CN206338514U - A flange sealing structure suitable for simultaneously bearing internal and external pressure - Google Patents

Abstract

This novel seal structure that belongs to, concretely relates to flange seal structure suitable for bear inside and outside pressure simultaneously. The utility model provides a flange seal structure suitable for bear inside and outside pressure simultaneously, includes that needs sealed flange one and flange two are equipped with two recesses on flange one towards flange two's terminal surface, and one of them recess is close to flange one's center, and another recess is close to flange one's edge, sets up opening metal C type circle inwards in the recess that is close to the center, sets up opening metal C type circle outwards in another recess. This neotype effect that is showing is: the flange sealing structure simultaneously adopts the metal C-shaped ring with the outward opening and the inward opening, so that the metal C-shaped ring can bear the internal pressure and the external pressure simultaneously, has the characteristic of self-tightening sealing, and is more reliable in sealing due to higher pressure.

Description

A flange sealing structure suitable for simultaneously bearing internal and external pressure

technical field

The utility model belongs to a sealing structure, and in particular relates to a flange sealing structure suitable for bearing internal and external pressure at the same time.

Background technique

Pipeline transportation is a way of using pipelines to transport liquid or gas. It is not only widely used in all walks of life in industry, such as petrochemical, mining and metallurgy, chemical raw materials, thermal power and nuclear power, etc.; it is also closely related to people's lives, such as tap water, natural gas, etc. delivery. A large number of pipeline connections in pipeline transportation adopt flange sealing structures. With the rapid development of industry, higher requirements are put forward for the sealing of pipelines. In some special installation environments and some special working conditions, pipelines are required to be sealed. At the same time, it can withstand internal and external pressure, which puts forward higher requirements for the sealing of pipelines and pipeline components.

There are rich oil and mineral resources buried deep in the sea. Human beings have gradually laid pipelines deep in the sea. The sealing of pipelines must not only withstand the internal pressure of the medium, but also withstand the deep external pressure; When an accident occurs in a nuclear power plant, it needs to withstand immersion conditions. The pipeline and valves are immersed in the liquid as a whole, withstand a certain external pressure, and also withstand severe temperature fluctuations. The ordinary flange gasket structure does not consider the external pressure, and it is easy to be squeezed by the external pressure to cause leakage. The leakage of the delivery pipeline often causes serious consequences. In these special installation environments and operating conditions that are under internal and external pressure at the same time, a more reliable sealing structure is urgently needed.

Contents of the invention

The purpose of this new model is to provide a flange sealing structure suitable for simultaneously bearing internal and external pressure in view of the defects of the prior art. The structure is equipped with metal C-rings with openings facing inwards and outwards at the same time, which can withstand internal and external pressure and form a good and reliable seal.

The technical scheme of the present invention is: a flange sealing structure suitable for bearing internal and external pressure at the same time, including the connecting flange 1 and the connecting flange 2 that need to be sealed, and the end surface of the connecting flange 1 facing the connecting flange 2 is provided with Two grooves, one of which is close to the center of the connecting flange 1, and the other groove is close to the edge of the connecting flange 1. A metal C-ring with an opening facing inward is set in the groove near the center, and a metal C-ring is provided in the other groove A metal C-ring with an opening facing outward is arranged inside.

A flange sealing structure suitable for bearing internal and external pressure as described above, wherein, the side of the connecting flange 2 facing the connecting flange 1 is a plane near the inner side of the edge groove of the connecting flange 1, and the A slope is provided on the outer part of the connecting flange-edge groove.

The above-mentioned flange sealing structure suitable for bearing internal and external pressure at the same time, wherein a positioning groove is provided on the innermost side of the connecting flange 1, and a positioning boss corresponding to the positioning groove is provided on the connecting flange 2.

The remarkable effect of the new model is: the flange sealing structure adopts the metal C-shaped ring with the opening facing outward and the opening facing inward at the same time, which can bear the internal and external pressure at the same time, and the metal C-ring has the characteristics of self-tight sealing. The higher the pressure, the better the sealing effect. The more reliable; the two metal C-rings form a double sealing guarantee, even if the sealing performance of the metal C-ring with the inner opening facing inward is reduced and a certain leakage occurs, the metal C-ring with the opening facing outward can also provide a certain internal pressure seal. And vice versa; it has a thermal expansion compensation structure, the inner side of the flange surface is designed with a gap, and the outer side is designed with a slope, which avoids the sealing failure caused by the thermal expansion of the flange caused by the temperature difference between the inner and outer media.

Description of drawings

Fig. 1 is a schematic diagram of a flange sealing structure suitable for simultaneously bearing internal and external pressure provided by the present invention;

Figure 2 is a schematic diagram of the thermal expansion compensation structure inside the flange;

Figure 3 is a schematic diagram of the thermal expansion compensation structure outside the flange;

In the figure, 1 metal C-ring with an opening facing inward; 2 metal C-ring with an opening facing outward; 3 connecting flange 1; 4 connecting flange 2; 5 studs; 6 nuts; 9 The outer flange expands when heated.

detailed description

A flange sealing structure suitable for bearing internal and external pressure at the same time, which includes: metal C-shaped ring 1 with an opening facing inward, metal C-ring 2 with an opening facing outward, connecting flange 1 3, connecting flange 2 4, and studs 5 , Nut 6. The entire flange sealing structure is suitable for the connection between the conveying pipelines, and also suitable for the body cover connection of pipeline components such as valves. There are two grooves designed on the flange plane of the connecting flange 1, which are respectively used to install the metal C-shaped ring 1 with the opening facing inward and the metal C-shaped ring 2 with the opening facing outward, wherein the metal C-shaped ring 1 with the opening facing inward is installed on The inner mounting groove is used to withstand internal pressure; the metal C-ring 2 with the opening facing outward is installed in the outer mounting groove to withstand external pressure. The cross-sectional diameter of the metal C-ring can be selected according to the internal and external pressure. The higher the pressure level, the metal The section of the C-ring is larger. Connecting flange 1 3 and connecting flange 2 4 are connected by studs and nuts. After the nuts are pre-tightened, the flange planes of the two flanges are in contact, and the two metal C-rings are compressed to be flush with the installation groove to establish a sealing specific pressure. , forming a good seal.

The innermost side of the connecting flange 3 is designed with a positioning groove, and the corresponding inner side of the connecting flange 2 4 is designed with a positioning boss, which extends into the positioning groove of the connecting flange 1 3 during installation. Clearance. The flange surface of the connecting flange 2 4 is designed as a plane corresponding to the positions of the two metal C-shaped rings, and the outer side is designed with a certain slope. The gap on the inside and the slope on the outside form a thermal expansion compensation structure.

A flange sealing structure suitable for bearing internal and external pressure at the same time. It is equipped with metal C-shaped rings with openings facing inwards and outwards at the same time, which can withstand internal and external pressures at the same time and form a good and reliable seal.

Realize the technical characteristic of this new type to have:

(1) Use a metal C-ring

Metal C-ring is a new type of sealing element, which is more and more used in occasions with high sealing requirements and has many advantages. The sealing structure uses a spring-reinforced metal C-ring with a built-in metal spring. There is a layer of metal coating on the outside of the spring, and the outermost layer is silver-plated or silver-coated. The advantages of the metal C-ring are: the installation space is small, and the design is easier to realize; the seal is made of metal as a whole, which is more suitable for harsh environments such as radiation, humidity and heat; the built-in spring, compared with the metal O-ring of the same diameter, has More excellent springback and better sealing performance; the metal C-shaped ring is designed with an opening, the cross-section is like a letter C, and the opening direction faces the medium, which has the function of self-tightening sealing. The higher the pressure, the better the sealing performance; at the same time, the metal C The ring maintains excellent sealing performance under pressure fluctuations.

(2) Double circle design

The flange sealing structure is equipped with 2 metal C-rings, one opening faces inward, and the other opening faces outwards. The metal C-ring with the opening facing inward is installed in the installation groove of the inner ring to withstand internal pressure; the metal C-ring with the opening facing outward The ring is installed in the mounting groove of the outer ring to withstand external pressure. The openings of the two metal C-rings face the inner and outer media respectively, exerting the self-tight sealing effect of the metal C-rings, and the sealing performance is excellent; further, the two metal C-rings form a double sealing guarantee, even if the opening of the inner ring faces inward The sealing performance of the metal C-ring decreases to produce a certain leakage, and the metal C-ring with the opening facing outward can also provide a certain internal pressure seal, and vice versa, the two metal C-rings bear internal and external pressure at the same time, double protection, good and reliable sealing .

(3) Thermal expansion compensation structure

When the pipeline or pipeline components are subjected to internal and external pressure at the same time, the temperature of the medium inside and outside is often different, which is likely to cause uneven heating and deformation of the flange, resulting in leakage. The flange sealing structure has a thermal expansion compensation structure design, which provides a more stable and reliable sealing. When the temperature of the internal medium is higher than that of the external medium, the inner side of the flange will expand when heated, and the gap between the positioning groove and the positioning boss can compensate the expansion of the flange, and the sealing surface of the metal C-ring is still in effective contact to achieve sealing. If there is not enough clearance between the groove and the positioning boss, the metal C-ring faces the risk of the sealing surface being disengaged and the seal failure, see diagram 2; when the temperature of the external medium is higher than that of the internal medium, the outer side of the flange will expand when heated, and the flange surface will The designed slope can compensate for the expansion of the flange, and the sealing surface of the metal C-ring is still in effective contact to achieve sealing. If the two flanges are in flat contact as a whole, the metal C-ring faces the risk of the sealing surface detaching and sealing failure. See Schematic 3. The anti-expansion and contraction design can always keep the metal C-ring in contact with the flange surface to achieve reliable sealing.

Claims (3)

1. A flange sealing structure suitable for bearing internal and external pressure at the same time, characterized in that: it includes connecting flange one (3) and connecting flange two (4) that need to be sealed, and the connecting flange one (3) faces the connection There are two grooves on the end face of flange two (4), one of which is close to the center of connecting flange one (3), and the other groove is close to the edge of connecting flange one (3). A metal C-shaped ring (1) with an opening facing inward is arranged in the groove, and a metal C-shaped ring (2) with an opening facing outward is arranged in the other groove. 2. A flange sealing structure suitable for simultaneously bearing internal and external pressure as claimed in claim 1, characterized in that: the side of the connecting flange two (4) facing the connecting flange one (3), close to the connection method The part inside the edge groove of the flange one (3) is a plane, and the part near the outside of the edge groove of the connecting flange one (3) is provided with a slope. 3. A flange sealing structure suitable for simultaneously bearing internal and external pressure as claimed in claim 2, characterized in that: a positioning groove is provided on the innermost side of the connecting flange one (3), and a positioning groove is provided on the connecting flange two (4) ) is provided with a positioning boss corresponding to the positioning groove.