Flange sealing structure

Abstract

The flange sealing structure comprises a flange and a bushing ring which are coaxially connected, a flange hole penetrating in the axial direction of the flange is formed in the middle of the flange, a first groove is formed in one end face of the flange, an annular positioning protrusion is arranged in the first groove and arranged in the circumferential direction of the flange hole, and one end face of the bushing ring is connected into the first groove; one end face of the bushing ring is provided with a first groove and is matched with the first groove in shape, the other end face of the bushing ring is provided with an annular second groove, the annular second groove is arranged in the circumferential direction of the bushing ring and extends downwards in the axial direction of the bushing ring, and a sealing ring is contained in the second groove. The flange and the bushing ring are matched through the annular concave-convex grooves, it is guaranteed that the inner side and the outer side of the sealing face bushing ring are restrained by the flange, the problem that the sealing face deforms due to stress is solved, and the sealing structure has the advantages of being reliable in sealing, high in connection strength and high in practicability.

Description

Technical Field

[0001] The present application relates to the technical field of connection and sealing, and in particular to a flange sealing structure for chemical pipeline connection. Background Art

[0002] Pipelines are often used in chemical production. Existing chemical pipelines are often connected using flanges. The most common problem with pipeline connections is leakage at the pipeline joints.

[0003] Take pressure vessels as an example. When pressure vessels need to hold corrosive media, they need to use corrosion-resistant metals such as titanium and zirconium. Because titanium and zirconium are expensive, the conventional method is to line the steel with a layer of titanium or zirconium as a corrosion-resistant layer. In addition, since titanium, zirconium and other materials are difficult to weld directly to steel, they also need to be sealed or silver brazed or titanium screws and then titanium plug welding for further fixation. Accordingly, the flange sealing structure of the pipeline outlet may need to be treated with corrosion resistance, such as Figure 1 As shown, existing flange sealing structures mostly use a ring sealing liner and a cylindrical liner for sealing welding, a ring sealing liner and a flange for silver brazing, or a ring sealing liner connected to the flange using titanium or zirconium screws evenly distributed around the circumference, and then a gasket is installed to increase the sealing of the connection. However, for octagonal gaskets and elliptical gaskets, when the studs are tightened, the octagonal gasket or elliptical gasket will generate inward and outward squeezing force at the gasket contact point of the ring sealing liner. Under the action of the force, the liner tends to move to its sides, which can easily cause the silver brazing welding between the outer ring of the liner and the flange and the sealing weld between the inner ring and the liner to become desoldered, affecting the seal. At the same time, the pressure vessel is repeatedly heated, and the high temperature further exacerbates the cracking problem of the titanium, zirconium and steel welds, affecting the life of the flange.

[0004] Therefore, there is an urgent need for a flange sealing structure with reliable sealing, stable connection and long service life. Utility Model Content

[0005] The purpose of this application is to provide a flange sealing structure to solve the problems of low connection strength and poor sealing in the prior art.

[0006] The embodiments of the present application can be implemented through the following technical solutions:

[0007] A flange sealing structure includes a flange and a backing ring connected coaxially. A flange hole is formed in the middle of the flange and extends axially therethrough. A first groove is formed on one end surface of the flange. An annular positioning protrusion is provided in the first groove. The annular positioning protrusion is arranged circumferentially along the flange hole. One end surface of the backing ring is connected to the first groove and matches the shape of the first groove.

[0008] An annular second groove is provided on the other end surface of the liner ring. The annular second groove is provided along the circumference of the center hole of the liner ring and extends downward along the axial direction of the liner ring. A sealing ring is provided in the second groove.

[0009] Furthermore, an annular third groove is provided on the lower end surface of the liner ring. The annular third groove is provided along the circumference of the center hole of the liner ring. The third groove is matched and connected with the positioning protrusion.

[0010] Furthermore, the outer diameter of the positioning protrusion is l1, the inner diameter of the second groove is l2, and l1 <l2。

[0011] Furthermore, the height of the positioning protrusion is h1, the height of the liner ring is h2, and h1≤1 / 2h2.

[0012] Furthermore, the radial width between the inner and outer walls of the positioning protrusion is d1, the radial width between the inner and outer walls of the liner ring is d2, and d1≤1 / 4d2.

[0013] Furthermore, the inner wall of the flange hole is connected with a lining, and the lining is a corrosion-resistant metal material made of titanium or zirconium.

[0014] Furthermore, a welding notch groove is provided on the lower end surface of the center hole of the liner ring. When the flange is connected to the liner ring, one end of the liner extends into the welding notch groove.

[0015] Furthermore, the inner wall of the center hole of the liner ring is further provided with a fourth groove arranged along its circumference, the fourth groove being arranged above the welding notch groove and having an extended length along the radial direction of the liner ring;

[0016] A bottom surface of the fourth groove is lower than a bottom surface of the second groove.

[0017] Furthermore, the outer side of the first groove abuts against the outer ring of the liner ring and is fixed by silver brazing.

[0018] Furthermore, the end face of the flange is further provided with a bolt connection hole extending through the flange in its axial direction. The number of the bolt connection holes is at least two, and the at least two bolt connection holes are respectively provided on both sides of the first groove.

[0019] The flange sealing structure provided by the embodiments of the present application has at least the following beneficial effects:

[0020] 1. The flange and the liner ring adopt annular concave and convex grooves to cooperate with each other, ensuring that the inner and outer sides of the ring sealing surface are constrained by the flange, solving the problem of deformation of the sealing surface under stress, and having the advantages of reliable sealing, high connection strength and strong practicality.

[0021] 2. By providing the fourth groove, the force transmitted to the weld is further released through deformation, thereby more effectively protecting the sealing weld.

[0022] 3. This application realizes the processing and manufacturing of the ring seal liner ring through machining combined with silver brazing, which has the advantages of simple structure and easy assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a side cross-sectional schematic diagram of a flange sealing structure in the prior art;

[0024] Figure 2 Schematic side section of the flange sealing structure in this application;

[0025] Figure 3 This is a side cross-sectional diagram of two flange sealing structures in this application when assembled in an application scenario;

[0026] Figure 4 This is a side cross-sectional diagram of the flange sealing structure in the present application in an exploded state;

[0027] Figure 5 It is a side sectional schematic diagram of the flange sealing structure with the fourth groove in this application.

[0028] Numbers in the figure

[0029] 1-flange; 10-flange hole; 11-first groove; 12-bolt connection hole; 13-positioning protrusion; 2-lining ring; 20-lining ring center hole; 21-second groove; 22-third groove; 23-welding notch groove; 24-fourth groove; 3-first welding point; 4-second welding point; 7-lining. DETAILED DESCRIPTION

[0030] Hereinafter, the present application will be further described based on preferred embodiments with reference to the accompanying drawings.

[0031] In addition, for ease of understanding, various components in the drawings are enlarged (thickened) or reduced (thinned), but this practice is not intended to limit the scope of protection of this application.

[0032] Words importing the singular include the plural and vice versa.

[0033] In the description of the embodiments of the present application, it should be noted that if the terms "upper", "lower", "inner", "outer" and the like indicate an orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or are the orientation or positional relationship in which the products of the embodiments of the present application are usually placed when in use, they are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, in the description of the present application, in order to distinguish different units, words such as first and second are used in this specification, but these are not limited by the order of manufacture, nor can they be understood as indicating or implying relative importance. Their names may be different in the detailed description and claims of the present application.

[0034] The vocabulary in this specification is used to illustrate the embodiments of the present application, but is not intended to limit the present application. It should also be noted that, unless otherwise clearly specified and limited, the terms "disposed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, a direct connection, an indirect connection through an intermediate medium, or a communication between the two components. For those skilled in the art, the specific meanings of the above terms in this application can be specifically understood.

[0035] like Figures 2 to 5 As shown, a flange sealing structure includes a flange 1 and a liner ring 2 connected coaxially. The flange 1 is a cylindrical structure with a flange hole 10 in the middle. A first groove 11 is provided on one end face of the flange 1. An annular positioning protrusion 13 is provided in the first groove 11. The annular positioning protrusion 13 is circumferentially arranged along the flange hole 10 and is used as a limiting structure for the connecting surface of the first groove 11. The liner ring 2 is fitted and connected in the first groove 11, and the shape of the end face of the liner ring 2 connected in the first groove 11 is adapted to the shape of the connecting surface in the first groove 11, so that the flange 1 and the liner ring 2 can be tightly connected together through the matching concave and convex structures.

[0036] Furthermore, a center hole 20 is provided in the middle of the liner ring 2 and passes through the liner ring 2 in its axial direction. An annular second groove 21 is provided on the liner ring 2. The annular second groove 21 is circumferentially arranged along the center hole and extends downward in the axial direction of the liner ring 2. The second groove 21 is used to accommodate a forced sealing ring such as an octagonal washer or an elliptical washer.

[0037] like Figure 3As shown, with the above settings, when a sealing ring is placed in the second groove 21 and the two flange sealing structures are fastened by bolts at the bolt connection holes 12, even though the washer will generate a radial squeezing force on the periphery of the second groove 21 during the fastening process, the positioning protrusion 13 can block the displacement tendency of the lining ring 2.

[0038] In some preferred embodiments, the bolt connection holes 12 penetrate axially along the end face of the flange 1, and the number of the bolt connection holes 12 is at least two. At least two bolt connection holes 12 are respectively arranged on both sides of the first groove 11 for connecting the two flange sealing structures outside the first groove 11 through bolts.

[0039] Specifically, as Figure 2 shown, an annular third groove 22 is provided on the lower end face of the lining ring 2. The annular third groove 22 is arranged along the circumferential direction of the lining ring 2. The third groove 22 is matched with the positioning protrusion 13 for realizing the radial positioning when the flange 1 and the lining ring 2 are connected through the mutually matched concave and convex structures.

[0040] In some preferred embodiments, the outer diameter of the positioning protrusion 13 is l1, and the inner diameter of the second groove 21 is l2, and l1 < l2, so that when the bolt is fixed in the bolt connection hole 12, the positioning protrusion 13 can effectively block the radial acting force transmitted by the gasket in the second groove 21.

[0041] In some preferred embodiments, as Figure 4 shown, the height of the positioning protrusion 13 is h1, and the height of the lining ring 2 is h2, and h1 ≤ 1 / 2h2, to avoid the height of the positioning protrusion 13 being too high and reducing the overall strength of the lining ring 2.

[0042] In some preferred embodiments, the radial width of the positioning protrusion 13 is d1, and the radial width between the inner and outer walls of the lining ring 2 is d2, and d1 ≤ 1 / 4d2, to avoid the positioning protrusion 13 being too wide and reducing the overall strength of the lining ring 2.

[0043] In some preferred embodiments, a lining 7 is connected to the inner wall of the flange hole 10. The lining 7 is made of corrosion-resistant metal materials such as titanium or zirconium for increasing the corrosion resistance of the flange 1.

[0044] In some preferred embodiments, as Figure 4As shown, the center hole 20 of the liner ring has an inner wall of unequal diameter, that is, a welding notch groove 23 is provided on the lower end face of the center hole 20 of the liner ring. When the flange 1 is connected to the liner ring 2, one end of the liner 7 extends into the welding notch groove 23, which is used to seal-weld the lower end face of the center hole 20 of the liner ring to the liner 7 by sealing welding to form a first welding point 3, thereby enhancing welding stability.

[0045] In some preferred embodiments, Figure 5 As shown, the inner wall of the center hole 20 of the liner ring is further provided with a fourth groove 24 arranged along its circumference. The fourth groove 24 is arranged above the welding notch groove 23 and has an extended length along the radial direction of the liner ring 2. The bottom surface of the fourth groove 24 is lower than the bottom surface of the second groove 21, so that the force transmitted to the liner ring 2 during the tightening of the bolt can achieve a certain slight deformation through the fourth groove 24, thereby protecting the sealing weld while meeting the sealing conditions.

[0046] In some preferred embodiments, the outer side of the first groove 11 abuts against the outer ring of the backing ring 2 and is fixed by silver brazing to form a second welding point 4 for enhancing the stability of the connection.

[0047] The above is a detailed introduction to the specific implementation methods of the present application. For those skilled in the art, several improvements and modifications can be made to the present application without departing from the principles of the present application. These improvements and modifications also fall within the scope of protection of the claims of the present application.

Claims

1. A flange sealing structure, comprising a flange (1) and a liner ring (2) connected coaxially, wherein a flange hole (10) is provided in the middle of the flange (1) and extends through the flange along its axial direction, and wherein: One end surface of the flange (1) is provided with a first groove (11), and an annular positioning protrusion (13) is provided in the first groove (11). The annular positioning protrusion (13) is arranged along the circumference of the flange hole (10). One end surface of the liner ring (2) is connected to the first groove (11) and is adapted to the shape of the first groove (11). An annular second groove (21) is provided on the other end surface of the liner ring (2). The annular second groove (21) is provided along the circumference of the liner ring center hole (20) and extends downward along the axial direction of the liner ring (2). A sealing ring is accommodated in the second groove (21).

2. The flange sealing structure according to claim 1, characterized in that: The lower end surface of the liner ring (2) is provided with an annular third groove (22), and the annular third groove (22) is arranged along the circumference of the liner ring center hole (20), and the third groove (22) is matched and connected with the positioning protrusion (13).

3. The flange sealing structure according to claim 1, characterized in that: The outer diameter of the positioning protrusion (13) is l1, and the inner diameter of the second groove (21) is l2. <l2。 4. The flange sealing structure according to claim 1, wherein: The height of the positioning protrusion (13) is h1, the height of the liner ring (2) is h2, and h1≤1 / 2h2.

5. The flange sealing structure according to claim 1, wherein: The radial width between the inner and outer walls of the positioning protrusion (13) is d1, and the radial width between the inner and outer walls of the liner ring (2) is d2, where d1≤1 / 4d2.

6. The flange sealing structure according to claim 1, wherein: The inner wall of the flange hole (10) is connected with a lining (7), and the lining (7) is a corrosion-resistant metal material made of titanium or zirconium.

7. The flange sealing structure according to claim 6, characterized in that: A welding notch groove (23) is provided on the lower end surface of the liner ring center hole (20). When the flange (1) is connected to the liner ring (2), one end of the liner (7) extends into the welding notch groove (23).

8. The flange sealing structure according to claim 7, characterized in that: The inner wall of the liner ring center hole (20) is further provided with a fourth groove (24) arranged along its circumference, the fourth groove (24) being arranged above the welding notch groove (23) and having an extended length along the radial direction of the liner ring (2); The bottom surface of the fourth groove (24) is lower than the bottom surface of the second groove (21).

9. The flange sealing structure according to claim 8, characterized in that: The outer side of the first groove (11) abuts against the outer ring of the liner ring (2) and is fixed by silver brazing.

10. The flange sealing structure according to claim 1, wherein: The end surface of the flange (1) is further provided with a bolt connection hole (12) extending through the flange along its axial direction. The number of the bolt connection holes (12) is at least two, and the at least two bolt connection holes (12) are respectively provided on both sides of the first groove (11).

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