38 results about "Failure assessment" patented technology

The present invention belongs to the field of an automatic monitoring technology for city gas network, which relates to a warning method for gas network accident. The present invention comprises steps as follows: a gas network geographic information system is established; a gas network diagram which is drawn is read; a gas network attributing data and a spatial geographical data are read; the maximum allowable working pressure and the residual life time for the pipeline, including fault, are predicted by adopting the methods based on an invalid evaluation drawing and an artificial neural network; the real-time collection and automatic monitoring system of the gas network data is established; dynamic data, including the pressure of all pipeline nodes are collected real-timely; a dynamic or static alarming mechanism which real-timely monitors whether the pipeline in service leaks, operating pressure and service life is established. The gas network accident warning method provided by the present invention can effectively prevent serious gas accidents.

A dynamic assessment system for monitoring high-voltage electrical components, which includes a computer system that is configured to receive data from a plurality of on-line sensors configured to monitor various operating parameters associated with the operation of a plurality of electrical components such as a plurality of electrical transformers. The computer system is configured to automatically and continuously correlate the data from the on-line sensors with data from various off-line databases and supervisory networks associated with monitoring the operation of the power distribution network, so as to generate dynamic operating condition assessments, including risk of failure assessments, of each of the monitored electrical components.

The invention discloses a safety evaluation method for the shortcomings of a high temperature production device or part, comprising the steps as follows: a creep strain-time curve of the material of the high temperature production device or part at a particular temperature is obtained, and an isochronous stress-strain curve corresponding to the particular time is established based on the creep strain-time curve; a failure assessment curve chart related to time is established; and a parameter Kr which can determine and reflect the cracking failure degree of the part and a parameter Lr which can determine and reflect the ultimate load failure degree of the part are counted; and finally the parameters(Kr and Lr) are put into the failure assessment chart as state points for comparing so as to determine the failure assessment point and judge the safety of the failure assessment point. The method can be used for analyzing the safety of the shortcomings during the production process and the use process of the high temperature production device or part, thereby avoiding unnecessary maintenance and premium, and further increasing the rationality of making maintenance plans for high temperature production devices.

The invention discloses a residual intensity and residual life computing method for pipe gallery pipelines. The residual intensity and residual life computing method comprises the following steps: collecting the data information of defects of the pipe gallery pipelines; judging the defects are plane type defects or volume type defects; for the plane type defects, obtaining the engineering stress-strain curve of a defect pipeline material from the data information of the defects of the pipe gallery pipelines, determining a failure assessment diagram, and then computing assessment points to obtain the residual intensity of the pipe gallery pipelines; for the volume type defects, obtaining the design factors, the weld joint factors and the minimum measurement wall thickness from the data information of the defects of the pipe gallery pipelines, and obtaining the residual intensity of the pipe gallery pipelines through computing; computing basic numerical values according to the data information of the defects of the pipe gallery pipelines, and computing the residual lives of the pipe gallery pipelines according to a maximum value distribution probability density function, a reliability function, maximum corrosion depth point estimation and maximum likelihood estimation. Therefore, the residual intensity and residual lives of the pipelines in a pipe gallery area are effectively and accurately computed and predicted.

The invention relates to a high-level assessment method for defects of a welding joint area at a piping safety end of a pressure vessel of an AP1000 nuclear reactor. The method comprises the following steps of: characterizing the detected dimensions of unpenetrated circumferential inner surface defects; establishing a failure assessment graph, wherein the failure assessment graph comprises the family of the failure assessment curves of the unpenetrated circumferential inner surface defects in the different dimensions, which are acquired on the basis of three-dimensional finite element calculation; selecting the failure assessment curves according to the dimensions of the defects; based on the three-dimensional finite element calculation, calculating the family of the curves that stress intensity factors change along an extra resultant bending moment at the deepest points of the unpenetrated circumferential inner surface defects in the different dimensions; determining the stress intensity factors according to the resultant bending moment and the dimensions of the defects; calculating a specific breaking strength parameter Kr; based on the three-dimensional finite element calculation, acquiring the family of the ultimate load bending moment curves of the unpenetrated circumferential inner surface defects in the different dimensions; determining ultimate load bending moments according to the dimensions of the defects; calculating a load ratio parameter Lr; and marking a calculated coordinate (Lr, Kr) on the failure assessment graph, and judging whether falling into an area which is encircled by the selected failure assessment curves, a vertical end line and coordinate axes or not.

The invention discloses a photovoltaic module failure assessment and prediction method based on an accelerated test chamber. The failure probability of the module in different accelerated test stagesfor a prediction module can be assessed by using Weibull distribution and an obtained Weibull distribution function. The reliability of a photovoltaic module in a temperature and humidity circulationaccelerated test is assessed by using the Weibull distribution function, and the reliability of the module is assessed by using a reliability function for Weibull distribution. The current situation that the present reliability assessment method for a module accelerated test can be changed, the application of the reliability of the method for Weibull distribution in the module accelerated test andthe failure probability thereof is proposed through analysis for accelerated test data; and through the method, the failure probability of the photovoltaic module in different stages of the accelerated test can be obtained, and thus the reliability of the photovoltaic module in the accelerated test is assessed, so that certain reference significance is provided for predicting the service life ofthe photovoltaic module.

A method for leak-before-rupture assessment including using a failure assessment diagram (FAD) assessment curve from a crack initiation based FAD analysis to analyze a crack in a material; and using a ductile tearing analysis in conjunction with the FAD assessment curve to detect a crack exhibiting at least one of ductile tearing stability and tearing instability prone to rupture during growth of the crack.

The invention relates to a reservoir group outlet structure failure assessment method based on the Bayesian network. The reservoir group outlet structure failure assessment method includes the steps of establishing a Bayesian network topological structure, determining respective probability, calculating spillway system failure probability, and calculating the integral failure probability. The Bayesian network for failure probability determination is combined with a conventional event tree for determining stepped reservoir group spillway facility failure, and calculating the probability of downstream control step failure caused by upstream dam bursting flood is added as needed to form a complete Bayesian spillway facility failure assessment network. A reservoir group outlet structure failure is a complex multivariable system, and the assessment system can be used to analyze common cause failure and conduct backward inference. The assessment system can scientifically determine the value of information and determine whether new information needs to be acquired, so that the outlet structure failure analysis is gradually improved and becomes more scientific.

The invention provides a cooling system of a power battery pack for a vehicle. The power battery pack comprises a power battery pack casing in which the power battery pack is positioned. The cooling system comprises a cooling liquid storing device, at least one nozzle and a cooling liquid pipeline which is used for connecting the cooling liquid storing device with the nozzle, wherein the nozzle is positioned in the power battery pack casing, faces the surface of the power battery pack and is started when a failure assessment parameter of the power battery pack meets a preset starting condition, so that a liquid in the cooling liquid storing device can be sprayed to the power battery pack. As the cooling system is used, a large amount of heat is adsorbed via liquid gasification, so that the power battery pack in failure can be cooled. Thus, the safety of the vehicle is ensured.

The invention discloses a judgement method for a cutter failure. The method comprises the steps that a current sensor is used for collecting a current signal of a main shaft of a processing machine table, and the current signal is repeatedly sampled with 1 s as time length, marked and labelled; through feature learning, a feature value of the current signal is extracted; according to the feature value of the current signal, current signal data is cleaned, the cleaned signal is subjected to normalization, and input data is obtained; through machine learning and depth learning methods, the relation between the current signal and cutter breaking and cracks is analyzed, the input data is used as a training sample for training, and then a cutter failure judgement model is established; the inputdata is used as a testing sample to be input into the cutter failure judgement model testing, and a cutter failure assessment result is obtained. According to the judgement method for the cutter failure, cutter wear can be effectively monitored and predicted online in real time, the cutter failure states of various related factors including cutter breaking and edge cracking are predicted in advance, hidden safety dangers in the production process are greatly reduced, and the finished product rate of products is increased.

The present invention relates to a leak before burst (LBB) analysis method based on a failure assessment diagram (FAD). The method comprises the following steps: (a) service state analysis; (b) initial crack selection; (c) load analysis; (d) line elastic stress intensity factor (SIF) calculation; (e) ultimate load analysis; (f) evaluation point coordinate calculation; (g) FAD selection; (h) evaluation point drawing; (i) elastoplastic SIF calculation; (j) J-integral calculation; (k) calculation and fitting of the J-integral of different cracks; (l) calculation of the structural failure criticalcrack size; (m) calculation of the structural critical leakage crack size; and (n) LBB criterion evaluation. According to the method provided by the present invention, based on the FAD theory, defects that the theoretical basis of elastoplastic analysis in the existing norms is insufficient, the existing J-integral calculation manual has a limited application scope, the finite element modeling analysis process is complicated, and the processes for calculating the structural failure critical crack size and the structural critical leakage crack size are complicated, and the like are overcome, and a FAD-based LBB analysis basis is provided.

The invention provides a dynamic stretching failure assessment method for a fiber reinforced composite material. For the problem of lack of a theoretical basis due to no consideration of a strain rateeffect and dependency on test data in correction in an existing fiber reinforced composite material failure assessment method, based on an energy density theory, the strain rate effect of the fiber reinforced composite material under the action of a dynamic load is considered, and derivation is performed to obtain a strain rate related distortion energy density equation of the material under theaction of the dynamic stretching load; the method can accurately analyze a stretching failure behavior of the fiber reinforced composite material under the action of the dynamic load; a large amount of dynamic tests are avoided; and the reliable assessment method is provided for design of various fiber reinforced composite structures.

The invention discloses an evaluation method used for the residual intensity of an X80 pipeline circumferential weld crack type defect. The evaluation method comprises the following steps that: 1) calculating the loading ratio of an X80 pipeline to be evaluated, and calculating the ductility ratio of the X80 pipeline to be evaluated, wherein the X80 pipeline to be evaluated is provided with the circumferential weld crack type defect; 2) according to the loading ratio and the ductility ratio of the X80 pipeline to be evaluated, drawing a data point in a coordinate system; and 3) constructing the critical failure assessment curve of an X80 pipeline circumferential weld sample, inserting the critical failure assessment curve of the X80 pipeline circumferential weld sample into a coordinate system in the 2), and evaluating the residual intensity of the circumferential weld crack type defect of the X80 pipeline to be evaluated according to the critical failure assessment curve of the X80 pipeline circumferential weld sample and the position relationship of the data point in the 2). By use of the method, the evaluation of the residual intensity of the X80 pipeline circumferential weld crack type defect can be realized.

The invention discloses a method for measuring full-length cohesive soil anchorage de-bonding length and dynamic anchorage force. The measuring method is mainly characterized in that based on advantageous shear failure characteristics of an anchorage soil interface, a de-bonding length change value of an anchorage structure is determined according to a total displacement composition of an anchorage body when a rod body is completely coupled with the anchorage body, anchorage soil interface shearing stress index attenuation characteristics and slippage failure assessment thereof, and dynamic anchorage force is further obtained. The method can be used for performing dynamic monitoring, anchorage effect assessment and anchorage reinforcement on anchorage force, so that disasters are reduced; moreover, a monitoring process and a calculating process are clear, operation is simple and convenient, environmental adaptation is strong and cost is low, so that the problem that anchorage force fixation as well as a complex dynamic monitoring technology thereof and reinforcing grouting amount depend on experience is overcome, and better theoretical significance and a higher economic value are shown, and therefore, practice can be guided better.

The invention discloses an evaluation method of the fatigue properties of metal materials, and belongs to the technical field of material science and engineering application. The evaluation method ischaracterized in that based on material fatigue life data, a service working condition and safety indexes, a fatigue failure evaluation curve is developed, a safety region, a failure region and an intermediate region or an intersecting region can be divided by a stress/strain range, and the fatigue properties of different materials can be compared through calculation of equivalent safety area. According to a technology disclosed by the invention, the problems that the fatigue properties of different materials are scattered, and direct comparison cannot be carried out are solved; the new technology has the advantages that the evaluation is rapid and the application is simple, and can be widely applied to compare and evaluate the fatigue properties of different metal materials.

The invention discloses an R6-FAD and BP-MCS-based fuzzy random reliability evaluation method for a pipeline with crack defects, and the method combines a BP neural network and Monte Carlo simulation based on a failure evaluation diagram of an R6 specification, and is applied to the fuzzy random reliability evaluation of the pipeline with the crack defects. The method mainly comprises the following steps: step 1, inputting probability distribution types and parameters of actual working condition load, crack defect size and material performance and maximum simulation times N, and establishing a fuzzy limit state equation; 2, determining basic parameters, and constructing an initialized BP neural network; 3, training a neural network to ensure that the neural network can better approach a fuzzy limit state equation; and 4, random sampling being carried out, and a Monte Carlo principle being used to calculate a failure probability and a reliability index. According to the method, the fuzzy reliability randomization process can be simplified, and a numerical solution with relatively high simulation precision can be obtained; meanwhile, the fuzzy random coupling uncertainty of the structure is considered, the method is better in line with engineering practice, and the method has guiding significance for safety assessment of the structure.

Provided is a failure sensing device (8) comprising a state information acquisition part (21), a failure assessment part (23), and a failure information output part (24). The state information acquisition part (21) acquires, from a remote monitoring system (3) for monitoring remotely disposed facilities (21-26), state information indicating the state of the remote monitoring system (3). On the basis of the state information acquired by the state information acquisition part (21), the failure assessment part (23) assesses a failure of the remote monitoring system (3), and generates failure information indicating details of the assessed failure. The failure information output part (24) outputs the failure information generated by the failure assessment part (23).

The invention relates to the technical field of ultrahigh pressure vessel design and development and fatigue failure evaluation calculation, in particular to a method for calculating an axial-radial crack stress intensity factor of the outer wall of an ultrahigh pressure vessel cylinder. The method comprises the following steps: determining structural parameters of an ultrahigh pressure vessel, measuring shape parameters of axial-radial cracks, and determining a load working condition of a cylinder; fitting stress distribution perpendicular to a plane where the crack is located; calculating a required fitting coefficient; calculating another fitting coefficient under the current crack shape; calculating crack shape coefficients at the deepest point of the current crack and the position close to the free surface; and calculating a stress intensity factor KI. According to the method, the accuracy of a calculation result can be ensured, meanwhile, rapid, concise and written calculation of the axial-radial semi-elliptical crack stress intensity factor of the outer wall of the cylinder can be achieved only through a formula, finite element calculation software and professional mathematical analysis software do not need to be relied on, and the method is more suitable for engineering application.

Provided is a boiler 'four tubes' failure evaluation method based on field state inspection parameters, comprising the steps of determining the basic information of an evaluation object and evaluation points and the life cycle stage of the evaluation object, calculating a failure probability factor corresponding to the life cycle stage, acquiring field state inspection parameters according to an inspection scheme, calculating the failure probability caused by each parameter, evaluating the failure probability of each evaluation point on the basis, and finally, evaluating the failure probability of parts. According to the invention, there is neither need for evaluation personnel to have abundant life evaluation knowledge and experience nor need to bear additional test cost, the failure probability can be evaluated only by acquiring the field state inspection parameters of 'four tubes' of a boiler, and therefore, technicians in coal-fired power plants are directly helped to make repair and replacement strategies.