RU2675635C1 - Sealing assembly and method for assembling thereof - Google Patents

Abstract

FIELD: sealing equipment.SUBSTANCE: invention relates to a sealing technique used for sealing round holes of flat flange connections, pipelines, vessels, apparatuses, pumps and similar equipment of chemical, oil refining and other industries, and more specifically to sealing assemblies based on spiral-wound gaskets, as well as to the method of their assembly. Sealing assembly comprises successively arranged inner limiting ring, a spiral-wound gasket having an outer circumferential protrusion, and an outer limiting ring having an inner circular groove in response to the outer circular protrusion of the spiral-wound gasket. Outer restrictive ring contains two ring-shaped parts, made with the possibility of connection with each other, the plane of connection of these two annular parts passes through a circle, described by the point of the inner circular groove of the outer limiting ring, the most distant from the symmetry axis of the outer limiting ring.EFFECT: technical result of the invention is to facilitate the process of assembling the sealing assembly while ensuring its sealing properties.6 cl, 8 dwg

Description

FIELD OF TECHNOLOGY

The present invention generally relates to a sealing technique used to seal round holes of flat flange joints, pipelines, vessels, apparatuses, pumps and similar equipment of chemical, oil refining and other industries, and more particularly, to sealing assemblies based on spiral wound gaskets , as well as the method of assembly.

BACKGROUND

Sealing units based on spiral wound gaskets (SNPs) are widely known in the prior art and have proven to be simple to manufacture, cheap and effective means of sealing flange joints, which, in contrast to conventional flange gaskets, have residual elasticity and make it possible to compensate for the arising gaps formed during differences in temperature and pressure of fluids, as well as vibration of the pipeline. Due to their design, SNPs can be used to seal flange joints such as tenon grooves, protrusion-troughs, and flange joints with smooth sealing surfaces.

Most SNPs are made by winding spirals from V-shaped, with a given angle of inclination and radius at the base, of alternating layers of stainless steel tape and filler, which can be thermally expanded graphite, paronite, teflon or fluoroplastic.

In addition to the spiral-wound layers of filler and steel, as described above, the sealing assembly based on SNP also contains steel restriction rings with shaped surfaces on the outer or inner side. In particular, the external restrictive ring has a circular V-shaped groove on the inner side, corresponding to the V-shaped profile of the SNP, about. the inner restrictive ring has a circular V-shaped protrusion on the outside, also corresponding to the V-shaped profile of the sealing ring. During the assembly of the sealing assemblies, a spiral wound gasket is wound directly onto the indicated V-shaped protrusion of the inner restrictive ring.

The described seal assemblies based on SNP are widely known in the art. For example, from the copyright certificate SU 1059978 (10.10.1999, F16J 15/12), a fixed joint sealing assembly is known that contains sealing means in the form of a spiral wound gasket enclosed between the inner and outer ring rings. The outer restrictive ring has a cone-shaped cross section and elastic material at the ends of c. the purpose of increasing the reliability and thermobarocyclic performance of the seal.

Despite the fact that the sealing assemblies based on SNP have established themselves as having high reliability, they still have a number of disadvantages associated with their assembly. In particular, there are problems associated with the insertion of an external restrictive ring on a spiral wound gasket due to the presence of shaped surfaces. In practice, such an installation is often made by applying pressure to a spring restrictive ring, for example, using a hammer, which inevitably leads to deformations of the wound structure. The described technical problem is relevant, and solutions aimed at eliminating it are known from the prior art.

In particular, from the patent US 5669613 (09/23/1997, F16J 15/00), a technical solution is known, according to which it is proposed to replace the outer restrictive ring with a disk in which the part having the smallest diameter is bent and repeats the shape of the V-shaped protrusion of the sealing ring with so that this bent part lies on half of the outer V-shaped protrusion of the SNP. Further, this disk is proposed to be attached to the SNP by spot welding. Such a solution really allows you to avoid installation by rough methods, such as installing with a hammer, but using a disk instead of a full restrictive ring reduces the strength of the entire assembly as a whole and increases the likelihood of laying failure at high pressures. In addition, the use of disk welding directly from the SPS imposes technological limitations on the wound structure, since its outer layer must be completely metal, and the metal itself must be selected so that it is possible to weld with the disk material.

Another solution aimed at eliminating this problem that occurs when assembling the sealing assembly is the solution described in the application US 20050206092 (09/22/2005, F16L 017/06), which proposes to change the groove geometry of the outer restrictive ring of the sealing assembly so that the protruding part of the SPS entered the groove without obstacles. In one embodiment of the invention, it is proposed to form a V-shaped groove, but one of the groove surfaces must have a more obtuse angle of inclination when the plane passes through the axis of the gasket. In some embodiments, one surface of the groove may open the protrusion of the SOR completely. Despite the fact that the known design allows to solve the indicated problem associated with the assembly of the sealing assembly, the problem of retaining the SOR in the groove of the outer restrictive ring remains unsolved in this design, since the groove of the changed shape does not allow reliable holding of the SOR within the bounding ring when external effects, such as temperature spikes or vibrations.

Another solution aimed at eliminating the problem under consideration is the technical solution described in the application for invention KR 20130010296 (03/10/2014, F16J 15/06), selected as a prototype. According to this technical solution, the sealing assembly comprises a sequentially arranged inner restriction ring, a spiral wound gasket wound on the inner restriction ring and the outer restriction ring. In this case, the spiral-wound gasket has an external circular protrusion of a V-shaped shape, and the external restrictive ring has a reciprocal circular groove to accommodate the external circular protrusion of the spiral-wound gasket. In the assembly process of the sealing assembly, a helically wound gasket is wound onto the inner restrictive ring, and then an external restrictive end is installed by placing said outer circular protrusion of the spiral wound gasket in the groove of the outer restrictive ring. In this case, before installing the outer restrictive ring, it is bent so that the protrusion can enter the hole, and then pressure is applied to the sealing assembly, ensuring that the external restrictive ring returns to its original, position and the protrusion is completely placed in the groove. However, a change in the shape of the outer restrictive ring causes stress in the metal at the periphery of the ring. These stresses affect the durability of the entire sealing assembly. In addition, the application of pressure to the sealing assembly may entail deformation of the spiral wound gasket, and as a result, loss of its sealing ability.

Thus, we can conclude that there is a problem of ensuring the integrity of the spiral wound gasket during the assembly of the sealing assembly.

SUMMARY OF THE INVENTION

According to the present invention, there is provided a sealing assembly comprising a sequentially arranged inner restriction ring, a spiral wound gasket having an outer circular protrusion, and an external restriction ring having an internal circular groove corresponding to the outer circular protrusion of the spiral-wound gasket, the outer restriction ring comprising two annular parts made with the possibility of connection with each other, while the plane of connection of the annular parts passes through the circumferential the axis described by the point of the inner circular groove of the outer limit ring, the farthest from the axis of symmetry of the outer limit ring.

The use of an external restrictive ring containing two annular parts connected during the assembly of the product makes it easier to assemble the product and at the same time ensures accurate positioning of the external circular protrusion of the spiral wound gasket in the internal circular groove of the external restrictive ring, eliminating their possible displacement relative to each other in the subsequent clamping the spiral wound gasket in the outer restrictive ring. In addition, the use of an external restrictive ring of the proposed design allows to reduce the force impact on the specified external circular protrusion of a spiral wound gasket during assembly. As a result, the use of the proposed design avoids deformations of the spiral wound gasket during assembly of the sealing assembly and ensures the preservation of its sealing properties. Thus, a technical result is achieved, which consists in facilitating the assembly process of the sealing assembly while maintaining its sealing properties.

According to one embodiment of the present invention, one annular portion has at least one groove located on its side facing another annular portion that has at least one protrusion corresponding to the specified groove. This design provides additional protection against the effects of radially outward forces arising from squeezing the sealing ring in the flange connection, which tend to separate the two ring-shaped parts from each other at the point of the inner circumferential groove of the outer limit ring that is farthest from its axis of symmetry.

According to another embodiment of the present invention, at least one annular part has through holes for making a detachable or integral connection of said two annular parts. Thanks to this design, protection is also provided against the effects of radially outward forces arising from the compression of the sealing ring in the flange joint, which tend to separate the two ring-shaped parts from each other.

The present invention also provides a method for assembling a sealing assembly, which consists in winding a spiral wound gasket onto an inner ring of restriction and then installing an external restriction ring on a spiral wound gasket with an outer circular protrusion of the spiral wound gasket in the inner circular groove of the outer ring of restriction, wherein use an external restrictive ring containing two annular parts made with the possibility of connection with each other, When installing an external restrictive ring, first one ring-shaped part is installed on the spiral-wound gasket, placing it on one side of the outer circular protrusion of the spiral-wound gasket, then another ring-shaped part is installed on the other side of the outer circular protrusion of the spiral-wound gasket, combining these two annular parts with the formation of an internal circular groove. outer bounding ring so that the plane of connection of these two annular parts passes through the circle described by the point of the inner circular groove farthest from the axis of symmetry of the outer bounding ring, connect the two ring-shaped parts to each other.

The proposed assembly method makes it possible to simplify the assembly of the sealing assembly and at the same time to avoid deformations of the spiral wound gasket, thereby preserving the sealing properties of the sealing assembly.

According to one embodiment of the invention, at least one groove located on one annular part on its side facing the other annular part is combined with at least one protrusion mating, said groove and located on the other annular part.

According to another embodiment of the invention, at least one annular part has through holes, and the connection of these two annular parts. performed by a detachable or one-piece connection in said through holes.

BRIEF DESCRIPTION OF THE DRAWINGS

Further, the proposed invention is described in more detail with reference to the drawings, in which:

in FIG. 1 is a front view of the assembly of the seal assembly;

in FIG. 2 is a sectional view taken along line AA of the seal assembly shown in FIG. 1, according to one embodiment of the present invention;

in FIG. 3 is a cross-sectional view along line AA of the sealing assembly shown in FIG. 1, according to another embodiment of the present invention;

in FIG. 4 is a cross-sectional view along line AA of the sealing assembly shown in FIG. 1, according to another embodiment of the present invention;

in FIG. 5 is a cross-sectional view along line AA of the sealing assembly shown in FIG. 1, according to another embodiment of the present invention;

in FIG. 6 is a partial top view B of the seal assembly shown in FIG. 5;

in FIG. 7 is a sectional view taken along line AA of the sealing assembly shown in FIG. 1, according to another embodiment of the present invention;

in FIG. 8 is a cross-sectional view along line AA of an outer restriction ring according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

In FIG. 1 shows a general front view of a sealing assembly according to the present invention. The proposed sealing assembly comprises sequentially arranged inner, restrictive ring 1, spiral-wound gasket 2 and an external restrictive ring 3. Moreover, the spiral-wound gasket 2 has an external circular protrusion 4, and the external restrictive ring 3 has an internal circular groove 5 for accommodating an external circular the protrusion 4 of the spiral wound strip 2 (Fig. 2).

In FIG. 2 shows a sectional view along line AA of the sealing assembly shown in FIG. 1, according to one embodiment of the present invention. According to this embodiment, the outer restrictive ring 3 comprises two annular parts 6 and 7 connected to each other. Each of the ring-shaped parts 6 and 7 has a chamfered surface 8 on the inside. When connecting the ring-shaped parts 6 and 7, the beveled surfaces 8 form an inner circular groove 5 of the outer delimiting ring 3. The connection plane of the ring-shaped parts 6 and 7 passes through the circle described by point 9 , which is the point of convergence of these two beveled surfaces 8 or the point farthest from the axis of symmetry of the outer restrictive ring 3.

In order to exclude the displacement of the annular parts 6 and 7 relative to each other during operation, they are mutually fixed by means of a detachable or one-piece connection.

According to one embodiment of the sealing assembly shown in FIG. 3, the mutual fixation of the ring-shaped parts 6 and 7 is carried out by spot welding performed in the circular direction of the outer limit ring 3. In FIG. 3 shows two melting zones 10 spaced apart from one another in the radial direction. However, if necessary, the number of melting zones 10 can be increased or decreased. The use of spot resistance welding allows for reliable one-piece connection of the ring-shaped parts 6 and 7.

In FIG. 4 shows another embodiment of the invention, according to which the annular parts 6 and 7 are connected by a weld seam. 11 circumferentially on the outer edge of the outer limit ring 3.

According to another embodiment of the invention illustrated in FIG. 5-6, one of the annular parts, for example, the annular part 6, contains a series of through holes 12 of a circular shape, spaced along this annular part in a circular direction. In this case, the welding of the ring-shaped parts 6 and 7 is performed in the indicated holes 12, with the formation of a weld 13.

According to another embodiment of the invention shown in FIG. 7, the integral connection of the two annular parts 6 and 7 can be made by means of a rivet connection. In this embodiment, both ring-shaped parts 6 and 7 comprise coaxial holes 14 for receiving fasteners, for example rivets (not shown). Preferably, a series of such holes are made uniformly distributed around the circumference of the outer restriction ring 3. This ensures uniform distribution of the load on the fasteners. Holes 14 can also be used to form a bolted connection (not shown).

The connection of the annular parts 6 and 7 can be carried out both at the stage of assembly of the sealing assembly in production and at the stage of direct installation of the elements of the sealing assembly in the flange connection.

In one embodiment of the invention shown in FIG. 8, one ring-shaped portion 6 may further comprise a groove 15 located on its side facing the other ring-shaped portion 7 and extending in a circular direction. In this case, the other annular part 7 may comprise a mating protrusion 16 extending in a circular direction. Said groove 15 and protrusion 16 may have a rectangular cross-section, as shown in FIG. 8, however, they may have a non-rectangular cross section, for example, a cross section in the shape of a right triangle. (not shown), one leg of which is located in the plane of connection of the ring-shaped parts 6 and 7, and the other leg is directed inside the outer restrictive ring 3. In addition, these groove 15 and the protrusion 16 can be made intermittent, that is, in the form of a set of grooves and corresponding them reciprocal protrusions. The use of the design of the outer restrictive ring 3 of the groove 15 and the protrusion 16 allows for additional mutual fixation of the annular parts 6 and 7, and thereby provide increased stability when exposed to radial forces acting on the groove 5 from the inside and tending to separate the annular parts 6 and 7 from each other . In the present embodiment, the annular parts 6 and 7 are fixed relative to each other using a circular weld 17 similar to the weld 11 described in the embodiment illustrated in FIG. four.

In addition, in some embodiments of the present invention, the annular parts 6 and 7 may be connected by means of connecting means for tightening pipe flanges with a flange connection (not shown). That is, the outer restriction ring 3 may contain a set of holes corresponding to the holes in the pipe flanges and allowing passage of the fasteners used to form the flange connection.

Circular groove. 5 preferably has a V-shape. However, the groove 5 may take any other form, allowing the invention to be realized as described in the independent claims. More specifically, the groove 5 may have, for example, a C-shape, which will allow you to assemble the sealing unit, following the similar steps of the method, which is described later in this application.

The assembly of the sealing unit is as follows. The spiral-wound gasket 2 is wound on the inner restrictive ring 1. Next, the first ring-shaped part 6 is mounted on the spiral-wound gasket 2, placing it on one side of the outer circular protrusion 4 of the spiral-wound gasket 2, and then the other ring-shaped part 7 is mounted on the other sides of the outer circular protrusion 4, combining these two annular parts 6 and 7 with the formation of the inner circular groove 5 of the outer restrictive ring 3 so that the plane of the connection of these two rings of the figurative parts passes through the circle described by the point 9 of the inner circular groove 5, the farthest from the axis of symmetry of the outer restrictive ring 3. Next, the annular parts 6 and 7 are connected to each other using a detachable or one-piece connection.

If there are a groove 15 and a protrusion 16 on the annular parts 6 and 7, described with reference to FIG. 8, when installing the annular parts 6 and 7, an additional combination of these grooves 15 and the protrusion 16 is performed.

It should be noted that the described stages of the assembly of the sealing assembly can be performed directly when installing the elements of the sealing assembly in the flanged pipe joint.

Claims (8)

1. A sealing assembly comprising sequentially arranged inner restriction ring, a spiral wound gasket having an outer circular protrusion, and an external restriction ring having an internal circular groove corresponding to the outer circular protrusion of the spiral wound gasket, characterized in that the outer restriction ring contains two ring-shaped parts made with the possibility of connection with each other, while the plane of connection of these two ring-shaped parts passes through a circle, describing taken by the point of the inner circular groove of the outer limit ring, the most distant from the axis of symmetry of the outer limit ring. 2. The sealing assembly according to claim 1, characterized in that one ring-shaped part has at least one groove located on its side facing another ring-shaped part that has at least one protrusion corresponding to said groove. 3. The sealing assembly according to claim 1, characterized in that at least one annular part has through holes for making a detachable or integral connection of said two annular parts. 4. The method of assembly of the sealing unit, which consists in winding the spiral-wound gasket on the inner ring of restriction and the subsequent installation of the outer ring on the spiral-wound gasket with the placement of the outer circular protrusion of the spiral-wound gasket in the inner circular groove of the outer ring of restriction, characterized in that use an external restrictive ring containing two annular parts made with the possibility of connection with each other, when installing an external restrictive ring, first one ring-shaped part is installed on the spiral-wound gasket, placing it on one side of the outer circular protrusion of the spiral-wound gasket, then another ring-shaped part is installed on the other side of the outer circular protrusion of the spiral-wound gasket, combining these two ring-shaped parts with the formation of an inner circular groove of the outer restrictive ring in such a way that the plane of connection of these two ring-shaped parts passes through the circle described by the point of the inner circular groove furthest from the axis of symmetry of the outer restrictive ring; these two ring-shaped parts are connected to each other. 5. The method according to p. 4, characterized in that it further combines at least one groove located on one annular part on its side facing another annular part, with at least one protrusion corresponding to the specified groove and located on the other annular parts. 6. The method according to p. 4, characterized in that at least one ring-shaped part has through holes, and the connection of these two ring-shaped parts is performed by means of a detachable or one-piece connection in the specified through holes.

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