阅读说明：本技术 一种耐高温超临界二氧化碳透平干气密封装置 (High-temperature-resistant supercritical carbon dioxide turbine dry gas sealing device ) 是由 刘光旭 黄彦平 王俊峰 于 2020-04-22 设计创作，主要内容包括：本发明提供了耐高温超临界二氧化碳透平干气密封装置,包括密封动环、密封静环和弹簧座,密封动环和密封静环组成干气密封主体且密封动环与密封静环之间的间隙能够形成刚性气膜；密封静环与弹簧座之间通过第一C型密封圈密封,弹簧座与透平气缸之间通过弹簧连接且通过第二C型密封圈密封,第一C型密封圈和第二C型密封圈表面涂覆有耐高温涂层且内部为金属材质。本发明采用表面带耐高温涂层的金属C型密封圈替代传统干气密封中耐高温性能差的聚四氟密封圈,利用金属C型密封圈承压能力强、耐高温性能好且具有弹性,耐高温涂层润滑性好、滑动跟随性能佳的特性,实现透平转子高转速下干气密封微小振动补偿,实现超临界二氧化碳透平端部密封。(The invention provides a high-temperature-resistant supercritical carbon dioxide turbine dry gas sealing device which comprises a sealing movable ring, a sealing static ring and a spring seat, wherein the sealing movable ring and the sealing static ring form a dry gas sealing main body, and a rigid gas film can be formed in a gap between the sealing movable ring and the sealing static ring; seal through first C type sealing washer between quiet ring of seal and the spring holder, through spring coupling and through second C type sealing washer sealed between spring holder and the turbine cylinder, first C type sealing washer and second C type sealing washer surface coating have high temperature resistant coating and inside be the metal material. According to the invention, the metal C-shaped sealing ring with the high-temperature-resistant coating on the surface is adopted to replace a polytetrafluoroethylene sealing ring with poor high-temperature resistance in the traditional dry gas sealing, and the characteristics of strong bearing capacity, good high-temperature resistance, elasticity, good lubricating property and good sliding following performance of the metal C-shaped sealing ring are utilized to realize dry gas sealing micro vibration compensation of the turbine rotor at high rotating speed, so that the end part of the supercritical carbon dioxide turbine is sealed.)

1. A high-temperature-resistant supercritical carbon dioxide turbine dry gas sealing device is characterized by comprising a sealing movable ring, a sealing static ring and a spring seat,

the seal dynamic ring and the seal static ring form a dry gas seal main body, and a gap between the seal dynamic ring and the seal static ring can form a rigid gas film;

the static sealing ring and the spring seat are sealed through a first C-shaped sealing ring, and the spring seat is connected with the turbine cylinder through a spring and sealed through a second C-shaped sealing ring;

the surfaces of the first C-shaped sealing ring and the second C-shaped sealing ring are coated with high-temperature-resistant coatings, and the interiors of the first C-shaped sealing ring and the second C-shaped sealing ring are made of metal materials.

2. The high temperature tolerant supercritical carbon dioxide turbine dry gas seal of claim 1 wherein the dry gas seal is disposed at an end of a turbine cylinder.

3. The high temperature tolerant supercritical carbon dioxide turbine dry gas seal of claim 1 wherein the dry gas seal is in gas phase communication with an upstream high pressure seal.

4. The high temperature resistant supercritical carbon dioxide turbine dry gas sealing device of claim 1, wherein the surfaces of the first and second C-shaped sealing rings are coated with SiC coatings and the interior of each of the first and second C-shaped sealing rings is 00Cr17Ni12Mo2 material.

5. The high temperature resistant supercritical carbon dioxide turbine dry gas sealing device according to claim 1, wherein the first C-shaped sealing ring and the second C-shaped sealing ring are installed with openings facing away from the sealing moving ring, and the turbine cylinder is provided with a U-shaped clamping groove to position the C-shaped sealing ring to facilitate installation and limiting of the C-shaped sealing ring.

Technical Field

The invention relates to the technical field of advanced turbine equipment, in particular to a high-temperature-resistant supercritical carbon dioxide turbine dry gas sealing device.

Background

The supercritical carbon dioxide power generation system is a Brayton cycle system which takes carbon dioxide in a supercritical state as a working medium, and the cycle process is as follows: firstly, boosting the pressure of supercritical carbon dioxide by a compressor; then, isobaric heating is carried out on the working medium by using a heat exchanger; secondly, the working medium enters a turbine to push a turbine to do work, and the turbine drives a motor to generate electricity; and finally, the working medium enters the cooler to recover to an initial state and then enters the compressor to form closed circulation. Wherein, when the temperature of the carbon dioxide reaches 31.10C and the pressure reaches 7.38MPa, the carbon dioxide is changed into a supercritical state, and the carbon dioxide has the special physical characteristics of small gas viscosity and large liquid density, so that the carbon dioxide has the characteristics of good fluidity, high heat transfer efficiency, compressibility and the like.

The turbine is the core equipment of the supercritical carbon dioxide power system, and the operating temperature is usually above 400 ℃. As the lubricating property of carbon dioxide is obviously weaker than that of water, the mechanical sealing mode adopted in the traditional steam turbine cannot be used for the supercritical carbon dioxide turbine, and the current domestic and foreign research results show that dry gas sealing is the preferred scheme for shaft end sealing of the high-power supercritical carbon dioxide turbine. The existing dry gas seal mainly aims at the medium-low temperature service environment, the seal ring of the seal is mainly made of polytetrafluoroethylene, and the polytetrafluoroethylene seal ring is difficult to bear the high-temperature environment formed by the heat conduction of a turbine cylinder, so that the existing dry gas seal structure is difficult to meet the application requirement of the high-temperature working condition of a supercritical carbon dioxide turbine, and the research and development of a high-efficiency and reliable high-temperature resistant turbine shaft end seal structure is the key of the research and development of the supercritical carbon dioxide turbine.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a dry gas sealing device capable of realizing the supercritical carbon dioxide turbine shaft end sealing under the high-temperature condition.

The invention provides a high-temperature-resistant supercritical carbon dioxide turbine dry gas sealing device, which realizes the end sealing of a turbine cylinder and comprises a sealing movable ring, a sealing static ring and a spring seat, wherein the sealing movable ring is fixed on a turbine rotor, the sealing static ring is fixed on the turbine cylinder, the spring seat is fixed on the turbine cylinder and allows the axial sliding along the turbine rotor, wherein,

the seal dynamic ring and the seal static ring form a dry gas seal main body, and a gap between the seal dynamic ring and the seal static ring can form a rigid gas film;

the static sealing ring and the spring seat are sealed through a first C-shaped sealing ring, and the spring seat is connected with the turbine cylinder through a spring and sealed through a second C-shaped sealing ring;

the surfaces of the first C-shaped sealing ring and the second C-shaped sealing ring are coated with high-temperature-resistant coatings, and the interiors of the first C-shaped sealing ring and the second C-shaped sealing ring are made of metal materials.

According to one embodiment of the high temperature resistant supercritical carbon dioxide turbine dry gas seal device of the present invention, the dry gas seal device is disposed at an end of a turbine cylinder.

According to one embodiment of the high temperature resistant supercritical carbon dioxide turbine dry gas seal of the present invention, the dry gas seal is in gas phase communication with an upstream high pressure seal.

According to one embodiment of the dry gas sealing device of the high-temperature-resistant supercritical carbon dioxide turbine, the surfaces of the first C-shaped sealing ring and the second C-shaped sealing ring are coated with SiC coatings, and the interior of the first C-shaped sealing ring and the second C-shaped sealing ring are made of 00Cr17Ni12Mo2 materials.

According to an embodiment of the dry gas sealing device for the high-temperature-resistant supercritical carbon dioxide turbine, the first C-shaped sealing ring and the second C-shaped sealing ring are installed in a mode that the openings of the first C-shaped sealing ring and the second C-shaped sealing ring are opposite to the sealing movable ring, and the turbine cylinder is provided with a U-shaped clamping groove for positioning the C-shaped sealing ring so as to facilitate installation and limiting of the C-shaped sealing ring.

Compared with the conventional scheme, the 00Cr17Ni12Mo2 metal C-shaped sealing ring with the high-temperature-resistant coating on the surface in the high-temperature-resistant supercritical carbon dioxide turbine dry gas sealing device replaces a polytetrafluoroethylene sealing ring with poor high-temperature resistance in the traditional dry gas sealing, and the characteristics of strong bearing capacity, good high-temperature resistance, certain elasticity, good lubricating property of the high-temperature-resistant coating and good sliding following performance of the metal C-shaped sealing ring are utilized to realize the high-speed dry gas sealing micro vibration compensation of a turbine rotor and realize the end sealing of a supercritical carbon dioxide turbine under the high-temperature and high-pressure conditions.

Drawings

Fig. 1 shows a schematic structural view of a high temperature resistant supercritical carbon dioxide turbine dry gas seal according to an exemplary embodiment of the present invention.

FIG. 2 is an enlarged partial structural view of the periphery of a first C-shaped sealing ring in a dry gas seal of a high temperature resistant supercritical carbon dioxide turbine according to an exemplary embodiment of the present invention.

FIG. 3 is an enlarged partial structural view of the periphery of a second C-shaped seal ring in a dry gas seal of a high temperature resistant supercritical carbon dioxide turbine according to an exemplary embodiment of the present invention.

FIG. 4 is a schematic diagram of a C-ring configuration in a high temperature resistant supercritical carbon dioxide turbine dry gas seal according to an exemplary embodiment of the present invention.

Description of reference numerals:

the device comprises a sealing movable ring 1, a sealing static ring 2, a first C-shaped sealing ring 3, a spring seat 4, a second C-shaped sealing ring 5, a turbine cylinder 6, a surface coating 7 and a metal substrate 8.

Detailed Description

All of the features disclosed in this specification, or all of the steps in any method or process so disclosed, may be combined in any combination, except combinations of features and/or steps that are mutually exclusive.

Any feature disclosed in this specification may be replaced by alternative features serving equivalent or similar purposes, unless expressly stated otherwise. That is, unless expressly stated otherwise, each feature is only an example of a generic series of equivalent or similar features.

Fig. 1 shows a schematic structural view of a high temperature resistant supercritical carbon dioxide turbine dry gas seal according to an exemplary embodiment of the present invention.

As shown in fig. 1, according to an exemplary embodiment of the present invention, the high temperature resistant supercritical carbon dioxide turbine dry gas sealing device includes a sealing dynamic ring 1, a sealing static ring 2 and a spring seat 4, wherein the sealing dynamic ring is fixed on a turbine rotor, the sealing static ring is fixed on a turbine cylinder, and the spring seat is fixed on the turbine cylinder and allows axial sliding along the turbine rotor. The dry gas seal is provided at the end of the turbine cylinder 6 to effect an end seal and is in gas phase communication with the upstream high pressure seal. Wherein, sealed rotating ring 1 and sealed quiet ring 2 constitute the sealed main part of dry gas and the clearance between sealed rotating ring 1 and the sealed quiet ring 2 can form the rigidity air film, realizes sealed moving seal between the quiet ring.

When the sealing moving ring 1 with the hydrodynamic groove arranged on the outer side of the end face rotates, the hydrodynamic groove pumps high-pressure isolation gas on the outer diameter side (called as the upstream side) into a space between the sealing end faces, and a thin gas film is formed between the sealing moving ring 1 and the sealing static ring 2, so that the formed gas film can completely block a relatively low-pressure sealing medium leakage channel when the sealing works in a non-contact state, and zero leakage or zero escape of a sealing medium is realized.

Fig. 2 is a partial structural enlarged view illustrating a periphery of a first C-shaped seal ring in a high temperature resistant supercritical carbon dioxide turbine dry airtight device according to an exemplary embodiment of the present invention, and fig. 3 is a partial structural enlarged view illustrating a periphery of a second C-shaped seal ring in a high temperature resistant supercritical carbon dioxide turbine dry airtight device according to an exemplary embodiment of the present invention.

As shown in fig. 2 and 3, the stationary seal ring 2 is sealed with the spring seat 4 through the first C-shaped seal ring 3, the spring seat 4 is connected with the turbine cylinder 6 through a spring and sealed through the second C-shaped seal ring 5, the spring seat 4 is provided with a U-shaped clamping groove with a leftward opening, the turbine cylinder 6 is provided with a U-shaped clamping groove with a downward opening, and the U-shaped clamping groove is used for positioning in the installation process of the C-shaped seal ring and limiting in the operation process. Wherein, first C type sealing washer and second C type sealing washer surface coating have high temperature resistant coating and inside be the metal material, adopt the metal C type sealing washer of the high temperature resistant coating of surface area, can ensure that the sealing washer has good slip following performance, and the elasticity effect of metal sealing washer can be ensured and sealed effect is ensured to C type structure sealing washer.

FIG. 4 is a schematic diagram of a C-ring configuration in a high temperature resistant supercritical carbon dioxide turbine dry gas seal according to an exemplary embodiment of the present invention.

As shown in FIG. 4, the surface coating 7 of the first C-shaped sealing ring 3 is set to be a SiC coating, the inner metal matrix 8 is set to be 00Cr17Ni12Mo2, and the high-temperature environment formed by the heat conduction of the turbine rotor can be borne, so that the sealing between the static sealing ring 2 and the spring seat 4 is realized; the surface coating 7 of the second C-shaped sealing ring 5 is also set to be a SiC coating, the inner metal matrix 8 is set to be 00Cr17Ni12Mo2, and the high-temperature environment formed by heat conduction of the turbine cylinder can be borne, so that sealing between the turbine cylinder 6 and the spring seat 4 is realized. The C-shaped sealing ring made of the metal material has the characteristics of strong bearing capacity, good high-temperature resistance, certain elasticity, good lubricity of the SiC high-temperature-resistant coating and good sliding following performance, can meet the requirement of dry-gas sealing micro-vibration compensation of the turbine rotor at a high rotating speed, and finally realizes the end sealing of the supercritical carbon dioxide turbine under the conditions of high temperature and high pressure.

As shown in fig. 1, the first C-ring 3 and the second C-ring 5 are preferably mounted with the openings facing away from the sealing moving ring 1. Moreover, the metal material of the first C-shaped sealing ring and the second C-shaped sealing ring is 00Cr17Ni12Mo2 metal, SiC coatings are respectively attached to the surfaces of the first C-shaped sealing ring and the second C-shaped sealing ring, and the sealing requirements are met under the condition that the mechanical performance requirements are met.

The invention is further described below by means of specific examples.

As shown in fig. 1, the present invention includes a movable sealing ring 1, a stationary sealing ring 2, a first C-shaped sealing ring 3, a spring seat 4, and a second C-shaped sealing ring 5. The seal movable ring and the seal static ring form a dry gas seal main body, and a rigid gas film is formed in a gap between the seal movable ring and the seal static ring to realize sealing between the seal movable ring and the seal static ring. The surface of the first C-shaped sealing ring 3 is a SiC coating, and the interior of the first C-shaped sealing ring is made of 00Cr17Ni12Mo2 metal, so that the high-temperature environment formed by the heat conduction of a turbine rotor can be borne, and the sealing between the static sealing ring and the spring seat is realized; the second C-shaped sealing ring 5 is shown as a SiC coating, the interior of the second C-shaped sealing ring is made of 00Cr17Ni12Mo2 metal, and the second C-shaped sealing ring can bear the high-temperature environment formed by the heat conduction of the turbine cylinder and realize the sealing between the turbine cylinder and the spring seat. The sealing ring is a C-shaped sealing ring made of 00Cr17Ni12Mo2 metal with the SiC coating 8, and dry gas sealing micro-vibration compensation of the turbine rotor at high rotating speed is realized by utilizing the characteristics of stronger bearing capacity, good high temperature resistance, certain elasticity, good lubricating property and good sliding following performance of the metal C-shaped sealing ring, and the end sealing of the supercritical carbon dioxide turbine under the conditions of high temperature and high pressure.

The invention is not limited to the foregoing embodiments. The invention extends to any novel feature or any novel combination of features disclosed in this specification and any novel method or process steps or any novel combination of features disclosed.