An environmentally friendly, leak-free submersible motor protector

Abstract

The present invention belongs to the technical field of submersible electric pumps, and in particular, relates to an environmentally friendly, leak-free submersible motor protector, the environmentally friendly, leak-free submersible motor protector comprising a pressure regulating chamber, the pressure regulating chamber comprising an inner pressure regulating chamber chamber and an outer pressure regulating chamber chamber, the inner pressure regulating chamber chamber being the internal space of a pressure regulating chamber capsule, the outer pressure regulating chamber chamber being the space between the pressure regulating chamber capsule and an outer shell, the inner pressure regulating chamber chamber being in communication with external well fluid, and the outer pressure regulating chamber chamber being in communication with an oblique hole channel of an upper sealing seat. The present invention provides an environmentally friendly, leak-free submersible motor protector that has the function of regulating the pressure balance inside and outside the chamber, preventing the motor from lacking oil, and is pollution-free.

Description

Technical Field

[0001] The invention belongs to the technical field of submersible electric pumps, and in particular relates to an environmentally friendly, leak-free submersible motor protector. Background Art

[0002] Existing technologies and defects:

[0003] Submersible electric pumps are used more and more widely in modern industry due to their small size and light weight. They can not only be used for oil extraction, but also for water well pumping, municipal water supply, and gas station pipeline oil transportation.

[0004] The main feature of traditional submersible electric pumps is that the electric pump unit submerges in the liquid medium to work. The liquid medium forms a certain flow rate after being sucked by the pump, flows through the surface of the motor to cool the motor, and can reduce the temperature of the motor surface. During the operation, the motor windings continue to heat up, the internal motor oil expands due to the heat, and the pressure increases. However, for the electric pump to operate stably, it is necessary to maintain the balance of internal and external pressures. The heated and expanded motor oil will flow to the protector and overflow into the liquid medium through the oil drain port on the upper part of the protector. This working mode has almost no effect on conventional oilfield production conditions, but for conditions with strict requirements on the cleanliness of the liquid medium, such as pure water extraction, this conventional submersible motor protector is not applicable.

[0005] On the other hand, in order to maintain the balance of internal and external pressures, the protector continuously overflows oil, which can easily cause a large amount of motor oil to be discharged. Especially in high-temperature well conditions, the operating temperature of the motor will be higher, and the internal motor oil will expand and overflow more at high temperatures, causing oil shortage inside the motor, and even burning the motor in severe cases.

[0006] The difficulty and significance of solving the above technical problems:

[0007] Therefore, based on these problems, it is of great practical significance to provide an environmentally friendly, leak-free submersible motor protector that can adjust the pressure balance inside and outside the cavity, prevent oil shortage inside the motor, and is pollution-free. Summary of the invention

[0008] The purpose of the present invention is to solve the technical problems existing in the known technology and provide an environmentally friendly, leak-free submersible oil motor protector that can adjust the pressure balance inside and outside the cavity to prevent oil shortage inside the motor and is pollution-free.

[0009] The technical solution adopted by the present invention to solve the technical problems existing in the known technology is:

[0010] An environmentally friendly, leak-free submersible motor protector comprises a pressure regulating chamber, the pressure regulating chamber comprises an inner pressure regulating chamber cavity and an outer pressure regulating chamber cavity, the inner pressure regulating chamber cavity is the internal space of a pressure regulating chamber capsule, the outer pressure regulating chamber cavity is the space between the pressure regulating chamber capsule and an outer shell, the inner pressure regulating chamber cavity is in communication with external well fluid, and the outer pressure regulating chamber cavity is in communication with an inclined hole channel of an upper sealing seat.

[0011] The protector provided by the present invention completely separates the external well fluid from the motor oil in the protector, and mainly relies on the contraction and expansion of the pressure regulating chamber capsule to adjust the pressure difference between the inside and outside of the motor. When the internal pressure of the motor is greater than the external pressure, the pressure regulating chamber capsule is compressed; when the internal pressure of the motor is less than the external pressure, the pressure regulating chamber capsule expands to achieve internal and external pressure balance. When this protector is used, the motor oil inside the protector will not overflow into the external environment, which has the advantages of environmental protection and no pollution, and is particularly suitable for clean media or occasions with strict requirements on working media.

[0012] The present invention can also adopt the following technical solutions:

[0013] In the above-mentioned environmentally friendly non-leakage submersible motor protector, further, the protector head is provided with a protector head annular liquid flow groove and a protector head "L"-shaped liquid flow channel, and the two are connected.

[0014] In the above-mentioned environmentally friendly, leak-free submersible motor protector, further, the shaft protection tube is provided with four shaft protection tube liquid holes at one end close to the protector head, which are respectively communicated with the protector head annular liquid groove on the protector head, and the inner cavity of the pressure regulating chamber is communicated with the outside world through the shaft protection tube liquid holes, the protector head annular liquid groove, and the protector head "L"-shaped liquid passage.

[0015] The "L"-shaped liquid passage of the protector head can be used to inject a certain volume of clean water into the inner cavity of the pressure regulating chamber, so that the pressure regulating chamber capsule is pre-expanded before oil injection and can occupy a certain pressure regulating space.

[0016] In the above-mentioned environmentally friendly, leak-free submersible motor protector, further, the bearing of the protector head is embedded in the inner hole of the protector head, and the two ends of the bearing are respectively isolated by the protector head mechanical seal and oil seal, and the bearing lubricating oil is separately injected from the protector head bearing oil filling hole and separated from the motor oil in the protector cavity.

[0017] Meet the lubrication requirements of the bearing and protector shaft during operation.

[0018] In the above-mentioned environmentally friendly non-leakage submersible motor protector, further, one end of the inner cavity of the pressure regulating chamber is mechanically sealed by an upper sealing seat.

[0019] Its function is to prevent the well fluid in the pressure regulating chamber from entering the protector settling chamber.

[0020] In the above-mentioned environmentally friendly leakage-free submersible motor protector, further, radial sealing grooves are provided at both ends of the shaft protection tube, and shaft protection tube O ring a and shaft protection tube O ring b are respectively installed in the radial sealing grooves to separate the outer cavity of the pressure regulating chamber from the external medium and the inner cavity of the pressure regulating chamber.

[0021] In the above-mentioned environmentally friendly non-leakage submersible motor protector, further, one end of the sedimentation chamber is communicated with the outer cavity of the pressure regulating cavity through the inclined hole channel of the upper sealing seat, and the other end is communicated with the thrust cavity through the inclined hole channel of the lower sealing seat.

[0022] In the above-mentioned environmentally friendly leakage-free submersible motor protector, further, the two ends of the protector are a protector head and a base, the protector head is connected to the pump suction port, the base is connected to the motor, a base oil passage is provided in the base, and a spring and a conical valve body are installed inside the base oil passage.

[0023] By replacing screw plugs of different lengths, the conical valve body can be opened or closed, thereby controlling the opening and closing of the oil passage.

[0024] In the above-mentioned environmentally friendly non-leakage submersible motor protector, further, two compensation tubes and a sedimentation shaft protection tube are provided inside the sedimentation chamber, and the two compensation tubes are recorded as an upper compensation tube and a lower compensation tube.

[0025] When the external well fluid enters the sedimentation chamber, due to the relatively large specific gravity of the well fluid, the well fluid will first be deposited at the lower part of the lower compensation tube. When the well fluid level is higher than the pipe mouth of the lower compensation tube, the well fluid will further enter the thrust chamber. The compensation tube has the effect of delaying the external medium from entering the motor when working.

[0026] In summary, the present invention has the following advantages and positive effects:

[0027] 1. The inner cavity of the pressure regulating chamber of the present invention is connected with the external well fluid through the protector head ring and the "L"-shaped liquid passage. The pressure difference between the inside and outside of the motor is mainly adjusted by the contraction and expansion of the pressure regulating chamber capsule. When the internal pressure of the motor is greater than the external pressure, the capsule in the protector is compressed; when the internal pressure of the motor is less than the external pressure, the capsule in the protector expands to achieve the purpose of overall pressure balance.

[0028] 2. When the protector of the present invention is running underground, it can not only provide motor oil for the motor, transmit torque, and bear the axial force of the pump like a conventional protector, but more importantly, it does not discharge motor oil to the external medium, does not cause environmental pollution, and has the advantages of environmental protection and no pollution. It is particularly suitable for occasions with clean media or strict requirements on working media.

[0029] 3. The protector provided by the present invention mainly relies on the contraction and expansion of the pressure regulating cavity capsule to achieve internal and external pressure balance, and the internal motor oil will not be lost, thereby avoiding the risk of motor oil overflow due to thermal expansion of the motor and a large amount of motor oil loss inside the protector, causing oil shortage in the motor and protector.

[0030] 4. The present invention improves the oil storage and discharge structure of the traditional capsule protector, changing the conventional structure of storing oil inside the capsule and storing liquid outside to a structure of storing oil outside the capsule and storing liquid inside. The motor oil has basically no discharge loss, and can replace the structure of capsules in parallel, greatly shortening the length of the protector and significantly reducing the cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The technical solution of the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments, but it should be understood that these drawings are designed only for explanation purposes and are not intended to limit the scope of the present invention. In addition, unless otherwise specified, these drawings are intended only to conceptually illustrate the structural configurations described herein and are not necessarily drawn to scale.

[0032] Figure 1 It is a structural diagram of an environmentally friendly, leak-free submersible motor protector;

[0033] Figure 2 This is a partial enlarged view of the structure of the protector pressure regulating chamber;

[0034] Figure 3 It is a cross-sectional schematic diagram of the screw hole position of the protector head;

[0035] Figure 4 This is a partial enlarged view of the liquid channel structure of the protector head.

[0036] Figure 5 A partial enlarged view of the base oil channel structure

[0037] In the figure:

[0038] 1-protector head; 2-housing; 3-shaft protection tube; 4-upper capsule seat; 5-capsule clamp; 6-pressure regulating chamber capsule; 7-lower capsule seat; 8-upper sealing seat; 9a-upper compensation tube; 9b-lower compensation tube; 10-settling shaft protection tube; 11a-protector head mechanical seal; 11b-upper sealing seat mechanical seal; 11c-lower sealing seat mechanical seal; 12-lower sealing seat; 13-upper thrust bearing; 14-slide plate; 15-lower Thrust bearing; 16 - base; 17 - protector shaft; 18 - oil filling valve; 19 - oil seal; 20 - bearing shell; 21a - vent hole plug; 22a - vent hole lead pad; 21b - water injection hole plug; 22b - water injection hole lead pad; 21c - bearing shell oil filling hole plug; 22c - bearing shell oil filling hole lead pad; 23 - shaft protection tube O ring a; 24 - shaft protection tube O ring b; 25 - lower capsule seat O ring; 26 - spring; 27 - conical valve body; 28 - plug.

[0039] A-thrust chamber; B-settling chamber; C-inner cavity of pressure regulating chamber; D-outer cavity of pressure regulating chamber; h-oil passage of base; m-oblique hole passage of lower sealing seat; n-oblique hole passage of upper sealing seat; k-fluid passage of shaft protection tube; r-"L" type fluid passage of protector head; s-annular fluid passage groove of protector head; u-oblique hole oil passage groove of protector head; v-oil filling hole of protector head bearing; p-water filling passage. DETAILED DESCRIPTION

[0040] The following is combined Figures 1 to 5 The present invention will be described in detail.

[0041] 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:

[0042] Embodiment 1:

[0043] The present invention discloses an environmentally friendly, leak-free submersible motor protector, wherein the upper end of the protector is connected to a pump, and the lower end is connected to a motor; the main structural parts of the protector include a protector head 1, a pressure regulating chamber (an inner chamber C of the pressure regulating chamber and an outer chamber D of the pressure regulating chamber), a sealing seat (an upper sealing seat 8 and a lower sealing seat 12), a sedimentation chamber B, a thrust chamber A, a protector shaft 17, a thrust bearing (an upper thrust bearing 13 and a lower thrust bearing 15) and a base 16.

[0044] The protector is mainly divided into four parts: a thrust chamber A, a settling chamber B, an inner chamber C of a pressure regulating chamber, and an outer chamber D of a pressure regulating chamber.

[0045] The thrust chamber A is provided with an upper thrust bearing 13, a slide plate 14 and a lower thrust bearing 15. The thrust chamber A is filled with motor oil and communicates with the motor through the base oil passage h. When the motor is working normally, the windings are heated, and the internal motor oil expands due to the heat, and enters the thrust chamber A through the base oil passage h set in the protector base 16. The motor oil continues to go up, and after encountering the lower seal seat mechanical seal 11c at the lower seal seat 12, the oil passage is cut off, and then flows to the sedimentation chamber B through the lower seal seat oblique hole passage m of the lower seal seat 12.

[0046] The sedimentation chamber B is composed of an upper seal seat 8, a lower seal seat 12, a housing 2, a protector shaft 17 and two mechanical seals, an upper seal seat mechanical seal 11b and a lower seal seat mechanical seal 11c, and is provided with an upper compensation tube 9a, a lower compensation tube 9b, and a sedimentation shaft protection tube 10 sleeved on the outside of the protector shaft 17. When the motor oil expanded by heat enters the sedimentation chamber B, the excess motor oil enters the upper seal seat oblique hole channel n of the upper seal seat 8 along the compensation tube 9a, and then enters the outer cavity D of the pressure regulating cavity.

[0047] The pressure regulating cavity outer cavity D is composed of a protector head 1, an outer shell 2, a shaft protection tube 3, an upper sealing seat 8 and a pressure regulating cavity capsule 6. The protector head 1, the sealing seat 8 and the outer shell 2 are connected by threads and radially sealed by O-rings. The shaft protection tube 3 is provided with radial sealing grooves at both ends, and the shaft protection tube O-ring a23 and the shaft protection tube O-ring b24 are respectively installed in the grooves to separate the pressure regulating cavity outer cavity D from the external medium and the pressure regulating cavity inner cavity C.

[0048] The inner cavity C of the pressure regulating cavity is formed by the pressure regulating cavity capsule 6, the shaft protection tube 3, the mechanical seal 11b, the shaft protection tube O-ring a23, the shaft protection tube O-ring b24, and the lower capsule seat O-ring 25. The two ends of the pressure regulating cavity capsule 6 are respectively sleeved in the upper capsule 4 and the lower capsule seat 7, and the capsule clamp 5 is used to firmly fix the pressure regulating cavity capsule 6 to the upper capsule seat 4 and the lower capsule seat 7. The shaft protection tube 3 is provided with a shaft protection tube liquid hole k on one side, and the protector head 1 is provided with a protector head annular liquid groove s and a protector head "L" type liquid passage r, and the protector head annular liquid groove s and the protector head "L" type liquid passage r intersect.

[0049] When the motor oil expands due to heat, it enters the outer cavity D of the pressure regulating cavity. As the pressure continues to increase, it will squeeze the outer wall of the pressure regulating cavity capsule 6, causing the volume of the pressure regulating cavity capsule 6 to shrink. The excess liquid in the inner cavity C of the pressure regulating cavity will pass through the shaft protection tube liquid hole k on the shaft protection tube 3, enter the protector head annular liquid groove s and the protector head "L" type liquid passage r, and finally be discharged to the outside to achieve the balance of pressure inside and outside the protector. On the contrary, when the motor stops, the temperature decreases, the motor oil shrinks, and the motor oil in the outer cavity of the pressure regulating cavity capsule 6 gradually moves downward and enters the lower end of the protector and the motor. The pressure of the outer cavity of the pressure regulating cavity capsule 6 will be lower than the external environmental pressure. The external well fluid will flow into the interior of the shaft protection tube through the protector head "L" type liquid passage r and the protector head annular liquid passage s, as well as the shaft protection tube liquid hole k, and finally flow to the inner cavity of the pressure regulating cavity capsule 6, causing the capsule to expand and adjust the pressure difference between the inside and outside to achieve pressure balance.

[0050] The protector head 1 is supported by a bearing 20, and the spaces on both sides of the bearing 20 are sealed by a mechanical seal 11a and an oil seal 19, respectively, to form a separate oil storage space isolated from the outside and the pressure regulating chamber C. The lubricating oil required for the bearing 20 is injected through the protector head bearing oil injection hole v. The axial position of the oil seal 19 is positioned and fixed by the end of the shaft protection tube 3.

[0051] Working principle: Before the protector is filled with oil, a certain volume of clean water needs to be injected into the pressure regulating inner cavity C, and the "L"-shaped liquid passage r port needs to be tightly blocked with the water injection hole screw plug 21b and the water injection hole lead pad 22b. The purpose of injecting clean water is to expand the inner cavity of the pressure regulating cavity capsule 6 and occupy the corresponding pressure regulating space in advance to prevent the oil pressure from crushing the pressure regulating cavity capsule 6 during oil injection and losing the pressure regulating space.

[0052] The oil is injected from the oil filling valve 18 on the base 16. The motor oil will gradually enter the thrust chamber A along the oil passage. When the thrust chamber A is filled, it will enter the sedimentation chamber B along the lower sealing seat oblique hole channel m of the lower sealing seat 12. When the motor oil fills the sedimentation chamber B, it will continue to enter the pressure regulating chamber outer chamber D along the upper sealing seat oblique hole channel n of the upper sealing seat 8 until the pressure regulating chamber outer chamber D is filled. Then, it enters the protector head oblique hole oil groove u, and opens the vent screw plug 21a. When the motor oil overflows from the screw mouth, it means that the protector is full of oil, and then tighten the vent screw plug 21a and the vent lead pad 22a. During the oil filling process, the pressure regulating chamber capsule 6 expands due to the advance water injection inside, leaving space for pressure regulation. Before installing the protector in the well, it is necessary to open the water injection hole screw plug 21b and the water injection hole lead pad 22b at the water injection hole to allow the inner cavity of the pressure regulating chamber capsule 6 to communicate with the external well fluid, ensuring that the pressure regulating chamber capsule 6 can shrink and expand under the action of the internal and external pressure difference to achieve the purpose of regulating pressure balance.

[0053] In summary, the present invention provides an environmentally friendly, non-leakage, submersible oil motor protector that can adjust the pressure balance inside and outside the cavity, prevent oil shortage inside the motor, and is pollution-free.

[0054] The above embodiments describe the present invention in detail, but the contents are only preferred embodiments of the present invention and cannot 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 present invention.

Claims

1. An environmentally friendly, leak-free submersible motor protector, characterized in that: The environmentally friendly non-leakage submersible motor protector comprises a pressure regulating chamber, the pressure regulating chamber comprises an inner pressure regulating chamber chamber and an outer pressure regulating chamber chamber, the inner pressure regulating chamber chamber is the internal space of the pressure regulating chamber capsule, the outer pressure regulating chamber chamber is the space between the pressure regulating chamber capsule and the outer shell, the inner pressure regulating chamber chamber is in communication with the external well fluid, and the outer pressure regulating chamber chamber is in communication with the inclined hole channel of the upper sealing seat; The two ends of the protector are a protector head and a base. The protector head is provided with a protector head annular liquid groove and a protector head "L"-shaped liquid passage, and the two are communicated with each other. The outer cavity of the pressure regulating cavity includes a shaft protection tube. The shaft protection tube is provided with four shaft protection tube liquid passage holes at one end close to the protector head, which are respectively communicated with the protector head annular liquid groove on the protector head. The inner cavity of the pressure regulating cavity is communicated with the outside world through the shaft protection tube liquid passage holes, the protector head annular liquid groove, and the protector head "L"-shaped liquid passage.

2. The environmentally friendly, leak-free submersible motor protector according to claim 1 is characterized by: The bearing shell of the protector head is embedded in the inner hole of the protector head, and the two ends of the bearing shell are isolated by the mechanical seal and oil seal of the protector head respectively. The bearing shell lubricating oil is separately injected from the bearing shell oil filling hole of the protector head and separated from the motor oil in the protector cavity.

3. The environmentally friendly, leak-free submersible motor protector according to claim 1 is characterized by: One end of the inner cavity of the pressure regulating cavity is mechanically sealed by an upper sealing seat.

4. The environmentally friendly, leak-free submersible motor protector according to claim 1 is characterized in that: The two ends of the shaft protection tube are provided with radial sealing grooves, in which the shaft protection tube O ring a and the shaft protection tube O ring b are respectively installed to separate the outer cavity of the pressure regulating cavity from the external medium and the inner cavity of the pressure regulating cavity.

5. The environmentally friendly, leak-free submersible motor protector according to claim 1 is characterized by: The environmentally friendly non-leakage submersible motor protector also includes a thrust chamber and a sedimentation chamber. One end of the sedimentation chamber is connected to the outer chamber of the pressure regulating chamber through the upper sealing seat inclined hole channel, and the other end is connected to the thrust chamber through the lower sealing seat inclined hole channel.

6. The environmentally friendly, leak-free submersible motor protector according to claim 1 is characterized by: The protector head is connected to the pump suction port, the base is connected to the motor, a base oil passage is opened in the base, and a spring and a conical valve body are installed inside the base oil passage.

7. The environmentally friendly, leak-free submersible motor protector according to claim 5 is characterized by: Two compensation pipes and a settlement shaft protection pipe are arranged inside the settlement chamber, and the two compensation pipes are marked as an upper compensation pipe and a lower compensation pipe.

Images