A method for explosion-proofing the ceramic valve core of a pneumatic hard-sealed ceramic hemispherical valve

Abstract

The present invention discloses a pneumatic hard-sealed ceramic hemispherical valve ceramic valve core explosion-proof method, comprising the following steps, S1: disc spring selection analysis stage: S11: according to the minimum preload specific pressure required by the disc spring, and the size of the ball, ceramic valve body, and ceramic base, first try to take a group of disc springs and measure the size of the disc springs. The pneumatic hard-sealed ceramic hemispherical valve ceramic valve core explosion-proof method calculates the disc springs of suitable sizes for different types of ceramic hemispherical valves through formulas, and installs the disc springs between valve components, so that there are disc springs between the valve components as compensation parts, which can effectively compensate when the valve components act, and improve the grinding and self-cleaning function of the ceramic valve ceramic sealing surface during the switching process, thereby solving the valve jamming caused by foreign matter adhering to the valve core surface, thereby avoiding the problem of ceramic valve core bursting caused by repeated use of the jammed valve, and extending the service life of the valve.

Description

Technical Field

[0001] The invention relates to the technical field of blast furnace smelting, in particular to an explosion-proof method for a ceramic valve core of a pneumatic hard-sealed ceramic hemispherical valve. Background Art

[0002] In the process of recovering byproduct gas produced by blast furnace smelting in the metallurgical industry, the blast furnace gas enters the purification system after rough dust removal by gravity dust removal, and is recycled after fine dust removal by dry dust bag for use by users. The ash powder produced after bag dust removal is transported to the ash bin through the ash conveying system for recovery and humidification and mixing for external transportation. The composition of the dust removal ash powder is complex, some components have high hardness, and have certain moisture absorption, adhesion and corrosiveness. The valves used in the current ash conveying system are usually pneumatic hard-sealed ceramic hemispherical valves, whose closing part is a sphere, which is a valve that is opened and closed by rotating the sphere around the center line of the valve body. The driving medium of the hemispherical valve is nitrogen, and the driving pressure is 500kpa.

[0003] In order to ensure the air tightness of the ceramic hard-sealed hemispherical valve, the valve core and the valve core are in hard-to-hard sealing contact, and there are no buffers or compensation parts between the valve components, so effective compensation cannot be made during operation; when there is dust accumulation or foreign matter adhering to the ceramic contact surface of the valve, the valve becomes stuck and cannot complete the self-cleaning function when the valve is switched, resulting in valve leakage; at the same time, eccentric ceramic hard-sealed hemispherical valves are mostly used for alumina powder, coal powder, coal ash, dusty gas, waste slag, etc., but the ceramic hemispherical valve does not take into account the ash content and characteristics in the dusty gas. Taking the dry dust removal ash of blast furnace gas in an iron and steel plant as an example, during the application process, the ash generated in the blast furnace gas has moisture absorption and adhesion, resulting in the formation of convex points or convex surfaces on the contact surface of the valve core. Due to the lack of compensation device, the valve core cracks during use, and eventually the valve body is perforated and leaks.

[0004] In view of the above problems, it is urgent to carry out innovative design based on the original ceramic hemispherical valve structure. Summary of the invention

[0005] The purpose of the present invention is to provide a method for explosion-proofing the ceramic valve core of a pneumatic hard-sealed ceramic hemispherical valve, so as to solve the problem that the ceramic hard-sealed hemispherical valve proposed in the above background technology is a ceramic hard-to-hard contact seal to ensure the airtight sealing of the valve, and there is no buffer or compensation part between the valve components, and effective compensation cannot be made during operation; when there is dust accumulation or foreign matter adhering to the ceramic contact surface of the valve, the valve becomes stuck, and the self-cleaning function cannot be completed when the valve is switched, resulting in valve leakage, and the eccentric ceramic hard-sealed hemispherical valve is mostly used for alumina powder, coal powder, coal ash, dusty gas, waste slag, etc., but the ceramic hemispherical valve does not take into account the ash content and characteristics in the dusty gas. During the application process, the ash generated in the blast furnace gas has moisture absorption and adhesion, resulting in the formation of convex points or convex surfaces on the contact surface of the valve core, and because there is no compensation device, the valve core cracks during use, which eventually leads to the problem of perforation and leakage of the valve body.

[0006] To achieve the above object, the present invention provides the following technical solution: a method for preventing the ceramic valve core of a pneumatic hard-sealed ceramic hemispherical valve from exploding, comprising the following steps:

[0007] S1: Disc spring selection and analysis stage:

[0008] S11: Based on the minimum preload specific pressure required by the disc spring, and the dimensions of the ball, ceramic valve body, and ceramic base, first try to take a group of disc springs, measure the dimensions of the disc springs, and record the dimensional data of the disc springs;

[0009] S12: According to GB / T 1972 standard, the force value that disc spring can provide is calculated, and the theoretical basis equation of GB / T 1972-2005 standard is adopted, as follows:

[0010]

[0011]

[0012]

[0013]

[0014] Among them: E--elastic modulus, 200GPa; ν--Poisson's ratio, 0.31; p--load, unit is N; h--free height, 3.7mm; r1--inner radius, unit is mm; r2--outer radius, unit is mm; δ--compression displacement, unit is mm;

[0015] S13: Substituting the size data of the disc spring into the above formula for calculation, and taking different δ values ​​corresponding to different loads p, thereby obtaining the load-displacement characteristic curve of the disc spring;

[0016] S14: The load-displacement characteristic curve of the disc spring is analyzed, and the relationship between the load and displacement of the disc spring is summarized based on the curve. The specific conclusions are as follows: when the compression displacement of the disc spring is 3.1mm, the force value provided is about 6500N, and as the compression displacement increases, the force value tends to be flat;

[0017] S2: Disc spring preparation stage:

[0018] S21: Calculate the most suitable size data of the disc spring according to the conclusion of the relationship between the load and displacement of the disc spring;

[0019] S22: Calculation of single disc springs: The same formula is used for disc springs with and without bearing surfaces. In order to make the calculated load of the disc spring with bearing surface (f = 0.75h0) equal to the calculated load of the disc spring with the same dimensions (D, d, H0) without bearing surface, the thickness of the disc spring with bearing surface should be reduced.

[0020] S23: The calculation formulas for the disc spring parameters are as follows:

[0021] Disc spring load: Spring stress:

[0022]

[0023]

[0024]

[0025]

[0026]

[0027] Where: F--disc spring load (N); Fc--disc spring flattening load (N); σ om --Stress at the disc spring OM point (MPa); σ t , σ n , σ m ,σ--Stress at Ⅰ, Ⅱ, Ⅲ, Ⅳ of disc spring (MPa); E--Elastic modulus (MPa); For elastic steel, E=2.06*10 5 MPa; μ--Poisson's ratio; C--ratio of outer diameter to inner diameter, C=D / d; K1, K1, K1, K1--calculation coefficient, calculated according to the following formula:

[0028]

[0029]

[0030]

[0031]

[0032] in:

[0033]

[0034]

[0035] S24: According to the calculation results of the above formula, the most suitable disc spring size data is obtained, and the disc spring is manufactured according to the data for standby;

[0036] S3: Disc spring assembly stage:

[0037] S31: Without damaging the ceramic hemispherical valve, disassemble the ceramic valve seat, ceramic valve core, valve seat gasket and other parts, and install the disc spring into the appropriate position in the hemispherical valve. After installation, install all parts back into the ceramic hemispherical valve as they are.

[0038] S4: Disc spring commissioning phase:

[0039] S41: Install the ceramic hemispherical valve equipped with disc spring back to the ash conveying system and start smelting in the blast furnace. The ash powder generated by the rough dust removal and fine dust removal of the blast furnace gas will pass through the ceramic hemispherical valve in turn. The air tightness of the hemispherical valve is tested to ensure that its air tightness is not affected by the disc spring.

[0040] S42: Continuously open and close the ceramic hemispherical valve to debug the disc spring and test whether the disc spring can effectively compensate when the valve assembly moves;

[0041] S43: Check whether the valve can complete self-cleaning when it is switched on and off, whether dust or foreign matter will accumulate on the valve ceramic contact surface during the dust conveying process, and whether the valve will become stuck;

[0042] S5: Production and use stage:

[0043] S51: After debugging and testing, disc springs are mass-produced according to the models and specifications of ceramic hemispheric valves. Disc springs of corresponding sizes for ceramic hemispheric valves of different models and specifications are prepared, and the produced disc springs are officially put into use. A disc spring of appropriate size is installed in each ceramic hemispheric valve.

[0044] Preferably, the elastic modulus in S12 is the stress of the disc spring under unidirectional stress state divided by the strain in that direction.

[0045] Preferably, the Poisson's ratio in S12 is the ratio of the absolute value of the lateral normal strain to the axial normal strain when the disc spring is subjected to unidirectional tension or compression, also called the lateral deformation coefficient, which is an elastic constant reflecting the lateral deformation of the disc spring.

[0046] Preferably, the disc spring load formula in S23 is, when the disc spring is flat, f=h0, and the disc spring load formula is simplified to:

[0047]

[0048] Compared with the prior art, the present invention provides an explosion-proof method for a ceramic valve core of a pneumatic hard-sealed ceramic hemispherical valve, which has the following advantages:

[0049] The disc springs of suitable sizes for different types of ceramic hemispherical valves are calculated through formulas, and the disc springs are installed between the valve components, so that there are disc springs between the valve components as compensation parts, which can avoid hard-to-hard sealing contact between the valve cores, and can effectively make compensation when the valve components are actuated. In addition, the grinding and self-cleaning function of the ceramic sealing surface of the ceramic valve during the switching process is improved. The ash powder in the blast furnace gas is not easy to form convex points or convex surfaces on the contact surface of the valve core, thereby solving the problem of valve jamming caused by foreign matter adhering to the valve core surface, and thus avoiding the problem of ceramic valve core bursting caused by repeated use of the jammed valve, which solves the valve leakage caused by valve sealing problems from the root and extends the service life of the valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a schematic diagram of the front cross-sectional structure of the present invention;

[0051] Figure 2 This is a schematic diagram of the three-dimensional structure of the ceramic valve core of the present invention;

[0052] Figure 3 This is a diagram showing the structure and size of the disc spring 3 of the present invention;

[0053] Figure 4 It is a load-displacement characteristic curve diagram of the disc spring 3 of the present invention.

[0054] In the figure: 1. Ceramic valve seat; 2. Ceramic valve core; 3. Disc spring; 4. Valve seat gasket. DETAILED DESCRIPTION

[0055] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0056] See also Figure 1-2 The present invention provides a technical solution: a method for preventing the ceramic valve core of a pneumatic hard-sealed ceramic hemispherical valve from exploding, comprising the following steps:

[0057] S1: Disc spring 3 selection analysis stage:

[0058] S11: According to the minimum preload specific pressure required by the disc spring 3, and the dimensions of the ball, the ceramic valve body, and the ceramic base, firstly, a group of disc springs 3 are tried, the dimensions of the disc springs 3 are measured, and the dimension data of the disc springs 3 are recorded. The structure and dimension data of the disc springs 3 are shown in the figure below;

[0059] S12: According to GB / T 1972 standard, calculate the force value that disc spring 3 can provide, using the theoretical basis equation of GB / T 1972-2005 standard, as follows:

[0060]

[0061]

[0062]

[0063]

[0064] Among them: E--elastic modulus, 200GPa; ν--Poisson's ratio, 0.31; p--load, unit is N; h--free height, 3.7mm; r1--inner radius, unit is mm; r2--outer radius, unit is mm; δ--compression displacement, unit is mm;

[0065] S13: Substitute the dimension data of the disc spring 3 into the above formula for calculation, and take different δ values ​​corresponding to different loads p, thereby obtaining the load-displacement characteristic curve of the disc spring 3, such as Figure 4 As shown;

[0066] S14: Analyze the load-displacement characteristic curve of the disc spring 3, and summarize the relationship between the load and displacement of the disc spring 3 based on the curve. The specific conclusions are as follows: when the compression displacement of the disc spring 3 is 3.1 mm, the force value provided is about 6500 N, and as the compression displacement increases, the force value tends to be flat;

[0067] S2: Disc spring 3 preparation stage:

[0068] S21: Calculating the most suitable size data of the disc spring 3 according to the conclusion of the relationship between the load and displacement of the disc spring 3;

[0069] S22: Calculation of single disc spring 3: The disc spring 3 without bearing surface and with bearing surface are calculated using the same formula. In order to make the calculated load of the disc spring 3 with bearing surface (f=0.75h0) equal to the calculated load of the disc spring 3 without bearing surface of the same size (D, d, H0), the thickness of the disc spring 3 with bearing surface should be thinned;

[0070] S23: The calculation formulas for the parameters of disc spring 3 are as follows:

[0071] Disc spring 3 load: Spring stress:

[0072]

[0073]

[0074]

[0075]

[0076]

[0077] Where: F--disc spring 3 load (N); Fc--disc spring 3 flattening load (N); σ om --Stress at 3OM point of disc spring (MPa); σ t , σ n , σ m ,σ--Stress at 3Ⅰ, Ⅱ, Ⅲ, Ⅳ of disc spring (MPa); E--Elastic modulus (MPa); For elastic steel, E=2.06*10 5 MPa; μ--Poisson's ratio; C--ratio of outer diameter to inner diameter, C=D / d; K1, K1, K1, K1--calculation coefficient, calculated according to the following formula:

[0078]

[0079]

[0080]

[0081]

[0082] in:

[0083]

[0084]

[0085] S24: according to the calculation result of the above formula, the most suitable size data of the disc spring 3 is obtained, and the disc spring 3 is manufactured according to the data for standby;

[0086] S3: Disc spring 3 assembly stage:

[0087] S31: Without damaging the ceramic hemispherical valve, disassemble the ceramic valve seat 1, ceramic valve core 2, valve seat gasket 4 and other parts, and install the disc spring 3 into the appropriate position in the hemispherical valve. After installation, install the parts back into the ceramic hemispherical valve as they are. After assembly, the positions of the parts are as shown below. Figure 1 As shown;

[0088] S4: Disc spring 3 commissioning stage:

[0089] S41: The ceramic hemispherical valve equipped with the disc spring 3 is installed back into the ash conveying system, and the blast furnace is started for smelting. The ash powder generated after the blast furnace gas undergoes rough dust removal and fine dust removal will pass through the ceramic hemispherical valve in sequence. The air tightness of the hemispherical valve is tested to ensure that the air tightness is not affected by the disc spring 3.

[0090] S42: continuously opening and closing the ceramic hemispherical valve, debugging the disc spring 3, and detecting whether the disc spring 3 can effectively compensate when the valve assembly is actuated;

[0091] S43: Check whether the valve can complete self-cleaning when it is switched on and off, whether dust or foreign matter will accumulate on the valve ceramic contact surface during the dust conveying process, and whether the valve will become stuck;

[0092] S5: Production and use stage:

[0093] S51: After debugging and testing, disc springs 3 are mass-produced according to the model and specifications of the ceramic hemispheric valve, disc springs 3 of sizes corresponding to the different models and specifications of ceramic hemispheric valves are prepared, and the produced disc springs 3 are officially put into use, and a disc spring 3 of suitable size is installed in each ceramic hemispheric valve.

[0094] The elastic modulus in S12 is the stress of disc spring 3 in the unidirectional stress state divided by the strain in that direction;

[0095] The Poisson's ratio in S12 is the ratio of the absolute value of the lateral normal strain to the axial normal strain when the disc spring 3 is subjected to unidirectional tension or compression, also called the lateral deformation coefficient, which is an elastic constant reflecting the lateral deformation of the disc spring 3;

[0096] The load formula of disc spring 3 in S23 is that when disc spring 3 is flat, f=h0, and the load formula of disc spring 3 is simplified to:

[0097]

[0098] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

[0099] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preventing the ceramic valve core of a pneumatic hard-sealed ceramic hemispherical valve from exploding, comprising the following steps, characterized in that: S1: Disc spring selection and analysis stage: S11: Based on the minimum preload specific pressure required by the disc spring, and the dimensions of the ball, ceramic valve body, and ceramic base, first try to take a group of disc springs, measure the dimensions of the disc springs, and record the dimensional data of the disc springs; S12: According to GB / T 1972 standard, the force value that disc spring can provide is calculated, and the theoretical basis equation of GB / T 1972-2005 standard is adopted, as follows: Where: E is the elastic modulus, which is 200GPa; ν is the Poisson's ratio; p is the load, in N; h is the free height; r1 is the inner radius, in mm; r2 is the outer radius, in mm; δ is the compression displacement, in mm; S13: Substituting the size data of the disc spring into the above formula for calculation, and taking different δ values ​​corresponding to different loads p, thereby obtaining the load-displacement characteristic curve of the disc spring; S14: The load-displacement characteristic curve of the disc spring is analyzed, and the relationship between the load and displacement of the disc spring is summarized based on the curve. The specific conclusions are as follows: when the compression displacement of the disc spring is 3.1mm, the force value provided is 6500N, and as the compression displacement increases, the force value tends to be flat; S2: Disc spring preparation stage: S21: Calculate the most suitable size data of the disc spring according to the conclusion of the relationship between the load and displacement of the disc spring; S22: Calculation of single disc springs: The same formula is used for disc springs with and without bearing surfaces. In order to make the calculated load f=0.75h0 of the disc spring with bearing surface equal to the calculated load of the disc spring with the same dimensions (D, d, H0) without bearing surface, the thickness of the disc spring with bearing surface should be reduced. S23: The calculation formulas for the disc spring parameters are as follows: Disc spring load: Spring stress: Where: F--disc spring load; F C --Load when disc spring is flattened; σ OM --Stress at the disc spring OM point; σ I , σ II , σ III , σ IV --Stress at points Ⅰ, Ⅱ, Ⅲ, and Ⅳ of disc spring; E--elastic modulus; for elastic steel, E=2.06×10 5 MPa; μ--Poisson's ratio; C--ratio of outer diameter to inner diameter, C=D / d; K1, K2, K3, K4--calculation coefficients, calculated according to the following formula: in: S24: according to the calculation result of the above formula, the most suitable disc spring size data is obtained, and the disc spring is manufactured according to the size data for standby; S3: Disc spring assembly stage: S31: Without damaging the ceramic hemispherical valve, disassemble the ceramic valve seat, ceramic valve core, and valve seat gasket parts, and install the disc spring into the appropriate position in the hemispherical valve. After installation, install all parts back into the ceramic hemispherical valve as they were. S4: Disc spring commissioning phase: S41: Install the ceramic hemispherical valve equipped with disc spring back to the ash conveying system and start smelting in the blast furnace. The ash powder generated by the rough dust removal and fine dust removal of the blast furnace gas will pass through the ceramic hemispherical valve in turn. The air tightness of the hemispherical valve is tested to ensure that its air tightness is not affected by the disc spring. S42: Continuously open and close the ceramic hemispherical valve to debug the disc spring and test whether the disc spring can effectively compensate when the valve assembly moves; S43: Check whether the valve can complete self-cleaning when it is switched on and off, whether dust or foreign matter will accumulate on the valve ceramic contact surface during the dust conveying process, and whether the valve will become stuck; S5: Production and use stage: S51: After debugging and testing, disc springs are mass-produced according to the models and specifications of ceramic hemispheric valves. Disc springs of corresponding sizes for ceramic hemispheric valves of different models and specifications are prepared, and the produced disc springs are officially put into use. A disc spring of appropriate size is installed in each ceramic hemispheric valve.

2. The method for preventing the ceramic valve core of a pneumatic hard-sealed ceramic hemispherical valve according to claim 1 is characterized in that: The Poisson's ratio in S12 is the ratio of the absolute value of the lateral normal strain to the axial normal strain when the disc spring is subjected to unidirectional tension or compression, also called the lateral deformation coefficient, which is an elastic constant reflecting the lateral deformation of the disc spring.

3. The explosion-proof method for a ceramic valve core of a pneumatic hard-sealed ceramic hemispherical valve according to claim 1 is characterized in that: The disc spring load formula in S23 is that when the disc spring is flat, f=h0, and the disc spring load formula is simplified to:

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