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CN111444645B - Harbor machine damage positioning method based on residual stress gap state - Google Patents

Harbor machine damage positioning method based on residual stress gap state Download PDF

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CN111444645B
CN111444645B CN202010159712.3A CN202010159712A CN111444645B CN 111444645 B CN111444645 B CN 111444645B CN 202010159712 A CN202010159712 A CN 202010159712A CN 111444645 B CN111444645 B CN 111444645B
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residual stress
vulnerable
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gap state
port machine
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朱林
周萌
王鹏
黄嘉铭
邱建春
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Yangzhou University
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01LMEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L1/00Measuring force or stress, in general
    • G01L1/25Measuring force or stress, in general using wave or particle radiation, e.g. X-rays, microwaves, neutrons
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01LMEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L5/00Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
    • G01L5/0047Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes measuring forces due to residual stresses
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N23/00Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00Technologies related to metal processing
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Abstract

The invention discloses a port machine damage positioning method based on a residual stress gap state, which comprises the following steps: s1, determining the vulnerable position of a port machine structure; s2, determining a real-time maximum residual stress interval value of a vulnerable position of the port machine; s3, calculating a port machine real-time residual stress gap state value; s4, determining a gap state factor of each vulnerable position; s5, port machine damage positioning based on residual stress gap state. The method has high detection precision and has important practical significance for realizing damage positioning of port machines.

Description

Harbor machine damage positioning method based on residual stress gap state
Technical Field
The invention relates to a port machine damage positioning method, in particular to a port machine damage positioning method based on a residual stress gap state.
Background
With the development of society and the deepening of international trade cooperation, port machines have become increasingly important tools for deepening the cooperation between ports of two countries. The port crane is an important mechanized tool for lifting cargoes at ports, and the damage condition of the structure of the port crane becomes the focus of a user and a detector along with the increase of the throughput of cargoes and the extreme change of the working load, and is also the focus of research at home and abroad. At present, most of damage positioning methods are developed based on sound vibration characteristics collected under working conditions, are greatly influenced by working condition environments, and the damage positions of the port machine structure cannot be fully reflected by the differences among different sound vibration characteristic indexes, so that how to accurately position the damage positions from the intrinsic performance of the port machine structure reflected by the port machine structure under the loaded action is a common problem in the research field.
Disclosure of Invention
The invention aims to: the invention aims to provide a port machine damage positioning method based on a residual stress gap state.
The technical scheme is as follows: the invention provides a port machine damage positioning method based on a residual stress gap state, which comprises the following steps:
s1, determining the vulnerable position of a port machine structure;
s2, determining a real-time maximum residual stress interval value of a vulnerable position of the port machine;
s3, calculating a port machine real-time residual stress gap state value;
s4, determining a gap state factor of each vulnerable position;
s5, port machine damage positioning based on residual stress gap state.
Further, the determining method in the step S1 is as follows: the method comprises the steps of importing a finite element analysis model of the whole port machine into finite element analysis software, meshing the finite element analysis model, setting constraint conditions and applying load conditions according to actual working conditions of the port machine, performing post-processing on the finite element analysis model of the port machine, determining each vulnerable position of a port machine structure under the actual working conditions, and marking the position m=1, 2 and 3 according to analysis results on the model.
Further, the determining method in the step S2 is as follows: combining the vulnerable positions of the port machine structure under the multiple actual working conditions determined in the step S1, finding the positions of the marks on the actual port machine structure, arranging an X-ray residual stress tester at the corresponding positions, and measuring the corresponding residual stress value sigma of each second according to the time interval of 1 minute mt Measurements were taken and the ith minute was calculatedEquivalent interval value q of structural residual stress value of m-number position im I represents a minute mark,
Figure BDA0002404614650000021
wherein ,qim The equivalent interval value of the structural residual stress of the ith minute of the m-number damaged position; c (sigma) mt ) max The maximum of all residual stress values measured per minute for the mth vulnerable site; c (sigma) mt ) min The minimum of all residual stress values measured per minute for the mth vulnerable site;
Figure BDA0002404614650000022
the average value of all residual stress values measured in the mth vulnerable position per minute; t is a number of seconds per minute,
Figure BDA0002404614650000023
real-time q under actual working condition im And performing calculation and recording.
Further, the calculation method in step S3 is as follows: combining the residual stress equivalent interval value q of each damage position calculated in S2 im Maximum value C (q im ) max And a minimum value C (q im ) min Identifying and recording each lesion location corresponding to C (q im ) max Time point of (C) is C (t m ) max And corresponds to C (q im ) min Time point of (C) is C (t m ) min And further calculate the residual stress gap state value J of each vulnerable position on the basis m
Figure BDA0002404614650000024
wherein ,tm Total monitoring time for each lesion site; q im Residual stress equivalent interval values of all damage positions are obtained; j (J) m A residual stress gap state value for each vulnerable location; epsilon is the complex directional gap homogenization factor; gamma is the singular coefficient of the injury position; c (q) im ) max The maximum value of the residual stress equivalent interval value of each damage position in the monitoring time is obtained; c (q) im ) min For the minimum value of the residual stress equivalent interval value of each damage position in the monitoring time,
Figure BDA0002404614650000025
Figure BDA0002404614650000026
further, the method determined in S4 is as follows: based on the real-time residual stress gap state value of the port machine calculated in the step S3, the corresponding residual stress gap state value J of each vulnerable position is calculated m Substituting the gap state factor value Y for each position as follows m The calculation is performed such that,
Figure BDA0002404614650000027
wherein ,Ym A gap state factor value for each location; j (J) m A residual stress gap state value for each vulnerable location; c (J) m ) max A maximum value of the residual stress gap state value for each vulnerable location; c (J) m ) min A minimum value of residual stress gap state values for each vulnerable location; gamma is the singular coefficient of the lesion location.
Further, the method for positioning in S5 is as follows: on the basis of S4, all gap state factor values Y are extracted m In excess of 1.73
Figure BDA0002404614650000031
I.e. the location in the port machine where the potential damage has occurred,
Figure BDA0002404614650000032
wherein ,
Figure BDA0002404614650000033
the average value of gap state factor values of all vulnerable positions; y is Y m A gap state factor value for each location; m is the number of vulnerable positions; n is the number of vulnerable positions.
The beneficial effects are that: the method can realize the acquisition of the real-time residual stress gap state of the port machine under the working condition, and the main damage interval is determined through the cis-position relation of the gap state factors, so that the damage extreme value is determined by means of the cis-position factors, the real-time determination of the specific damage position in the working process of the port crane is facilitated, and the positioning precision of the damage position of the port mechanism is effectively improved.
Drawings
FIG. 1 is a flow chart of the method of the present invention.
Detailed Description
As shown in fig. 1, the method for positioning port machine damage based on the residual stress gap state of the present embodiment includes the following steps:
s1, determining the vulnerable position of a port machine structure:
the method comprises the steps of importing a port machine integral finite element analysis model into ANSYS finite element analysis software, meshing the port machine integral finite element analysis model, setting constraint conditions and applying load conditions according to actual working conditions of the port machine, performing post-processing on the port machine finite element analysis model, determining each vulnerable position of a port machine structure under the actual working conditions, and marking the position on the model according to analysis results, wherein the marking position is m (m=1, 2, 3.).
S2, determining the real-time maximum residual stress interval value of the vulnerable position of the port machine:
binding S1 is confirmedThe method comprises the steps of determining vulnerable positions of a port machine structure under a plurality of actual working conditions, finding positions of marks on the actual port machine structure, arranging an X-ray residual stress tester at corresponding positions, and measuring corresponding residual stress value sigma per second according to a time interval of 1 minute mt Measuring and calculating the equivalent interval value q of the structural residual stress value at the position of the m-th minute im (i represents a minute mark).
Figure BDA0002404614650000034
wherein ,qim The equivalent interval value of the structural residual stress value of the m-number damage position at the ith minute; c (sigma) mt ) max The maximum of all residual stress values measured per minute for the mth vulnerable site; c (sigma) mt ) min The minimum of all residual stress values measured per minute for the mth vulnerable site;
Figure BDA0002404614650000041
the average value of all residual stress values measured in the mth vulnerable position per minute; t is seconds per minute.
Figure BDA0002404614650000042
Real-time q under actual working condition im And performing calculation and recording.
S3, calculating a real-time residual stress gap state value of the port machine:
combining the residual stress equivalent interval value q of each damage position calculated in S2 im Maximum value C (q im ) max And a minimum value C (q im ) min Identifying and recording each lesion location corresponding to C (q im ) max Time point of (C) is C (t m ) max And corresponds to C (q im ) min Time point of (C) is C (t m ) min
And further calculate the residual stress gap state value J of each vulnerable position on the basis m
Figure BDA0002404614650000043
wherein ,tm Total monitoring time for each lesion site; q im Residual stress equivalent interval values of all damage positions are obtained; j (J) m A residual stress gap state value for each vulnerable location; epsilon is the complex directional gap homogenization factor; gamma is the singular coefficient of the injury position; c (q) im ) max The maximum value of the residual stress equivalent interval value of each damage position in the monitoring time is obtained; c (q) im ) min And (5) the minimum value of the residual stress equivalent interval value in the monitoring time is set for each damage position.
Figure BDA0002404614650000044
Figure BDA0002404614650000045
S4, determining a gap state factor of each vulnerable position:
based on the real-time residual stress gap state value of the port machine calculated in the step S3, the corresponding residual stress gap state value J of each vulnerable position is calculated m Substituting the gap state factor value Y for each position as follows m And (5) performing calculation.
Figure BDA0002404614650000046
wherein ,Ym A gap state factor value for each location; j (J) m A residual stress gap state value for each vulnerable location; c (J) m ) max Maximum value of residual stress gap state value for each vulnerable position;C(J m ) min A minimum value of residual stress gap state values for each vulnerable location; gamma is the singular coefficient of the lesion location.
S5, port machine damage positioning based on residual stress gap state:
on the basis of S4, all gap state factor values Y are extracted m Is in excess of
Figure BDA0002404614650000051
I.e. the location in the port machine where the potential damage has occurred.
Figure BDA0002404614650000052
wherein ,
Figure BDA0002404614650000053
the average value of gap state factor values of all vulnerable positions; y is Y m A gap state factor value for each location; m is the number of vulnerable positions; n is the number of vulnerable positions.

Claims (3)

1. A port machine damage positioning method based on a residual stress gap state is characterized by comprising the following steps of: the method comprises the following steps:
s1, determining the vulnerable position of a port machine structure;
s2, determining a real-time maximum residual stress value of a vulnerable position of the port machine;
s3, calculating a port machine real-time residual stress gap state value;
s4, determining a gap state factor of each vulnerable position;
s5, port machine damage positioning based on residual stress gap state,
the calculation method in the step S3 is as follows: combining the residual stress equivalent interval value q of the m number vulnerable position calculated in S2 at the ith minute im Maximum value C (q im ) max And a minimum value C (q im ) min Identifying and memorizingRecording each vulnerable position corresponding to C (q im ) max Time point of (C) is C (t m ) max And corresponds to C (q im ) min Time point of (C) is C (t m ) min And further calculate the residual stress gap state value J of each vulnerable position on the basis m
Figure FDA0004192866060000011
wherein ,tm Total monitoring time for each vulnerable site; q im The residual stress equivalent interval value of each vulnerable position is used; j (J) m A residual stress gap state value for each vulnerable location; epsilon is the complex directional gap homogenization factor; gamma is the singular coefficient of the vulnerable position; c (q) im ) max The maximum value of the residual stress equivalent interval value of each vulnerable position in the monitoring time is set; c (q) im ) min For the minimum value of the residual stress equivalent interval value of each vulnerable position in the monitoring time,
Figure FDA0004192866060000012
Figure FDA0004192866060000013
the method determined in S4 is as follows: based on the real-time residual stress gap state value of the port machine calculated in the step S3, the corresponding residual stress gap state value J of each vulnerable position is calculated m Substituting the gap state factor value Y for each position as follows m The calculation is performed such that,
Figure FDA0004192866060000014
wherein ,Ym For each positionA gap state factor value of (2); j (J) m A residual stress gap state value for each vulnerable location; c (J) m ) max A maximum value of the residual stress gap state value for each vulnerable location; c (J) m ) min A minimum value of residual stress gap state values for each vulnerable location; gamma is the singular coefficient of the vulnerable position,
the positioning method in S5 is as follows: on the basis of S4, all gap state factor values Y are extracted m Is in excess of
Figure FDA0004192866060000021
I.e. the location in the port machine where the potential damage has occurred,
Figure FDA0004192866060000022
wherein ,
Figure FDA0004192866060000023
the average value of gap state factor values of all vulnerable positions; y is Y m A gap state factor value for each location; m is the number of vulnerable positions; n is the number of vulnerable positions.
2. The port machine damage positioning method based on the residual stress gap state according to claim 1, wherein: the determining method in the step S1 is as follows: the method comprises the steps of importing a finite element analysis model of the whole port machine into finite element analysis software, meshing the finite element analysis model, setting constraint conditions and applying load conditions according to actual working conditions of the port machine, performing post-processing on the finite element analysis model of the port machine, determining each vulnerable position of a port machine structure under the actual working conditions, and marking the position m=1, 2 and 3 according to analysis results on the model.
3. The residual stress gap condition based on claim 1The method for positioning the damage of the port machine is characterized by comprising the following steps of: the determining method in the step S2 is as follows: combining the vulnerable positions of the port machine structure under the multiple actual working conditions determined in the step S1, finding the positions of the marks on the actual port machine structure, arranging an X-ray residual stress tester at the corresponding positions, and measuring the corresponding residual stress value sigma of every second in the ith minute according to the time interval of 1 minute mt Measuring and calculating the equivalent interval value q of the structural residual stress value at the position of the m-th minute im I represents a minute mark,
Figure FDA0004192866060000024
wherein ,qim The equivalent interval value of the structural residual stress of the m-number vulnerable position at the ith minute; c (sigma) mt ) max The maximum of all residual stress values measured per minute for the mth vulnerable site; c (sigma) mt ) min The minimum of all residual stress values measured per minute for the mth vulnerable site;
Figure FDA0004192866060000025
the average value of all residual stress values measured in the mth vulnerable position per minute; t is a number of seconds per minute,
Figure FDA0004192866060000026
real-time q under actual working condition im And performing calculation and recording.
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