CN111444645A - Port machine damage positioning method based on residual stress gap state - Google Patents
Port machine damage positioning method based on residual stress gap state Download PDFInfo
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- 230000006378 damage Effects 0.000 title claims abstract description 60
- 238000000034 method Methods 0.000 title claims abstract description 30
- 238000012544 monitoring process Methods 0.000 claims description 12
- 238000013461 design Methods 0.000 claims description 6
- 230000003902 lesion Effects 0.000 claims description 6
- 238000004364 calculation method Methods 0.000 claims description 5
- 208000027418 Wounds and injury Diseases 0.000 claims description 3
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- 238000000265 homogenisation Methods 0.000 claims description 3
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
- G01L1/25—Measuring force or stress, in general using wave or particle radiation, e.g. X-rays, microwaves, neutrons
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
- G01L5/0047—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes measuring forces due to residual stresses
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N23/00—Investigating 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
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- Y—GENERAL 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
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
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 position of the port machine structure which is vulnerable to damage; s2, determining a real-time maximum residual stress interval value of a vulnerable position of the port machine; s3, calculating a state value of the real-time residual stress gap of the port machine; s4, determining a clearance state factor of each vulnerable position; and S5, locating the port machine damage based on the residual stress gap state. The method is high in detection precision and has important practical significance for realizing the damage positioning of the port machine.
Description
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 more and more important tools for deepening the cooperation between ports of two countries. The port crane is an important mechanized tool for lifting cargos at a port, and with the increase of cargo throughput and extreme change of working load, the damage condition of the structure of the port crane becomes a key point of attention of users and detection personnel and is also a key point of research at home and abroad. At present, most damage positioning methods are developed based on sound vibration characteristics collected under working conditions, the influence of the working conditions and the environment is large, and the difference between different sound vibration characteristic indexes cannot fully reflect the damage position of a port machine structure, so that the common problem in the research field is how to accurately position the damage position starting from the internal performance of the port machine structure reflected under the loading effect.
Disclosure of Invention
The purpose of the invention is as follows: 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 of:
s1, determining the position of the port machine structure which is vulnerable to damage;
s2, determining a real-time maximum residual stress interval value of a vulnerable position of the port machine;
s3, calculating a state value of the real-time residual stress gap of the port machine;
s4, determining a clearance state factor of each vulnerable position;
and S5, locating the port machine damage based on the residual stress gap state.
Further, the determining method of 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, carrying out gridding division on the finite element analysis model, setting constraint conditions and applying load conditions on the finite element analysis model according to actual working conditions of the port machine, carrying out post-processing on the finite element analysis model of the port machine, determining each vulnerable position of the port machine structure under the actual working conditions, and marking the model according to an analysis result, wherein the marking position is m, m is 1, 2 and 3.
Further, the determining method of step S2 is as follows: combining the vulnerable positions of the port machine structure under the plurality of actual working conditions determined in the 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 residual stress value sigma corresponding to each second according to the time interval of 1 minutemtMeasuring, and calculating an equivalent interval value q of the structure residual stress value at the m position at the ith minuteimAnd i represents a mark of the minute,
wherein ,qimThe equivalent interval value of the structural residual stress at the ith minute of the m-number damage position; c (sigma)mt)maxThe maximum value of all residual stress values measured in every minute at the mth vulnerable position; c (sigma)mt)minThe minimum value of all residual stress values measured in every minute at the mth vulnerable position;
the average value of all residual stress values measured in every minute at the mth vulnerable position; t is a mark of seconds per minute,
real-time q-pair under actual working conditionimAnd calculating and recording.
Further, the calculation method of step S3 is: combining the residual stress equivalent interval values q of each damage position calculated in S2imMaximum value of C (q) over monitoring time for each lesion siteim)maxWith a minimum value of C (q)im)minIdentify and record each lesion location as corresponding to C (q)im)maxAt a time point of C (t)m)maxAnd corresponds to C (q)im)minAt a time point of C (t)m)minAnd further calculating the residual stress gap state value J of each vulnerable position on the basism，
wherein ,tmTotal monitoring time for each injury site; q. q.simThe equivalent interval value of the residual stress of each damage position is obtained; j. the design is a squaremA residual stress gap state value for each vulnerable site; the compound gap homogenization coefficient; gamma is a singularization coefficient of the damage position; c (q)im)maxThe maximum value of the residual stress equivalent interval value of each damage position in the monitoring time is obtained; c (q)im)minThe minimum value of the residual stress equivalent interval value of each damage position in the monitoring time is obtained,
further, the method determined in S4 is: on the basis of the port machine real-time residual stress gap state value calculated in S3, the residual stress gap state value J corresponding to each vulnerable position is calculatedmSubstituting the following equation into the value of the gap state factor Y for each positionmThe calculation is carried out in such a way that,
wherein ,YmA gap state factor value for each position; j. the design is a squaremA residual stress gap state value for each vulnerable site; c (J)m)maxThe maximum value of the residual stress gap state value of each vulnerable position; c (J)m)minFor the stump of each vulnerable siteMinimum value of residual stress gap state value; γ is a singularization coefficient of the damage location.
Further, the method for positioning in S5 is: on the basis of S4, all gap state factor values Y are extractedmIn excess of 1.73
The position of (1), namely the position where the potential damage in the port machine has occurred,
wherein ,
the average value of the gap state factor values of all vulnerable positions is obtained; y ismA gap state factor value for each position; m is the number of the position which is easy to damage; n is the number of vulnerable positions.
Has the advantages that: the method can realize the acquisition of the residual stress clearance state of the port machinery under the working condition in real time, determine the main damage interval through the cis-position relation of the clearance state factors, further determine the damage extreme value quantity according to the cis-position factors, and is favorable for determining the specific damage position in real time in the working process of the port crane, thereby more effectively improving the positioning precision of the damage position of the port mechanism.
Drawings
FIG. 1 is a flow chart of the method of the present invention.
Detailed Description
As shown in fig. 1, the method for locating a port machine damage based on a residual stress gap state in this embodiment includes the following steps:
s1, determining a position where a port machine structure is easily damaged:
importing a finite element analysis model of the whole port machine into ANSYS finite element analysis software, carrying out gridding division on the finite element analysis model, then setting constraint conditions and applying load conditions on the finite element analysis model according to actual working conditions of the port machine, then carrying out post-processing on the finite element analysis model of the port machine, determining each vulnerable position of the port machine structure under the actual working conditions, and marking the model according to an analysis result, wherein the marking position is m (m 1, 2, 3.).
S2, determining a real-time maximum residual stress interval value of a position where a port machine is easily damaged:
combining the vulnerable positions of the port machine structure under the plurality of actual working conditions determined in the 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 residual stress value sigma corresponding to each second according to the time interval of 1 minutemtMeasuring, and calculating an equivalent interval value q of the structure residual stress value at the m position at the ith minuteim(i represents a minute mark).
wherein ,qimThe equivalent interval value of the structure residual stress value of the m-number damage position in the ith minute is shown; c (sigma)mt)maxThe maximum value of all residual stress values measured in every minute at the mth vulnerable position; c (sigma)mt)minThe minimum value of all residual stress values measured in every minute at the mth vulnerable position;
the average value of all residual stress values measured in every minute at the mth vulnerable position; t is seconds per minute.
Real-time q-pair under actual working conditionimAnd calculating and recording.
S3, calculating a state value of the real-time residual stress gap of the port machine:
combining the residual stress equivalent interval values q of each damage position calculated in S2imMaximum value of C (q) over monitoring time for each lesion siteim)maxWith a minimum value of C (q)im)minIdentify and record each lesion location as corresponding to C (q)im)maxAt a time point of C (t)m)maxAnd corresponds to C (q)im)minAt a time point of C (t)m)min。
And further calculating the residual stress gap state value J of each vulnerable position on the basism
wherein ,tmTotal monitoring time for each injury site; q. q.simThe equivalent interval value of the residual stress of each damage position is obtained; j. the design is a squaremA residual stress gap state value for each vulnerable site; the compound gap homogenization coefficient; gamma is a singularization coefficient of the damage position; c (q)im)maxThe maximum value of the residual stress equivalent interval value of each damage position in the monitoring time is obtained; c (q)im)minAnd the minimum value of the residual stress equivalent interval value of each damage position in the monitoring time is obtained.
S4, determining a clearance state factor of each vulnerable position:
on the basis of the port machine real-time residual stress gap state value calculated in S3, the residual stress gap state value J corresponding to each vulnerable position is calculatedmSubstituting the following equation into the value of the gap state factor Y for each positionmAnd (6) performing calculation.
wherein ,YmIn the form of gaps for each positionA value of the state factor; j. the design is a squaremA residual stress gap state value for each vulnerable site; c (J)m)maxThe maximum value of the residual stress gap state value of each vulnerable position; c (J)m)minThe minimum value of the residual stress gap state value of each vulnerable position; γ is a singularization coefficient of the damage location.
S5, carrying machine damage positioning based on the residual stress gap state:
on the basis of S4, all gap state factor values Y are extractedmZhongchao (middle surpass)
I.e. where potential damage has occurred in the port machinery.
wherein ,
the average value of the gap state factor values of all vulnerable positions is obtained; y ismA gap state factor value for each position; m is the number of the position which is easy to damage; n is the number of vulnerable positions.
Claims (6)
1. A port machine damage positioning method based on a residual stress gap state is characterized by comprising the following steps: the method comprises the following steps:
s1, determining the position of the port machine structure which is vulnerable to damage;
s2, determining a real-time maximum residual stress interval value of a vulnerable position of the port machine;
s3, calculating a state value of the real-time residual stress gap of the port machine;
s4, determining a clearance state factor of each vulnerable position;
and S5, locating the port machine damage based on the residual stress gap state.
2. The port machine damage positioning method based on the residual stress gap state of claim 1, wherein: the determination method of step S1 includes: the method comprises the steps of importing a finite element analysis model of the whole port machine into finite element analysis software, carrying out gridding division on the finite element analysis model, setting constraint conditions and applying load conditions on the finite element analysis model according to actual working conditions of the port machine, carrying out post-processing on the finite element analysis model of the port machine, determining each vulnerable position of the port machine structure under the actual working conditions, and marking the model according to an analysis result, wherein the marking position is m, m is 1, 2 and 3.
3. The port machine damage positioning method based on the residual stress gap state as claimed in claim 2, characterized in that: the determination method of step S2 includes: combining the vulnerable positions of the port machine structure under the multiple actual working condition conditions determined in the 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 residual stress value sigma corresponding to each second in the ith minute according to the time interval of 1 minutemtMeasuring, and calculating an equivalent interval value q of the structure residual stress value at the m position at the ith minuteimAnd i represents a mark of the minute,
wherein ,qimThe equivalent interval value of the structural residual stress of the m-number damage position in the ith minute is shown; c (sigma)mt)maxThe maximum value of all residual stress values measured in every minute at the mth vulnerable position; c (sigma)mt)minThe minimum value of all residual stress values measured in every minute at the mth vulnerable position;
the average value of all residual stress values measured in every minute at the mth vulnerable position; t is a mark of seconds per minute,
real-time q-pair under actual working conditionimAnd calculating and recording.
4. The port machine damage positioning method based on the residual stress gap state of claim 3, characterized in that: the calculation method of step S3 is: combining the residual stress equivalent interval values q of each damage position calculated in S2imMaximum value of C (q) over monitoring time for each lesion siteim)maxWith a minimum value of C (q)im)minIdentify and record each lesion location as corresponding to C (q)im)maxAt a time point of C (t)m)maxAnd corresponds to C (q)im)minAt a time point of C (t)m)minAnd further calculating the residual stress gap state value J of each vulnerable position on the basism，
wherein ,tmTotal monitoring time for each injury site; q. q.simThe equivalent interval value of the residual stress of each damage position is obtained; j. the design is a squaremA residual stress gap state value for each vulnerable site; the compound gap homogenization coefficient; gamma is a singularization coefficient of the damage position; c (q)im)maxThe maximum value of the residual stress equivalent interval value of each damage position in the monitoring time is obtained; c (q)im)minThe minimum value of the residual stress equivalent interval value of each damage position in the monitoring time is obtained,
5. the port machine damage positioning method based on the residual stress gap state as claimed in claim 4, wherein: the method determined in S4 is: on the basis of the port machine real-time residual stress gap state value calculated in S3, the residual stress gap state value J corresponding to each vulnerable position is calculatedmSubstituting the following equation into the value of the gap state factor Y for each positionmThe calculation is carried out in such a way that,
wherein ,YmA gap state factor value for each position; j. the design is a squaremA residual stress gap state value for each vulnerable site; c (J)m)maxThe maximum value of the residual stress gap state value of each vulnerable position; c (J)m)minThe minimum value of the residual stress gap state value of each vulnerable position; γ is a singularization coefficient of the damage location.
6. The port machine damage positioning method based on the residual stress gap state of claim 5, wherein: the method for positioning in S5 is: on the basis of S4, all gap state factor values Y are extractedmZhongchao (middle surpass)
The position of (1), namely the position where the potential damage in the port machine has occurred,
wherein ,
the average value of the gap state factor values of all vulnerable positions is obtained; y ismA gap state factor value for each position; m is the number of the position which is easy to damage; n is the number of vulnerable positions.
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