Huff and puff oil extraction device of submersible direct-drive screw pump

Abstract

The utility model provides a submersible direct-drive screw pump huff and puff oil extraction device, which relates to the technical field of oil extraction devices and comprises a fixed base, guide components are mounted on two sides of the top of the fixed base, a sliding component is mounted between the two guide components, and a submersible pump is mounted in the sliding component. A screw pump is arranged at the top of the oil-submerged pump, by arranging the guide assembly and the sliding assembly, the oil-submerged direct-drive screw pump huff and puff oil extraction device can stably slide along an optical axis in the ascending and descending processes, the situation that a surrounding well body is impacted due to slow movement is reduced, and therefore vibration generated by the device is reduced, and the service life of the oil-submerged direct-drive screw pump huff and puff oil extraction device is prolonged. Internal precision elements are effectively protected, and the service life of equipment is prolonged.

Description

Technical Field

[0001] This utility model relates to the field of oil production equipment technology, and in particular to a submersible direct-drive screw pump throughput oil production device. Background Technology

[0002] Water injection huff and puff technology is a method of oil recovery where water is injected into production wells to restore formation pressure when formation pressure drops and production is very low. After the well is shut in for a certain period of time, the oil is displaced by capillary action and the oil in the matrix. The pressure drop at the well opening allows the displaced oil and some of the injected water to be extracted together. It is an effective method for improving the recovery rate of small oil reservoirs without energy replenishment. To date, this technology has been applied in some oilfields in China and has achieved certain economic benefits, with the prospect of further promotion and application.

[0003] According to a Chinese patent document (authorization announcement number: CN208669581U), a submersible direct-drive screw pump injection oil production device relates to the field of mechanical oil production technology. Specifically, it is a submersible direct-drive screw pump injection oil production device, including a support base. Shock-absorbing devices are fixedly connected to both ends of the lower surface of the support base. A support pipe is fixedly connected to the upper surface of the support base. A first connecting pipe is fixedly connected to one side of the support pipe, and a fixing block is fixedly connected to the other side of the support pipe. A second connecting pipe is fixedly connected to the end of the first connecting pipe away from the support pipe. This submersible direct-drive screw pump injection oil production device, through the setting of an anti-collision protection device, ensures that when the submersible pump is frequently started and dropped using water injection injection oil production technology, the anti-collision shell on the anti-collision protection device buffers and releases the vibration generated by the submersible pump hitting the borehole wall through the cooperation of the shock-absorbing pipe and the first spring, thereby protecting the submersible pump.

[0004] However, the above solution still has the following shortcomings when implemented:

[0005] Because the device is hoisted into the well, it is inevitable that there will be varying degrees of slow movement during the ascent and descent, which may cause the equipment to collide with the surrounding well body. Although it is equipped with an anti-collision structure, it will still generate some vibration, which may damage the internal precision components over time.

[0006] Therefore, we propose a submersible direct-drive screw pump for oil production. Utility Model Content

[0007] The purpose of this invention is to address the shortcomings of the existing technology. Since the device is hoisted into the well, it is inevitable that there will be varying degrees of slow movement during the ascent and descent, which will cause the device to collide with the surrounding well body. Although an anti-collision structure is configured, some vibration will still occur, which will cause damage to the internal precision components over time.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] A submersible direct-drive screw pump for oil production includes a fixed base, guide components are installed on both sides of the top of the fixed base, a sliding component is installed between the two guide components, a submersible pump is installed inside the sliding component, and a screw pump is provided on the top of the submersible pump.

[0010] The guide assembly includes a fixing frame, a fixing screw is installed inside the fixing frame, a plurality of optical axes are provided at the connection of the fixing screw, a connecting screw is provided at the bottom of the plurality of optical axes, and a connecting thread groove is provided at the top of the plurality of optical axes.

[0011] The sliding assembly includes a fixed ring, with sliding blocks installed on both side walls of the fixed ring. Each of the two sliding blocks has a lubrication pump inside, and an oil delivery pipe is installed at the output end of each of the two lubrication pumps. Several connecting rods are installed at the bottom of each of the two sliding blocks, and a cleaning and lubrication slider is connected to the bottom of each of the several connecting rods.

[0012] As a preferred embodiment of this utility model, the connection of the submersible pump is further provided with a main equipment assembly, which is fixedly connected to the fixed base. The main equipment assembly is used to discharge the oil collected by the submersible pump.

[0013] As a preferred embodiment of this utility model, the fixing screw is threadedly connected to the fixing frame, and the two connecting threaded grooves are connected by the connecting screw being inserted into the connecting threaded groove. The connecting screw and the connecting threaded groove are threadedly connected.

[0014] As a preferred embodiment of this utility model, the two sliding blocks and the fixed ring are designed as an integral unit, and the two sliding blocks are slidably connected to the optical axis.

[0015] As a preferred embodiment of this utility model, the cleaning and lubrication slider is fixedly connected to the sliding block through a plurality of connecting rods, and the cleaning and lubrication slider is used to clean contaminants on the optical axis.

[0016] As a preferred embodiment of this utility model, the lubrication pump is used to deliver the internal lubricating oil to the interior of the cleaning lubrication slider, and the oil flows out to the optical axis through the lubrication hole inside the cleaning lubrication slider to lubricate it.

[0017] Compared with the prior art, the beneficial effects of this utility model are:

[0018] In this invention, by setting up a guide component and a sliding component, the submersible direct-drive screw pump oil production device can slide relatively stably along the optical axis during the rising and falling process, reducing the situation of impacting the surrounding well body due to slow movement, thereby reducing the vibration generated by the equipment, effectively protecting the internal precision components, and extending the service life of the equipment.

[0019] Cleaning the lubricating slider can remove contaminants from the optical axis, keeping it clean and preventing contaminants from adversely affecting the sliding process, ensuring the normal operation of the device, and also reducing additional wear and malfunctions caused by contaminants. Attached Figure Description

[0020] Figure 1 A schematic diagram illustrating the relationship between the main body and the ground of a submersible direct-drive screw pump for oil production, provided by this utility model;

[0021] Figure 2 A schematic diagram of the main structure of a small-volume, high-power drilling rig provided by this utility model;

[0022] Figure 3 This utility model provides a submersible direct-drive screw pump throughput oil production device. Figure 2 Enlarged schematic diagram of the structure at point A in the middle;

[0023] Figure 4 A schematic diagram of the optical axis unfolding of a submersible direct-drive screw pump for oil production provided by this utility model;

[0024] Figure 5 This utility model provides a schematic diagram of the connection between the fixing frame and the fixing screw in a submersible direct-drive screw pump for oil production.

[0025] Legend: 1. Fixed base; 2. Fixed frame; 3. Fixed screw; 4. Optical shaft; 5. Connecting screw; 6. Connecting threaded groove; 7. Fixed ring; 8. Sliding block; 9. Lubrication pump; 10. Oil delivery pipe; 11. Cleaning and lubrication slider; 12. Connecting rod; 13. Submersible oil pump; 14. Screw pump; 15. Main assembly of equipment. Detailed Implementation

[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the protection scope of the present utility model.

[0027] To facilitate understanding of this utility model, a more comprehensive description of this utility model will be provided below with reference to relevant embodiments, and several embodiments of this utility model will be given. However, this utility model can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of this utility model more thorough and complete.

[0028] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items. Example

[0030] like Figure 1-5 As shown, this utility model provides a technical solution: a submersible direct-drive screw pump oil extraction device, mainly used for oil extraction operations. It includes a fixed base 1, which stabilizes the entire device. Guide components are installed on both sides of the top of the fixed base 1. The guide components act like tracks, providing clear directional guidance for the vertical movement of the device. A sliding component is installed between the two guide components, which can slide smoothly along the guide components. A submersible pump 13 is installed inside the sliding component. The submersible pump 13 can be submerged into the oil well to collect crude oil from the ground. A screw pump 14 is also installed on top of the submersible pump 13. The screw pump 14 further transports and pressurizes the collected crude oil to meet the needs of subsequent extraction and transportation.

[0031] The stability of the fixed base 1 is the foundation for the normal operation of the entire device. It can resist various forces generated during the operation of the device and prevent the device from shaking and tilting. The cooperation of the guide component and the sliding component allows the device to move along a predetermined path during the rising and falling process, avoiding the device from swinging randomly in the well and thus reducing collisions with the surrounding well body. The submersible pump 13 uses its own suction to draw crude oil from underground to the surface, while the screw pump 14 transports and pressurizes the crude oil through the rotation of the screw, thereby improving the crude oil transportation efficiency.

[0032] The guiding assembly mainly consists of a fixed frame 2, a fixed screw 3, an optical shaft 4, a connecting screw 5, and a connecting threaded groove 6. The fixed frame 2 is the supporting structure of the guiding assembly. It is installed on the fixed base 1 and provides a fixed support point for the entire guiding assembly. The fixed screw 3 is installed inside the fixed frame 2. The fixed screw 3 is tightly connected to the fixed frame 2 by threads. This threaded connection method is not only easy to install, but also provides sufficient connection strength to ensure that the fixed screw 3 and the fixed frame 2 will not easily loosen. Several optical shafts 4 are provided at the connection of the fixed screw 3. The optical shaft 4 is the core component of the guiding assembly. Its surface is smooth and can provide a low-friction sliding surface for the sliding assembly. Each optical shaft 4 has a connecting screw 5 at the bottom and a connecting threaded groove 6 at the top. Through the cooperation of the connecting screw 5 and the connecting threaded groove 6, multiple optical shafts 4 can be connected in sequence to form a continuous guiding track to adapt to the needs of oil wells at different depths.

[0033] The supporting function of the fixed frame 2 ensures the overall stability of the guide assembly. The threaded connection between the fixed screw 3 and the fixed frame 2 utilizes the self-locking characteristic of the thread, making the connection more secure. The smooth surface of the optical axis 4 reduces the friction between the sliding assembly and the guide assembly, improving the smoothness of sliding. The threaded connection between the connecting screw 5 and the connecting threaded groove 6 makes the connection of the optical axis 4 convenient and quick, and ensures the strength and accuracy of the connection, ensuring the continuity and stability of the entire guide track.

[0034] The sliding assembly includes a fixed ring 7, sliding blocks 8, a lubrication pump 9, an oil supply pipe 10, and a cleaning and lubrication slider 11. The fixed ring 7 is the main structure of the sliding assembly, used to install the submersible oil pump 13 and fix the submersible oil pump 13 inside the sliding assembly. Sliding blocks 8 are installed on both sides of the fixed ring 7. The two sliding blocks 8 are integrated with the fixed ring 7. This design makes the connection between the sliding blocks 8 and the fixed ring 7 tighter and can better transmit force and motion. The lubrication pump 9 is installed inside the two sliding blocks 8. The lubrication pump 9 is like a small oil supply station. It stores lubricating oil inside. The output end of the lubrication pump 9 is installed with an oil supply pipe 10. The oil supply pipe 10 is used to transport the lubricating oil in the lubrication pump 9 to the interior of the cleaning and lubrication slider 11. Several connecting rods 12 are installed at the bottom of the two sliding blocks 8. The bottom of the several connecting rods 12 is connected to the cleaning and lubrication slider 11. The cleaning and lubrication slider 11 is in close contact with the optical axis 4 and can clean and lubricate the optical axis 4.

[0035] The function of the retaining ring 7 is to fix the submersible pump 13 and ensure that the submersible pump 13 remains stable during sliding. The one-piece design of the sliding block 8 can improve the overall rigidity and stability of the sliding assembly. The lubrication pump 9 delivers lubricating oil to the cleaning and lubrication slider 11 through the oil supply pipe 10. The lubrication effect of the lubricating oil can reduce the friction between the sliding block 8 and the optical shaft 4, reduce wear. The close contact between the cleaning and lubrication slider 11 and the optical shaft 4 can clean the contaminants on the surface of the optical shaft 4 in time, ensure the cleanliness of the surface of the optical shaft 4, and further improve the smoothness of sliding.

[0036] At the connection point of the submersible pump 13, there is also a main equipment assembly 15. The main equipment assembly 15 is fixed together with the fixed base 1 by a firm connection to ensure that the main equipment assembly 15 will not shake or shift during operation. The main function of the main equipment assembly 15 is to discharge the oil collected by the submersible pump 13. After the submersible pump 13 collects crude oil from the ground to the surface, the main equipment assembly 15 will perform a series of processing and transportation of the crude oil, such as preliminary filtration, separation and pressurization of the crude oil, and then transport the processed crude oil to the subsequent storage and transportation equipment.

[0037] The fixed connection between the main equipment assembly 15 and the fixed base 1 ensures its stability during operation and can withstand the pressure and impact generated during crude oil transportation. The principle of the main equipment assembly 15 in processing and transporting crude oil is based on fluid mechanics and mechanical principles. Through internal pipes, valves and pumps, crude oil is effectively controlled and transported to ensure that crude oil can be smoothly transported from the oil well to the destination.

[0038] The fixing screw 3 and the fixing bracket 2 are connected by a thread. This connection method has the advantages of convenient installation and easy disassembly. During installation, simply screw the fixing screw 3 into the threaded hole of the fixing bracket 2 and rotate the fixing screw 3 to make it tightly connected with the fixing bracket 2. The two optical shafts 4 are connected by connecting screws 5 inserted into the connecting threaded grooves 6. The connecting screws 5 and the connecting threaded grooves 6 are also connected by threads. When connecting the optical shafts 4, align the connecting screw 5 at the bottom of one optical shaft 4 with the connecting threaded groove 6 at the top of the other optical shaft 4, and then rotate the optical shaft 4 to screw the connecting screw 5 into the connecting threaded groove 6 until the two are tightly connected. This connection method not only ensures the connection strength between the optical shafts 4, but also ensures the coaxiality of the optical shafts 4, so that the sliding component can slide smoothly on the optical shafts 4.

[0039] The principle of threaded connection is to use the helix and tooth profile of the thread to generate friction and axial force between the threads through rotation, thereby achieving tightness and reliability of the connection. In the connection between the fixed screw 3 and the fixed bracket 2, and between the connecting screw 5 and the connecting thread groove 6, the self-locking characteristic of the thread ensures that the connection will not easily loosen when subjected to external force, thus ensuring the overall stability and reliability of the guide assembly.

[0040] The two sliding blocks 8 and the fixed ring 7 are integrated into one piece. This design makes the sliding blocks 8 and the fixed ring 7 a whole, which can work together better. The two sliding blocks 8 are slidably connected to the optical axis 4. The sliding blocks 8 can slide up and down along the surface of the optical axis 4. When the sliding assembly rises or falls under the guidance of the guide assembly, the sliding cooperation between the sliding blocks 8 and the optical axis 4 ensures the smooth movement of the device. Since the surface of the optical axis 4 is smooth, the sliding blocks 8 are subject to less friction during the sliding process, which can achieve smoother sliding.

[0041] The integrated design improves the connection strength and rigidity between the sliding block 8 and the fixed ring 7, enabling them to share the load when subjected to force, thus avoiding shaking and damage caused by weak connection. The sliding connection between the sliding block 8 and the optical axis 4 is based on the principle of sliding friction. The smooth surface of the optical axis 4 reduces the coefficient of sliding friction, reduces energy loss during sliding, and improves the operating efficiency of the device.

[0042] The cleaning and lubrication slider 11 is fixedly connected to the sliding block 8 via several connecting rods 12. This fixed connection ensures the relative position stability between the cleaning and lubrication slider 11 and the sliding block 8, allowing it to slide along the optical axis 4 together with the sliding block 8. The main function of the cleaning and lubrication slider 11 is to clean contaminants on the optical axis 4. In the oil well environment, dust, oil, and other contaminants easily adhere to the surface of the optical axis 4. These contaminants can affect the smoothness of sliding between the sliding block 8 and the optical axis 4, and may even aggravate the wear between them. During the sliding process, the cleaning and lubrication slider 11 will come into close contact with the surface of the optical axis 4. Through its own structure and material properties, it will scrape off or adsorb the contaminants on the surface of the optical axis 4, keeping the surface of the optical axis 4 clean.

[0043] The fixed connection between the cleaning and lubrication slider 11 and the sliding block 8 enables them to move synchronously, ensuring that the cleaning and lubrication slider 11 can clean the optical axis 4 in a timely manner. The cleaning principle of the cleaning and lubrication slider 11 is mainly based on the contact pressure and friction between it and the surface of the optical axis 4 to separate the contaminants from the surface of the optical axis 4. At the same time, the material of the cleaning and lubrication slider 11 may have the property of adsorbing contaminants, which can further improve the cleaning effect.

[0044] The main function of the lubrication pump 9 is to deliver the internally stored lubricating oil to the interior of the cleaning and lubrication slider 11. The lubrication pump 9 generates pressure through its internal mechanical structure or electric device to draw the lubricating oil from the storage chamber and then deliver it to the interior of the cleaning and lubrication slider 11 through the oil delivery pipe 10. The cleaning and lubrication slider 11 is provided with lubrication holes, through which the lubricating oil flows to the optical axis 4 to lubricate the optical axis 4. The lubricating oil forms a lubricating film on the surface of the optical axis 4, which can reduce the direct contact between the sliding block 8 and the optical axis 4, reduce friction, reduce wear, and at the same time play a role in rust prevention and sealing.

[0045] The working principle of the lubrication pump 9 is based on the pressure transmission principle in fluid mechanics. By generating a pressure difference, it delivers lubricating oil to a designated location. The lubricating film formed on the surface of the optical shaft 4 utilizes the lubricating properties of the lubricating oil. It can play a buffering and isolation role between the sliding block 8 and the optical shaft 4, reducing friction and wear between the two and improving the service life and operating efficiency of the device.

[0046] Compared with the prior art, this utility model has significant advantages. By setting up a guide component and a sliding component, the submersible direct-drive screw pump 14 can slide relatively stably along the optical axis 4 during the rising and falling process. The guide component provides a clear sliding track for the sliding component, so that the device will not shake randomly during operation. When the device rises or falls in the well, the sliding component slides along the optical axis 4, reducing the possibility of collision with the surrounding well body due to slow movement. In the prior art, the device is prone to shaking and collision during the rising and falling process, resulting in large vibrations. This utility model effectively reduces the vibration generated by the device through a stable sliding method. The vibration generated by the device can damage the internal precision components. Long-term vibration may cause the precision components to loosen, shift or even be damaged. This utility model effectively protects the internal precision components by reducing vibration and extends the service life of the device.

[0047] The cleaning and lubrication slider 11 can clean contaminants on the optical axis 4, keeping the optical axis 4 clean. In the oil well environment, various contaminants easily adhere to the surface of the optical axis 4. These contaminants can affect the smoothness of sliding between the sliding block 8 and the optical axis 4. If there are contaminants on the surface of the optical axis 4, the sliding block 8 will be hindered during sliding, or even jam, affecting the normal operation of the device. The cleaning and lubrication slider 11 can clean the contaminants on the surface of the optical axis 4 in time during sliding, avoiding the contaminants from having an adverse effect on the sliding process. At the same time, the presence of contaminants will aggravate the wear between the sliding block 8 and the optical axis 4. After the cleaning and lubrication slider 11 cleans the contaminants, it reduces the additional wear and failures caused by contaminants, ensures the normal operation of the device, and improves the reliability and stability of the device.

[0048] The cooperation between the guide assembly and the sliding assembly utilizes the principles of track guidance and sliding friction, making the device more stable during operation and reducing collisions and vibrations. The cleaning and lubrication slider 11 cleans contaminants based on contact friction and adsorption. Through contact with the surface of the optical axis 4, contaminants are separated from the surface of the optical axis 4 and adsorbed or scraped off.

[0049] Work process summary

[0050] Device installation: First, install the fixed base 1 in a suitable position. Then, install guide components on both sides of the top of the fixed base 1. Screw the fixing screw 3 into the fixing frame 2. Then, connect multiple optical axes 4 in sequence through the connecting screw 5 and the connecting threaded groove 6. Next, install the sliding component and slide the sliding block 8 to the optical axis 4. At the same time, install the submersible pump 13 inside the fixing ring 7. Fix the main body assembly 15 to the fixed base 1 and connect it to the submersible pump 13.

[0051] Oil production preparation: Start the lubrication pump 9. The lubrication pump 9 delivers the internal lubricating oil to the interior of the cleaning and lubrication slider 11 through the oil delivery pipe 10. The lubricating oil flows out to the optical axis 4 through the lubrication hole inside the cleaning and lubrication slider 11 to lubricate the optical axis 4.

[0052] Oil extraction operation: Submersible pump 13 is submerged in the oil well to collect crude oil from underground to the surface. The main equipment assembly 15 processes and discharges the oil collected by submersible pump 13, such as performing preliminary filtration, separation and pressurization operations. Then, the processed crude oil is transported to subsequent storage and transportation equipment. During the oil extraction process, the sliding component rises or falls along the optical axis 4 to realize the movement of the device. The cleaning and lubrication slider 11 cleans the contaminants on the optical axis 4 during the sliding process to keep the optical axis 4 clean.

[0053] Maintenance and upkeep: Regularly inspect all components of the device, such as the guide assembly, sliding assembly, submersible pump 13, screw pump 14 and main equipment assembly 15, to ensure their normal operation. Regularly change the lubricating oil in the lubrication pump 9 to ensure lubrication effect. Check and clean the wear of the lubrication slider 11 and replace it in time if necessary.

[0054] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A submersible direct-drive screw pump for oil production, comprising a fixed base (1), characterized in that: Guide components are installed on both sides of the top of the fixed base (1), and a sliding component is installed between the two guide components. A submersible pump (13) is installed inside the sliding component, and a screw pump (14) is provided on the top of the submersible pump (13). The guide assembly includes a fixing frame (2), a fixing screw (3) is installed inside the fixing frame (2), a plurality of optical axes (4) are provided at the connection of the fixing screw (3), a connecting screw (5) is provided at the bottom of the plurality of optical axes (4), and a connecting thread groove (6) is provided at the top of the plurality of optical axes (4). The sliding assembly includes a fixed ring (7), and sliding blocks (8) are installed on both sides of the fixed ring (7). Lubrication pumps (9) are installed inside the two sliding blocks (8). Oil pipes (10) are installed at the output ends of the two lubrication pumps (9). Several connecting rods (12) are installed at the bottom of the two sliding blocks (8). Cleaning and lubrication sliders (11) are connected to the bottom of the several connecting rods (12).

2. The submersible direct-drive screw pump injection oil production device according to claim 1, characterized in that: The submersible pump (13) is also provided with a main equipment assembly (15) at the connection point. The main equipment assembly (15) is fixedly connected to the fixed base (1). The main equipment assembly (15) is used to discharge the oil collected by the submersible pump (13).

3. The submersible direct-drive screw pump injection oil production device according to claim 2, characterized in that: The fixing screw (3) is threadedly connected to the fixing frame (2), and the two connecting threaded grooves (6) are connected by the connecting screw (5) inserted into the connecting threaded groove (6). The connecting screw (5) and the connecting threaded groove (6) are threadedly connected.

4. The submersible direct-drive screw pump injection oil production device according to claim 3, characterized in that: The two sliding blocks (8) and the fixed ring (7) are integrated into one piece, and the two sliding blocks (8) are slidably connected to the optical axis (4).

5. The submersible direct-drive screw pump injection oil production device according to claim 4, characterized in that: The cleaning and lubrication slider (11) is fixedly connected to the sliding block (8) through several connecting rods (12), and the cleaning and lubrication slider (11) is used to clean contaminants on the optical axis (4).

6. The submersible direct-drive screw pump injection oil production device according to claim 5, characterized in that: The lubrication pump (9) is used to deliver the internal lubricating oil to the interior of the cleaning lubrication slider (11), and to the optical axis (4) through the lubrication hole inside the cleaning lubrication slider (11) for lubrication.

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