Wellhead sealer special for drainage and gas recovery of coal-bed gas well

Abstract

The utility model discloses a wellhead sealer special for drainage and gas recovery of a coal-bed gas well, which comprises a low-precision large-amplitude deviation adjusting device and a high-precision small-amplitude deviation adjusting device arranged at the upper end of the low-precision large-amplitude deviation adjusting device. A self-pressing sealing device is arranged at the upper end of the high-precision small-amplitude deviation adjusting device; and a lower packing is arranged between the high-precision small-amplitude deviation adjusting device and the low-precision large-amplitude deviation adjusting device. The device is simple in structure, convenient to operate and maintain, provided with a high-precision small-amplitude deviation adjusting device and a low-precision large-amplitude deviation adjusting device, capable of accurately controlling the angle of the polish rod, good in deviation preventing effect and capable of effectively reducing abrasion of the polish rod.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of well tool, specifically is a coalbed gas well drainage gas recovery special well mouth sealing ware. BACKGROUND

[0002] The coalbed gas well is opened to produce basically adopts beam type oil pumping unit, and the drainage gas recovery is carried out through the up and down movement of the polished rod driving sucker rod and oil pump; due to the large well inclination of the gas well, the gas anchor separation effect is poor, the well mouth liquid overflow has coalbed gas, especially the high yield, high casing pressure well, the gas is serious in the oil pipe, the conventional well mouth sealing ware cannot be sealed under pressure, and the water falls to the ground; the gas overflow pollutes the atmosphere, and the clean energy is wasted. It is particularly important to recycle the gas on site by using the collection equipment, and the commonly used well mouth sealing ware is adjustable well mouth sealing ware, which adopts rubber to realize well mouth sealing, adjusts the well mouth through two pairs of adjusting nuts, ensures that the polished rod is centered, slightly offsets and grinds, grinds the blowout box and polished rod, the rubber is easy to wear, the well mouth is easy to leak, and the sealing condition (> 0.2Mpa = gathering and transportation export pressure) cannot be reached, and the gas cannot be recycled.

[0003] The reason why the conventional well mouth cannot be sealed under pressure: the coalbed gas well is for drainage gas recovery, which is different from oil production, the polished rod is easy to corrode, and the water has no lubricating effect, and the rubber is easy to wear; in order to ensure the sealing property, the conventional sealing ware needs to fasten the blowout box regularly, the labor intensity is large, and the personnel inspection is not timely, which can cause the well mouth to be not sealed; the rubber used in the conventional sealing ware is polyurethane rubber, which is not resistant to corrosion and high temperature, and is easy to wear; the conventional sealing ware adjusts the well mouth through two pairs of adjusting nuts, and the adjustment range is small, and the polished rod cannot be accurately adjusted, and is easy to offset and grind.

[0004] Many new sealing wares are proposed by those skilled in the art.

[0005] The utility model discloses a kind of pumping unit well mouth grease injection polished rod sealing ware and special grease injection gun, including upper sealing and lubricating cabin, well shut-off valve, lower sealing cabin and offsetting assembly sequentially connected from top to bottom, the upper sealing and lubricating cabin is set grease injection hole, grease injection hole installs grease injection one-way valve nozzle, and grease injection one-way valve nozzle connects grease injection gun;The connection of the ball head of universal joint and spherical seat can realize axial offset, and the radial movement of offsetting pressure disc can realize the function of radial offset.

[0006] The utility model discloses a disc joint box seal blowout preventer for adjustable deviation of pumping unit well mouth discloses a disc joint box seal blowout preventer for adjustable deviation of pumping unit well mouth, including the disc joint box that has coaxial through hole from top to bottom, universal joint, well packer, deviation adjuster, connecting body that connect gradually, universal joint includes semicircle ball seat, ball and universal joint gland, and the part that is contacted in the lower part of ball crown's end of ball and semicircle ball seat is a groove respectively, and a plurality of limit steel balls are installed in the groove, so that the ball can swing in semicircle ball seat 360 DEG, and deviation adjuster includes upper flange plate, connecting cylinder and lower flange plate, and the inner wall of lower flange plate is provided with the righting block of cylinder, and the inner hole bottom of lower flange plate is provided with the sealing cover that elastically seals the inner hole of lower flange plate, and the center position on the upper surface of sealing cover is provided with a pulley.

[0007] The utility model discloses a multifunctional well mouth blocking and sealing device relates to petroleum machinery, and the inclination adjusting assembly of the device includes translational disc seat and universal ball seat, and the translational disc seat is connected and fixed with translational disc pressure cap through the thread of outer diameter surface, and the lower flange of universal ball seat is pressed and fixed between the both, and the sealing ring can guarantee the sealing between translational disc seat and universal ball seat after pressing. The neck and lower flange diameter of universal ball seat exist space between the corresponding parts of translational disc pressure cap, and this space can allow the plane movement of universal ball seat in the inner cavity of translational disc pressure cap before pressing, and the plane deviation adjusting range of the device is the movement range.

[0008] The above-mentioned prior art can only carry out one-level deviation adjustment, cannot carry out high-precision deviation adjustment, and has the problem of slight angle deviation and wear after deviation adjustment.

[0009] In summary, the technical solutions of the above-mentioned disclosed technologies and the technical problems to be solved and the beneficial effects produced are all different from those of the utility model, and the above-mentioned disclosed technology documents do not have technical inspiration for more technical features and the technical problems to be solved and the beneficial effects of the utility model. SUMMARY

[0010] In view of the above-mentioned defects existing in the prior art, the utility model aims at providing a well mouth sealer special for coalbed methane well drainage gas production.

[0011] In order to achieve the above-mentioned purpose, the utility model adopts the following technical scheme:

[0012] The utility model provides a well mouth sealer special for coalbed methane well drainage gas production, including low-precision large-amplitude deviation adjusting device, still including high-precision small-amplitude deviation adjusting device, the high-precision small-amplitude deviation adjusting device is set up in low-precision large-amplitude deviation adjusting device upper end, the high-precision small-amplitude deviation adjusting device upper end is provided with self-pressing seal sealing device, the high-precision small-amplitude deviation adjusting device, low-precision large-amplitude deviation adjusting device between setting lower packing.

[0013] Further, the high-precision small-amplitude biasing device comprises a sealing sleeve;

[0014] Specifically, the sealing sleeve is provided with at least three uniformly distributed righting sleeves, each of which is provided with a biasing rod group composed of a screw rod and a jacking rod.

[0015] Specifically, the screw rod is threadedly connected with the righting sleeve and can move forward and backward by rotation.

[0016] Specifically, the jacking rod penetrates through the righting sleeve and is inserted into the sealing sleeve, and a first sealing ring is arranged between the jacking rod and the sealing sleeve.

[0017] Further, the low-precision large-amplitude biasing device comprises a ball head packing seat and a lower joint.

[0018] Specifically, the ball head packing seat is provided with a ball head at the lower end, the lower joint is provided with a ball seat at the upper end, the ball head is seated in the ball seat, and a second sealing ring is arranged between the ball head and the ball seat.

[0019] Specifically, the ball head packing seat is provided with an upper ball seat at the upper end of the outer wall of the ball head, the upper ball seat is connected with an upper flange at the upper end, and the lower joint is threadedly connected with a lower flange at the outer wall.

[0020] Specifically, the upper flange and the lower flange are connected by at least two uniformly distributed biasing bolts.

[0021] Further, the self-pressing sealing device comprises a union cap and an upper packing.

[0022] Specifically, the inner wall of the sealing sleeve is provided with a first conical packing seat above the righting sleeve, and the upper packing is arranged in the first conical packing seat.

[0023] Specifically, the inner wall of the lower end of the union cap is threadedly connected with the outer wall of the upper end of the sealing sleeve, and a compression cover, a spring, and a lower spring seat are sequentially arranged inside the union cap from top to bottom.

[0024] Specifically, the spring is in a compressed state, and the spring always seats the upper packing in the first conical packing seat.

[0025] Further, the upper end of the sealing sleeve extends upward higher than the lower spring seat.

[0026] Further, the inner wall of the upper end of the ball head packing seat is provided with a second conical packing seat, and the inner wall of the sealing sleeve is provided with a compression ring below the righting sleeve.

[0027] Specifically, the lower packing is arranged in the second conical packing seat.

[0028] Specifically, the inner wall of the lower end of the sealing sleeve is threadedly connected with the outer wall of the upper end of the ball head packing seat, and the compression ring compresses the lower packing in the second conical packing seat.

[0029] Further, the sealing sleeve outer wall is provided with a first oil nozzle and a second oil nozzle.

[0030] Specifically, the first oil nozzle is in communication with the cap, and the space between the upper packing and the lower packing is in communication with the second oil nozzle.

[0031] Further, the top rod is a nylon rod, and the upper packing and the lower packing are made of oil polyethylene.

[0032] The utility model has the following beneficial effects compared with the prior art:

[0033] 1. The utility model has simple structure, convenient operation and easy maintenance, and has two-stage bias adjusting devices of high-precision small-amplitude bias adjusting device and low-precision large-amplitude bias adjusting device, can accurately control the angle of the polished rod, has good anti-bias effect and effectively reduces the wear of the polished rod.

[0034] 2. The utility model sets two-stage sealing packing and two-stage sealing oil cavity, has good sealing effect, reliable blowout prevention function and avoids safety accidents.

[0035] 3. In the utility model, the top rod in contact with the polished rod is a nylon rod, and the packing is made of oil polyethylene, which reduces the friction and energy consumption and prolongs the service life of the material.

[0036] 4. In the utility model, the spring always tightly seals the wellhead with the upper packing, so that the sealing device always tightly seals the wellhead during oil pumping. BRIEF DESCRIPTION OF DRAWINGS

[0037] Fig. 1 is the internal structure schematic view of the wellhead sealing device special for coalbed methane well drainage gas recovery of the utility model;

[0038] Fig. 2 is the external structure schematic view of the wellhead sealing device special for coalbed methane well drainage gas recovery of the utility model.

[0039] In the drawing: 1, cap; 2, gland; 3, sealing sleeve; 4, spring; 5, lower spring seat; 6, upper packing; 7, centralizing sleeve; 8, screw rod; 9, top rod; 10, lower packing; 11, second conical packing seat; 12, upper flange; 13, upper ball seat; 14, ball seat; 15, lower flange; 16, lower joint; 17, first oil nozzle; 18, second oil nozzle. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the utility model. Embodiments

[0041] Please refer to Figs. 1-2 The utility model provides a kind of wellhead seal for coalbed methane well drainage gas production, including high-precision small amplitude deviation adjusting device, low-precision large amplitude deviation adjusting device being sequentially arranged from top to bottom, the high-precision small amplitude deviation adjusting device upper end is provided with self-pressing sealing device, lower packing is arranged between the high-precision small amplitude deviation adjusting device, low-precision large amplitude deviation adjusting device.

[0042] The high-precision small amplitude deviation adjusting device includes sealing sleeve 3, the sealing sleeve periphery is provided with at least three uniform distribution's righting sleeve 7, deviation adjusting rod group consisting of screw rod 8, jack 9 is arranged in each righting sleeve 7, the screw rod 8 is in screw connection with righting sleeve 7, can be moved before and after screwing, the jack 9 passes through righting sleeve 7, inserts sealing sleeve 3, first sealing ring is arranged between the jack 9 and sealing sleeve 3.

[0043] Preferably, the jack 9 is nylon stick, reduces friction damage to polish rod, and is wear-resistant, and service life is long.

[0044] The low-precision large amplitude deviation adjusting device includes ball head packing seat, lower joint 16, the ball head packing seat lower end is provided with ball head, the lower joint 16 upper end is provided with ball seat 14, the ball head sits in ball seat 14, second sealing ring is arranged between the ball head and ball seat 14, the ball head packing seat ball head upper end outer wall is provided with upper ball seat 13, the upper ball seat 13 upper end is nested with upper flange 12, the lower joint 16 outer wall is in screw connection with lower flange 15, the upper flange 12 is connected with lower flange 15 by at least two uniform distribution's deviation adjusting bolt, the deviation angle of ball head packing seat is adjusted by adjusting the screwing amount of deviation adjusting bolt.

[0045] In use, the angle of ball head packing seat is adjusted by deviation adjusting bolt, and the precise deviation of polish rod is realized by adjusting the screwing amount of different screw rod 8 by spanner.

[0046] The self-pressing sealing device comprises a cap 1, an upper packing 6, a first tapered packing seat provided on the inner wall of the sealing sleeve 3 above the centralizing sleeve 7, the upper packing 6 being arranged in the first tapered packing seat, the inner wall of the lower end of the cap 1 being threadedly connected with the outer wall of the upper end of the sealing sleeve 3, the cap 1 internally having a grommet 2, a spring 4 and a lower spring seat 5 arranged in sequence from top to bottom, the spring 4 being in a compressed state, and the spring 4 keeping the upper packing 6 seated in the first tapered packing seat and tightly sealing the polished rod.

[0047] Specifically, the upper end of the sealing sleeve 3 extends upward higher than the lower spring seat 5, facilitating the installation of the spring 4.

[0048] The inner wall of the upper end of the ball head packing seat is provided with a second tapered packing seat 11, the inner wall of the sealing sleeve 3 is provided with a pressing ring below the centralizing sleeve 7, the lower packing is arranged in the second tapered packing seat 11, the inner wall of the lower end of the sealing sleeve 3 is threadedly connected with the outer wall of the upper end of the ball head packing seat, and the pressing ring presses the lower packing in the second tapered packing seat 11.

[0049] The outer wall of the sealing sleeve 3 is provided with a first oil nozzle 17 and a second oil nozzle 18, the first oil nozzle 17 is in communication with the cap 1, and the space between the upper packing 6 and the lower packing 10 is in communication with the second oil nozzle 18, so that the sealing grease is filled through the first oil nozzle 17 and the second oil nozzle 18.

[0050] The cap 1 plays a role of scraping the sealing grease on the polished rod and keeping the sealing grease in the cap 1.

[0051] Preferably, the upper packing 6 and the lower packing 10 are made of oil-based polyethylene, which has the advantages of strong hydrophobicity, easy lubrication and wear resistance. Embodiment

[0052] The embodiment provides a use method of the wellhead sealing device special for coalbed methane well drainage gas production, and specifically comprises the following steps.

[0053] The lower joint 16 of the low-precision large-amplitude bias adjusting device is connected with the wellhead, the lower packing 10 is arranged in the second tapered packing seat 11, the sealing sleeve 3 of the high-precision small-amplitude bias adjusting device is connected with the upper end of the ball head packing seat, and the pressing ring presses the lower packing 10.

[0054] The upper packing 6 is arranged in the first tapered packing seat, the lower spring seat 5 is placed on the first tapered packing seat, the spring 4 and the grommet 2 are placed in sequence, the cap 1 is sleeved outside the spring 4, the spring 4 is compressed downward, and the cap 1 is threadedly connected with the upper end of the sealing sleeve 3.

[0055] The liquid outlet connected with the wellhead needs to be higher than the wellhead sealing device special for coalbed methane well drainage gas production, so that the liquid under the lower packing 10 cannot be depressurized, and after the lower packing 10 is worn, the lower packing 10 can be pressed on the pressing ring by hydraulic pressure, so that the sealing effect is maintained.

[0056] Position all screws 8 of the high-precision, small-amplitude adjustment device to the outermost position, and lower the optical rod;

[0057] When replenishing the sealing grease, inject the sealing grease through the first grease nipple 17 and the second grease nipple 18;

[0058] During the adjustment, the position of the optical rod is first adjusted by adjusting the adjustment bolt 5 of the low-precision large-amplitude adjustment device, and then the position of the optical rod is finely adjusted by controlling the advance amount of different screws 8 in the high-precision small-amplitude adjustment device.

[0059] All components not discussed in detail in this application, as well as the connection methods of these components, are well-known technologies in this field. They can be directly applied and will not be elaborated further.

[0060] In this utility model, the term "multiple" refers to two or more unless otherwise explicitly defined. The terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0061] In the description of this utility model, it should be understood that the terms "upper", "lower", "left", "right", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or unit referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0062] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0063] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A special wellhead seal for drainage and gas production in coalbed methane wells, comprising a low-precision, large-amplitude adjustment device, characterized in that, It also includes a high-precision small-amplitude adjustment device, which is set at the upper end of the low-precision large-amplitude adjustment device; The high-precision small-amplitude deviation adjustment device is equipped with a self-pressure sealing device at its upper end. A lower packing ring is installed between the high-precision small-amplitude adjustment device and the low-precision large-amplitude adjustment device.

2. The wellhead seal for coalbed methane well drainage and gas production according to claim 1, characterized in that, The high-precision, small-amplitude adjustment device includes a sealing sleeve; The sealing sleeve is provided with at least three evenly distributed straightening sleeves around its perimeter, and each straightening sleeve is provided with an adjustment rod group consisting of a screw and a push rod; The screw is threadedly connected to the centering sleeve and can be screwed back and forth to move. The push rod passes through the straightening sleeve and is inserted into the sealing sleeve. A first sealing ring is provided between the push rod and the sealing sleeve.

3. A special wellhead seal for coalbed methane well drainage and gas production according to claim 2, characterized in that, The low-precision, large-amplitude adjustment device includes a ball head packing seat and a lower connector. The lower end of the ball head packing seat is provided with a ball head, the upper end of the lower connector is provided with a ball seat, the ball head sits in the ball seat, and a second sealing ring is provided between the ball head and the ball seat; The ball head packing seat has an upper ball seat on the outer wall of the upper end of the ball head, and an upper flange is connected to the upper end of the upper ball seat. The lower flange is threadedly connected to the outer wall of the lower connector. The upper flange and the lower flange are connected by at least two evenly distributed adjusting bolts.

4. A special wellhead seal for coalbed methane well drainage and gas production according to claim 3, characterized in that, The self-pressurized sealing device includes a cap and an upper packing. The inner wall of the sealing sleeve is provided with a first conical packing seat above the straightening sleeve, and the upper packing is disposed in the first conical packing seat; The inner wall of the lower end of the cap is threaded to the outer wall of the upper end of the sealing sleeve. The cap is provided with a pressure cap, a spring, and a lower spring seat from top to bottom. The spring is in a compressed state, and the spring keeps the upper packing root always seated in the first conical packing root seat.

5. A special wellhead seal for drainage and gas production in coalbed methane wells according to claim 4, characterized in that, The upper end of the sealing sleeve extends upwards above the lower spring seat.

6. A special wellhead seal for drainage and gas production in coalbed methane wells according to claim 4, characterized in that, The upper inner wall of the ball head packing seat is provided with a second conical packing seat, and the inner wall of the sealing sleeve is provided with a pressure ring below the straightening sleeve. The lower packing is disposed in the second conical packing seat; The lower inner wall of the sealing sleeve is connected to the upper outer wall of the ball head packing seat by threads, and the pressure ring presses the lower packing into the second conical packing seat.

7. A special wellhead seal for coalbed methane well drainage and gas production according to claim 4, characterized in that, The outer wall of the sealing sleeve is provided with a first oil nozzle and a second oil nozzle; The first nozzle is connected to the inner part of the cap, and the space between the upper packing and the lower packing is connected to the second nozzle.

8. A special wellhead seal for coalbed methane well drainage and gas production according to claim 4, characterized in that, The top rod is a nylon rod, and the upper and lower packings are made of oil-based polyethylene.

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