CN204783586U - Latent oily linear electric motor's sealing system - Google Patents

Abstract

A sealing system for an oil submersible linear motor, the sealing system is arranged around the upper pull rod and the lower rod at both ends of the oil submersible linear motor, so that the upper pull rod and the lower rod are in a dynamically sealed lubricating oil environment, and the sealing system includes an upper corrugated tube and the lower bellows, the upper end of the upper bellows is provided with an upper liquid storage bag connected with it, the upper end of the lower bellows is provided with a lower liquid storage bag connected with it, the upper bellows and the lower bellows are respectively composed of several segmented corrugated Tubes are vertically spliced, and any adjacent segmented bellows are connected by connecting flanges. Each segmental bellows is also provided with a limit pin. The upper liquid storage bag and the lower liquid storage bag of the utility model play a compensating role. , to compensate the extrusion force of the crude oil in the oil well on the upper bellows and the lower bellows, the limit pin is used to limit the extension or contraction stroke of the segmented bellows, and the corresponding segmented bellows in the upper or lower pump barrel The distance traveled vertically.

Description

A sealing system for submersible linear motor

technical field

The utility model relates to a sealing system of a submersible linear motor, which is a device system for realizing dynamic sealing of a submersible linear motor, and belongs to the technical field of underground oil production equipment.

Background technique

The traditional oil pumping equipment is mainly beam pumping unit-oil pumping device. The whole set of equipment is divided into surface and underground. Due to the complex and changeable oil well mining conditions, with the continuous increase of well depth and production, this kind of pumping unit is heavy and heavy. The shortcomings of many accidents and low displacement have become very obvious. The disadvantages of traditional oil production equipment are (1) eccentric wear: it is difficult for the sucker rod to always keep parallel to the axis of the tubing during the up and down reciprocating motion, especially for inclined wells, which often break due to eccentric wear, and even cause the pump barrel to wear out (2) High loss: most of the main power of the pumping unit is consumed in the mechanical transmission, and the power directly used to pump oil is very small, and the general useful work is only 20%--30%; (3) It is heavy and takes up Large area: the quality of the pumping unit is large, consumes a lot of steel, and occupies a large area; (4) It is easy to cause pump jamming: when the beam pumping unit extracts oil, the dust in the oil can only go to the upper end of the plunger pump (5) Not suitable for poor oil wells: when encountering poor oil wells, the plunger of the oil well pump runs without load, causing dry grinding of the plug cylinder, which not only wastes resources, but also easily It causes the annealing and softening of the plug cylinder after dry grinding; (6) High maintenance cost: the traditional pumping unit is bulky, cumbersome to maintain and high in cost.

The submersible linear motor is placed under the oil well to directly drive the oil pump to reciprocate oil pumping, forming a set of high-efficiency linear motor rodless pumping technology, and now this technology has been well applied to replace traditional oil pumping equipment, but When the current existing linear motor is working under the oil well, the lubricating oil around the mover and the tie rod will leak or the well fluid is directly used for the lubrication of the mover. The well fluid containing water, salt, sand and other impurities in the well fluid will enter the inner cavity of the stator and the tube, causing serious surface wear of the mover and tie rods during the operation process, severe corrosion of the magnetic steel, and even fracture. Due to downhole operations, The maintenance is complicated and the cost is high.

After searching, the utility model finds that the patent number is 201410726053.1, and the patent name is a sealing device for an electric submersible reciprocating pump oil production system. This patent discloses a sealing device for an electric submersible reciprocating pump oil production system, including electric The pump barrel of the submersible reciprocating pump, the pull rod of the oil well pump, and the linear motor are also included. The upper and lower ends of the linear motor are sealed and surrounded by the upper bellows and the lower bellows respectively. The bellows protection tube adopts high elasticity and corrosion-resistant rubber bellows, which realizes the complete isolation of the moving part of the submersible linear motor from the well fluid. The trouble-free working time of the electric submersible reciprocating pump oil recovery system is guaranteed. However, in this patent, the utility model did not take into account the actual working environment of the electric submersible reciprocating pump. The submersible linear motor pump set needs to work in an oil well with a depth of one thousand meters or even five kilometers. The height of the dynamic liquid level is uncertain, and the height of the dynamic liquid level of the same well is constantly changing from pumping to normal oil pumping, so the pressure of the well fluid on the entire submersible linear motor will also vary with the dynamic fluid pressure. The surface height is different or changes constantly, and the sealing system made of bellows will deform with the change of pressure because it cannot be compensated, and cannot maintain the best running state; while the rubber bellows is in the If its shape is not guaranteed, the continuous compression and elongation will quickly fail, resulting in the failure of the entire sealing system. On the other hand, during the movement of the mover, the lubricating oil in the upper bellows and the lower bellows needs to be exchanged continuously through the air gap formed between the inner cavity of the stator and the mover. Because the lubricating oil has a certain viscosity, it will periodically The pressure changes in the upper bellows and the lower bellows permanently, and the pressure will cause non-free deformation of the bellows, resulting in a sharp decline in the life of the bellows or even a failure to achieve normal expansion and contraction at all. Therefore this patent can't really be applied in the oil well operation production.

Utility model content

In order to solve the above-mentioned existing problems, the utility model discloses a sealing system of a submersible linear motor, and the specific technical scheme is as follows:

A sealing system for a submersible linear motor, the sealing system is arranged around the upper rod and the lower rod at both ends of the submersible linear motor, so that the upper rod, the mover and the lower rod are in a completely sealed lubricating oil environment,

The oil submersible linear motor includes a stator and a mover. The mover reciprocates linearly inside the stator. The upper and lower rods are respectively installed and fixed at both ends of the mover. The two ends of the oil submersible linear motor are respectively An upper connecting pipe and a lower connecting pipe are provided, and the upper and lower rods are driven to reciprocate in the upper connecting pipe and the lower connecting pipe by the mover;

The top of the upper connecting pipe is provided with an oil pump, the bottom of the lower connecting pipe is provided with a plug, and several breathing holes are evenly distributed on the surrounding surfaces of the upper connecting pipe and the lower connecting pipe;

The sealing system includes an upper bellows, a lower bellows, an upper liquid storage bag and a lower liquid storage bag,

The upper liquid storage bag is arranged at one end of the upper bellows close to the oil-submersible linear motor, the upper liquid storage bag and the upper bellows are sealed and connected, and the interior is interconnected, and the upper liquid storage bag and the upper bellows are filled with lubricating oil , the upper tie rod is arranged on the axial center line of the upper bellows and the upper liquid storage bag, the top of the upper tie rod is provided with an upper tie rod connection seat, the lower end of the upper tie rod connection seat is sealed with the upper bellows, and the upper end Connect the oil pump through the oil pump connecting rod;

The lower liquid storage bag is arranged at one end of the lower bellows close to the oil-submersible linear motor, and the lower liquid storage bag and the lower bellows are sealed and connected to each other, and the lower liquid storage bag and the lower bellows are filled with lubricating oil. The lower rod and the lower liquid storage bag are arranged on the axial center line of the lower bellows, and the lower end of the lower bellows is sealed with a bottom flange;

One end of the upper liquid storage bag and the lower liquid storage bag close to the submersible linear motor is respectively sealed and fixed by the sealing flange and the stator;

The elastic deformation coefficient of the upper liquid storage bag is smaller than that of the upper bellows, and the elastic deformation coefficient of the lower liquid storage bag is smaller than that of the lower bellows.

The upper bellows and the lower bellows are respectively composed of several segmented bellows axially spliced, and any adjacent segmental bellows are connected by bellows connecting flanges.

Each segmented bellows is provided with a limit pin for limiting the axial telescoping stroke of the segmented bellows and the axial travel distance of the corresponding segmented bellows on the upper connecting pipe or the lower connecting pipe.

The limit pin includes waist-shaped grooves arranged on the walls of the upper connecting pipe and the lower connecting pipe, and the bellows connecting flange is provided with pins that are buckled in the waist-shaped grooves. When the bellows connecting flange moves up and down , the pin moves up and down in the waist-shaped groove following the connecting flange of the bellows, and the length of the waist-shaped groove is the displacement stroke allowed by the corresponding segmented bellows.

The limit pin includes a hard strut and a chain, one end of the hard strut is fixed to the bellows connection flange, the other end is connected to one end of the chain, and the other end of the chain is connected to the adjacent bellows Flange connection.

The working principle of the utility model is:

When the oil submersible linear motor equipped with the sealing system of the utility model is put into the oil well for operation, the oil submersible linear motor penetrates into the crude oil below the oil well, and the well fluid enters the upper connecting pipe and the breathing holes around the lower connecting pipe into the upper oil well. In the connecting pipe and the lower connecting pipe, the outer surfaces of the upper bellows and the lower bellows are filled with well fluid, and the well fluid has an inward extrusion effect on the upper bellows, lower bellows, upper liquid storage bag, and lower liquid storage bag. At the same time, Since the elastic coefficient of the upper liquid storage bag and the lower liquid storage bag is smaller than that of the upper bellows and the lower bellows, the liquid storage bag is first compressed to increase the lubricating oil pressure inside the sealing system until the lubricating oil pressure is the same as that of the external well. The hydraulic pressure is equal, so that the pressure on the inside and outside of the upper bellows and the lower bellows reaches a balanced state, the shape of the upper bellows and the lower bellows is well maintained, and the compression and stretching of the bellows can be minimized when the mover moves. Natural expansion and contraction under deformation and minimum stress state.

After the submersible linear motor runs, the mover reciprocates axially in the stator, and the mover drives the upper and lower rods to reciprocate; when the mover moves downward, the lower rod moves downward, and the lower bellows begins to elongate, and the inner bellows begin to elongate. The volume of the cavity becomes larger. At this time, the filling of lubricating oil comes from two aspects. On the one hand, the lubricating oil in the upper bellows and the upper liquid storage bag flows into the lower bellows through the gap between the mover and the stator; It is the replenishment of lubricating oil in the lower liquid storage bag; due to the timely replenishment of the lower liquid storage bag, the internal and external pressure difference of the lower bellows hardly exists, and the lower bellows stretches freely. At this time, the upper bellows is in the compression process as the mover moves down, and the lubricating oil inside the bellows will go to two places. On the one hand, the lubricating oil is stored in the upper liquid storage bag; due to the timely absorption of the upper liquid storage bag, the internal and external pressure difference of the upper bellows hardly exists, and the upper bellows shrinks freely. When the mover moves upward, the process is reversed to the above process, and the upper and lower bellows can still expand and compress freely under the minimum pressure difference.

The beneficial effects of the utility model are:

1. The upper liquid storage bag and the lower liquid storage bag play a compensating role. The depth of the well fluid inserted into the oil well by the utility model is different, and the pressure of the well fluid is different around the upper corrugated pipe and the lower corrugated pipe; the utility model is inserted into the crude oil in the oil well When the depths are different, the upper and lower reservoirs first deform accordingly, so that the upper bellows and the lower bellows will not be deformed due to the difference in the pressure of the surrounding well fluid;

2. The upper liquid storage bag and the lower liquid storage bag can replenish or absorb the pressure difference caused by the volume change when the upper bellows and the lower bellows are stretched or compressed in time when the mover moves, so that the bellows can operate under a smaller differential pressure. Under elongation or compression, the life of the bellows is maximized;

3. Both the upper bellows and the lower bellows are set into several segmented bellows. Since the upper bellows and the lower bellows are very long, the very long upper bellows and lower bellows are inserted into the crude oil of the oil well, and the upper bellows The extrusion force of crude oil at different heights of the lower bellows is different, resulting in the unsegmented upper bellows and lower bellows being deformed when they are not working. During the movement of the upper or lower rods, the upper and lower The deformation of the bellows and the lower bellows is uneven, which may easily cause damage to the upper bellows or the lower bellows, or even fail to work normally. The segmented bellows have a certain deformation range. When the length of the lower rod changes, each segmented bellows can be deformed within its own deformation range. The upper bellows and the lower bellows can not only maintain a vertical position relationship, but also maintain a stable deformation to achieve a stable working effect. Has a long service life;

4. The limit pin can limit any adjacent segmented bellows to maintain axial docking, and limit the movement stroke of each segmented bellows. In actual work, each segmented bellows will have appropriate deformation and movement journey.

Description of drawings

Fig. 1 is a structural representation of the utility model,

Figure 2 is a partial enlarged view of A in Figure 1,

Fig. 3 is a partial enlarged view of B in Fig. 1,

Fig. 4 is a partial enlarged view of C in Fig. 1,

Fig. 5 is a partial enlarged view of D in Fig. 1,

Fig. 6 is a partial enlarged view of E in Fig. 1,

Fig. 7 is a partial enlarged view of F in Fig. 1,

List of reference signs: 1—oil pump, 2—oil pump connecting rod, 3—upper tie rod connecting seat, 4—upper connecting pipe, 5—upper bellows, 6—bellows connecting flange, 7—limiting pin, 8— Upper tie rod, 9—connecting flange, 10—upper liquid storage bag, 11—sealing flange, 12—stator, 13—mover, 14—lower liquid storage bag, 15—lower rod, 16—bottom flange, 17 - the lower connecting pipe, 18 - plug, 19 - the lower bellows.

Detailed ways

Below in conjunction with accompanying drawing and specific embodiment, further illustrate the utility model. It should be understood that the following specific embodiments are only used to illustrate the utility model but not to limit the scope of the utility model.

The submersible linear motor comprises a stator 12 and a mover 13. The mover 13 reciprocates linearly inside the stator 12. The two ends of the mover 13 are respectively provided with an upper connecting pipe 4 and a lower connecting pipe 17. The upper connecting pipe 4 The upper and lower connecting pipes 17 are respectively provided with an upper pull rod 8 and a lower rod 15, and the two ends of the upper pull rod 8 and the lower rod 15 are fixed with the mover 13. When the submersible linear motor is working, the upper pull rod 8 and the lower rod 15 follow the movement. Child 13 reciprocates in upper connecting pipe 4 and lower connecting pipe 17 together, realizes work.

Fig. 1 is a structural representation of the utility model, as can be seen from the figure, the lower connecting pipe 17 of the present utility model is symmetrically arranged on the two ends of the submersible linear motor with the upper connecting pipe 4, and the sealing system of the submersible linear motor includes an upper corrugation The pipe 5 and the lower bellows 19, the upper pull rod 8 and the lower pull rod 15 are arranged on the axial centerlines of the upper bellows 5 and the lower bellows 19 respectively.

The utility model relates to a sealing system for an oil-submersible linear motor. The sealing system is arranged around the upper rod 8 and the lower rod 15 at both ends of the oil-submersible linear motor, so as to realize the complete sealing of the upper rod 8, the mover 13 and the lower rod 15. In an oil environment, the oil submersible linear motor includes a stator 12 and a mover 13, the mover 13 reciprocates linearly inside the stator 12, and the upper pull rod 8 and the lower pull rod 15 are installed and fixed on both ends of the mover 13 respectively , the two ends of the submersible linear motor are respectively provided with an upper connecting pipe 4 and a lower connecting pipe 17, and the upper pull rod 8 and the lower connecting rod 15 are driven by the mover 13 to reciprocate in the upper connecting pipe 4 and the lower connecting pipe 17; The top of the upper connecting pipe 4 is provided with an oil pump 1, the bottom of the lower connecting pipe 17 is provided with a plug 18, and several breathing holes are evenly distributed on the surface around the upper connecting pipe 4 and the lower connecting pipe 17; After the new type is inserted into the oil well, the well fluid in the oil well flows into the upper connecting pipe 4 and the lower connecting pipe 17 through the breathing hole, the upper bellows 5, the lower bellows 19, the upper liquid storage bag 10 and the lower liquid storage bag 14 The outside is surrounded by well fluid.

2, FIG. 3, FIG. 4, FIG. 5, FIG. 6 and the partial enlarged view of the utility model in FIG. A liquid bag 14, the upper liquid storage bag 10 is axially arranged at the lower end of the upper bellows 5, the upper liquid storage bag 10 is sealed butted with the upper bellows 5, and the inside communicates with each other, and the upper liquid storage bag 10 and the upper The bellows 5 is filled with lubricating oil, the upper tie rod 8 is arranged on the axial center line of the upper bellows 5 and the upper liquid storage bag 10, the top of the upper tie rod 8 is provided with an upper tie rod connecting seat 3, and the upper tie rod 8 is provided with an upper tie rod connecting seat 3. The lower end of the tie rod connection seat 3 is sealed with the upper bellows 5, and the upper end is connected to the oil pump 1 through the oil pump connecting rod 2; The tubes 19 are sealed butted and connected internally, the lower liquid storage bag 14 and the lower bellows 19 are filled with lubricating oil, the lower rod 15 and the lower liquid storage bag 14 are arranged on the axial center line of the lower bellows 19, so The lower end of the lower bellows 19 is sealed with a bottom flange 16; the ends of the upper liquid storage bag 10 and the lower liquid storage bag 14 close to the submersible linear motor are respectively sealed and fixed by the sealing flange 11 and the stator 12; the upper liquid storage A complete dynamic sealing system of lubricating oil is formed inside the bag 10 and the upper bellows 5, and a complete sealing system of lubricating oil is also formed inside the lower liquid storage bag 14 and the lower bellows 19. During work, when the upper pull rod 8 or the lower rod 15 moves, the lubricating oil will not leak in the corresponding dynamic sealing system, and extraneous substances will not enter the lubricating oil complete sealing system. When the upper tie rod 8 or the lower rod 15 moves, the upper bellows 5 and the lower bellows 19 deform themselves to meet the change of the lubricating oil sealing system occupied by the upper tie rod 8 or the lower rod 15 .

The elastic deformation coefficient of the upper liquid storage bag 10 is smaller than that of the upper bellows 5 , and the elastic deformation coefficient of the lower liquid storage bag 14 is smaller than that of the lower bellows 19 . The utility model is placed in the oil well, the upper liquid storage bag 10 can be deformed earlier than the upper bellows 5, and the lower liquid storage bag 14 can be deformed earlier than the lower bellows 19, so that the deformation of the upper bellows 5 and the lower bellows 19 can be achieved. stable control.

The upper bellows 5 and the lower bellows 19 are composed of several segmented bellows axially spliced respectively, and any adjacent segmented bellows are connected by bellows connecting flanges 6 . The segmented bellows can effectively prevent the local deformation of the upper bellows 5 or the lower bellows 19 from being uneven.

Each segmented bellows is provided with a limit pin 7 for limiting the stretching or shrinking stroke of the segmented bellows and the axial travel distance of the corresponding segmented bellows on the upper connecting pipe 4 or the lower connecting pipe 17 .

As a specific embodiment of the limit pin 7: the limit pin 7 includes a waist-shaped groove arranged on the pipe wall of the upper connecting pipe 4 and the lower connecting pipe 17, and the bellows connecting flange 6 is provided with a buckle in the waist-shaped groove When the bellows connecting flange 6 moves up and down, the pin follows the bellows connecting flange 6 and moves up and down in the waist-shaped groove, and the length of the waist-shaped groove is the displacement allowed by the corresponding segmented bellows journey.

As another specific embodiment of the limit pin 7: the limit pin 7 includes a hard strut and a chain, one end of the hard strut is fixed to the bellows connecting flange 6, and the other end is connected to one end of the chain, so The other end of the chain is connected to the bellows connecting flange 6 adjacent to it. When the segmented bellows moves to the maximum allowable stroke, the chain will pull the adjacent segmented bellows and will not continue to deform and elongate. When the segmented bellows deforms and shortens, the allowed shortest shortening deformation is the adjacent The segmented bellows above interfere with the stiff struts. After the segmental corrugation reaches the maximum allowable deformation range, the inside of the upper bellows 5 or the lower bellows 19 has not reached the force balance, and other segmental bellows will be deformed, so as to avoid the deformation transition of the segmental bellows and affect the service life.

The technical means disclosed in the solution of the utility model are not limited to the technical means disclosed in the above technical means, but also include technical solutions composed of any combination of the above technical features.

Claims (5)

1. A sealing system of a submersible linear motor, the sealing system is arranged around the upper rod and the lower rod at both ends of the submersible linear motor, so that the upper rod, the mover and the lower rod are in a completely sealed lubricating oil environment, The oil submersible linear motor includes a stator and a mover. The mover reciprocates linearly inside the stator. The upper and lower rods are respectively installed and fixed at both ends of the mover. The two ends of the oil submersible linear motor are respectively An upper connecting pipe and a lower connecting pipe are provided, and the upper and lower rods are driven to reciprocate in the upper connecting pipe and the lower connecting pipe by the mover; The top of the upper connecting pipe is provided with an oil pump, the bottom of the lower connecting pipe is provided with a plug, and several breathing holes are evenly distributed on the surrounding surfaces of the upper connecting pipe and the lower connecting pipe; It is characterized in that the sealing system includes an upper bellows, a lower bellows, an upper liquid storage bag and a lower liquid storage bag, The upper liquid storage bag is arranged at one end of the upper bellows close to the oil-submersible linear motor, the upper liquid storage bag and the upper bellows are sealed and connected to each other, and the upper liquid storage bag and the upper bellows are filled with lubricating oil , the upper tie rod is arranged on the axial center line of the upper bellows and the upper liquid storage bag, the top of the upper tie rod is provided with an upper tie rod connection seat, the lower end of the upper tie rod connection seat is sealed with the upper bellows, and the upper end Connect the oil pump through the oil pump connecting rod; The lower liquid storage bag is arranged at one end of the lower bellows close to the oil-submersible linear motor, the lower liquid storage bag is sealed butted with the lower bellows and interconnected internally, the lower liquid storage bag and the lower bellows are filled with lubricating oil, The lower rod and the lower liquid storage bag are arranged on the axial center line of the lower bellows, and the lower end of the lower bellows is sealed with a bottom flange; One end of the upper liquid storage bag and the lower liquid storage bag close to the submersible linear motor is respectively sealed and fixed by the sealing flange and the stator; The elastic deformation coefficient of the upper liquid storage bag is smaller than that of the upper bellows, and the elastic deformation coefficient of the lower liquid storage bag is smaller than that of the lower bellows. 2. The sealing system of a kind of submersible linear motor according to claim 1, characterized in that the upper bellows and the lower bellows are respectively composed of several segmented bellows axially spliced, and any adjacent segment The bellows are connected by bellows connecting flanges. 3. The sealing system of a submersible linear motor according to claim 2, characterized in that each segmented bellows is provided with a stroke for limiting the axial expansion and contraction of the segmented bellows and a corresponding segmented bellows The limit pin for the axial travel distance of the upper connecting pipe or the lower connecting pipe. 4. The sealing system of a kind of submersible linear motor according to claim 3, characterized in that said limit pin includes waist-shaped grooves arranged on the walls of the upper connecting pipe and the lower connecting pipe, and the connecting flange of the bellows is arranged There are pins buckled in the waist-shaped groove. When the bellows connecting flange moves up and down, the pin moves up and down in the waist-shaped groove following the bellows connecting flange. The length of the waist-shaped groove is the corresponding segment The displacement stroke allowed by the bellows. 5. The sealing system of a kind of submersible linear motor according to claim 3, wherein the limit pin comprises a hard strut and a chain, one end of the hard strut is fixed to the bellows connection flange, and the other One end is connected to one end of the chain, and the other end of the chain is connected to a bellows connecting flange adjacent to it.