CN115436188A - Device and method for testing influence of actual working conditions of power station boiler on mechanical properties of materials - Google Patents

Device and method for testing influence of actual working conditions of power station boiler on mechanical properties of materials Download PDF

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Publication number
CN115436188A
CN115436188A CN202210919060.8A CN202210919060A CN115436188A CN 115436188 A CN115436188 A CN 115436188A CN 202210919060 A CN202210919060 A CN 202210919060A CN 115436188 A CN115436188 A CN 115436188A
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testing
test
influence
temperature
mechanical properties
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张广兴
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Guoneng Boiler And Pressure Vessel Inspection Co ltd
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Guoneng Boiler And Pressure Vessel Inspection Co ltd
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/08—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
    • G01N3/18—Performing tests at high or low temperatures
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D21/00—Measuring or testing not otherwise provided for
    • G01D21/02—Measuring two or more variables by means not covered by a single other subclass
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/02—Details
    • G01N3/06—Special adaptations of indicating or recording means
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/02—Details not specific for a particular testing method
    • G01N2203/0202—Control of the test
    • G01N2203/0208—Specific programs of loading, e.g. incremental loading or pre-loading

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  • General Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)

Abstract

The invention provides a test device and a method for the influence of the actual working condition of a power station boiler on the mechanical property of a material, wherein the method is suitable for the mechanical property test of all metal parts of the power station boiler and is also suitable for other parts of a power station bearing high temperature and high pressure; the method has the advantages that the actual operation parameters are collected, the degree of coincidence with the actual working conditions is high, and the practicability is high; the testing device is additionally provided with a computer control system on the basis of the original creep machine, and the testing can be completed by device transformation, so that the cost is saved; the influence of the current generator set depth peak regulation on the equipment can be roughly determined by the test method; the designed chuck is used for hanging a plurality of samples through one testing machine, so that the temperatures of the samples are the same, the tension can be controlled independently and simultaneously, the testing errors caused by different factors of the testing machine are reduced, and the accuracy and comparability of the obtained testing results are greatly improved.

Description

Device and method for testing influence of actual working conditions of power station boiler on mechanical properties of materials
Technical Field
The invention relates to a device and a method for testing influence of actual working conditions of a power station boiler on mechanical properties of materials.
Background
The main body part of the utility boiler mainly comprises various metal materials, in particular to high-temperature and high-pressure parts. The low-temperature part of the subcritical boiler mainly uses low alloy steel such as manganese steel, low carbon steel, 15CrMo, 12Cr1MoV and the like, and the high-temperature part in the boiler mainly uses high alloy steel such as 91, TP347 and the like. With the use of a large number of domestic ultra (supercritical) high-capacity and high-parameter units, high-grade metal materials such as TP347HFG, super304, HR3C and the like are widely applied.
In order to reduce the coal consumption of the utility boiler, the most direct and effective method is to use a high-parameter unit, and high-temperature resistant metal materials are required. How to ensure the long-term safe and stable operation of the metal material of the power station boiler is a very important subject, the mechanical property of the material is a direct influence factor, and the temperature and the pressure are the most important parameters of the mechanical property.
The conventional research on the mechanical properties of materials mainly depends on a mechanical property testing machine, a creep machine and the like, and is used for detecting the normal-temperature mechanical properties, the high-temperature mechanical properties, the long-term mechanical properties and the like of the metal materials. When the power station boiler operates, two important parameters of temperature and pressure born by a metal material are not constant but fluctuate, particularly, the temperature and pressure of a unit are changed greatly along with the influence of peak shaving and deep peak shaving of the unit, and all values obtained by using a conventional mechanical property test have larger deviation from the actual values.
Therefore, it is necessary to invent a test device and a method for the influence of the actual working conditions of the utility boiler on the mechanical properties of the material, so as to test the mechanical property data of the material of the utility boiler during the variable-parameter operation, and guide the selection and the replacement of the material of the utility boiler.
Disclosure of Invention
The technical problem that this patent will be solved provides a power plant boiler actual condition to test device and method of material mechanical properties influence. The method is based on a creep testing machine, aiming at a selected testing component, actual operation working condition parameters (mainly acquired data are temperature and pressure) are acquired, the data are used as experimental parameters, the temperature and the tensile force of the creep testing machine are accurately controlled by a computer, variable parameter creep performance testing is carried out, testing results are compared with conventional creep testing parameters through testing in multiple time periods, yield strength ratio and tensile strength ratio are obtained, a comparison curve is established, the influence degree of variable parameter operation of the component is evaluated, and the use and the replacement of materials are guided.
In order to solve the technical problems, the test device for the influence of the actual working condition of the power station boiler on the mechanical property of the material comprises a test machine, wherein the test machine comprises a female chuck and a plurality of sub chucks, the sub chucks can be controlled independently, the computer control adopts a multi-channel technology, each channel can control one sub chuck independently, each test device can be used for hanging a plurality of samples for testing, and the influence of the difference among different test machines on the result is reduced;
the testing system has the functions of reading MIS temperature and pressure parameters, comparing the pressure parameters with design pressure to calculate test tension, controlling temperature by variable parameters, controlling tension by variable parameters and the like.
The method for testing the influence of the actual working condition of the power station boiler on the mechanical property of the material comprises the following steps:
s1, selecting a specific unit according to needs, such as a unit which participates in peak shaving for a long time, has large running load fluctuation and many non-stop conditions and is difficult to find reasons, and selecting specific components, such as easily-leaked components, seriously-aged components, blown-damaged components and the like, to perform tests;
s2, selecting a sample and a spare part participating in operation, and processing the sample according to standard requirements; according to the actual operation condition and the test time length;
s3, the test temperature of the spare parts is the design temperature, and the test tension a is the lasting strength of the material at the design temperature;
s4, test parameters of the running sample: directly reading the temperature parameters in the MIS system by a computer, and controlling the test temperature by a temperature sensor;
s5, the test parameters can be selected according to the test time nodes, and also can be selected in individual time intervals for cyclic adjustment;
s6, after the test is finished, performing a high-temperature tensile test on the samples, wherein the temperature is selected as a design temperature, and obtaining the yield strength and the tensile strength of each sample;
s7, comparing the running sample result at each time point with the spare part sample result, calculating a yield strength ratio and a tensile strength ratio, and establishing a comparison curve;
s8, taking the yield strength ratio and the tensile strength ratio as influence factors of variable working condition operation on the mechanical property of the metal material;
and S9, selecting test data with reference value, discarding the data with large dispersion ratio, and taking the arithmetic mean value of the rest data of the same time node.
Preferably, in the step S1, a representative operation time period in the MIS system is selected, and the downloading of the temperature and pressure parameters is called.
Preferably, 5 samples are processed at each time node in the step S2; the time points are selected from 720h and 2160h respectively, which correspond to 1 month and 3 months respectively.
Preferably, the pressure parameter in the step S4 is compared with the design pressure to obtain a contrast coefficient μ, and the test tension a1 is: a1= μ a.
Compared with the related technology, the test device and the method for the influence of the actual working condition of the power station boiler on the mechanical property of the material have the following beneficial effects:
the invention provides a test device and a method for the influence of the actual working condition of a power station boiler on the mechanical property of a material, wherein the method is suitable for the mechanical property test of all metal parts of the power station boiler and is also suitable for other parts of a power station bearing high temperature and high pressure; the method has the advantages that the actual operation parameters are collected, the coincidence degree with the actual working conditions is high, and the practicability is high; the testing device is additionally provided with a computer control system on the basis of the original creep machine, and can be completed through device transformation, so that the cost is saved; the influence of the depth peak regulation of the current generator set on the equipment can be roughly determined by the test method; the designed chuck is used for hanging a plurality of samples through one testing machine, so that the temperatures of the samples are the same, the tension can be controlled independently and simultaneously, the testing errors caused by different factors of the testing machine are reduced, and the accuracy and comparability of the obtained testing results are greatly improved.
Drawings
FIG. 1 is a schematic method flow diagram of a preferred embodiment of the test device and method for the influence of the actual working conditions of the utility boiler on the mechanical properties of the material provided by the invention.
Detailed Description
The invention is further described below with reference to the drawings and the embodiments.
Please refer to fig. 1, wherein fig. 1 is a schematic method flow diagram of a test apparatus and a method for testing influence of actual working conditions of a utility boiler on mechanical properties of materials according to a preferred embodiment of the present invention.
Example one
The testing device comprises a testing machine, wherein the testing machine comprises a female chuck and a plurality of sub chucks, the sub chucks can be controlled independently, the computer control adopts a multi-channel technology, and each channel can control one sub chuck independently. Each testing device can be used for hanging a plurality of samples for testing, so that the influence of the difference between different testing machines on the result is reduced;
the testing system has the functions of reading MIS temperature and pressure parameters, comparing the pressure parameters with the designed pressure to calculate the test tension, controlling the temperature in variable parameters, controlling the tension in variable parameters, etc. the method needs no additional hardware cost and only needs to design one small control software.
The method of the test device for the influence of the actual working condition of the utility boiler on the mechanical property of the material comprises the following steps:
1. selecting a specific unit according to the requirement, such as a unit which participates in peak regulation for a long time, has large operation load fluctuation, has multiple non-stop conditions and is difficult to find reasons, and selecting specific components, such as easily leaked components, seriously aged components, blown components and the like for testing; selecting a representative operation time period in the MIS system, and calling temperature and pressure parameters for downloading;
2. selecting samples and spare parts participating in operation, and processing the samples according to standard requirements; processing 5 samples at each time node according to the actual operation condition and the test time length; selecting 720h and 2160h respectively for selecting time points, which respectively correspond to 1 month and 3 months;
3. the test temperature of the spare parts is the design temperature, and the test tension a is the lasting strength of the material at the design temperature;
4. test parameters of the run samples: directly reading the temperature parameters in the MIS system by a computer, and controlling the test temperature by a temperature sensor; the pressure parameter is compared with the design pressure to obtain a contrast coefficient mu, and the test tension a1 is as follows:
a1＝μa
5. the test parameters can be selected according to test time nodes, and can also be selected in individual time periods for cyclic adjustment;
6. after the test is finished, performing a high-temperature tensile test on the samples, wherein the temperature is selected as a design temperature, and obtaining the yield strength and the tensile strength of each sample;
7. comparing the operation sample result at each time point with the spare part sample result, calculating the yield strength ratio and the tensile strength ratio, and establishing a comparison curve;
8. taking the yield strength ratio and the tensile strength ratio as the influence factors of variable working condition operation on the mechanical property of the metal material;
9. the test data is selected to have reference value, the data with larger dispersion is abandoned, and the rest data of the same time node is subjected to arithmetic mean value.
Example two
The test device for the influence of the actual working condition of the power station boiler on the mechanical property of the material comprises a test machine, wherein the test machine comprises a female chuck and a plurality of sub chucks, the sub chucks can be controlled independently, a multi-channel technology is adopted for computer control, and each channel can control one sub chuck independently. Each test device can be used for hanging a plurality of samples for testing, so that the influence of the difference among different testing machines on the result is reduced;
the testing system has the functions of reading MIS temperature and pressure parameters, comparing the pressure parameters with the designed pressure to calculate the test tension, controlling the temperature in variable parameters, controlling the tension in variable parameters, etc. the method needs no additional hardware cost and only needs to design one small control software.
The method of the test device for the influence of the actual working condition of the utility boiler on the mechanical property of the material comprises the following steps:
1. selecting a specific unit according to the requirement, such as a unit which participates in peak regulation for a long time, has large operation load fluctuation, has multiple non-stop conditions and is difficult to find reasons, and selecting specific components, such as easily leaked components, seriously aged components, blown components and the like for testing; selecting a representative operation time period in the MIS system, and calling temperature and pressure parameters for downloading;
2. selecting samples and spare parts participating in operation, and processing the samples according to standard requirements; processing 5 samples at each time node according to the actual operation condition and the test time length; selecting 4320h and 8640h from time points respectively, wherein the time points correspond to half a year and a year respectively;
3. the test temperature of the spare parts is the design temperature, and the test tension a is the lasting strength of the material at the design temperature;
4. test parameters of the run samples: directly reading the temperature parameters in the MIS system by a computer, and controlling the test temperature by a temperature sensor; the pressure parameter is compared with the design pressure to obtain a contrast coefficient mu, and the test tension a1 is as follows:
a1＝μa
5. the test parameters can be selected according to test time nodes, and can also be selected in individual time periods for cyclic adjustment;
6. after the test is finished, performing a high-temperature tensile test on the samples, wherein the temperature is selected as a design temperature, and obtaining the yield strength and the tensile strength of each sample;
7. comparing the operation sample result at each time point with the spare part sample result, calculating the yield strength ratio and the tensile strength ratio, and establishing a comparison curve;
8. taking the yield strength ratio and the tensile strength ratio as the influence factors of variable working condition operation on the mechanical property of the metal material;
9. the test data is selected to have reference value, the data with larger dispersion is abandoned, and the rest data of the same time node is subjected to arithmetic mean value.
The working principle of the test device and the method for the influence of the actual working conditions of the power station boiler on the mechanical properties of the materials is as follows:
the method is suitable for testing the mechanical properties of all metal parts of the power station boiler and is also suitable for other parts of the power station which bear high temperature and high pressure;
the method has the advantages that the actual operation parameters are collected, the degree of coincidence with the actual working conditions is high, and the practicability is high;
the testing device is additionally provided with a computer control system on the basis of the original creep machine, and can be completed through device transformation, so that the cost is saved;
the influence of the current generator set depth peak regulation on the equipment can be roughly determined by the test method;
the designed chuck is used for hanging a plurality of samples through one testing machine, so that the temperatures of the samples are the same, the tension can be controlled independently or simultaneously, the testing errors caused by different factors of the testing machine are reduced, and the accuracy and comparability of the obtained testing result are greatly improved.
1. Selecting a machine set, selecting a specific component and selecting test time.
2. The test specimens were processed to the test standards.
3. The operation condition of the unit is collected, the temperature parameters are led into a computer of the testing device, the pressure parameters are compared with the conventional testing parameters, and the pressure parameters are converted into the tension parameters to be led into the computer of the testing device.
4. The processed sample was loaded into a test apparatus.
5. The test was started.
6. And after the creep test is finished, performing a high-temperature tensile test on all the samples to obtain the yield strength and the tensile strength of each sample.
7. And comparing the running sample result with the spare part sample result at each time point, calculating the yield strength ratio and the tensile strength ratio, and establishing a comparison curve.
8. And taking the yield strength ratio and the tensile strength ratio as the influence factors of variable working condition operation on the mechanical property of the metal material.
9. The test was completed.
Compared with the related technology, the test device and the method for the influence of the actual working condition of the power station boiler on the mechanical property of the material have the following beneficial effects:
the method is suitable for testing the mechanical properties of all metal parts of the power station boiler and is also suitable for other parts of the power station which bear high temperature and high pressure;
the method has the advantages that the actual operation parameters are collected, the degree of coincidence with the actual working conditions is high, and the practicability is high;
the testing device is additionally provided with a computer control system on the basis of the original creep machine, and can be completed through device transformation, so that the cost is saved;
the influence of the depth peak regulation of the current generator set on the equipment can be roughly determined by the test method;
the designed chuck is used for hanging a plurality of samples through one testing machine, so that the temperatures of the samples are the same, the tension can be controlled independently and simultaneously, the testing errors caused by different factors of the testing machine are reduced, and the accuracy and comparability of the obtained testing results are greatly improved.
The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims (10)

1. The utility model provides a test device of power plant boiler actual conditions to mechanical properties of material influence which characterized in that: the testing machine comprises a main chuck and a plurality of sub chucks, wherein the sub chucks can be controlled independently, the computer control adopts a multi-channel technology, each channel can control one sub chuck independently, each testing device can hang a plurality of samples for testing, and the influence of the difference among different testing machines on the result is reduced;
the testing system has the functions of reading MIS temperature and pressure parameters, comparing the pressure parameters with design pressure to calculate test tension, controlling temperature in variable parameters, controlling tension in variable parameters, etc.
2. The method for testing the influence of the actual working condition of the power station boiler on the mechanical property of the material is characterized by comprising the following steps of:
s1, selecting a specific unit according to needs, such as a unit which participates in peak shaving for a long time, has large fluctuation of running load, has many non-stop conditions and is difficult to find reasons, and the like;
s2, selecting a sample and a spare part which participate in operation, and processing the sample according to standard requirements;
s3, the test temperature of the spare parts is the design temperature, and the test tension a is the endurance strength of the material at the design temperature;
s4, test parameters of the running sample: directly reading the temperature parameters in the MIS system by a computer;
s5, calling the test parameters can be selected according to the test time nodes;
s6, after the test is finished, performing a high-temperature tensile test on the samples, wherein the temperature is selected as a design temperature, and obtaining the yield strength and the tensile strength of each sample;
s7, comparing the running sample result at each time point with the spare part sample result, calculating a yield strength ratio and a tensile strength ratio, and establishing a comparison curve;
s8, taking the yield strength ratio and the tensile strength ratio as influence factors of variable working condition operation on the mechanical property of the metal material;
and S9, selecting the test data with reference value, and discarding the data with large dispersion ratio.
3. The method for testing the influence of the practical working conditions of the utility boiler on the mechanical properties of the materials as claimed in claim 2, wherein the representative operation time period in the MIS system is selected in the step S1, and the temperature and pressure parameters are taken and downloaded.
4. The method for testing the influence of the actual working conditions of the utility boiler on the mechanical properties of the materials as claimed in claim 2, wherein 5 samples are processed at each time node in the step S2; the selection of time points is respectively 720h and 2160h, which respectively correspond to 1 month and 3 months.
5. The method for testing the influence of the actual working conditions of the utility boiler on the mechanical properties of the materials as claimed in claim 2, wherein the pressure parameter in the step S4 is compared with the design pressure to obtain a contrast coefficient μ, and the test tension a1 is as follows: a1= μ a.
6. The method for testing the influence of the actual working conditions of the utility boiler on the mechanical properties of the materials as claimed in claim 2, wherein in the step S1, specific parts, such as parts prone to leakage, parts with serious aging, parts damaged by blowing and the like, are selected for testing.
7. The method for testing the influence of the actual working conditions of the utility boiler on the mechanical properties of the materials as claimed in claim 2, wherein in the step S2, the test time is determined according to the actual operating conditions.
8. The method for testing the influence of the actual working conditions of the utility boiler on the mechanical properties of the materials as claimed in claim 2, wherein in the step S4, the test temperature is controlled by a temperature sensor.
9. The method for testing the influence of the actual working conditions of the utility boiler on the mechanical properties of the materials as claimed in claim 2, wherein in the step S5, the individual time intervals can be selected for cyclic adjustment.
10. The method for testing the influence of the actual working conditions of the utility boiler on the mechanical properties of the materials as claimed in claim 2, wherein in the step S9, the data of the remaining same time node is subjected to arithmetic mean.
CN202210919060.8A 2022-08-02 2022-08-02 Device and method for testing influence of actual working conditions of power station boiler on mechanical properties of materials Pending CN115436188A (en)

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CN202210919060.8A CN115436188A (en) 2022-08-02 2022-08-02 Device and method for testing influence of actual working conditions of power station boiler on mechanical properties of materials

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Application Number Priority Date Filing Date Title
CN202210919060.8A CN115436188A (en) 2022-08-02 2022-08-02 Device and method for testing influence of actual working conditions of power station boiler on mechanical properties of materials

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