CN106226166A - A kind of fatigue test method measuring antifreeze plate service life - Google Patents

Abstract

This invention provides a fatigue test method for measuring the service life of a magnetic shielding sheet, characterized by the following steps: performing numerical modeling analysis on the entire control rod drive mechanism; performing numerical modeling analysis on the designed bending equivalent fatigue test device for the magnetic shielding sheet; comparing the results of the two analyses; conducting fatigue tests based on the bending equivalent fatigue test device, and plotting the relationship curve. The fatigue test method for measuring the service life of a magnetic shielding sheet provided by this invention solves the problem that the failure process of the magnetic shielding sheet under the actual working state of the control rod drive mechanism cannot be directly observed and measured. Through numerical modeling analysis and verification, the bending equivalent fatigue test method analyzes and studies the failure mechanism of the magnetic shielding sheet under the impact of the armature and makes a prediction of the fatigue life of the magnetic shielding sheet.

Description

A Fatigue Test Method for Measuring the Service Life of Magnetic Isolation Sheet

technical field

The invention relates to the field of nuclear power engineering, in particular to a fatigue test method for measuring the warping fatigue performance and service life of a magnetic spacer in a control rod drive mechanism of a nuclear power plant.

Background technique

The AP1000 Control Rod Drive Mechanism (CRDM) is an electromagnetically actuated mechanical device. In PWRs, the role of the control rod drive mechanism is to position the control rod assembly in the vertical direction. The control rod drive mechanism changes or maintains the vertical height of the control rod assembly to realize the start and stop of the nuclear reactor, adjust or maintain the power level of the core during normal operation of the reactor, and quickly shut down the reactor under accident conditions. It is one of the key equipment that directly affects the normal operation, safety and reliability of the reactor.

As a key part of the control rod drive mechanism, the magnetic spacer is directly related to the service life of the whole mechanism after its dynamic response after step impact.

In view of the fact that the control rod drive mechanism is a closed cavity as a whole, the existing technology cannot directly detect the loading state and damage of the magnetic isolation sheet under its working state. Life test method.

Contents of the invention

Aiming at the deficiencies of the prior art, the invention proposes a fatigue test method for measuring the service life of a magnetic isolation sheet.

The fatigue test method for measuring the service life of the magnetic isolation sheet includes the following steps:

S1. Carry out numerical modeling analysis on the control rod drive mechanism as a whole, and obtain the first principal stress and bending deflection value generated by the magnetic spacer under the impact of the armature;

S2. Carry out numerical modeling analysis for the design of the magnetic isolation sheet bending equivalent fatigue test device, and obtain the first principal stress and bending deflection value of the magnetic isolation sheet under different bending loads;

S3. Compare the above two analysis results to verify whether the designed bending equivalent fatigue test device can be used to study the fatigue failure mechanism of the magnetic isolation sheet;

S4. Carry out a fatigue test based on a bending equivalent fatigue test device, and draw a relational curve.

Preferably, in the step S1, after proper simplification of the control rod drive mechanism as a whole, a three-dimensional axisymmetric dynamic finite element analysis model is established by using numerical simulation software, and the magnetic separation plate is obtained when the armature impacts at a speed of 0.404m/s. The first principal stress and bending deflection value;

Preferably, in the step S2, the magnetic isolation sheets of different materials are made into uniaxial tensile standard test pieces and subjected to uniaxial tensile tests, and the obtained test data are used in the elastic-plastic analysis process after numerical modeling, and the obtained The first principal stress and bending deflection value of the magnetic spacer when the armature impacts at a speed of 0.404m/s and under different warping loads.

Preferably, in the step S3, according to the magnitude and position of the generated first principal stress and the magnitude of the generated bending deflection, it is verified whether the designed bending equivalent fatigue test device can be used to study the fatigue failure mechanism of the magnetic isolation sheet .

Preferably, in the step S4, a fatigue test is performed based on a bending equivalent fatigue test device, a preload of 0.1KN is applied and a displacement control mode is used to obtain different bending loads and the corresponding fatigue life of the magnetic isolation sheet, so as to draw a relationship curve picture.

Compared with the prior art, the present invention has the following beneficial effects:

1. The fatigue test method for measuring the service life of the magnetic isolation sheet provided by the present invention solves the problem that the damage process of the magnetic isolation sheet cannot be directly observed and measured under the actual working state of the control rod drive mechanism. The effective fatigue test method is used to analyze and study the failure mechanism of the magnetic spacer under the impact of the armature and to predict the fatigue life of the magnetic spacer.

Description of drawings

Fig. 1 is a schematic flow chart of a fatigue test method for measuring the service life of a magnetic isolation sheet according to the present invention.

Fig. 2 is the stress cloud diagram of the magnetic isolation plate obtained by numerical modeling and analysis of the control rod drive mechanism as a whole.

Fig. 3 is the stress nephogram of the magnetic isolation sheet obtained by numerical modeling analysis of the designed magnetic isolation sheet bending equivalent fatigue test device.

Fig. 4 is a diagram of the bending displacement and the first principal stress obtained by performing bending numerical analysis on the 304 stainless steel material in the embodiment.

Fig. 5 is a diagram of the bending displacement and the first principal stress obtained by performing bending numerical analysis on the 625 stainless steel material in the embodiment.

Fig. 6 is the logarithmic relationship between bending displacement and fatigue life obtained by carrying out bending equivalent fatigue test on 304 stainless steel material in the embodiment

Fig. 7 is a graph showing the logarithmic value relationship between bending displacement and fatigue life obtained by carrying out bending equivalent fatigue test on 625 stainless steel material in the embodiment.

detailed description

In order to make the above objects, features and advantages of the present invention more comprehensible, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figure 1-7, the fatigue test method for measuring the service life of the magnetic isolation sheet includes the following steps:

S1. Carry out numerical modeling analysis on the control rod drive mechanism as a whole, and obtain the first principal stress and bending deflection value generated by the magnetic spacer under the impact of the armature;

S2. Carry out numerical modeling analysis for the design of the magnetic isolation sheet bending equivalent fatigue test device, and obtain the first principal stress and bending deflection value of the magnetic isolation sheet under different bending loads;

S3. Compare the above two analysis results to verify whether the designed bending equivalent fatigue test device can be used to study the fatigue failure mechanism of the magnetic isolation sheet;

S4. Carry out a fatigue test based on a bending equivalent fatigue test device, and draw a relational curve.

In the step S1, after proper simplification of the control rod driving mechanism as a whole, a three-dimensional axisymmetric dynamic finite element analysis model is established by using numerical simulation software, and the first main force generated by the magnetic spacer when the armature impacts at a speed of 0.404m/s is obtained. Stress and bending deflection values;

In the step S2, the magnetic isolation sheets of different materials are made into uniaxial tensile standard test pieces and subjected to uniaxial tensile test, and the obtained test data are used in the elastic-plastic analysis process after numerical modeling, and the armature is obtained with a value of 0.404 The first principal stress and bending deflection value of the magnetic isolation sheet under the impact of m/s speed and different warping loads.

In the step S3, according to the magnitude and position of the generated first principal stress and the magnitude of the generated bending deflection, it is verified whether the designed bending equivalent fatigue test device can be used to study the fatigue failure mechanism of the magnetic isolation sheet.

In the step S4, a fatigue test is carried out based on a bending equivalent fatigue test device, a preload of 0.1KN is applied and a displacement control mode is used to obtain different bending loads and the corresponding fatigue life of the magnetic isolation sheet, so as to draw a relational graph.

Compared with the prior art, this embodiment has the following beneficial effects:

1. The fatigue test method for measuring the service life of the magnetic isolation sheet provided in this embodiment solves the problem that the damage process of the magnetic isolation sheet cannot be directly observed and measured under the actual working state of the control rod drive mechanism. The bending after verification through numerical modeling analysis The equivalent fatigue test method is used to analyze and study the failure mechanism of the magnetic spacer under the impact of the armature, and to predict the fatigue life of the magnetic spacer.

Each embodiment in this specification is described in a progressive manner, each embodiment focuses on the difference from other embodiments, and the same and similar parts of each embodiment can be referred to each other. As for the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and for related parts, please refer to the description of the method part.

Those skilled in the art may implement the described functionality using different methods for each particular application, but such implementation should not be considered as exceeding the scope of the present invention.

Obviously, those skilled in the art can make various changes and modifications to the invention without departing from the spirit and scope of the invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and equivalent technologies thereof, the present invention also intends to include these modifications and variations.

Claims (5)

1. the fatigue test method measuring antifreeze plate service life, it is characterised in that comprise the steps:

S1. carry out numerical modeling analysis for CRDM entirety, obtain antifreeze plate by institute under armature percussion The first principal stress produced and sag value；

S2. carry out numerical modeling analysis for designed antifreeze plate bending Equivalent Fatigue assay device, obtain antifreeze plate not Produced first principal stress and sag value under same bending load effect；

S3. above two analysis result being contrasted, whether the bending Equivalent Fatigue assay device designed by checking can be used for The fatigue rupture mechanism of research antifreeze plate；

S4. carry out fatigue test based on bending Equivalent Fatigue assay device, and draw graph of relation.

The fatigue test method in measurement the most according to claim 1 antifreeze plate service life, it is characterised in that described step In S1, after suitably simplifying for CRDM entirety, numerical simulation software is utilized to set up Three-dimensional Axisymmetric dynamic Finite element analysis model, obtains armature and scratches with first principal stress produced by antifreeze plate during 0.404m/s velocity shock and bending Angle value；

The fatigue test method in measurement the most according to claim 1 antifreeze plate service life, it is characterised in that described step In S2, the antifreeze plate of unlike material is fabricated to simple tension code test part and carries out simple tension test, the test obtained Data elastic-plastic analysis process after the numerical modeling, obtains armature with during 0.404m/s velocity shock and different warpage First principal stress produced by antifreeze plate and sag value under load effect.

The fatigue test method in measurement the most according to claim 1 antifreeze plate service life, it is characterised in that described step In S3, according to produced first principal stress size, position and produced sag size, verify designed curved Whether bent Equivalent Fatigue assay device can be used for studying the fatigue rupture mechanism of antifreeze plate.

The fatigue test method in measurement the most according to claim 1 antifreeze plate service life, it is characterised in that described step In S4, carry out fatigue test based on bending Equivalent Fatigue assay device, apply preload 0.1KN and use displacement control mode, To different bending loads and corresponding antifreeze plate fatigue life, to draw graph of relation.