A multiple seal threaded fitting

Abstract

The utility model relates to the technical field of threaded joint, especially to a multiple sealing threaded joint. First pipeline joint and second pipeline joint are connected through the first connecting sleeve and the second connecting sleeve, and the connecting pipe sleeve is arranged outside the connection of the first pipeline joint and the second pipeline joint. The utility model provides a threaded joint with multiple sealing barriers, which can significantly improve the overall sealing performance and stability of the joint.

Description

Technical Field

[0001] This utility model relates to the field of threaded joint technology, and in particular to a multi-seal threaded joint. Background Technology

[0002] Pipeline connections are an indispensable basic component of industrial piping systems, among which threaded fittings are widely used due to their simple structure and convenient assembly / disassembly. They primarily achieve connection and sealing between pipe sections through the engagement of threads, and are commonly used in pipeline systems transporting media such as water, oil, and gas. Ensuring the sealing reliability of threaded fittings during long-term use, especially under high pressure, corrosive, or vibrating conditions, is a key technical focus that continues to be addressed in this field.

[0003] However, currently common threaded joint structures are relatively simple, and their sealing performance mainly relies on the tightness of the threaded fit or the addition of a single sealing element at the threaded location. This single sealing method has certain limitations: under the influence of system pressure fluctuations, temperature changes, or mechanical vibrations, the single sealing interface is prone to failure due to material fatigue or preload decay, leading to media leakage. In addition, traditional joint structures lack effective barriers against external environmental erosion (such as moisture and corrosive substances), making it difficult to meet the sealing requirements of higher reliability and longer service life. Utility Model Content

[0004] This invention provides a threaded joint with multiple sealing barriers that can significantly improve the overall sealing performance and stability of the joint.

[0005] The technical solution adopted by this utility model is as follows: a multi-seal threaded joint, including a first pipe joint and a second pipe joint, a first connecting sleeve is fixedly sleeved on the outside of the first pipe joint, a second connecting sleeve is fixedly sleeved on the outside of the second pipe joint, the first connecting sleeve and the second connecting sleeve are connected by a connecting tube sleeve and the connecting tube sleeve is sleeved on the outside of the connection between the first pipe joint and the second pipe joint.

[0006] As a further improvement of this utility model, one end of the first pipe joint is threadedly connected to a sealing tube, and the end of the sealing tube away from the first pipe joint is inserted into the interior of the second pipe joint.

[0007] As a further improvement of this utility model, the sealing tube is fixedly sleeved with a retaining ring in the middle and has an external thread on the outer surface of the retaining ring on one side, and the inner surface of the first pipe joint is provided with an internal thread that matches the external thread.

[0008] As a further improvement of this utility model, a sealing ring is provided on both sides of the retaining ring on the outer side of the sealing tube.

[0009] As a further improvement of this utility model, the first connecting sleeve is integrally connected with the first pipe joint, the second connecting sleeve is integrally connected with the second pipe joint, and the retaining ring is integrally connected with the sealing tube.

[0010] As a further improvement of this utility model, the outer surface of the first connecting sleeve and the second connecting sleeve near the connecting tube sleeve is provided with external thread II, and the inner surface of both ends of the connecting tube sleeve is provided with internal thread II that matches the external thread II.

[0011] As a further improvement of this utility model, a sealing ring is provided at the connection between the first connecting sleeve and the connecting tube sleeve, and at the connection between the second connecting sleeve and the connecting tube sleeve.

[0012] As a further improvement of this utility model, both the sealing ring one and the sealing ring two are made of rubber.

[0013] The beneficial effects of this utility model are as follows: By setting an external connection structure consisting of a first connecting sleeve, a second connecting sleeve, and a connecting tube sleeve, and combining it with an internally insertable sealing tube and multiple sealing rings, a multi-level and multi-pass sealing barrier is formed inside the joint, which greatly improves the overall sealing reliability, vibration resistance, and protection against external environmental corrosion of the joint. The structure is compact and easy to install. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of a multi-seal threaded joint according to this utility model; Figure 2 This is a structural breakdown of a multi-seal threaded joint according to the present invention. Figure 1 ; Figure 3 This is a structural breakdown of a multi-seal threaded joint according to this utility model. Figure 2 ; Figure 4 This is a structural breakdown of a multi-seal threaded joint according to the present invention. Figure 3 ; Figure 5 This is a partial sectional view of a threaded joint with multiple seals according to this utility model.

[0015] As shown in the figure: 1. First pipe joint; 2. Second pipe joint; 3. First connecting sleeve; 4. Second connecting sleeve; 5. Connecting pipe sleeve; 6. Sealing insert; 601. Retaining ring; 7. Sealing ring one; 8. Sealing ring two. Detailed Implementation

[0016] The directional terms such as up, down, left, right, front, back, front, back, top, and bottom mentioned or possibly mentioned in this specification are defined relative to their structure and are relative concepts. Therefore, they may vary depending on their location and usage; thus, these or other directional terms should not be interpreted as restrictive terms.

[0017] The singular forms “a,” “the,” and “the” used in this specification are intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes one or more of the associated listed items, any or all possible combinations thereof.

[0018] To make the technical problems to be solved, the technical solutions, and the beneficial effects of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0019] This utility model provides the following: Figure 1-5 The threaded joint with multiple seals shown includes a first pipe joint 1 and a second pipe joint 2. The first pipe joint 1 is fixedly sleeved with a first connecting sleeve 3 on its outer side, and the second pipe joint 2 is fixedly sleeved with a second connecting sleeve 4 on its outer side. The first connecting sleeve 3 and the second connecting sleeve 4 are connected by a connecting tube sleeve 5, and the connecting tube sleeve 5 is sleeved on the outer side of the connection between the first pipe joint 1 and the second pipe joint 2.

[0020] like Figure 2-5 As shown, in this utility model, one end of the first pipe joint 1 is threadedly connected to a sealing tube 6, and the end of the sealing tube 6 away from the first pipe joint 1 is inserted into the interior of the second pipe joint 2. A retaining ring 601 is fixedly sleeved in the middle of the sealing tube 6, and an external thread is provided on the outer surface of the retaining ring 601. An internal thread is provided on the inner surface of one end of the first pipe joint 1 that matches the external thread. Sealing rings 7 are sleeved on both sides of the retaining ring 601 on the outer side of the sealing tube 6. The sealing rings 7 are made of rubber.

[0021] By screwing the external thread 1 and the internal thread 1 together, the sealing tube 6 can be securely installed at the end of the first pipe joint 1. During the tightening process, the retaining ring 601 can effectively limit the screwing depth of the sealing tube 6, ensuring that its insertion length into the second pipe joint 2 is precisely controllable, and avoiding the sealing effect due to excessive or insufficient screwing. When the sealing tube 6 is screwed in place, the sealing rings 7 on both sides of the retaining ring 601 are tightly pressed between the end face of the retaining ring 601 and the end face of the first pipe joint 1, and between the retaining ring 601 and the end face of the second pipe joint 2, respectively, forming two initial sealing interfaces. The rubber sealing rings 7 undergo elastic deformation under compression, which can fully fill any small gaps that may exist between the sealing tube 6 and the first pipe joint 1 and the second pipe joint 2, effectively preventing the medium from leaking from the inside of the pipe along the surface of the sealing tube 6.

[0022] In this utility model, the first connecting sleeve 3 is integrally connected with the first pipe joint 1, the second connecting sleeve 4 is integrally connected with the second pipe joint 2, and the retaining ring 601 is integrally connected with the sealing tube 6. This enhances the structural strength and stability of the connection between the components, avoids the risk of sealing failure caused by assembly gaps, simplifies the production and processing process, and ensures the dimensional accuracy of key sealing parts.

[0023] like Figure 2-5 As shown, in this utility model, the outer surface of the first connecting sleeve 3 and the second connecting sleeve 4 near the connecting tube sleeve 5 is provided with external threads II, and the inner surfaces of both ends of the connecting tube sleeve 5 are provided with internal threads II that are compatible with the external threads II. The connection between the first connecting sleeve 3 and the connecting tube sleeve 5 and the connection between the second connecting sleeve 4 and the connecting tube sleeve 5 are both provided with sealing ring II 8, which is made of rubber.

[0024] Through the engagement of the external thread and the internal thread, the connecting sleeve 5 can simultaneously screw onto the ends of the first connecting sleeve 3 and the second connecting sleeve 4, thereby completely covering the connection area of ​​the first pipe joint 1 and the second pipe joint 2. During the tightening process of the connecting sleeve 5, its two ends exert axial pressure on the sealing rings 8 between the first connecting sleeve 3 and the connecting sleeve 5, and between the second connecting sleeve 4 and the connecting sleeve 5, respectively. Under pressure, the rubber sealing rings 8 undergo elastic deformation, tightly filling the thread gaps and mating gaps between the inner wall of the connecting sleeve 5 and the outer walls of the first and second connecting sleeves 3 and 4, forming two external sealing barriers. These two external seals not only effectively prevent external moisture, dust, corrosive media, etc., from intruding into the joint, avoiding corrosion of the internal sealing components and thread structure, but also provide auxiliary compression to the internal sealing ring 7, further improving the overall sealing stability.

[0025] Working principle: In the specific implementation of this utility model, the components need to be pre-assembled first: two sealing rings are respectively fitted into the preset grooves on both sides of the sealing tube located on the retaining ring, ensuring that the sealing rings fit tightly with the outer surface of the sealing tube without twisting; then the end of the sealing tube with the external thread is screwed into the internal thread of the first pipe joint until the retaining ring fits completely with the end face of the first pipe joint. At this time, the sealing ring on the left side of the retaining ring is compressed between the retaining ring and the end face of the first pipe joint, forming the first internal axial seal. Next, the first pipe connector and the second pipe connector are joined together, so that the end of the sealing tube furthest from the first pipe connector is coaxially inserted into the internal insertion hole of the second pipe connector. During insertion, it is necessary to ensure that the gap between the outer wall of the sealing tube and the inner wall of the second pipe connector is uniform. When the sealing tube is inserted to the preset depth, the sealing ring one on the right side of the retaining ring is precisely squeezed between the retaining ring and the end face of the second pipe connector, forming a second internal axial seal. At the same time, the outer surface of the sealing tube and the inner surface of the second pipe connector form a circumferential seal through the radial deformation of the sealing ring one, constituting an internal composite sealing structure. Before completing the joining of the internal sealing tubes, sealing ring two is respectively fitted onto the external threads two near the ends of the first connecting sleeve and the second connecting sleeve, and the connecting tube sleeve is fitted outside the connection between the first pipe connector and the second pipe connector, ensuring that the sealing ring two is located inside both ends of the connecting tube sleeve. Subsequently, by rotating the connecting tube sleeve, the internal threads two at both ends are gradually screwed into the external threads two of the first connecting sleeve and the second connecting sleeve, respectively. During tightening, tools such as wrenches should be used to apply force evenly to ensure that both ends of the connecting sleeve are tightened synchronously, avoiding uneven force that could cause eccentricity of the pipe joint or inconsistent compression of the sealing rings. When the connecting sleeve is tightened to the preset torque, the inner walls at both ends tightly compress the corresponding sealing rings. Under axial pressure, the sealing rings expand radially, completely filling the gaps between the connecting sleeve and the first and second connecting sleeves, thus forming two annular sealing barriers on the outside of the joint. At this point, the two inner sealing rings and the two outer sealing rings together constitute a four-fold sealing protection system: the inner first sealing ring prevents the medium from leaking from the threaded connection between the first pipe joint and the sealing tube; the inner second sealing ring prevents the medium from leaking along the gap between the sealing tube and the second pipe joint; the outer first sealing ring blocks external corrosive media from intruding from the threaded gaps between the first connecting sleeve and the connecting sleeve; and the outer second sealing ring further isolates the external environment from the connection between the second connecting sleeve and the connecting sleeve. Meanwhile, the overall encapsulation structure of the connecting sleeve provides rigid support for the internal sealing tube and pipe joint mating area, effectively resisting connection loosening caused by system vibration or external impact, and ensuring that the preload of each sealing interface remains stable over a long period. During media transportation, when internal pressure fluctuates, the rubber material of sealing ring one and sealing ring two will dynamically compensate through its own elastic deformation, always maintaining a tight fit with the sealing surface, significantly reducing the risk of single seal failure.In addition, the integrated connection structure between the components (such as the first connecting sleeve and the first pipe joint, the retaining ring and the sealing tube) eliminates stress concentration that may be caused by assembly gaps, improves the overall structural strength and fatigue resistance of the joint, and thus maintains excellent sealing reliability and service life under complex working conditions such as high pressure, corrosion and vibration.

[0026] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A multi-seal threaded joint, comprising a first pipe joint (1) and a second pipe joint (2), characterized in that: The first pipe joint (1) is fixedly fitted with a first connecting sleeve (3) on the outside, and the second pipe joint (2) is fixedly fitted with a second connecting sleeve (4) on the outside. The first connecting sleeve (3) and the second connecting sleeve (4) are connected by a connecting pipe sleeve (5), and the connecting pipe sleeve (5) is fitted on the outside of the connection between the first pipe joint (1) and the second pipe joint (2).

2. A threaded joint with multiple seals according to claim 1, characterized in that: One end of the first pipe joint (1) is threaded with a sealing tube (6), and the end of the sealing tube (6) away from the first pipe joint (1) is inserted into the inside of the second pipe joint (2).

3. A threaded joint with multiple seals according to claim 2, characterized in that: The sealing tube (6) is fixedly fitted with a retaining ring (601) in the middle and has an external thread on the outer surface on one side of the retaining ring (601). The inner surface of one end of the first pipe joint (1) is provided with an internal thread that matches the external thread.

4. A threaded joint with multiple seals according to claim 2, characterized in that: The sealing tube (6) is fitted with sealing rings (7) on both sides of the retaining ring (601) on the outside.

5. A threaded joint with multiple seals according to claim 3, characterized in that: The first connecting sleeve (3) is integrally connected with the first pipe joint (1), the second connecting sleeve (4) is integrally connected with the second pipe joint (2), and the retaining ring (601) is integrally connected with the sealing tube (6).

6. A threaded joint with multiple seals according to claim 1, characterized in that: The first connecting sleeve (3) and the second connecting sleeve (4) are both provided with external threads on the outer surface of the end near the connecting sleeve (5), and the inner surfaces of both ends of the connecting sleeve (5) are provided with internal threads that are compatible with the external threads.

7. A threaded joint with multiple seals according to claim 6, characterized in that: Sealing ring 2 (8) is provided at the connection between the first connecting sleeve (3) and the connecting tube sleeve (5) and at the connection between the second connecting sleeve (4) and the connecting tube sleeve (5).

8. A threaded joint with multiple seals according to claim 4, characterized in that: Both the sealing ring one (7) and the sealing ring two (8) are made of rubber.

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