CN111520084A - Special joint with sealing and connecting structure - Google Patents

Abstract

The invention discloses a special joint with a sealing and connecting structure, which relates to the technical field of hot fluid and petroleum collection and conveying equipment, and comprises: install the interior installation department, sealed face, the outer installation department on the joint main part, the joint protection body of pipeline lower extreme, have on the interior installation department be used for with the internal thread of pipeline lower extreme lug connection, have on the outer installation department be used for with the external screw thread of pipeline coupling. The invention can be used for solving the problems of sealing and connecting when the 'inner heat-insulating pipe' is used in the process of collecting hot fluid, so that the size precision, the roughness and the like of the joint main body are easy to master, the joint main body is convenient to replace and repair even if the problems exist, and the oil pipe and the core pipe can be well connected and sealed under the conditions of length change caused by expansion and contraction and possible angular displacement between an upper coupling and a lower coupling during the fastening operation of the oil pipe in scenes such as oil field sites and the like.

Description

A special joint with sealing and connecting structure

technical field

The invention relates to the technical field of thermal fluid and oil collection and conveying equipment, in particular to a special joint with a sealing and connecting structure for connecting pipes.

Background technique

The commonly used traditional oil production method is rod pumping, that is, steel tubing is connected by connecting rods, and steel sucker rods are used in the tubing to connect the oil pump at the bottom of the well. In addition to the ground base temperature, the initial liquid temperature of a 2000-meter oil well is generally 60-80 °C.

Through the up-and-down movement of the sucker rod, the downhole liquid is lifted to the ground. During this process, due to the heat dissipation effect of the steel pipe, the temperature of the liquid in the pipe gradually decreases, and the wax in the liquid gradually precipitates, which will affect the oil well performance to a certain extent. Normal discharge. In order to prevent wax precipitation and wax removal in oil wells, measures such as sucker rod heating, oil well hot cleaning, and chemical addition are required, which require energy consumption, consumables, time-consuming, labor-consuming and cost-intensive.

In order to solve the problem of wax formation in the oil pipe, people are constantly exploring, one of the methods is to make an insulation layer (called "internal insulation pipe") in the oil pipe to increase the temperature of the liquid in the pipe, thereby slowing down or even avoiding the wax formation in the oil pipe. Similarly, in the process of collecting and transporting various thermal fluids, such as underground hot water, geothermal steam and heat-carrying gas, which are stored in the ground and whose temperature is higher than normal, it is also necessary to adopt the same insulation layer structure in the pipeline to improve the internal temperature of the pipeline. The temperature of the fluid, in order to make the inner insulation oil pipe can be used repeatedly and facilitate maintenance, after the small-diameter core pipe is put into the conventional oil pipe, its two ends must be sealed and can be disassembled, and the sealing structure is generally located at both ends of the oil pipe or at the joint. In the process of realizing the present invention, the inventor found that there are at least the following problems in the sealing of the end of the core pipe in the prior art: First, the joint connection method of the pipe will change after the "internal thermal insulation pipe" is adopted, and the operator will The joint is not suitable and needs to be retrained; secondly, due to the problem of pipe processing accuracy, especially when using old oil pipes, the size, surface flatness and roughness are difficult to control, so the sealing effect will be greatly affected; the traditional joint is shown in the figure 2, it can be seen from its structure that the traditional coupling and coupling method do not have the function of completely sealing and connecting the inner core tube. The length change caused by cold shrinkage and the angular displacement between the upper and lower couplings may occur during the tightening operation of the tubing in the oil field, which will also have a negative impact on the sealing effect. Therefore, new ideas are needed to solve the above problems.

SUMMARY OF THE INVENTION

The main purpose of the present invention is to provide a special joint with a sealing and connecting structure, so as to solve the sealing and connection problems when an "internal insulation pipe" is used in the process of collecting thermal fluid.

In order to achieve the above purpose, the present invention provides a special joint with a sealing and connecting structure, which is used for the connection of pipes used in the thermal fluid collection process and the sealing of the inner core pipe. The special joint has:

a joint body installed at the lower end of the pipe, the joint body is cylindrical and has a through hole;

an inner installation part, the inner installation part is arranged inside the joint body, and the inner installation part has an inner thread for directly connecting with the lower end of the pipe;

a sealing surface, the sealing surface is provided on the side of the inner mounting portion inside the joint body, the sealing surface extends to the end face inside the joint body; and

an outer mounting part provided on the outside of the joint body, the outer mounting part extends to the end face on the same side as the sealing surface on the joint body, and the outer mounting part has an external thread for coupling with the pipe .

Further, the length of the outer mounting portion is smaller than the length of the sealing surface.

Further, the material of the joint body is made of metal material with steel grade of J55, K55, N80, L80 or P110.

Further, the outer diameter of the joint body adopts a size range of 30mm-300mm, and the inner diameter of the joint body adopts a size range of 25mm-250mm.

Further, the wall thickness of the joint body adopts a size range of 5 mm to 50 mm.

The beneficial effects of adopting the above-mentioned technical solutions of the present invention are:

(1) The connection method of general pipelines is retained;

(2) On the basis of traditional couplings and pipes, this joint is designed and installed at the lower part of the pipe, mainly to seal the end of the core pipe;

(3) Since the special joint of the present invention, the inner core tube and the joint covered with the thermal insulation layer are assembled in the factory, the oil well operation method still maintains the original operation method after the assembly arrives at the oilfield site, ensuring that the Quality of construction on site.

(4) The sealing of the inner core tube can be carried out in the oil pipe or in the coupling and joint. The method of sealing in the oil pipe is convenient for processing, so that the special joint can be used not only for the transformation and connection of the old oil pipe, but also for the connection of the newly designed oil pipe. Surface flatness and roughness are difficult to control, so the sealing effect will be greatly affected. The special joint of the embodiment of the present invention is sealed in the joint body, so the dimensional accuracy and roughness of the joint body are easy to control, and even if there is a problem, it is very convenient to replace and repair; In the case of the resulting length change and the possible angular displacement between the upper and lower couplings during the tightening operation of the tubing in the oil field and other scenes, the pipeline and core tube can still be well connected and sealed.

Description of drawings

1 is a schematic cross-sectional view of an embodiment of the present invention;

Figure 2 is a schematic half-section view of a conventional joint.

In the accompanying drawings, the list of components represented by each number is as follows:

1-joint body; 2-inner mounting part; 3-sealing surface; 4-outer mounting part.

Detailed ways

It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terms used herein in the description of the present invention are for the purpose of describing specific embodiments only, and are not intended to limit the present invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments These are some embodiments of the present invention, but not all embodiments.

As shown in FIG. 1 , an embodiment of the present invention provides a special joint with a sealing and connecting structure. The special joint is used for the connection of pipes used in the thermal fluid collection process and the sealing of the inner core pipe. The special joint is particularly Installed on the lower end of the pipe, the joint includes: a joint main body 1 installed on the lower end of the pipeline, the joint main body 1 is a cylindrical structure and has a through hole, the inside of the through hole of the joint main body 1 is a segmented design, and the inside of the joint main body 1 starts from a An inner mounting part 2 and a sealing surface 3 are provided from one side to the other. The inner mounting part 2 has an internal thread for direct connection with the lower end of the pipe, and the sealing surface 3 is provided on one side of the inner mounting part 2 and extends to the joint The inner end face of the main body 1; the outer side of the joint main body 1 is provided with an outer mounting portion 4, the outer mounting portion 4 extends to the end face on the same side as the upper sealing surface 3 of the joint main body 1, and the outer mounting portion 4 is provided with a pipe coupling of the external thread.

Through the implementation of the above embodiments, a special joint with a sealing and connecting structure according to the embodiment of the present invention can be installed at the lower end of the downhole tubing, wherein the inner thread in the inner mounting portion 2 is directly connected to the tubing, and the structure and size of the inner thread The parameters of the general oil pipe coupling can be referred to. The external thread in the outer mounting part 4 is connected with the oil pipe coupling. The parameters of the external thread structure and size can also refer to the general oil pipe parameters. Through the structure setting of the sealing surface 3 of this special joint, the The conventional sealing structure is directly arranged on the special joint, and at the same time, the sealing surface 3 extends to the end face inside the joint body 1, which can more conveniently and efficiently improve the sealing performance of the oil pipe connection. In the case of the possible angular displacement between the upper and lower couplings during the tightening operation of the oil pipe and the oil pipe, the oil pipe and the core pipe can still be well connected and sealed.

In the above-mentioned embodiment, in order to better connect the oil pipe to the pipe, the pipe to the core pipe, and to make the pipe assembly more convenient in the process of processing and assembling, the outer mounting portion 4 extends to the joint body 1 and seals it. The end face on the same side of the face 3, and at the same time, the length of the outer mounting portion 4 is smaller than the length of the sealing face 3.

In the embodiment of the present invention, the material of the joint body 1 can be made of all allowed metal materials in the current standard, and the steel grades can be J55, K55, N80, L80, P110, etc.

In addition, in the embodiment provided by the present invention, the outer diameter of the joint body 1 can be in the range of 30mm to 300mm, and the inner diameter of the joint body 1 can be in the range of 25mm to 250mm, wherein the wall thickness of the joint main body 1 adopts The size ranges from 5mm to 50mm. Therefore, the basic size of the special joint in the embodiment of the present invention can adopt the size in the current standard, and the length is designed according to the small diameter steel pipe, or specially designed and manufactured according to the user's requirements. standard to design. The special joint retains the connection method of the general joint, so that the special joint can be used not only for the transformation and connection of the old oil pipe, but also for the connection of the newly designed oil pipe, so as to avoid the problem of pipe processing accuracy, especially when using the old oil pipe. It is difficult to control the surface flatness and roughness, so that the sealing effect will be greatly affected. With the special joint of the embodiment of the present invention, the joint body 1 is sealed, so the dimensional accuracy and roughness of the joint body 1 are easy to control, and even if there is a problem, it is convenient to replace and repair.

In the first embodiment provided by the present invention, a special joint with sealing and connecting structure, the special joint has a joint main body 1, the joint main body 1 is cylindrical and has a through hole, and the outer diameter of the coupling main body 1 is 141.3mm, the remaining dimensions can use the dimensions in the current standard.

In the second embodiment provided by the present invention, a special joint with sealing and connecting structure, the special joint has a joint main body 1, the joint main body 1 is cylindrical and has a through hole, and the outer diameter of the coupling main body 1 is 73mm, the other dimensions can adopt the dimensions in the current standard.

Through the application of the above embodiments, a special joint with sealing and connecting structure of the present invention has the following advantages:

(1) The connection method of general pipelines is retained;

(2) On the basis of traditional couplings and pipes, this joint is designed and installed at the lower part of the pipe, mainly to seal the end of the core pipe;

(3) Since the special joint of the present invention, the inner core tube and the joint covered with the thermal insulation layer are assembled in the factory, the oil well operation method still maintains the original operation method after the assembly arrives at the oilfield site, ensuring that the Quality of construction on site.

(4) The sealing of the inner core tube can be carried out in the oil pipe or in the coupling and joint. The method of sealing in the oil pipe is convenient for processing, so that the special joint can be used not only for the transformation and connection of the old oil pipe, but also for the connection of the newly designed oil pipe. Surface flatness and roughness are difficult to control, so the sealing effect will be greatly affected. With the special joint of the embodiment of the present invention, the joint body 1 is sealed, so the dimensional accuracy and roughness of the joint body 1 are easy to control, and even if there is a problem, it is convenient to replace and repair.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features thereof can be equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the embodiments of the present invention. scope.

Claims (5)

1. a special joint with sealing and connecting structure, used for the connection of the pipeline used in the thermal fluid collection process and the sealing of the inner core pipe, it is characterized in that, this special joint has: a joint body installed at the lower end of the pipe, the joint body is cylindrical and has a through hole; an inner installation part, the inner installation part is arranged inside the joint body, and the inner installation part has an inner thread for directly connecting with the lower end of the pipe; a sealing surface, the sealing surface is provided on the side of the inner mounting portion inside the joint body, the sealing surface extends to the end face inside the joint body; and an outer mounting part provided on the outside of the joint body, the outer mounting part extends to the end face on the same side as the sealing surface on the joint body, and the outer mounting part has an external thread for coupling with the pipe . 2 . The special joint with sealing and connecting structure according to claim 1 , wherein the length of the outer mounting portion is smaller than the length of the sealing surface. 3 . 3 . The special joint with sealing and connecting structure according to claim 1 , wherein the material of the joint body is made of metal material with steel grade of J55, K55, N80, L80 or P110. 4 . 4. A special joint with sealing and connection structure according to any one of claims 1-3, characterized in that: the outer diameter of the joint body adopts a size range of 30mm-300mm, and the inner diameter of the joint body is in the range of 30mm to 300mm. The size range used is 25mm ~ 250mm. 5 . The special joint with sealing and connecting structure according to claim 4 , wherein the wall thickness of the joint main body adopts a size range of 5 mm to 50 mm. 6 .

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