure is not only difficult to manufacture, but also cannot guarantee the manufacturing accuracy.

[0073] It should be noted that the upward and downward movements mentioned in the various embodiments of this application do not refer to vertical movement perpendicular to the ground. Rather, upward movement refers to moving along the screw pump axis towards the end closer to the ground outlet, and downward movement refers to moving along the screw pump axis towards the end farther from the ground outlet. The same principle applies to the terms "above" and "below" in the various embodiments of this application.

[0074] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0075] 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. A protector characterized by The torque is converted into relative displacement along the axial direction of the protector by a transmission assembly, and the displacement of the transmission assembly is limited by an elastic assembly by providing elastic force along the axial direction of the protector, and the cooperation of the transmission assembly and the elastic assembly makes the torque value borne by the protector within a set threshold.

2. The protector of claim 1, wherein, The transmission assembly comprises a transmission screw (101) and a connecting nut (102), and the transmission screw (101) and the connecting nut (102) are connected by a transmission thread.

3. The protector of claim 2, wherein, The elastic assembly comprises an elastic member (103) and a connecting sleeve (104), the elastic member (103) is arranged in the connecting sleeve (104) and can elastically stretch and contract along the axial direction of the connecting sleeve (104).

4. The protector of claim 2, wherein, The elastic assembly comprises an elastic member (103), the elastic member (103) is arranged in the connecting nut (102) and around the polished rod of the transmission screw (101), the two ends of the elastic member (103) are respectively abutted between the stepped hole of the connecting nut (102) and the inner transmission thread (1021), and the elastic member (103) can elastically stretch and contract along the axial direction of the connecting nut (102) in the smooth hole (1023) at one end of the connecting nut (102).

5. The protector of claim 4, wherein, The elastic assembly further comprises an adapter (106), the outer thread one (1061) at one end of the adapter (106) is used for thread connection with the inner thread two (1022) at one end of the connecting nut (102).

6. The protector of claim 3, wherein, The elastic assembly further comprises a jack (105), the jack (105) is located in the connecting sleeve (104), one end of the jack (105) is abutted against the elastic member (103), and the other end of the jack (105) is abutted against the transmission screw (101).

7. The protector of claim 6, wherein, The jack (105) comprises a cylindrical rod part (1051) and a head part (1052), the cross-sectional diameter of the head part (1052) is greater than the cross-sectional diameter of the rod part (1051), the head part (1052) is abutted against the elastic member (103), and the rod part (1051) is abutted against the transmission screw (101); the connecting sleeve (104) is provided with a stepped hole matched with the shape of the jack (105) for axially limiting the elastic member (103) and the jack (105).

8. The protector of claim 3, wherein, The connecting nut (102) is provided with a through hole two, the through hole two is provided with an inner thread two (1022) and an inner transmission thread (1021), the inner thread two (1022) is used for thread connection with the outer thread two (1042) at one end of the connecting sleeve (104), and the inner transmission thread (1021) is used for thread connection with the outer transmission thread (1011) at one end of the transmission screw (101).

9. The protector of claim 3, wherein, The connecting sleeve (104) is provided with a through hole one and at least one air hole (1043), the air hole (1043) is arranged along the radial direction and penetrates the through hole one where the elastic member (103) is located and the outside of the connecting sleeve.

10. The protector of claim 3, wherein, The elastic assembly further comprises a connector (106) and a gasket (107), an outer thread (1061) at one end of the connector (106) is used for threaded connection with an inner thread (1041) at one end of the connecting sleeve (104), and the gasket (107) is located in the connecting sleeve (104) and abuts against the connector (106) and the elastic member (103) at two end faces respectively.

11. A screw pump characterized in that The screw pump comprises the protector according to any one of claims 1-10, further comprising a stator (2), a rotor (3) and a driving part (4); the rotor (3) is located inside the stator (2), the driving part (4) realizes oil extraction by driving the rotor (3) to rotate; the protector (1) is located between the rotor (3) and the driving part (4).

12. The screw pump according to claim 11, characterized in that, one end of the protector (1) is connected with the rotor (3) through the transmission screw (101), and the other end of the protector (1) is connected with the driving part (4) through the connector (106); or, one end of the protector (1) is connected with the driving part (4) through the transmission screw (101), and the other end of the protector (1) is connected with the rotor (3) through the connector (106).

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