This paper analyses the principle of microwave humidity testing. According to the problems in the production procedure of ceramic products, a microwave humidity testing system is designed and analyzed for its advantag...This paper analyses the principle of microwave humidity testing. According to the problems in the production procedure of ceramic products, a microwave humidity testing system is designed and analyzed for its advantages. Furthermore, the system has been applied to the production line that produces ceramic products and the testing results are also satisfying.展开更多
The prevention and control of natural gas hydrate(hereinafter,“hydrate”for short)blockage during deepwater gas well production tests is very important in ensuring the test safety.In this paper,the distribution of we...The prevention and control of natural gas hydrate(hereinafter,“hydrate”for short)blockage during deepwater gas well production tests is very important in ensuring the test safety.In this paper,the distribution of wellbore temperature and pressure field under different test conditions was analyzed,and the changes of hydrate deposition and blockage degree in the pipe string in the whole process of test under different test systems were evaluated using the hydrate generationedepositionedecomposition calculation method.On this basis,a deepwater gas well production test method based on hydrate prevention and control was proposed.And the following research results were obtained.First,in the process of deepwater gas well tests,the vaporeliquid phase of annular-mist flow pattern with the greatest risk of hydrate blockage is often formed in the wellbore.Therefore,it is more reasonable to take measures to prevent hydrate blockage in the process of tests than to prevent the formation of hydrate.Second,when the conventional four-point test method is used,it is required to set low gas production measurement points with lower flowing temperature.In the wellbore with high temperature and low temperature,however,hydrate tends to form and deposit easily,and a long period of test will increase the risk of test string blockage.Third,the mixed-sequence test system suitable for deepwater gas well tests can change wellbore temperature by adjusting the sequence of measuring points without changing the production rate and duration,so as to decompose hydrate sediment layers and reduce the maximum blockage degree of test string in the process of tests.Fourth,a three-point or two-point test method is recommended for deepwater gas wells without sand production,stress sensitivity,retrograde condensation and water production.Superior to the conventional four-point test method,three-point and two-point test methods can effectively reduce the risk of hydrate deposition and blockage in the test string,and it can shorten the testing time and reduce the test cost on the premise of ensuring the accuracy of the productivity equation.In conclusion,the research results are of help to the field test construction of deepwater gas wells.展开更多
This standard specifies the definitions, theory, apparatus, specimens, procedures, test results and disposal, test error and report of test method for refractoriness under load of refractory products （non-differentia...This standard specifies the definitions, theory, apparatus, specimens, procedures, test results and disposal, test error and report of test method for refractoriness under load of refractory products （non-differential, with rising temperature）.展开更多
In this paper, the mechanical properties of gas hydrate-bearing sediments (GHBS) were summarized and the instability mechanism of submarine hydrate-bearing slope (SHBS) was analyzed under the background of the test pr...In this paper, the mechanical properties of gas hydrate-bearing sediments (GHBS) were summarized and the instability mechanism of submarine hydrate-bearing slope (SHBS) was analyzed under the background of the test production of gas hydrate in the northern part of the South China Sea. The strength reduction finite element method (SRFEM) was introduced to the stability analysis of submarine slopes for the safety of the test production. Two schemes were designed to determine the physical and mechanical parameters of four target wells. Through the division of the hydrate dissociation region and the design of four working conditions, the range and degree of hydrate dissociation at different stages during the test production were simulated. Based on the software ABAQUS, 37 FEM models of SHBS were set up to analyze and assess the stability of the submarine slopes in the area of the test production. Necessary information such as safety factors, deformation, and displacement were obtained at different stages and under different working conditions. According to the calculation results, the submarine slope area is stable before the test production, and the safety factors almost remains the same during and after the test production. All these indicate that the test production has no obvious influence on the area of the test production and the submarine slopes in the area are stable during and after the test production.展开更多
This standard specifies the method summary, reagents, apparatus, sampling, procedure, test results calculation and permissible tolerance of the determination of magnesium oxide by CyDTA volumetric method.
ISO releases two standards for textiles.Recently,two international standards,ISO 8159:2025,Textiles-Morphology of fibres and yarns-Vocabulary,and ISO 17971:2025,Textiles-Smart textiles-Test method for determining the ...ISO releases two standards for textiles.Recently,two international standards,ISO 8159:2025,Textiles-Morphology of fibres and yarns-Vocabulary,and ISO 17971:2025,Textiles-Smart textiles-Test method for determining the screen-touch properties of fabrics,were officially released.They are of positive significance for eliminating technical ambiguities in exchanges on textile products and filling the gaps in international standards.展开更多
Based on the study of the relation between the dynamic imbalance degree and the product of inertia,a new static test method of the dynamic imbalance degree is presented.It is theoretically proved that the essence of t...Based on the study of the relation between the dynamic imbalance degree and the product of inertia,a new static test method of the dynamic imbalance degree is presented.It is theoretically proved that the essence of the imbalance degree test for projectile body is the test of its product of inertia.A more precise calculation formula of dynamic imbalance degree is also given.The experiment results show that this method can not only reduce the cost of equipment,simplify the test procedures,save human resource,but also has more reliable test precision.展开更多
文摘This paper analyses the principle of microwave humidity testing. According to the problems in the production procedure of ceramic products, a microwave humidity testing system is designed and analyzed for its advantages. Furthermore, the system has been applied to the production line that produces ceramic products and the testing results are also satisfying.
基金supported by the National Program on Key Basic Research Project(973 Program)“Deep-water oil and gas well completion and production tests optimization”(No.:2015CB251205).
文摘The prevention and control of natural gas hydrate(hereinafter,“hydrate”for short)blockage during deepwater gas well production tests is very important in ensuring the test safety.In this paper,the distribution of wellbore temperature and pressure field under different test conditions was analyzed,and the changes of hydrate deposition and blockage degree in the pipe string in the whole process of test under different test systems were evaluated using the hydrate generationedepositionedecomposition calculation method.On this basis,a deepwater gas well production test method based on hydrate prevention and control was proposed.And the following research results were obtained.First,in the process of deepwater gas well tests,the vaporeliquid phase of annular-mist flow pattern with the greatest risk of hydrate blockage is often formed in the wellbore.Therefore,it is more reasonable to take measures to prevent hydrate blockage in the process of tests than to prevent the formation of hydrate.Second,when the conventional four-point test method is used,it is required to set low gas production measurement points with lower flowing temperature.In the wellbore with high temperature and low temperature,however,hydrate tends to form and deposit easily,and a long period of test will increase the risk of test string blockage.Third,the mixed-sequence test system suitable for deepwater gas well tests can change wellbore temperature by adjusting the sequence of measuring points without changing the production rate and duration,so as to decompose hydrate sediment layers and reduce the maximum blockage degree of test string in the process of tests.Fourth,a three-point or two-point test method is recommended for deepwater gas wells without sand production,stress sensitivity,retrograde condensation and water production.Superior to the conventional four-point test method,three-point and two-point test methods can effectively reduce the risk of hydrate deposition and blockage in the test string,and it can shorten the testing time and reduce the test cost on the premise of ensuring the accuracy of the productivity equation.In conclusion,the research results are of help to the field test construction of deepwater gas wells.
文摘This standard specifies the definitions, theory, apparatus, specimens, procedures, test results and disposal, test error and report of test method for refractoriness under load of refractory products （non-differential, with rising temperature）.
基金This work is funded by National Key R&D Project (2017YFC0307605)the China Geological Survey (DD20160217,DD20190218)+1 种基金the National Natural Science Foundation of China (11572165)we would like to extend our sincere appreciation for these.
文摘In this paper, the mechanical properties of gas hydrate-bearing sediments (GHBS) were summarized and the instability mechanism of submarine hydrate-bearing slope (SHBS) was analyzed under the background of the test production of gas hydrate in the northern part of the South China Sea. The strength reduction finite element method (SRFEM) was introduced to the stability analysis of submarine slopes for the safety of the test production. Two schemes were designed to determine the physical and mechanical parameters of four target wells. Through the division of the hydrate dissociation region and the design of four working conditions, the range and degree of hydrate dissociation at different stages during the test production were simulated. Based on the software ABAQUS, 37 FEM models of SHBS were set up to analyze and assess the stability of the submarine slopes in the area of the test production. Necessary information such as safety factors, deformation, and displacement were obtained at different stages and under different working conditions. According to the calculation results, the submarine slope area is stable before the test production, and the safety factors almost remains the same during and after the test production. All these indicate that the test production has no obvious influence on the area of the test production and the submarine slopes in the area are stable during and after the test production.
文摘This standard specifies the method summary, reagents, apparatus, sampling, procedure, test results calculation and permissible tolerance of the determination of magnesium oxide by CyDTA volumetric method.
文摘ISO releases two standards for textiles.Recently,two international standards,ISO 8159:2025,Textiles-Morphology of fibres and yarns-Vocabulary,and ISO 17971:2025,Textiles-Smart textiles-Test method for determining the screen-touch properties of fabrics,were officially released.They are of positive significance for eliminating technical ambiguities in exchanges on textile products and filling the gaps in international standards.
文摘Based on the study of the relation between the dynamic imbalance degree and the product of inertia,a new static test method of the dynamic imbalance degree is presented.It is theoretically proved that the essence of the imbalance degree test for projectile body is the test of its product of inertia.A more precise calculation formula of dynamic imbalance degree is also given.The experiment results show that this method can not only reduce the cost of equipment,simplify the test procedures,save human resource,but also has more reliable test precision.
