Anti-eccentric-wear double-helix hydraulic pre-tightening packing device

Abstract

The utility model belongs to the technical field of oil pumping unit polish rod sealing in oil field oil exploitation equipment, and discloses an anti-eccentric-wear double-helix hydraulic pre-tightening packing device which comprises a packing box, a sealing assembly is detachably installed in the packing box, and a gland is detachably installed on the upper end face of the sealing assembly. A plurality of cooling fins are fixedly installed on the outer surface of the packing box, the sealing assembly comprises a connecting cover detachably installed at the upper end of the packing box, a first spiral blade is fixedly installed on the end face, close to the interior of the packing box, of the connecting cover, and a second spiral blade is connected to the spiral surface of one side of the first spiral blade in an abutting mode; a packing is connected to the spiral surface of the other side of the first spiral blade in an abutting mode, a pressure hose is connected between the second spiral blade and the packing in an abutting mode, and the first spiral blade, the second spiral blade, the packing and the pressure hose are consistent in spiral direction. The packing is simple in overall structure, the service life of the packing can be prolonged, packing leakage is reduced, and the using effect is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of reciprocating seals in oilfield petroleum production equipment, and specifically relates to an anti-eccentric wear double-helix hydraulic pre-tightening packing device. Background Art

[0002] In oil production, the smooth rod seal at the wellhead of the oil well is an important link to ensure the safe production of the oil well and environmental protection. The smooth rod seal at the wellhead of the oil well can prevent oil and gas leakage, extend the service life of the equipment, and prevent environmental pollution.

[0003] In the prior art, the sealing of the oil wellhead polished rod mainly depends on the wellhead packing box and the sealing elements inside it. Through reasonable installation and maintenance, the polished rod is tightly sealed to prevent the leakage of the fluid in the well.

[0004] During oilfield exploitation, the sealing effect between the wellhead polished rod and the sealing packing directly affects the safe production and environmental protection of the oil well. However, in actual operation, due to the complex conditions of the pumping wells, misalignment between the polished rod and the wellhead often occurs, which makes the polished rod susceptible to eccentric wear during use. This not only shortens the service life of the polished rod, but also increases maintenance costs and the risk of oil and gas leakage. At the same time, it accelerates the wear of the packing, reduces the sealing effect, and requires frequent replacement to ensure the normal production of the oil well. This not only increases the labor intensity of the operator, but also increases the maintenance cost of the oil well. In addition, when the polished rod is in operation for a long time, high temperature and high pressure will occur, causing oil well leakage and affecting production operations.

[0005] When the packing sealing effect is not good, oil and gas are likely to leak out from the gap between the bare rod and the packing, which not only pollutes the environment, but may also cause safety accidents such as fire, causing economic losses and negative impacts to the company.

[0006] At present, the domestic pumping unit bare rod sealing technology generally improves the sealing effect by changing the shape of the packing, or by adding a mechanism to adjust the packing and making structural improvements in the packing cavity. Although there is a certain effect, it is difficult to meet the needs of dynamic sealing.

[0007] A Chinese patent with application number 201821355676.2 discloses a packing adding device, which belongs to the field of oil production auxiliary process technology. The device includes: a scraper gland, a scraper, a top cylinder, an oil storage box, an oil filling hole plug, a packing box tongue, a packing box gland and a packing box; the utility model embodiment quickly adds packing to the packing box by rotating the top cylinder, and completes the addition of packing without stopping the pumping unit. The operation is simple and time-saving, which improves the speed of replacing packing and ensures the production efficiency of the oil well.

[0008] However, the utility model does not completely solve the problem of easy wear of the packing. When the packing is not replaced in time, there is still a risk of oil and gas leakage. Utility Model Content

[0009] The main technical problem to be solved by the utility model is to provide a sealing device with a simple overall structure, which can adapt to complex working conditions and has functions such as straightening, lubrication, self-adjustment and heat dissipation. Solutions are proposed in terms of polished rod centering, packing wear compensation, self-lubrication and packing friction heat dissipation, so as to extend the service life of the packing, reduce packing leakage and improve the sealing reliability of the anti-eccentric wear double-helix hydraulic pre-tightening packing device.

[0010] In order to solve the above technical problems, the utility model provides the following technical solutions:

[0011] A double-helix hydraulic pre-tightening packing device for preventing eccentric wear comprises a packing box, a sealing assembly is detachably installed inside the packing box, a pressure cover is detachably installed on the upper end surface of the sealing assembly, a plurality of heat dissipation fins are fixedly installed on the outer surface of the packing box, the sealing assembly comprises a connecting cover detachably installed at the upper end position of the packing box, a first spiral blade is fixedly installed on the end surface of the connecting cover close to the inside of the packing box, a second spiral blade is connected to the top of the spiral surface on one side of the first spiral blade, a packing is connected to the top of the spiral surface on the other side of the first spiral blade, a pressure hose is connected between the second spiral blade and the packing, and the spiral directions of the first spiral blade, the second spiral blade, the packing and the pressure hose are consistent.

[0012] The following is a further optimization of the above technical solution by the utility model:

[0013] A sealing cavity is provided in the middle of the packing box, and the sealing assembly is located in the sealing cavity;

[0014] A lubrication cavity is provided inside the packing box near the inner wall;

[0015] A liquid outlet is provided on the outer wall of the packing box near the gland position, and a liquid inlet is provided on the outer wall of the packing box away from the gland position.

[0016] Further optimization: the outer surface of the packing box is also connected with a pipe assembly.

[0017] Further optimization: the pipe assembly includes a liquid inlet pipe connected to the liquid inlet, the liquid inlet pipe is connected to the lubrication cavity, and a one-way valve is connected to the liquid inlet pipe;

[0018] The liquid outlet is connected with a liquid outlet pipe, the liquid outlet pipe is connected with the lubrication chamber, and the liquid outlet pipe is connected with a pressure regulating valve;

[0019] A connecting pipe is fixedly installed at a position of the packing box close to the connecting cover, one end of the connecting pipe is connected to the lubrication cavity, and the other end of the connecting pipe is connected to the pressure hose.

[0020] Further optimization: a plurality of lubrication holes in a circular array are provided on the inner wall of the sealing cavity near the middle position.

[0021] Further optimization: a polished rod hole is arranged in the middle of the sealing component.

[0022] The utility model adopts the above technical scheme, has ingenious conception and reasonable structure, can play the role of straightening, lubricating, self-adjusting and heat dissipating the polished rod in the polished rod seal of the oil wellhead, avoids the phenomenon of eccentric wear of the polished rod and serious wear of the packing, prolongs the service life of the packing, reduces the labor intensity of the staff, can improve the production efficiency, is safe and reliable, is easy to operate, and has a simple overall structure, is convenient to manufacture and produce, can reduce the production and use costs, and improve economic benefits.

[0023] The utility model provides a first spiral blade and a second spiral blade, which respectively form a plurality of independent sealing spaces with the top-connected packing. When one sealing space fails, the other sealing spaces can still maintain the sealing effect, thereby increasing the service life of the sealing component and facilitating use.

[0024] At the same time, the first spiral blade and the second spiral blade make the polished rod hole rigid and play a certain role in straightening the polished rod. The lubricating medium penetrates into the sealing component from the lubrication hole to lubricate the polished rod and reduce the wear of the polished rod.

[0025] In addition, heat dissipation fins are arranged on the outer surface of the packing box to dissipate the heat generated by the friction of the packing, further improving the service life of the packing.

[0026] The utility model is further described below in conjunction with the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a cross-sectional view of the overall structure in the embodiment of the utility model;

[0028] Figure 2 This is a schematic diagram of the internal structure of the packing box in the embodiment of the utility model;

[0029] Figure 3 It is a schematic structural diagram of the sealing assembly in an embodiment of the utility model.

[0030] In the figure: 1-packing box; 11-sealing chamber; 12-liquid inlet; 13-liquid outlet; 14-lubricating hole; 15-lubricating chamber; 2-pressure cover; 3-heat dissipation fin; 4-pipe assembly; 41-liquid outlet pipe; 42-pressure regulating valve; 43-liquid inlet pipe; 44-check valve; 45-connecting pipe; 5-sealing assembly; 51-packing; 52-first spiral blade; 53-pressure hose; 54-bare rod hole; 55-connecting cover; 56-second spiral blade; 6-lubricating medium. DETAILED DESCRIPTION

[0031] like Figure 1-3 As shown: an anti-eccentric wear double-helix hydraulic pre-tightening packing device includes a packing box 1, a sealing assembly 5 is detachably installed inside the packing box 1, a pressure cover 2 is detachably installed on the upper end surface of the sealing assembly 5, a plurality of heat dissipation fins 3 are fixedly installed on the outer surface of the packing box 1, the sealing assembly 5 includes a connecting cover 55 detachably installed at the upper end position of the packing box 1, a first spiral blade 52 is fixedly installed on the end surface of the connecting cover 55 close to the inside of the packing box 1, a second spiral blade 56 is connected to the spiral surface of one side of the first spiral blade 52, a packing 51 is connected to the spiral surface of the other side of the first spiral blade 52, a pressure hose 53 is connected between the second spiral blade 56 and the packing 51, and the spiral directions of the first spiral blade 52, the second spiral blade 56, the packing 51 and the pressure hose 53 are consistent.

[0032] A sealing cavity 11 is opened in the middle of the packing box 1 , and the sealing assembly 5 is located in the sealing cavity 11 .

[0033] A lubrication cavity 15 is provided inside the packing box 1 near the inner wall.

[0034] A liquid outlet 13 is provided on the outer wall of the packing box 1 near the gland 2 .

[0035] A liquid inlet 12 is provided on the outer wall of the packing box 1 at a position away from the gland 2 .

[0036] The outer surface of the packing box 1 is also connected with a pipe assembly 4.

[0037] The pipe assembly 4 includes a liquid inlet pipe 43 connected to the liquid inlet port 12 , and the liquid inlet pipe 43 is connected to the lubrication cavity 15 .

[0038] The liquid inlet pipe 43 is connected to a one-way valve 44 .

[0039] The other end of the liquid inlet pipe 43 is connected to the high-pressure end of the wellhead high-pressure manifold, and the liquid in the wellhead high-pressure manifold flows into the sealing cavity 11 through the one-way valve 44 and the liquid inlet 12 .

[0040] In this embodiment, the liquid in the wellhead high-pressure manifold is the lubricating medium 6 .

[0041] The function of the one-way valve 44 is to ensure that the lubricating medium 6 in the wellhead high-pressure manifold can only flow toward the liquid inlet 12 and cannot flow back.

[0042] The liquid outlet 13 is connected to a liquid outlet pipe 41 , which is then connected to the lubrication chamber 15 . The liquid outlet pipe 41 is connected to a pressure regulating valve 42 .

[0043] The other end of the liquid outlet pipe 41 is connected to the low-pressure end of the wellhead high-pressure manifold.

[0044] With this design, the lubricating medium 6 in the wellhead high-pressure manifold flows into the lubricating cavity 15 via the one-way valve 44 and the liquid inlet 12 . At this time, the pressure regulating valve 42 is closed to allow the lubricating medium 6 to fill the lubricating cavity 15 .

[0045] A connecting pipe 45 is fixedly installed at a position of the packing box 1 close to the connecting cover 55 . One end of the connecting pipe 45 is connected to the lubrication chamber 15 , and the other end of the connecting pipe 45 is connected to the pressure hose 53 .

[0046] When the lubricating chamber 15 is filled with the lubricating medium 6 , the lubricating medium 6 continues to flow into the pressure hose 53 through the connecting pipe 45 .

[0047] When the pressure hose 53 is filled with the lubricating medium 6, the volume of the pressure hose 53 increases, causing the packing 51 to be tightened; when the pressure regulating valve 42 is opened, the lubricating medium 6 flows out of the liquid outlet 13, flows into the low-pressure end of the wellhead high-pressure manifold through the liquid outlet pipe 41 and the pressure regulating valve 42, and at this time, the lubricating medium 6 in the pressure hose 53 flows back into the lubrication cavity 15, and the volume of the pressure hose 53 decreases, causing the packing 51 to become loose.

[0048] Therefore, the pressure hose 53 functions to adjust the tightness of the packing 51 .

[0049] A plurality of lubrication holes 14 in a circular array are provided on the inner wall of the sealing cavity 11 near the middle.

[0050] With this design, when the lubrication cavity 15 is filled with the lubrication medium 6 , the lubrication medium 6 penetrates into the sealing cavity 11 through the lubrication hole 14 , and then penetrates into the packing 51 of the sealing assembly 5 , thereby ensuring the lubrication and sealing effect of the packing 51 .

[0051] A polished rod hole 54 is arranged in the middle of the sealing assembly 5 , and the polished rod of the oil pumping unit moves up and down in the polished rod hole 54 .

[0052] The outer surface of the connecting cover 55 at the end close to the sealing cavity 11 is provided with a first thread, and the packing box 1 is also provided with a second thread matching the first thread on the connecting cover 55 at a position corresponding to the connecting cover 55 .

[0053] The connection cover 55 is detachably installed by the cooperation of the first thread and the second thread.

[0054] At the same time, when the first thread of the connecting cover 55 is screwed in the direction close to the packing box 1, the first spiral blade 52 is driven to rotate in the spiral direction, so that the first spiral blade 52 is tightened. The first spiral blade 52, the second spiral blade 56, the packing 51 and the pressure hose 53 have the same spiral direction. When the first spiral blade 52 is tightened, the second spiral blade 56, the packing 51 and the pressure hose 53 are tightened at the same time.

[0055] When the first thread of the connecting cover 55 is rotated away from the packing box 1, the first spiral blade 52 is driven to rotate in the opposite direction of the spiral direction, thereby loosening the first spiral blade 52. The first spiral blade 52, the second spiral blade 56, the packing 51 and the pressure hose 53 have the same spiral direction. When the first spiral blade 52 is loosened, the second spiral blade 56, the packing 51 and the pressure hose 53 are loosened at the same time.

[0056] This enables further manual adjustment of the packing tightness.

[0057] In this embodiment, the first spiral blade 52 and the second spiral blade 56 are made of stainless steel. This design makes the polished rod hole 54 rigid, and when the polished rod slides up and down in the polished rod hole 54, it is not easy to have eccentric wear.

[0058] At the same time, the first spiral blade 52 and the second spiral blade 56 respectively form a plurality of independent sealing spaces with the top-connected packing. When one sealing space fails, the other sealing spaces can still maintain the sealing effect, thereby increasing the service life of the sealing assembly 5.

[0059] In addition to this embodiment, the first spiral blade 52 and the second spiral blade 56 can be combined and replaced by a rectangular spring, which can also achieve the effect of adjusting the tightness.

[0060] The heat dissipation fins 3 dissipate the heat generated by the packing 51 during operation. The heat dissipation principle of the heat dissipation fins 3 is well known and widely used in the prior art, and will not be described in detail here.

[0061] The installation and disassembly method of the gland 2 is a well-known technology in the commonly used packing box seal. The gland 2 is detachably installed by bolts, which facilitates the replacement of the sealing assembly 5 and will not be described in detail here.

[0062] In addition to this embodiment, the existing design scheme is also applicable to the plunger seal of reciprocating pump equipment, thereby increasing the scope of application.

[0063] For ordinary technicians in this field, according to the teachings of the present invention, without departing from the principles and spirit of the present invention, changes, modifications, substitutions and deformations made to the implementation methods are still within the protection scope of the present invention.

Claims

1. An anti-eccentric wear double-helix hydraulic pre-tightening packing device, comprising a packing box (1), a sealing assembly (5) being detachably mounted inside the packing box (1), and a gland (2) being detachably mounted on the upper end surface of the sealing assembly (5), characterized in that: The outer surface of the packing box (1) is fixedly mounted with a plurality of heat dissipation fins (3); the sealing assembly (5) comprises a connection cover (55) detachably mounted at the upper end of the packing box (1); a first spiral blade (52) is fixedly mounted on the end surface of the connection cover (55) close to the interior of the packing box (1); a second spiral blade (56) is top-connected to a spiral surface on one side of the first spiral blade (52); a packing (51) is top-connected to a spiral surface on the other side of the first spiral blade (52); a pressure hose (53) is top-connected between the second spiral blade (56) and the packing (51); and the spiral directions of the first spiral blade (52), the second spiral blade (56), the packing (51) and the pressure hose (53) are consistent.

2. The anti-eccentric wear double-helix hydraulic pre-tightening packing device according to claim 1 is characterized by: A sealing cavity (11) is provided at a middle position inside the packing box (1), and the sealing assembly (5) is located in the sealing cavity (11); A lubrication cavity (15) is provided inside the packing box (1) near the inner wall; A liquid outlet (13) is provided on the outer wall of the packing box (1) at a position close to the gland (2), and a liquid inlet (12) is provided on the outer wall of the packing box (1) at a position away from the gland (2).

3. The anti-eccentric wear double-helix hydraulic pre-tightening packing device according to claim 2 is characterized by: The outer surface of the packing box (1) is also connected to a pipe assembly (4).

4. The anti-eccentric wear double-helix hydraulic pre-tightening packing device according to claim 3 is characterized by: The pipe assembly (4) comprises a liquid inlet pipe (43) connected to the liquid inlet port (12), the liquid inlet pipe (43) being connected to the lubrication chamber (15), and a one-way valve (44) being connected to the liquid inlet pipe (43); The liquid outlet (13) is connected to a liquid outlet pipe (41), the liquid outlet pipe (41) is connected to the lubrication chamber (15), and the liquid outlet pipe (41) is connected to a pressure regulating valve (42); A connecting pipe (45) is fixedly installed at a position of the packing box (1) close to the connecting cover (55); one end of the connecting pipe (45) is connected to the lubrication chamber (15), and the other end of the connecting pipe (45) is connected to the pressure hose (53).

5. The anti-eccentric wear double-helix hydraulic pre-tightening packing device according to claim 2 is characterized by: A plurality of lubrication holes (14) in a circular array are provided on the inner wall of the sealing cavity (11) near the middle.

6. The anti-eccentric wear double-helix hydraulic pre-tightening packing device according to claim 1 is characterized by: A polished rod hole (54) is arranged in the middle of the sealing assembly (5).

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