A pre-oil-filled series submersible motor

Abstract

The present invention belongs to the technical field of submersible electric pumps for oil production and lifting equipment, and particularly relates to a pre-oiled, serially connected submersible motor. The pre-oiled, serially connected submersible motor comprises an upper motor lead connection seat, an upper motor lower shaft head, a lower motor lead connection head, and a lower motor upper shaft head. The upper motor lead connection seat has a built-in valve stem, and the lower motor lead connection head is connected to a lead pressure plate. When the lower motor lead connection head and the upper motor lead connection seat approach each other, the lead pressure plate pushes the valve stem to move. The upper motor lower shaft head has a built-in ball valve, and the lower motor upper shaft head has a built-in push rod. When the upper motor lower shaft head and the lower motor upper shaft head approach each other, the push rod opens the ball valve. A skeleton oil seal is provided in the annular cavity between the upper motor lead connection seat and the upper motor lower shaft head. The present invention provides a pre-oiled, serially connected submersible motor that eliminates the need for on-site oiling, significantly improves work efficiency, and reduces downhole costs.

Description

Technical Field

[0001] The invention belongs to the technical field of submersible electric pumps for oil production and lifting equipment, and in particular relates to a pre-oil-filled serially connected submersible motor. Background Art

[0002] Existing technologies and defects:

[0003] In recent years, domestic and international markets have increasingly demanded higher on-site construction efficiency and environmental protection for submersible pumps, driving the development of submersible pump units toward faster on-site installation and environmentally friendly features. Currently, the submersible motors in submersible pump units are filled with oil on-site. Due to the complex internal structure and confined space of submersible motors, the on-site oil filling process must be very slow to fully expel air from the motor and ensure it is fully filled with oil. This results in a lengthy filling process, especially in winter and in cold climates, where the increased viscosity of the motor oil further reduces the filling speed and increases the difficulty of operation, severely impacting on-site construction efficiency. Furthermore, oil spillage and splashing are inevitable during the filling process, polluting the on-site environment.

[0004] The difficulty and significance of solving the above technical problems:

[0005] Therefore, based on these problems, it is of great practical significance to provide a pre-oiled series submersible motor that can avoid on-site oil injection, greatly improve work efficiency, and reduce downhole costs. Summary of the Invention

[0006] The purpose of the present invention is to solve the technical problems existing in the known technology and provide a pre-oiled series submersible motor that can avoid on-site oil injection, greatly improve work efficiency and reduce downhole costs.

[0007] The technical solution adopted by the present invention to solve the technical problems existing in the known technology is:

[0008] A pre-oil-filled series submersible motor, the pre-oil-filled series submersible motor comprising an upper motor lead connection seat, an upper motor lower shaft head and a lower motor lead connection head, an upper motor upper shaft head; the upper motor lead connection seat has a built-in valve stem, the lower motor lead connection head is connected to a lead pressure plate, when the lower motor lead connection head and the upper motor lead connection seat are close, the lead pressure plate pushes the valve stem to move, the upper motor lower shaft head has a built-in ball valve, the lower motor upper shaft head has a built-in push rod, when the upper motor lower shaft head and the lower motor upper shaft head are close, the push rod opens the ball valve, and the annular cavity between the upper motor lead connection seat and the upper motor lower shaft head is provided with a skeleton oil seal.

[0009] The oil circuit switches at the valve stem and ball valve, along with the skeleton oil seal and O-rings on the lead wire insulation tube, prevent leakage of the motor oil filled before the serial motor is connected. After the serial motor is connected, the push rod opens the ball valve, the lead wire pressure plate contacts the bottom of the valve stem, and the valve stem moves upward, eliminating the seal and allowing the oil circuits of the upper and lower motors to communicate.

[0010] The present invention can also adopt the following technical solutions:

[0011] In the above-mentioned pre-oil-filled series submersible motor, further, the top of the valve stem is against the spring A, the top of the spring A is against the tube, the top of the tube is installed with a hexagonal pipe plug, and an O-ring is placed between the valve stem and the upper motor lead connection seat.

[0012] Before connecting the motor in series, the valve stem moves downward under the action of spring A, pressing the O-ring to achieve sealing.

[0013] In the above-mentioned pre-oil-filled series submersible motor, further, the upper motor lead connection seat has a built-in lead insulation tube, and the lead insulation tube and the upper motor lead connection seat are sealed by a lead insulation tube O-ring.

[0014] In the above-mentioned pre-oil-filled series submersible motor, further, the ball valve includes a limit plate, a spring B, a steel ball and a valve body. A ball valve inner hole is opened in the center of the valve body, and the top of the spring B is against the limit plate. Before the series motor is docked, the spring B presses the steel ball on the ball valve inner hole to achieve sealing. After the ball valve is assembled, it is installed as a whole into the inner hole of the lower shaft head of the upper motor.

[0015] In the above-mentioned pre-oil-filled serial submersible motor, further, the ball valve is fixed to the inner hole of the lower shaft head of the upper motor through threaded fitting, and is sealed by a lead washer.

[0016] In the above-mentioned pre-oil-filled serial submersible motor, further, there is a gap between the push rod and the valve body, and there is a gap between the upper small cylinder at the top of the push rod and the inner hole of the ball valve.

[0017] In the above-mentioned pre-oil-filled series submersible motor, further, the upper shaft head of the lower motor has a built-in positioning block, the positioning block has a plurality of through holes in the vertical direction of the circumference, and the upper circumferential surface of the valve body has a plurality of through holes evenly opened in the radial direction.

[0018] In the above-mentioned pre-oil-filled serial submersible motor, further, the positioning block is fixed to the upper shaft head and the push rod of the lower motor by threaded connection.

[0019] In the above-mentioned pre-oil-filled serial submersible motor, further, the upper shaft head of the lower motor is provided with an external spline sleeve, and the inner diameter of the spline sleeve is consistent with the outer diameter of the lower shaft head of the upper motor.

[0020] In summary, the present invention has the following advantages and positive effects:

[0021] 1. The present invention can be fully filled with oil in advance before being transported to the site. The series-connected submersible motor adopts two oil circuit switches. Before the motors are connected, the two oil circuit switches are closed. The valve stem seal is achieved by spring A pressing the valve stem and then pressing the O-ring to achieve sealing. The ball valve seal is achieved by spring B pressing the steel ball against the inner hole of the ball valve to achieve sealing. The lead insulation tube and the annular cavity are sealed by the lead insulation tube O-ring and the skeleton oil seal respectively, so that the motor oil does not leak. After the motors are connected, the ball valve is opened, the valve stem moves up, the seal fails, the two oil circuits are opened, and the oil circuits of the upper and lower motors are connected. At this time, the inside of the series-connected motor is full of motor oil, which eliminates the problem of re-injecting motor oil when the existing series-connected submersible motor is lowered into the well, saves on-site oil filling time, improves oil filling quality, especially in winter and high-altitude cold areas, greatly reduces the labor intensity of operators, greatly improves on-site construction efficiency, and avoids pollution to the on-site environment.

[0022] 2. The ball valve oil circuit switch in the present invention can be integrally installed into the inner hole of the lower shaft head of the upper motor, which is convenient and quick, reduces the difficulty of installation, and is convenient for later maintenance; the valve stem oil circuit switch has a simple structure, is easy to assemble, and has reliable functions.

[0023] 3. The overall structure of the present invention is simple and easy to implement. Compared with the ordinary series-connected submersible motor, only the upper motor lead connection seat, the upper motor lower shaft head and the lower motor upper shaft head need to be modified. Other parts can be shared, with strong interchangeability, which greatly reduces the manufacturing cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The technical solutions of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. However, it should be understood that these drawings are designed for illustrative purposes only and are not intended to limit the scope of the present invention. Furthermore, unless otherwise specified, these drawings are intended only to conceptually illustrate the structures described herein and are not necessarily drawn to scale.

[0025] Figure 1 This is a structural diagram of the upper motor before the pre-oil-filled series submersible motor is connected;

[0026] Figure 2 This is a structural diagram of the lower motor before the pre-oil-filled series submersible motor is connected to the submersible motor in the present invention;

[0027] Figure 3 This is a schematic diagram of the structure of the pre-oil-filled series submersible motor after docking in the present invention;

[0028] Figure 4 This is a schematic diagram of the ball valve opening after the pre-oil-filled series submersible motor is connected;

[0029] Figure 5 It is a schematic diagram of the upward movement of the valve stem after the pre-oil injection and the submersible motor are connected.

[0030] In the picture:

[0031] 1- Hexagon socket pipe plug, 2- upper motor lead connection seat, 3- tube, 4- spring A, 5- O-ring, 6- valve stem, 7- spline sleeve, 8- lead pressure plate, 9- lower motor lead connector, 10- lead insulation tube, 11- skeleton oil seal, 12- upper motor lower shaft head, 13- ball valve, 14- lead washer, 15- lead insulation tube O-ring, 16- push rod, 17- positioning block, 18- lower motor upper shaft head, 19- limit plate, 20- spring B, 21- steel ball, 22- valve body. DETAILED DESCRIPTION

[0032] The following is combined Figures 1 to 5 The present invention will be described in detail.

[0033] In order to further understand the content, features and effects of the present invention, the following embodiments are given as examples and described in detail with reference to the accompanying drawings:

[0034] Example 1:

[0035] Depend on Figure 1 、 Figure 2 and Figure 3 As shown, a pre-oiled, serially connected submersible motor comprises an upper motor lead connector 2, an upper motor lower shaft stub 12, a lower motor lead connector 9, and a lower motor upper shaft stub 18. The motor leads pass through an insulated lead tube 10 built into the upper motor lead connector 2 (copper plugs are attached to the motor leads, mating with sockets on the lower motor to complete the electrical connection). An O-ring 15 seals the lead tube 10 and the upper motor lead connector 2. The upper motor lead connector 2 houses a built-in valve stem 6, the top of which bears against a spring A4, which in turn bears against a tube 3. A hexagonal socket plug 1 is attached to the top of the tube 3. An O-ring 5 is interposed between the valve stem 6 and the upper motor lead connector 2. The annular cavity formed between the exterior of the upper motor lower shaft stub 12 and the inner bore of the upper motor lead connector 2 is sealed by a skeleton oil seal 11.

[0036] The lower shaft head 12 of the upper motor contains a built-in ball valve 13, which comprises a stop plate 19, a spring B20, a steel ball 21, and a valve body 22. Installation is as follows: The steel ball 21, spring B20, and stop plate 19 are sequentially installed into the valve body 22, and the stop plate 19 is then riveted securely. The ball valve 13 is threadedly secured to the inner bore of the lower shaft head 12 of the upper motor and sealed with a lead washer 14, making installation quick and easy. Four radially spaced through holes are uniformly distributed on the upper circumference of the valve body 22, ensuring that the oil passages between the shaft bores of the upper and lower motors are connected when the ball valve is open.

[0037] The lower motor's upper shaft stub (18) houses a positioning block (17) and a push rod (16), with a splined sleeve (7) mounted externally. The positioning block (17) has several vertical holes around its circumference to ensure oil flow connectivity between the shaft holes after the upper and lower motors are connected in series. The positioning block (17) is threadedly secured to the lower motor's upper shaft stub (18) and push rod (16). A gap exists between the push rod (16) and the valve body (22), and between the small cylinder at the top of the push rod (16) and the inner hole of the ball valve. A lead pressure plate (8) is connected to the lower motor's lead connector (9). The inner diameter of the splined sleeve (7) matches the outer diameter of the upper motor's lower shaft stub (12).

[0038] Before connecting the motor in series (as shown in the attached manual) Figure 1 and instructions attached Figure 2 ), under the action of spring A4, the valve stem 6 moves downward, compressing the O-ring 5 to achieve sealing and close the oil circuit; the steel ball 21 in the ball valve 13 blocks the inner hole of the valve body 22 under the action of spring B20, achieving sealing and closing the shaft hole oil circuit, thereby ensuring that the motor oil will not leak when the motor oil is filled in the upper section.

[0039] After connecting the motors in series (see the attached manual) Figure 3 To the instruction manual Figure 5 ), the bottom end of the valve stem 6 contacts the lead pressure plate 8, and the valve stem 6 moves upward. At this time, the O-ring 5 will move upward with the valve stem 6, and a gap will be generated between the O-ring 5 and the upper motor lead connection seat 2, causing the seal to fail, thereby opening the oil circuit; the push rod 16 enters the interior of the ball valve 13, pushes open the steel ball 21, and the seal fails, thereby opening the shaft hole oil circuit.

[0040] After the two oil circuits are opened, the oil circuits of the upper and lower motors are connected. After the series motors are running, the internal temperature rises and the motor oil expands. The motor oil in the lower motor can flow into the upper motor through the gap between the O-ring 5 and the upper motor lead connector 2, the spring A4, the inner hole of the tube 3, and the inner hole of the hexagonal pipe plug 1. The motor oil in the lower motor can also flow into the shaft hole of the upper motor through the vertical through-holes in the circumference of the positioning block 17, the gap between the push rod 16 and the valve body 22, the gap between the upper end small cylinder of the push rod 16 and the inner hole of the ball valve, the gap between the steel ball 21 and the inner hole of the ball valve, and the radial through-holes on the upper circumferential surface of the valve body 22, thereby ensuring that the oil circuit is unobstructed after the motors are running and avoiding motor failure. After the series-connected motor stops running, the internal motor oil cools down and the motor oil flows in the opposite direction to the above direction, thereby ensuring that the motor oil in the upper motor flows smoothly into the lower motor and that the lower motor is filled with motor oil. This prevents the thrust bearing of the lower motor from being worn out due to lack of motor oil when the series-connected motor is started again.

[0041] In summary, the present invention provides a pre-oiled serially connected submersible motor that can eliminate on-site oil injection, greatly improve work efficiency, and reduce downhole costs.

[0042] The above embodiments describe the present invention in detail, but the contents described are only preferred embodiments of the present invention and should not be considered to limit the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A pre-oil-filled series submersible motor, characterized by: The pre-oil-filled series submersible motor includes an upper motor lead connection seat, an upper motor lower shaft head, a lower motor lead connection head, and a lower motor upper shaft head. The upper motor lead connection seat has a built-in valve stem, and the lower motor lead connection head is connected to a lead pressure plate. When the lower motor lead connection head and the upper motor lead connection seat are close to each other, the lead pressure plate pushes the valve stem to move. The upper motor lower shaft head has a built-in ball valve, and the lower motor upper shaft head has a built-in push rod. When the upper motor lower shaft head and the lower motor upper shaft head are close to each other, the push rod opens the ball valve. The annular cavity between the upper motor lead connection seat and the upper motor lower shaft head is provided with a skeleton oil seal. An O-ring is placed between the valve stem and the upper motor lead connection seat. The upper motor lead connection seat has a built-in lead insulation tube. The lead insulation tube and the upper motor lead connection seat are sealed by the lead insulation tube O-ring. After the ball valve is assembled, it is installed as a whole into the inner hole of the lower shaft head of the upper motor, and an annular groove is added to the upper motor lead connection seat.

2. The pre-oil-filled series submersible motor according to claim 1, characterized in that: The top of the valve stem abuts against the spring A, the top of the spring A abuts against the tube, and a hexagonal pipe plug is installed on the top of the tube.

3. The pre-oil-filled series submersible motor according to claim 1, characterized in that: The ball valve includes a limit plate, a spring B, a steel ball and a valve body. A ball valve inner hole is opened in the center of the valve body. The top of the spring B is against the limit plate. Before the serial motor is connected, the spring B presses the steel ball against the ball valve inner hole to achieve sealing.

4. The pre-oil-filled series submersible motor according to claim 3, characterized in that: The ball valve is fixed to the inner hole of the lower shaft head of the upper motor through threaded fitting, and is sealed by a lead washer.

5. The pre-oil-filled series submersible motor according to claim 1, characterized in that: There is a gap between the push rod and the valve body, and there is a gap between the small cylinder at the upper end of the top of the push rod and the inner hole of the ball valve.

6. The pre-oil-filled series submersible motor according to claim 5, characterized in that: A positioning block is built into the upper shaft head of the lower motor. A plurality of through holes are opened in the vertical direction of the circumference of the positioning block. A plurality of through holes are evenly opened in the radial direction on the circumferential surface of the upper portion of the valve body.

7. The pre-oil-filled series submersible motor according to claim 6, characterized in that: The positioning block is fixed to the upper shaft head and the push rod of the lower motor through threaded connection.

8. The pre-oil-filled series submersible motor according to claim 1, characterized in that: The upper shaft head of the lower motor is provided with an external spline sleeve, and the inner diameter of the spline sleeve is consistent with the outer diameter of the lower shaft head of the upper motor.

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