CN115539732A - Double-energy-storage wave tooth gasket - Google Patents

Abstract

The invention discloses a double-energy-storage corrugated-tooth gasket, which comprises a metal skeleton and expanded graphite. The upper and lower surfaces of the metal skeleton are provided with mutually staggered concentric circular grooves distributed evenly at intervals, and the upper and lower surfaces of the metal skeleton are compounded. A layer of expanded graphite together forms a double energy storage wave-tooth gasket, and the upper and lower surfaces of the metal skeleton form corrugated sharp-tooth crests that are alternately distributed with the concentric circular grooves. The double-energy-storage corrugated-tooth gasket of the present invention has large energy storage, large compression rebound rate, frequent temperature changes of the heat exchanger, large thermal expansion and cold contraction, and large compensation amount of the energy storage gasket, which can compensate for the flange surface gap caused by the cold contraction of the equipment. , the sealing effect is better, the service life is longer, and the leakage caused by frequent temperature changes of the heat exchanger is prevented.

Description

A double energy storage corrugated tooth gasket

technical field

The invention relates to the technical field of gaskets, which are used for the sealing function of shell-and-tube heat exchangers and flange connections, in particular to a double-energy-storage wave-tooth gasket.

Background technique

The gasket is made of asbestos board, rubber board or steel plate, etc., and is placed between two planes to strengthen the sealing material. In order to prevent fluid leakage, the sealing element is arranged between the static sealing surfaces. In the shell and tube heat exchanger, Ordinary gaskets have a small rebound rate during sealing in flange connections, and the temperature of the heat exchanger changes frequently.

Contents of the invention

The object of the present invention is to provide a double-energy-storage corrugated-tooth gasket to solve the problems raised in the above-mentioned background technology.

In order to achieve the above object, the present invention provides the following technical solution: a double-energy-storage wave-tooth gasket, including a metal skeleton and expanded graphite, and the upper and lower surfaces of the metal skeleton are provided with concentric circular grooves that are evenly spaced and staggered from each other The upper and lower surfaces of the metal frame are combined with a layer of expanded graphite to form a double energy-storage wave-tooth gasket. The upper and lower surfaces of the metal frame form corrugated peaks that are alternately distributed with the concentric circular grooves.

Compared with the prior art, the present invention has the following beneficial effects:

The double-energy-storage corrugated-tooth gasket of the present invention has large energy storage, large compression rebound rate, frequent temperature changes of the heat exchanger, large thermal expansion and cold contraction, and large compensation amount of the energy storage gasket, which can compensate for the flange surface gap caused by the cold contraction of the equipment. , the sealing effect is better, the service life is longer, and the leakage caused by frequent temperature changes of the heat exchanger is prevented.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required in the embodiments. Obviously, the accompanying drawings in the following description are only some of the present invention. Embodiments, for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without any creative effort.

Figure 1 is a schematic diagram of a double-energy-storage corrugated-tooth gasket.

Fig. 2 is a comparison test diagram of the sealing performance of the double metal self-sealing corrugated tooth composite gasket and the flexible graphite metal corrugated tooth composite gasket according to the embodiment of the present invention.

Reference signs:

1. Metal skeleton; 2. Expanded graphite; 3. Concentric circular grooves; 4. Corrugated peaks.

detailed description

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, not all of them. Based on The embodiments of the present invention and all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Please refer to Fig. 1, a double-energy-storage wave-tooth gasket according to an embodiment of the present invention includes a metal skeleton 1 and expanded graphite 2, and the upper and lower surfaces of the metal skeleton 1 are provided with concentric Circular groove, so that the tooth has its own spring function 3, and the upper and lower layers of the metal skeleton are combined with a layer of expanded graphite 2 to form a double energy storage corrugated tooth gasket. The upper and lower surfaces of the metal skeleton 1 form concentric circles The grooves 3 are alternately distributed with corrugated tine peaks 4 .

Since the double-energy-storage wave-tooth gasket has the dual functions of tooth-shaped metal seal and non-metallic expanded graphite seal, and its sealing belt is completely separated, it has particularly good sealing performance. Due to the double-energy-storage wave-tooth gasket The sheet has a corrugated elastic skeleton with a special structure, and the metal skeleton 1 and expanded graphite 2 that constitute the gasket have excellent high temperature resistance, fluid erosion resistance, and will not age. The elasticity of the gasket is mainly composed of metal with a special structure. The skeleton is formed, so there is no need to worry about stress relaxation during use, so it can maintain excellent sealing performance for a long time. When the double energy-storage corrugated tooth gasket is used, the corrugated tooth peak 4 of the metal skeleton 1 is in close contact with the flange surface, and its expanded graphite The material-fixed metal skeleton and the flange surface are closed, so there is no need to worry about the expanded graphite material being washed away by the high-pressure fluid.

Working principle: Due to the compression of the flange during use, the expanded graphite compounded on the metal skeleton is compressed into the concentric circular groove 3, and the ring-shaped corrugated peaks 4 on the upper and lower surfaces of the metal skeleton are in close contact with the flange surface and Under the further compression of the flange, elastic deformation occurs, so that the expanded graphite is highly compressed and sealed in the annular airtight space formed between the metal skeleton and the flange surface, thus forming the unique performance of the corrugated tooth composite gasket. The corrugated sharp tooth peaks 4 of the metal skeleton and the highly compressed expanded graphite material form a tight seal. The whole composite gasket actually has the combined effect of multiple metal seals and expanded graphite material seals. And the specially constructed metal skeleton is like an elastic element, which makes the corrugated tooth composite gasket have good elasticity.

The installation preload of the double energy storage corrugated tooth gasket is the same as that of other gaskets. It is tightly pressed between the two flanges through the connecting bolts, and the corresponding gasket preload stress is formed on the surface of the gasket. In the operating state, when the pressure medium enters the equipment or pipeline, the initial pre-tightening stress of the gasket will drop due to various reasons. For example, pressure entering the system creates a corresponding axial force between the two flanges. This axial force will change both the bolt force and the original gasket stress in the flange connection. The bolt force will increase with the increase of the internal pressure, while the initial pre-tightening stress of the gasket will decrease with the increase of the internal pressure. Another example is the reduction of the pre-tightening stress of the gasket caused by the uncoordinated deformation of the flange and the bolt caused by the fluctuation of the medium temperature, or the creep relaxation characteristics of the gasket itself, which will reduce the pre-tightening stress of the gasket. Therefore, in the operating state, for ordinary gaskets generally designed according to the principle of "forced sealing", the reduction of the original pre-tightening stress of the gasket will inevitably lead to a decrease in the sealing ability of the gasket. When the stress of the gasket drops to a certain level, it will There will be obvious leaks. However, it is different for the double-energy-storage wave-tooth gasket designed according to the principle of "pressure self-sealing". Although the stress of each component is the same as that of "forced seal" under preload, when the pressure medium enters the system, it will penetrate into the microscopic gap between the two metal sheets of the metal frame at the same time under the operating state. Since the outer circumferences of the upper and lower metal sheets of the superimposed metal skeleton have been completely and tightly fused together, the medium will not leak out from here. The pressure of the medium entering the microscopic gap between the two metal sheets acts on the inner surfaces of the two metal sheets, causing the two metal sheets to press outwards to the corresponding flange surfaces, so that the upper and lower outer surfaces of the double energy storage corrugated tooth gasket and the Additional gasket stress is created between the flange faces. This additional gasket stress exists with the medium pressure, and its value can reach the pressure value of the medium. That is to say, in the operating state, the gasket stress of the double-energy-storage corrugated-tooth gasket always has an additional stress compared with the ordinary gasket, and its value can be equivalent to the medium pressure. The existence of this additional stress compensates or increases the gasket stress that was originally reduced due to pressure rise or other reasons, so that the double-energy-storage corrugated-tooth gasket has a higher performance than other existing gaskets (including the current excellent performance and The widely used flexible graphite metal corrugated composite gasket) has better sealing performance. Even in extreme cases, even if the initial pre-tightening stress of the double-energy-storage wave-tooth gasket is lost due to various reasons, the gasket still has the same additional gasket stress as the medium pressure, so that the gasket can still maintain a certain tightness.

In order to verify the sealing characteristics of the double-energy-storage wave-tooth gasket, especially its "pressure self-sealing" performance, we selected a bimetallic self-sealing wave-tooth composite gasket (that is, a double-energy-storage wave-tooth gasket) and ordinary flexible graphite Metal corrugated composite gaskets were tested for sealing performance comparison. In order to better observe the "pressure self-sealing" performance of the gasket, this test is carried out with a low preload stress, so that when the internal pressure rises and the gasket stress is further reduced, the sealing of the gasket under this condition can be observed and measured sex.

As shown in Figure 2, it can be seen from the tabulated data that the pre-tightening stress of the gasket is very low (the pre-tightening stress of the energy-storage self-sealing corrugated tooth composite gasket is 1.4MPa, while the ordinary flexible graphite metal corrugated tooth composite gasket The pre-tightening stress is 2.1MPa), and when the pressure of the sealed medium is high (2.OMP), the energy storage self-sealing corrugated tooth composite gasket can still keep the seal tight, while the ordinary flexible graphite metal corrugated tooth composite gasket Gaskets have developed larger leak rates.

According to the general sealing theory, it is difficult to achieve sealing when the stress of the gasket is small, especially when the stress of the gasket is less than the pressure of the medium to be sealed. Therefore, in this test, it is not surprising that ordinary flexible graphite metal corrugated composite gaskets have leakage. But also under low stress, the energy storage self-sealing corrugated tooth composite gasket can maintain good sealing performance, which shows that there is a different stress state on the gasket than ordinary flexible graphite metal corrugated tooth composite gasket. According to the previous analysis of the structural characteristics and working principle of the energy storage self-sealing corrugated tooth composite gasket, in the presence of medium pressure, the actual gasket stress between the gasket surface and the flange surface is not like other ordinary gaskets. Gaskets only have the preloaded residual stress, but the sum of the preloaded residual stress and the internal pressure of the medium. This stress is always higher than the medium pressure. This explains why ordinary flexible graphite metal corrugated tooth composite gaskets cannot seal under the above test conditions, while energy storage self-sealing corrugated tooth composite gaskets can still obtain good sealing performance under the same conditions. It can be seen that the sealing performance of the energy storage self-sealing corrugated tooth composite gasket not only depends on the pretightening force of the gasket, but also depends on the pressure of the medium to be sealed, which is the principle of the so-called "pressure self-sealing". This also fully demonstrates that the energy-storage self-sealing wave-tooth composite gasket can obtain good sealing performance even when the preload stress is reduced by relying on the medium pressure.

Finally, it should be noted that: the above is only a preferred embodiment of the present invention, and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, it still The technical solutions recorded in the foregoing embodiments may be modified, or some technical features thereof may be equivalently replaced. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (1)

1. The utility model provides a two energy storage ripples tooth gaskets, includes metal framework and expanded graphite, its characterized in that, open the upper and lower surface of metal framework has the concentric circles slot of the even interval distribution that staggers each other, and the upper and lower compound one deck expanded graphite of metal framework forms two energy storage ripples tooth gaskets jointly, the upper and lower surface of metal framework form with the ripple cusp crest of concentric circles slot distribution in turn.

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