Patent classifications
G01N2203/0071
CREEP STRENGTH ANALYSIS AND ASSESSMENT METHOD AND COMPUTER DEVICE
A creep strength analysis and assessment method includes comparing whether a maximum value of a local strain and a membrane strain are less than a corresponding allowable strain, and if less, determining that a component is safe; otherwise, performing the following steps: performing stress linearization on a path to obtain a local primary membrane stress P.sub.L and a local primary bending stress P.sub.b; averaging shear stress components on the path to obtain an average shear stress τ.sub.m; obtaining a strength limit S.sub.mt, a time-independent minimum stress strength value S.sub.m and a temperature- and time-dependent stress strength limit S.sub.t for a given material, a design lifetime and a design temperature; comparing whether P.sub.L, P.sub.L+P.sub.b and P.sub.L+P.sub.b/K.sub.t are less than S.sub.mt, KS.sub.m and S.sub.t; and comparing whether τ.sub.m is less than 0.6S.sub.m and 0.6S.sub.t, and if less, the component is safe, otherwise, the component is unsafe.
SYSTEM AND METHODS FOR SIMULATION OF MEDICAL DEVICES
Disclosed herein are devices and methods for generating and/or verifying a predictive temperature stress and time creep modulus, approving or rejecting a medical device, verifying a medical device design using a linear device model, and generating coefficients using thermal analysis.
METHOD FOR COMPILING EQUIVALENT ACCELERATION SPECTRUM OF CREEP UNDER VARIABLE TEMPERATURES AND LOADS
Disclosed is a method for compiling an equivalent acceleration spectrum of creep under variable temperatures and loads. The method includes following steps: respectively carrying out a material high-temperature tensile test, material high-temperature creep tests and creep tests under two-stage variable temperatures and loads, and calculating values of a parameter p in a creep damage accumulation model under two-stage variable temperatures and loads; based on a nonlinear damage accumulation model under multi-stage variable temperatures and loads, calculating a damage D caused by a multi-stage variable temperatures and loads creep load spectrum by utilizing values of parameter p; based on the principle of consistency of damage D, transforming the multi-stage variable temperatures and loads creep load spectrum into an equivalent acceleration spectrum of a first-order maximum creep load, and finally compiling the equivalent acceleration spectrum of creep under variable temperatures and loads.
Dual-criterion diagram methods for designing and assessing the life and strength of high-temperature rotating components
The disclosure relates to a dual-criterion diagram for designing and assessing the life and strength of high-temperature rotating components and its establishment. In addition, the disclosure relates to a method for designing and assessing the life and strength of high-temperature rotating components based on the dual-criterion diagram for designing and assessing the life and strength of high-temperature rotating components. The advantages of the disclosure include a simple design and assessment process, high operability, and reliable assessment results. The invention is expected to be applied finally to assessment and evaluation of high-cycle fatigue life of rotating components at high temperatures.
Method for evaluating and preventing creep damage to conductivity of hydraulic fracture in gas reservoirs
The present invention discloses a method for evaluating and preventing creep damage to conductivity of hydraulic fracture in gas reservoirs, comprising: (1) selecting a rock sample of target reservoir for creep experiment, and plotting ε-t curve of the rock sample during creep; (2) fitting the fractional Kelvin model with the ε-t curve of the rock sample during creep; (3) calculating the conductivity and permeability of hydraulic fracture considering creep damage; (4) numerically solving the productivity model, calculating the cumulative gas production of the gas well produced up to time t, and calculating the creep damage rate for cumulative production of the gas well; (5) repeating Steps (3) to (4), calculating the creep damage rate for cumulative production for the cases of hydraulic fracture sanding concentration N of 5 kg/m.sup.2, 7.5 kg/m.sup.2, 10 kg/m.sup.2, 12.5 kg/m.sup.2 and 15 kg/m.sup.2 respectively, plotting the creep damage chart of cumulative production.
METHOD FOR PREDICTING A CREEP FRACTURE BEHAVIOR OF WOVEN CERAMIC MATRIX COMPOSITE MATERIAL CONSIDERING RANDOM LOAD EFFECT
A method for predicting a creep fracture behavior of a woven ceramic matrix composite is provided. A fiber axial stress distribution equation is obtained according to a shear lag model, a random matrix cracking model, a fracture mechanical interface debonding criterion and a fiber failure model; a matrix crack spacing equation is obtained according to the random matrix cracking model; an interface debonding length equation is obtained according to the fracture mechanics interface debonding criterion, and an equation of the load bearing relationship between intact fibers and broken fibers and a fiber fracture probability equation are obtained based on an overall load bearing criterion; and at last a creep strain equation of the woven ceramic matrix composite material is obtained, according to the overall load bearing criterion, to predict the creep fracture behavior of the woven ceramic matrix composite material affected by the random load.
COMPRESSIVE CREEP FLOW DETERMINATION IN FLUIDS
The present disclosure provides an apparatus and method of use thereof for compressive creep testing of materials in the presence of fluids. The apparatus includes a cantilever arm connected on a first end to a cantilever pivot and including a weight holder on a second end; a first platen connected to the cantilever arm via a swivel located between the first end and the second end; a reservoir; and a second platen disposed within the reservoir and positioned to secure a sample between the first platen and the second platen when a force is applied via the weight holder and the first platen to a sample. Electrical properties of the material can be monitored and measured during the compression creep testing.
Integrated Shape/Property Control Method for Hot Power Spinning of a Cylindrical Part Based on Hot Processing Map
Provided is an integrated shape/property control method for hot power spinning of a cylindrical part based on a hot processing map. The method comprises: during the process of thermoplastic forming of a difficult-to-deform metal, performing a high-temperature mechanical property test on the metal material at a temperature and a strain rate range where dynamic recrystallization occurs; constructing, based on the power dissipation during the thermoplastic forming and a judging criterion for flow instability and on a flow stress-strain relation obtained from the high-temperature mechanical property test, power dissipation maps and flow instability maps at different strains, respectively; combining the power dissipation maps with the flow instability maps to obtain a hot processing map of the material; according to a profile of a power dissipation rate factor η and the flow instability criterion, obtaining potential dangerous forming conditions met with the flow instability criterion, and safe forming conditions under which the power dissipation rate factor η is large and the thermoplastic forming is facilitated; and finally performing hot power spinning of the cylindrical part at the temperature and strain rate that facilitates the thermoplastic forming of the material according to the hot processing map.
TENSILE TESTING MACHINE
A tensile testing machine comprising a test specimen whose elongation is to be measured along a tensile axis, slide plates, an intermediate plate, and first and second parallel guide rods, which freely guide the slide plates axially past them.
APPARATUS STATE ESTIMATION DEVICE, APPARATUS STATE ESTIMATION METHOD AND PROGRAM
A state quantity acquisition unit acquires a state quantity of a target apparatus including a temperature of the target apparatus. A load specification unit specifies a load history of the target apparatus, based on the state quantity. A remaining life calculation unit calculates a parameter related to a remaining life of the target apparatus for each of a plurality of degradation types, based on the load history specified by the load specification unit.