Metal pipe and PE pipe connecting structure and preassembled metal valve

Abstract

The utility model discloses a metal pipe and PE pipe connecting structure which comprises a sleeve and a PE pipe, one end of the sleeve is provided with an external thread, one end of the PE pipe is provided with an internal thread, the sleeve is in threaded connection with the PE pipe, the sleeve is connected with a sleeve, the sleeve and the sleeve form an annular connecting groove, and the PE pipe is connected with the annular connecting groove. The thickness of a gap of the connecting groove is smaller than the wall thickness of the PE pipe, the gap of the connecting groove is in interference fit with the wall thickness of the PE pipe, the width of the sleeve is larger than the length of threads of the sleeve and the PE pipe, and the sleeve and the sleeve are both made of metal materials and fixedly connected in an annular welding mode. The technology is applied to the metal valve, equivalently, a section of PE pipe is preassembled at each of the two ends of the metal valve, when the metal valve is connected with other PE pipes on site, only the PE pipes and other pipelines need to be connected with a machine shell in a hot melting mode through a hot melting connector, operation is more convenient, and working efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of valve production, in particular to a connecting structure between a metal pipe and a PE pipe and a pre-installed metal valve. Background Technique

[0002] Valves are an important part of industrial pipelines and are one of the key products for controlling the safe operation of the entire pipe network. Generally, valves are used in conjunction with pipelines. The pipelines are made of plastic or metal. The earliest pipeline material was metal pipelines. With the popularization of plastic materials and the transportation of some media that can corrode metal pipelines, plastic pipelines are often used. When connecting a PE pipeline and a metal valve, traditional connection structures often have leakage at the connection. When the transported medium is gas, the leakage cannot be detected in time. When the transported medium is some harmful substances, there will be certain safety hazards. For example, in the field of gas transportation, on the one hand, gas components will cause certain corrosion to metal pipelines, and metal pipelines in long-term use need to be replaced in time. On the other hand, if gas leakage is not detected in time, there will be great safety hazards. At the same time, it is more troublesome to connect the valve and the pipeline at the construction site. Therefore, a metal valve that can be quickly connected to a PE pipeline on site is needed to improve the construction efficiency on site. Content of the Utility Model

[0003] (I) Technical Solution

[0004] In order to solve the above technical problems, the utility model provides a connecting structure between a metal pipe and a PE pipe and a pre-installed metal valve.

[0005] The specific technical solution is as follows:

[0006] A connecting structure between a metal pipe and a PE pipe includes a sleeve and a PE pipe. One end of the sleeve is provided with an external thread, and one end of the PE pipe is provided with an internal thread. The sleeve and the PE pipe are in threaded connection. A sleeve is connected to the sleeve, and an annular connection groove is formed between the sleeve and the sleeve. The thickness of the gap of the connection groove is less than the wall thickness of the PE pipe, which is an interference fit. The width of the sleeve is greater than the threaded lengths of the sleeve and the PE pipe. The sleeve and the sleeve are both made of metal and are fixedly connected by circumferential welding.

[0007] Further, the bottom of the annular connection groove formed by the sleeve and the sleeve is a threadless part, and the outer diameter of this part is greater than the outer diameter of the external thread part of the sleeve.

[0008] Further, an annular groove is provided at the threadless part at the bottom of the annular connection groove formed by the sleeve and the sleeve, and an O-ring is correspondingly provided in the annular groove.

[0009] Further, the number of O-rings is at least 1.

[0010] Furthermore, an anti - detachment groove is provided at the bottom of the annular connection groove formed by the sleeve and the casing. The thickness of the anti - detachment groove is greater than the thickness of the annular connection groove formed by the sleeve and the casing.

[0011] Furthermore, fine threads are also provided on the inner wall of the casing.

[0012] Based on the same inventive concept, the present utility model also proposes a pre - installed metal valve, which includes a valve body. Sleeves are connected to both sides of the valve body, and a PE pipe is connected to the sleeves. The connection structure between the sleeve and the PE pipe adopts any one of the above - mentioned connection structures between the metal pipe and the PE pipe, and the sleeve and the valve body are connected by circumferential welding.

[0013] (II) Beneficial effects

[0014] Compared with the prior art, the technical solution proposed by the present utility model has the following advantages: First, the PE pipe and the metal sleeve are thread - connected, then the casing is pressed tightly at the thread connection to form an interference fit, and the casing and the sleeve are welded. The connection structure formed in this way has better sealing performance, and at the same time, it can effectively prevent the PE pipe and the sleeve from being pulled off, ensuring the connection strength. Applying this technology to the metal valve is equivalent to pre - installing a section of PE pipe at both ends of the metal valve. When connecting with other PE pipes on - site, only a hot - melt connector is needed to perform hot - melt connection between the PE pipe and other pipelines, which is more convenient to operate and improves work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model, the following will briefly introduce the drawings required for use in the embodiments or the prior art descriptions. Obviously, the following - described drawings are only some embodiments of the present utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0016] Figure 1 It is a schematic structural diagram of the present utility model;

[0017] Figure 2 It is a schematic structural diagram of the pre - installed valve DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] The following will clearly and completely describe the technical solutions in the embodiments of the present utility model with reference to the drawings in the embodiments of the utility model. The described embodiments are only a part of the embodiments of the utility model, rather than all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the utility model.

[0019] In the related prior art, the connection sealing performance and connection strength between metal pipes and PE pipes are limited, and phenomena such as pulling-off and leakage may occur. Specifically, when connecting a metal valve and a PE pipe, leakage may occur at the connection, and at the same time, the connection operation efficiency of the metal valve and the PE pipe on-site is relatively low.

[0020] To solve the problems existing in the related prior art, the present utility model proposes a connection structure between a metal pipe and a PE pipe and a pre-installed metal valve. The principle and structure of the present utility model will be described in detail below with reference to the accompanying drawings and embodiments.

[0021] Embodiment 1

[0022] Please refer to Figure 1 , the present utility model proposes a connection structure between a metal pipe and a PE pipe, including a sleeve 1 and a PE pipe 2. The sleeve 1 is made of metal. One end of the sleeve 1 is provided with an external thread, and one end of the PE pipe 2 is provided with an internal thread. The sleeve 1 and the PE pipe 2 are connected by threads. A sleeve 3 is connected to the sleeve 1. An annular connection groove 4 is formed between the sleeve 1 and the sleeve. The thickness of the annular connection groove 4 formed between the outer wall of the sleeve 1 and the inner wall of the sleeve 3 is less than the wall thickness of the PE pipe 2, which is an interference fit. The width of the sleeve 3 is greater than the thread length of the sleeve 1 and the PE pipe 2. Both the sleeve 1 and the sleeve 3 are made of metal and are fixedly connected by circumferential welding.

[0023] In specific applications, first, the sleeve 1 and the PE pipe 2 are tightened by threads, and then the sleeve 3 is heated. Utilizing the characteristic that the PE pipe 2 is easily deformed by heat, the heated sleeve 3 is sleeved on the threaded connection part of the sleeve 1 and the PE pipe 2 by a press. The sleeve 3 is heated and then kept warm and under pressure for a period of time. In this way, the formed interference fit can effectively make the internal and external threads on the sleeve 1 and the PE pipe 2 fit tightly together. Finally, the sleeve 3 and the sleeve 1 are welded together by circumferential welding.

[0024] Please continue to participate in Figure 1 , the bottom of the annular connection groove 4 formed by the sleeve 1 and the sleeve 3 is a threadless part, and the outer diameter of this part is greater than the outer diameter of the external thread part of the sleeve 1. In this way, after the sleeve 1 and the sleeve 3 are welded, a part of the bottom of the formed annular connection groove 4 has no external thread, and at the same time, the outer diameter of this part is greater than the outer diameter of the threaded part of the sleeve 1. This can make the gap width of the annular connection groove 4 decrease gradually. When the sleeve 3 is pressed by a press, it can be more smoothly pressed while ensuring the pressure.

[0025] Please continue to refer to Figure 1 , an annular groove is provided at the threadless part at the bottom of the annular connection groove 4 formed by the sleeve 1 and the sleeve 3, and an O-ring 5 is correspondingly provided in the annular groove. The number of O-rings 5 is at least 1. In this way, after pressing, the sealing performance between the sleeve 1 and the PE pipe 2 can be improved.

[0026] At the bottom position of the annular connection groove 4 formed by the sleeve 1 and the casing 3, there is an anti-pulling groove 6, and the thickness of the anti-pulling groove 6 is greater than the thickness of the annular connection groove 4 formed by the sleeve 1 and the casing 3. The inner wall of the casing 3 is also provided with fine threads. Through the pressing of the press and heating and heat preservation for a period of time, the front end of the PE pipe 2 is heated and deformed and will fill into the anti-pulling groove 6. The thickness of the anti-pulling groove is greater than the thickness of the annular connection groove 4 formed by the sleeve 1 and the casing 3, which can effectively prevent pulling off, so that the front end of the PE pipe 2 is stuck in the anti-pulling groove 6. At the same time, the inner wall of the casing 3 is also provided with fine threads, which can increase the friction between the inner wall of the casing 3 and the outer wall of the PE pipe 2, further improve the connection strength and prevent pulling off.

[0027] Based on the same concept, the present utility model also provides a pre-installed metal valve, which includes a valve body 7. The two sides of the valve body 7 are connected with sleeves 1, and the sleeves 1 are connected with PE pipes 2. The above connection structure of the sleeves 1 and the PE pipes 2 is adopted. The sleeves 1 and the valve body 7 are connected by circumferential welding. That is, the sleeves 1 and the PE pipes 2 are fixedly connected in the above manner and heated and sleeved with the casing 3, and then the sleeves and the valve body 1 are welded and fixed. In this way, when the valve is connected to the PE pipeline on site subsequently, the hot melt connection method is directly adopted, which can effectively improve the work efficiency on site.

[0028] The above is only the preferred embodiment of the present utility model and is not intended to limit the present utility model. For those skilled in the art, the present utility model can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A metal pipe and PE pipe connection structure, characterized in that: The invention comprises a sleeve (1) and a PE tube (2), wherein one end of the sleeve (1) is provided with an external thread, and one end of the PE tube (2) is provided with an internal thread, the sleeve (1) and the PE tube (2) are threadedly connected, a sleeve (3) is connected to the sleeve, the sleeve (1) and the sleeve form an annular connection groove (4), the gap thickness of the annular connection groove (4) is less than the wall thickness of the PE tube (2), and is an interference fit, the width of the sleeve (3) is greater than the thread length of the sleeve (1) and the PE tube (2), and the sleeve (1) and the sleeve (3) are both made of metal and are fixedly connected by ring welding.

2. A metal pipe and PE pipe connection structure according to claim 1, characterized in that: The bottom of the annular connecting groove (4) formed by the sleeve (1) and the casing (3) is a non-threaded portion, and the outer diameter of this portion is larger than the outer diameter of the external threaded portion of the sleeve (1).

3. A metal pipe and PE pipe connection structure according to claim 2, characterized in that: An annular groove is provided at a non-threaded portion at the bottom of the annular connecting groove (4) formed by the sleeve (1) and the casing (3), and an O-ring (5) is correspondingly provided in the annular groove.

4. A metal pipe and PE pipe connection structure according to claim 3, characterized in that: The number of the O-ring (5) is at least one.

5. A metal pipe and PE pipe connection structure according to claim 4, characterized in that: An anti-slip groove (6) is provided at the bottom of the annular connecting groove (4) formed by the sleeve (1) and the sleeve (3); the thickness of the anti-slip groove (6) is greater than the thickness of the annular connecting groove (4) formed by the sleeve (1) and the sleeve (3).

6. A metal pipe and PE pipe connection structure according to claim 5, characterized in that: The inner wall of the sleeve (3) is also provided with fine threads.

7. A preassembled metal valve, characterized in that: The invention comprises a valve body (7), sleeves (1) are connected to both sides of the valve body (7), a PE pipe (2) is connected to the sleeve (1), the sleeve (1) and the PE pipe (2) adopt the sleeve and PE pipe connection structure as claimed in any one of claims 1 to 6, and the sleeve (1) and the valve body (7) are connected by ring welding.

Images