CN116776616A - Method, system and equipment for determining physical life of secondary utilization steel wire rope - Google Patents

Method, system and equipment for determining physical life of secondary utilization steel wire rope Download PDF

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Publication number
CN116776616A
CN116776616A CN202310787840.6A CN202310787840A CN116776616A CN 116776616 A CN116776616 A CN 116776616A CN 202310787840 A CN202310787840 A CN 202310787840A CN 116776616 A CN116776616 A CN 116776616A
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steel wire
wire rope
determining
coefficient
rate
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刘健斌
谭智毅
李涵
莫蔓
陈明
余建龙
樊志维
李俊杰
颜焯文
沈文洁
梁美琼
徐薇
毛容妹
徐金梅
刘志文
林琦渲
肖前
萧达辉
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Guangzhou Customs Technology Center
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Guangzhou Customs Technology Center
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Abstract

The invention discloses a method, a system and equipment for determining the physical life of a secondary utilization steel wire rope, and relates to the technical field of steel wire rope life assessment. The method comprises the steps of taking the effective rate of a plurality of selectable steel wire ropes as independent variables, and taking the total utility relative change rate of the plurality of selectable steel wire ropes as dependent variables to perform linear fitting to obtain an effective rate-total utility relative change rate relation model; constructing a Hamilton function based on an optional effective rate-total utility relative change rate relation model and solving the Hamilton function to obtain a life determining model; and inputting the service time of the steel wire rope to be tested into an optional life determining model to obtain the residual effective performance utility value of the steel wire rope to be tested. According to the invention, the life evaluation of the steel wire rope before secondary utilization can be performed by constructing and solving the Hamilton function.

Description

Method, system and equipment for determining physical life of secondary utilization steel wire rope
Technical Field
The invention relates to the technical field of steel wire rope service life assessment, in particular to a method, a system and equipment for determining the physical service life of a secondary utilization steel wire rope.
Background
The steel wire rope is steel with higher technical content and higher material requirement, the recycling market of the existing steel wire rope is quite huge, and the physical life assessment of the secondarily utilized steel wire rope is a key technology of the existing steel wire rope recycling.
The life of a metal material is usually evaluated by means of scientific tests of physical life, which involve fatigue life and fatigue limit problems, which are stress levels for a new steel wire rope, i.e. through N 0 The sub-cycle life does not fail, and is roughly determined as follows: applying about sigma to a first specimen 1 Maximum stress of =0.7σb, via N 1 Failure of the secondary cycle; if N 1 <N 0 Continuing to apply about σ to the second sample 2 Stress of =0.45 σb, via N 2 Failure of the secondary cycle; if N 2 <N 0 The stress is continuously reduced until the sigma 2 Under the action of N 2 >N 0 Determining the fatigue limit sigma-1 at sigma 1 Sum sigma 2 Between them. At sigma 1 Sum sigma 2 Between 4 to 5 equidifferential stress levels are interposed, at 4 equidifferential stress levels (sigma 3 、σ 4 、σ 5 Sum sigma 6 ) For example, the experiment is performed step by step to obtain N corresponding lifetimes 3 、N 4 、N 5 And N 6 The method comprises the steps of carrying out a first treatment on the surface of the (1) If N 6 < N0, taking sigma 7 =(σ 26 ) And/2 again. If N 7 <N 0 And sigma (sigma) 72 Less than the control accuracy Δσ (typically 5% of the conditional fatigue limit), i.e. σ 72 < [ delta ] sigma, the fatigue limit sigma-1= (sigma) 72 ) 2; if N 7 >N 0 And sigma (sigma) 67 < [ delta ] sigma, the fatigue limit sigma-1= (sigma) 76 )/2. (2) If N 6 >N 0 Then use sigma 6 Sum sigma 5 Sigma of substitution (1) 2 Sum sigma 6 The method of (1) is repeated. The service lives N corresponding to the steel wire ropes after different stresses sigma are applied can be obtained through the method, the N is taken as an ordinate, the sigma is taken as an abscissa, and the service lives of the steel wire ropes can be determined by drawing an S-N curve.However, the fatigue test has high cost and long test time, and the estimated life result is not the direct life but the cycle number of the applied stress, and the physical life of the secondarily utilized steel wire rope is influenced by factors such as appearance, corrosion, use condition and the like, which are far from the ideal state that the method only applies the stress. Therefore, the method cannot be directly applied to the field of life assessment of the steel wire rope after secondary recovery.
Disclosure of Invention
The invention aims to provide a method, a system and equipment for determining the physical life of a secondary utilization steel wire rope, which can evaluate the life of the steel wire rope before secondary utilization.
In order to achieve the above object, the present invention provides the following solutions:
a physical life determining method for a secondary use steel wire rope comprises the following steps:
obtaining a plurality of steel wire ropes with the same specification; the service time of the plurality of steel wire ropes is different;
determining the loss rate of each steel wire rope;
according to the loss rate, determining the effective rate of the steel wire rope;
determining the total utility relative change rate of each steel wire rope;
taking the effective rates of the steel wire ropes as independent variables, and taking the total utility relative change rate of the steel wire ropes as the dependent variables to perform linear fitting to obtain an effective rate-total utility relative change rate relation model;
constructing a Hamilton function based on the relation model of the effective efficiency and the total effective utility relative change rate, and solving the Hamilton function by utilizing the relation between the residual effective performance utility value and the loss rate of the steel wire rope to obtain a life determining model; the independent variable of the life determining module is the service time; the dependent variable of the life determining module is a residual effective performance utility value;
and inputting the service time of the steel wire rope to be tested into the service life determining model to obtain the residual effective performance utility value of the steel wire rope to be tested.
Optionally, the sum of the loss rate and the effective rate is 1.
Optionally, the specification of the steel wire rope to be tested is the same as the specifications of the plurality of steel wire ropes for constructing the life determining model.
Optionally, the determining the loss rate of each steel wire rope includes:
determining any one of the steel wire ropes as a current steel wire rope;
determining the ratio of the number of broken monofilaments to the total number of monofilaments of the current steel wire rope as the broken wire loss rate of the current steel wire rope;
acquiring the diameter of the current steel wire rope before service as a nominal diameter;
acquiring the diameter of the current steel wire rope after service as the actual diameter;
determining the ratio of the difference value of the nominal diameter and the actual diameter of the current steel wire rope to the nominal diameter as the diameter reduction rate of the current steel wire rope;
acquiring the weight of a unit length of the current steel wire rope before service as a nominal weight;
acquiring the weight of the unit length of the current steel wire rope after service as the actual weight;
determining the ratio of the difference value of the nominal weight and the actual weight of the current steel wire rope to the nominal weight as the weight change rate of the current steel wire rope;
determining the deformation rate of the current steel wire according to the corrosion condition of the current steel wire;
acquiring the internal performance utility loss rate of the current steel wire;
and determining the loss rate of the current steel wire rope according to the loss rate of broken wires, the diameter reduction rate, the weight change rate, the deformation rate and the internal performance utility loss rate of the current steel wire rope.
Optionally, the loss rate is:
V(t)=λ breaking of the wire (1-V Breaking of the wire (t))×λ Shrinking process (1-V Shrinking process (t))×λ Heavy weight (1-V Heavy weight (t))×λ Shape of a Chinese character (1-V Shape of a Chinese character (t))×λ Inner part (1-V Inner part (t));
Wherein V (t) is the loss rate; lambda (lambda) Breaking of the wire 、λ Shrinking process 、λ Heavy weight 、λ Shape of a Chinese character And lambda (lambda) Inner part Are all weights; v (V) Breaking of the wire (t) is the loss rate of broken wire; v (V) Shrinking process (t) is the diameter reduction rate; v (V) Heavy weight (t) a weight change rate; v (V) Shape of a Chinese character (t) is the deformation ratio; v (V) Inner part And (t) is the internal performance utility loss rate.
Optionally, the obtaining the internal performance utility loss rate of the current steel wire includes:
acquiring the performance conversion coefficient of the current steel wire;
acquiring the breaking force of the current steel wire before service as a nominal breaking force;
acquiring the breaking force of the current steel wire after service as the actual breaking force;
determining the ratio of the actual breaking force to the nominal breaking force as an overall breaking coefficient;
acquiring the key chemical component quantity before the service of the current steel wire as the nominal key chemical component quantity;
acquiring the key chemical component quantity of the current steel wire after service as the actual key chemical component quantity;
determining the ratio of the actual key chemical component amount to the nominal key chemical component amount as an overall chemical coefficient;
determining the overall comprehensive performance coefficient of the current steel wire according to the performance conversion coefficient, the overall rupture coefficient and the overall chemical coefficient;
acquiring the tensile strength of a monofilament in the current steel wire before service as the nominal tensile strength of the monofilament;
acquiring the tensile strength of the current steel wire after service as the actual tensile strength of the monofilament;
determining that the ratio of the actual monofilament tensile strength to the nominal monofilament tensile strength is a monofilament tensile strength coefficient;
acquiring the number of twist-off times before service of the monofilaments in the current steel wire as the nominal number of twist-off times of the monofilaments;
acquiring the number of twist-off times of the monofilaments in the current steel wire after service as the actual number of twist-off times of the monofilaments;
determining the ratio of the actual filament twist-off times to the nominal filament twist-off times as a filament twist-off times coefficient;
acquiring the bending times of the monofilaments in the current steel wire before service as nominal monofilament bending times;
acquiring the number of bending times of the monofilaments in the current steel wire after service as the actual number of bending times of the monofilaments;
determining the ratio of the actual number of filament bends to the nominal number of filament bends as a number of filament bends coefficient;
determining a monofilament comprehensive performance coefficient according to the performance conversion coefficient, the overall chemical coefficient, the monofilament tensile strength coefficient, the monofilament twist-off frequency coefficient and the monofilament bending frequency coefficient;
determining the average value of the overall comprehensive performance coefficient and the monofilament comprehensive performance coefficient as the comprehensive performance coefficient of the current steel wire;
and determining the internal performance utility loss rate of the current steel wire according to the comprehensive performance coefficient.
Alternatively to this, the method may comprise,
the overall comprehensive performance coefficient is as follows:
K finishing the whole =L×(K Breaking the +K Chemical treatment )/2;
Wherein K is Finishing the whole Is the integral comprehensive performance coefficient; l is a performance conversion coefficient; k (K) Breaking the Is the integral breaking coefficient; k (K) Chemical treatment Is the overall chemical coefficient;
the monofilament comprehensive performance coefficient is as follows:
K single sheet =L×(K Monoclonal antibody +K Single button +K Single bend +K Chemical treatment )/4;
Wherein K is Single sheet Internal performance utility loss rate monofilament composite coefficient of performance; k (K) Monoclonal antibody Is the tensile strength coefficient of the monofilament; k (K) Single button Is the coefficient of the number of times of filament twist-off; k (K) Single bend Is the coefficient of the number of times of bending the monofilament;
the internal performance utility loss rate is:
V inner (t) =1-K;
Wherein V is Inner (t) Utility loss rate for internal performance; k is the comprehensive performance coefficient.
A physical life determining system for a secondary usage of a steel cord, comprising:
the steel wire rope acquisition module is used for acquiring a plurality of steel wire ropes with the same specification; the service time of the plurality of steel wire ropes is different;
the loss rate determining module is used for determining the loss rate of each steel wire rope;
the effective rate determining module is used for determining the effective rate of the steel wire rope according to the loss rate;
the total utility relative change rate determining module is used for determining the total utility relative change rate of each steel wire rope;
the linear fitting module is used for carrying out linear fitting by taking the effective rates of the plurality of steel wire ropes as independent variables and taking the total utility relative change rate of the plurality of steel wire ropes as dependent variables to obtain an effective rate-total utility relative change rate relation model;
the life determining model construction module is used for constructing a Hamilton function based on the relation model of the effective rate and the total effective rate and solving the Hamilton function by utilizing the relation between the residual effective performance utility value and the loss rate of the steel wire rope to obtain a life determining model; the independent variable of the life determining module is the service time; the dependent variable of the life determining module is a residual effective performance utility value;
and the service life evaluation module is used for inputting the service time of the steel wire rope to be tested into the service life determination model to obtain the residual effective performance utility value of the steel wire rope to be tested.
An electronic device comprising a memory for storing a computer program and a processor that runs the computer program to cause the electronic device to perform the method.
Optionally, the memory is a readable storage medium.
According to the specific embodiment provided by the invention, the invention discloses the following technical effects:
according to the physical life determining method, system and equipment for the secondary utilization steel wire ropes, a plurality of steel wire ropes with the same specification are obtained, the effective rate of the plurality of steel wire ropes is taken as an independent variable, and the total utility relative change rate of the plurality of steel wire ropes is taken as a dependent variable to perform linear fitting, so that an effective rate-total utility relative change rate relation model is obtained; constructing a Hamilton function based on an effective efficiency-total effectiveness relative change rate relation model, and solving the Hamilton function by utilizing the residual effective performance effectiveness value-loss rate relation of the steel wire rope to obtain a life determining model; the independent variable of the life determining module is the service time; the dependent variable of the life determining module is the utility value of the residual effective performance; and inputting the service time of the steel wire rope to be tested into a life determining model to obtain the residual effective performance utility value of the steel wire rope to be tested. The service life of the steel wire rope before secondary utilization can be evaluated by constructing and solving the Hamilton function.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions of the prior art, the drawings that are needed in the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a flow chart of a method for determining physical life of a secondary usage wire rope in example 1 of the present invention;
FIG. 2 is a graph showing the relationship between effective rate and total effective rate of change in example 1 of the present invention;
FIG. 3 is a schematic diagram of a life determining model in example 1 of the present invention.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The invention aims to provide a method, a system and equipment for determining the physical life of a secondary utilization steel wire rope, which can evaluate the life of the steel wire rope before secondary utilization.
In order that the above-recited objects, features and advantages of the present invention will become more readily apparent, a more particular description of the invention will be rendered by reference to the appended drawings and appended detailed description.
Example 1
As shown in fig. 1, the present embodiment provides a physical lifetime determining method for a secondary usage of a steel wire rope, including:
step 101: obtaining a plurality of steel wire ropes with the same specification; the service time of the plurality of steel wire ropes is different.
Step 102: the loss rate of each wire rope is determined.
Step 103: and determining the effective rate of the steel wire rope according to the loss rate. The sum of the loss rate and the effective rate is 1.
Step 104: the total utility relative rate of change for each wire rope is determined.
Relative rate of change of total utility of wire rope for time tIn general, when loss occurs, the larger the loss rate V (t), the smaller the wire rope effective rate U (t), and the smaller the remaining effective performance utility value Y (t). Generally, when the initial loss is small and the loss rate V (t) is small, the relative change rate of the total utility of the steel wire rope at the time t increases with the increase of the loss rate V (t) (V (t) =1-U (t)), and when V (t) increases to a certain extent, the relative change rate of the total utility of the steel wire rope drops sharply and quickly becomes 0 or equal.
Step 105: and performing linear fitting by taking the effective rates of the plurality of steel wire ropes as independent variables and the total utility relative change rate of the plurality of steel wire ropes as dependent variables to obtain an effective rate-total utility relative change rate relation model.
Step 106: constructing a Hamilton function based on an effective efficiency-total effectiveness relative change rate relation model, and solving the Hamilton function by utilizing the residual effective performance effectiveness value-loss rate relation of the steel wire rope to obtain a life determining model; the independent variable of the life determining module is the service time; the dependent variable of the lifetime determination model is the remaining effective performance utility value.
Step 107: and inputting the service time of the steel wire rope to be tested into a life determining model to obtain the residual effective performance utility value of the steel wire rope to be tested. The specification of the steel wire rope to be tested is the same as that of a plurality of steel wire ropes for constructing a life determining model.
Step 102, including:
step 1021: and determining any one of the steel wire ropes as the current steel wire rope.
Step 1022: and determining the ratio of the number of broken monofilaments to the total number of monofilaments of the current steel wire rope as the broken wire loss rate of the current steel wire rope.
Step 1023: and obtaining the diameter of the current steel wire rope before service as a nominal diameter.
Step 1024: and obtaining the diameter of the current steel wire rope after service as the actual diameter.
Step 1025: and determining the ratio of the difference value of the nominal diameter and the actual diameter of the current steel wire rope to the nominal diameter as the diameter reduction rate of the current steel wire rope.
Step 1026: and obtaining the weight of the unit length of the current steel wire rope before service as the nominal weight.
Step 1027: and obtaining the weight of the unit length of the current steel wire rope after service as the actual weight.
Step 1028: and determining the ratio of the difference value of the nominal weight and the actual weight of the current steel wire rope to the nominal weight as the weight change rate of the current steel wire rope.
Step 1029: and determining the deformation rate of the current steel wire according to the corrosion condition of the current steel wire.
Step 10210: and obtaining the internal performance utility loss rate of the current steel wire.
Step 10211: and determining the loss rate of the current steel wire rope according to the loss rate of broken wires, the diameter reduction rate, the weight change rate, the deformation rate and the internal performance utility loss rate of the current steel wire rope.
Wherein, the loss rate is:
V(t)=λ breaking of the wire (1-V Breaking of the wire (t))×λ Shrinking process (1-V Shrinking process (t))×λ Heavy weight (1-V Heavy weight (t))×λ Shape of a Chinese character (1-V Shape of a Chinese character (t))×λ Inner part (1-V Inner part (t))。
Wherein V (t) is the loss rate; lambda (lambda) Breaking of the wire 、λ Shrinking process 、λ Heavy weight 、λ Shape of a Chinese character And lambda (lambda) Inner part Are all weights; v (V) Breaking of the wire (t) is the loss rate of broken wire; v (V) Shrinking process (t) is the diameter reduction rate; v (V) Heavy weight (t) a weight change rate; v (V) Shape of a Chinese character (t) is the deformation ratio; v (V) Inner part And (t) is the internal performance utility loss rate.
Step 10210, comprising:
step 10210-1: and obtaining the performance conversion coefficient of the current steel wire.
Step 10210-2: and obtaining the breaking force of the current steel wire before service as a nominal breaking force.
Step 10210-3: and obtaining the breaking force of the current steel wire after service as the actual breaking force.
Step 10210-4: and determining the ratio of the actual breaking force to the nominal breaking force as an integral breaking coefficient.
Step 10210-5: and acquiring the key chemical component quantity before the service of the current steel wire as the nominal key chemical component quantity.
Step 10210-6: and acquiring the key chemical component quantity of the current steel wire after service as the actual key chemical component quantity.
Step 10210-7: the ratio of the actual key chemical component amount to the nominal key chemical component amount is determined as the overall chemical coefficient.
Step 10210-8: and determining the overall comprehensive performance coefficient of the current steel wire according to the performance conversion coefficient, the overall rupture coefficient and the overall chemical coefficient.
The overall comprehensive performance coefficient is as follows:
K finishing the whole =L×(K Breaking the +K Chemical treatment )/2;
Wherein K is Finishing the whole Is the integral comprehensive performance coefficient; l is a performance conversion coefficient; k (K) Breaking the Is the integral breaking coefficient; k (K) Chemical treatment Is the overall chemical coefficient.
Step 10210-9: and obtaining the tensile strength of the monofilament in the current steel wire before service as the nominal tensile strength of the monofilament.
Step 10210-10: and obtaining the tensile strength of the current filaments in the steel wire after service as the actual tensile strength of the filaments.
Step 10210-11: the ratio of the actual monofilament tensile strength to the nominal monofilament tensile strength is determined as the monofilament tensile strength coefficient.
Step 10210-12: and obtaining the number of twist-off times before service of the monofilaments in the current steel wire as the nominal number of twist-off times of the monofilaments.
Step 10210-13: and obtaining the number of twist-off times of the monofilaments in the current steel wire after service as the actual number of twist-off times of the monofilaments.
Step 10210-14: and determining the ratio of the actual filament twist-off times to the nominal filament twist-off times as a filament twist-off times coefficient.
Step 10210-15: and obtaining the bending times before service of the monofilaments in the current steel wire as nominal monofilament bending times.
Step 10210-16: and obtaining the number of bending times of the current filaments in the steel wire after service as the actual number of bending times of the filaments.
Step 10210-17: the ratio of the actual number of filament bends to the nominal number of filament bends is determined as the coefficient of filament bends.
Step 10210-18: determining the comprehensive performance coefficient of the monofilament according to the performance conversion coefficient, the overall chemical coefficient, the tensile strength coefficient of the monofilament, the twist-off frequency coefficient of the monofilament and the bending frequency coefficient of the monofilament; the monofilament comprehensive performance coefficient is as follows:
K single sheet =L×(K Monoclonal antibody +K Single button +K Single bend +K Chemical treatment )/4;
Wherein K is Single sheet Internal performance utility loss rate monofilament composite coefficient of performance; k (K) Monoclonal antibody Is the tensile strength coefficient of the monofilament; k (K) Single button Is the coefficient of the number of times of filament twist-off; k (K) Single bend Is the coefficient of the number of times the monofilament bends.
Steps 10210-19: and determining the average value of the overall comprehensive performance coefficient and the monofilament comprehensive performance coefficient as the comprehensive performance coefficient of the current steel wire.
Step 10210-20: and determining the internal performance utility loss rate of the current steel wire according to the comprehensive performance coefficient.
Wherein, the internal performance utility loss rate is:
V inner (t) =1-K;
Wherein V is Inner (t) Utility loss rate for internal performance; k is the comprehensive performance coefficient.
Example 2
The embodiment provides a physical life determining method for a secondary utilization steel wire rope, which comprises the following steps:
STEP1 defines the performance utility value Y of the steel cord: the performance utility value represents the load capacity (including tensile, yield, bending, winding, fatigue, etc.) generated by the steel wire rope under the action of external force, or the capacity of the steel wire rope. The utility value of the secondary utilization wire rope performance reflects that under the conditions of the same raw material type, the same or equivalent quality level and the same weight unit, the secondary utilization material is directly put into use or regenerated (processed for reprocessing or mixing new material), so that the ratio of the difference between the service life of the new product produced by the performance change and the service life of the new product produced by the new material is the utility ratio of the secondary utilization wire rope performance, namely the utility ratio for short.
STEP2 definition of the value Y of the intrinsic Property of the wire rope to be secondarily utilized Inner part . Value Y of inherent property of steel wire rope Inner part Refers specifically to the physical properties (including chemical composition changes) within the steel cord. This inherent performance value of the new and old steel wire ropes is simply referred to as a performance value. The performance utility value needs to consider the influence of external deformation such as wire breakage and corrosion in addition to the intrinsic performance value of the inside.
STEP3 establishes an intrinsic Performance value Y Inner part Mathematical model:
intrinsic property value Y Inner part : according to GB 8918, intrinsic Performance value Y Inner part Including mechanical properties and chemical composition, the following detection items can be considered, generally for steel wire ropes:
the following data for the whole steel cord were measured: breaking load S of whole rope before and after service New breaking And S is Old fracture The method comprises the steps of carrying out a first treatment on the surface of the Critical chemical component H before and after service New type And H Old one The method comprises the steps of carrying out a first treatment on the surface of the Tensile strength F of monofilament before and after service Shan Xin And F Single old The method comprises the steps of carrying out a first treatment on the surface of the Number of filament twists Nz before and after service Shan Xin And Nz Single old And the number of times of repeated bending of the monofilament W Shan Xin And W is Single old And under a certain specification eachAnd the performance conversion coefficient L of the test item can be used for determining the range or specific numerical value according to a plurality of experiments and steel wire rope data tables with different specifications of standard edition.
Obtaining the overall comprehensive performance coefficient K Finishing the whole And the internal coefficient of performance K of the monofilament Single sheet
K Breaking the =S Old fracture /S New breaking
K Chemical treatment =H Old one /H New type
K Finishing the whole =L×(K Breaking the +K Chemical treatment )/2。
K Monoclonal antibody =F Single old /F Shan Xin
K Single button =Nz Single old /Nz Shan Xin
K Single bend =W Single old /W Shan Xin
K Single sheet =L×(K Monoclonal antibody +K Single button +K Single bend +K Chemical treatment )/4。
For example: the tension break of the new rope can be approximately calculated as follows: s is S New breaking =500d 2
Working tension S of new rope approximate limit New ultimate tensile force =S New breaking /h=500d 2
Wherein d is the diameter of the steel wire rope; h is the safety coefficient of the steel wire rope, and the safety coefficients of the steel wire ropes for different purposes are different and are given by the standard.
If K Single sheet Since objective condition limitation is not good and can be calculated by testing the performance of the old rope (the steel wire rope is difficult to split), the safety coefficient h and the reduction coefficient J of the national standard can be calculated approximately, and the method is as follows: k (K) Single sheet =J/h。
Coefficient of comprehensive performance k= (K) Finishing the whole +K Single sheet ) Either/2 is covariance. K is the effective rate used later, and 1-K is the loss rate later.
Calculating the physical property value of the STEP4 single (wire-dismantling) steel wire rope:
first case:
if the old steel wire rope is directly reused and is not subjected to regeneration treatment, the performance value of the old steel wire rope is kept or reduced. And (5) measuring the sum of the breaking force of the steel wires in the steel wire rope according to GB 8358 (or GB 20118).
Tensile test was performed on a single steel wire: obtaining F by calculating residual load capacity Old one Splitting the steel wire rope, and independently measuring physical properties of each wire, wherein the loading capacity of the single wire is F Single sheet When all the steel wires in the steel wire rope are tested, the actually measured breaking force of each steel wire is added.
F Old general =N 1 F Single 1 +N 2 F Single 2 +···N n F Single n
Wherein N is 1 ,N 2 ,....N n All represent the total number of monofilaments of the same specification of steel wire rope.
F when testing the inner wire of the wire rope Total (S) =F 0 +F 1 N 11 +F 2 N 21 +F 3 N 31 +…+F n N n1
Wherein F is Total (S) The sum of the breaking force of the steel wire; f (F) 1 、F 2 、F 3 ...F n The sum of the actually measured breaking force of the steel wires in the strands with the same structure and the same diameter and the calculated breaking force of the steel wires which do not participate in the test is adopted; f (F) 0 Calculating breaking force for a steel core in the steel wire rope, namely determining the sum of the breaking force calculated by multiplying the diameter area of the steel wire before twisting by the nominal tensile strength of the steel wire; n (N) 11 、N 21 、N 31 …N n1 Is the number of strands with the same structure and diameter in the steel wire rope.
In the second case, the wire rope recovery plant is used for machining or production and reprocessing to a certain extent, but the use of the wire rope is not changed, F Old one =NF Single sheet
Calculating actual measured breaking force:
dividing the sum of measured steel wire breaking force by the coefficient in the table (the coefficient in the table can be inquired in GB/T20118-2017 annex A), wherein the measured breaking force of the steel wire rope=steel wire breaking forceForce sum/coefficient, namely: f (F) Real world =F Total (S) /e。
Wherein F is Real world Is the actually measured breaking force; f (F) Total (S) The sum of the breaking force of the steel wire; and e is the calculation of the breaking force coefficient. Examples: the coefficient of the 6X7 fiber core steel wire rope with the nominal diameter of 10 is 1.134, the sum of the steel wire breaking force is 60, and then the sum of the steel wire breaking force F Real world =60/1.134=52.9kN。
And (5) constructing a Setp5 effective rate-total utility relative change rate relation model.
Coefficient of comprehensive performance K Single sheet Is calculated by K Monoclonal antibody Obtaining; the calculation of the coefficient of performance K is performed by K= (K) Finishing the whole +K Monoclonal antibody ) And/2, or using a covariance method. The performance utility value is relatively complex to calculate and is determined by the appearance surface, corrosion form, weight, diameter, internal physical properties and other factors.
The service life of the steel wire rope can be estimated correctly according to the actual use environment and stress condition, and the service life is naturally different by pulling 100 tons and using under different environments or 500 tons. The life prediction is actually based on a relationship between the performance of the wire rope and the load and time under the condition of approximately the same environment and approximately the stress. For the secondary used steel wire rope, the internal abrasion is increased along with the increase of the relative displacement of the steel wires, and the contact stress between every two strands is larger and larger when the bending stress is larger, so that the abrasion of the adjacent steel wires is larger and larger, the loss of the steel wire rope is more obvious, and important consideration is needed. A wire rope, if the ultimate tensile load is 100 tons, is subjected to a tensile force S of 50 tons at time T, and its remaining capacity cannot be equal to 100-50 tons at this time. While the capacity Z consumed is a function of S, the greater the tension S, the greater the consumption Z. The consumption capability can be calculated by S; the remaining capacity can be retested for the limit load it can currently withstand; if the pulling force is 50 tons broken, this indicates zero remaining capacity. However, under the condition that the steel wire rope is used for a long time (such as one year) and is stressed for a long time, the steel wire rope is likely to harden, and the residual load can break through 100 tons, so that the service life of the steel wire rope is estimated, and a new concept must be introduced besides the external factors such as the same stress condition: performance utility value.
The total performance utility of the steel wire rope can be divided into two parts, namely, the effective performance (or the capability owned at present and also called residual capability) is ensured, and the exerted performance is a performance utility value E; the other part is used for breaking, i.e. loss value.
If the effective performance value (remaining capacity) is zero, it is indicated that the wire rope has lost its function and the life is up to the end. Thus, the total utility and total loss values of the steel wire rope, which define the state function X (t) to represent the time t, can be set. Definition Y (t) represents the effective performance utility value of the wire rope remainder at time t. Defining a utility value of the loss performance of the steel wire rope at the moment of t, wherein Z (t) is defined as follows: x (t) =y (t) +z (t). Let the control function U (t) =y (t)/X (t) denote the wire rope effective rate at time t, then there are: loss ratio V (t) =1-U (t).
Furthermore, internal performance utility loss ratio V Inner part (t)=1-K。
The loss rate can be tested in several ways.
5.1 Loss rate of broken wire):
wherein V is Breaking of the wire And (t) is the loss rate of broken wire of the sample steel wire rope, and the unit is: the%; n is the number of broken wires of the sample steel wire rope, and the unit is: root; s is the total number of the steel wire ropes of the sample, and the unit is: root.
5.2 Diameter reduction rate):
wherein V is Shrinking process And (t) is the reduction rate of the diameter of the steel wire rope of the sample, and the unit is: the%; r is R Nominal of (1) Nominal diameter of sample wire rope, unit: mm; r is R Actual measurement The actual diameter measured for the sample wire rope in standard methods, units: mm.
5.3 Rate of change of weight):
wherein V is Heavy weight And (t) is the weight change rate of the sample steel wire rope, and the unit is: the%; m is M Nominal of (1) The unit is the nominal weight of the unit length of the sample steel wire rope: kg/100m; m is M Actual measurement The measured weight of the unit length of the sample steel wire rope is as follows: kg/100m.
5.4 Deformation ratio V in external corrosion and the like Shape of a Chinese character (t)
According to the actual situation estimation proportion, an estimation rule is illustrated:
5.4.1 The number of broken wires of the hoisting machinery steel wire rope in one twisting pitch is 10% of the total number of wires of the steel wire rope. If the rope is 6×19=114 filaments, the rope should be scrapped when the number of broken filaments reaches 12 filaments.
5.4.2 If the rope is 6×37=222 filaments, the renewal should be scrapped when the number of broken filaments reaches 22 filaments. For a steel wire rope composed of thick and thin wires, the number of broken wires is calculated by one wire, and the number of thick wires is calculated by 1.7 wires.
5.4.3 The radial abrasion or corrosion amount of the steel wire exceeds 40% of the original diameter and can be scrapped according to the specified number of broken wires when the radial abrasion or corrosion amount of the steel wire is less than 40%. The number of scrapped wires of the steel wire rope for lifting the hot metal or dangerous goods by the lifting machinery is half of the scrapped standard of the steel wire rope for a common crane.
5.4.4 If serious internal corrosion is confirmed, the steel wire rope should be scrapped immediately, namely V Shape of a Chinese character (t)=0。
5.5 Internal performance utility loss rate: v (V) Inner part (t)=1-K。
And further determining the internal remaining physical capacity of the steel wire rope:
V(t)=λ breaking of the wire (1-V Breaking of the wire (t))×λ Shrinking process (1-V Shrinking process (t))×λ Heavy weight (1-V Heavy weight (t))×λ Shape of a Chinese character (1-V Shape of a Chinese character (t))×λ Inner part (1-V Inner part (t))
X (t)/X (t) is the relative rate of change of the total utility of the steel wire rope at the moment. In general, when loss occurs, the larger the loss rate V (t), the smaller the wire rope effective rate U (t), and the smaller the remaining effective performance utility value Y (t). Generally, when the initial loss is small and the loss rate V (t) is small, the relative change rate of the total utility of the steel wire rope at the time t increases with the increase of V (t) (V (t) =1-U (t)), and when V (t) increases to a certain extent, the relative change rate of the total utility of the steel wire rope drops sharply and quickly becomes 0 or more.
As in fig. 2, a descriptive relationship model is built:
x' (t) represents the first derivative of X (t) with respect to t,
the method is characterized by comprising the following steps: x'/x=au 3 -bu 2 +cu+d。
Wherein a, b and c are coefficients.
In fig. 2, dx/x is the relative change rate of the total utility of the wire rope at time t, and U (t) is the control function (wire rope effective rate at time t).
STEP6 construction of life determining model
The lifetime assessment problem becomes thus a maximum loss rate U (t) (which in certain conditions can be understood as limit load), under the conditions (x/x=au 3 -bu 2 +cu+d) minimizes T, i.e. the service life of the wire rope. T is a mutual change relation function between the total utility relative change rate of the steel wire rope at the moment T and the effective rate of the steel wire rope at the moment T.
Expressed by the formula:
x=(au 3 -bu 2 +cu+d)x。
X(0)=x 0 ,X(T)=x T
constructing Hamilton function
H=1+β(au 3 -bu 2 +cu+d)x。
Due to
So that
(1)
(2)3aβxu 2 -2bβxu+cβx=0。
(3)=(au 3 -bu 2 +cu+d)x。
From this three equations:is a constant.
Let p=au 3 -bu 2 +cu+d。
Then there isdy/dx=-py,dy/y=-pd x。
The two sides take the integral, then there are:
Lny=-px。
Y=e -px
β=e -p(t) let y=x (t), dy/dt= -py, dy/y= -pdt.
Two-side integration to obtain general solution:
Lny=-pt+G。
one solution is:
X(t)=Ge -pt
from X (0) =x, X (T) =x T, X (t) =Y (t)/U, to obtain
Y(t)=U·Ge -pt
The resulting life determination model is shown in fig. 3, where X (t) represents the total performance utility and total loss value of the wire rope at time t. Definition Y (t) indicates the availability of wire rope residuals at time tEnergy utility value. Performance index in the J poincare Jin Jizhi principle,is a boundary condition; a represents U (t) 3 B represents U (t) 2 C represents the weighting factor of U (t), a, b, c, d is a positive constant integer to reflect the correspondence between the relative growth rate and the effective rate of the total performance utility value. H represents the Hamilton function, β represents the coupling function in the Pang Deli sub Jin Jizhi principle; />Representing the first derivative result beta' represents the derivative of beta.
Example 3
In order to perform the method corresponding to embodiment 1 or embodiment 2 described above to achieve the corresponding functions and technical effects, a physical lifetime determination system for a secondary usage wire rope is provided below, comprising:
the steel wire rope acquisition module is used for acquiring a plurality of steel wire ropes with the same specification; the service time of the plurality of steel wire ropes is different.
And the loss rate determining module is used for determining the loss rate of each steel wire rope.
And the effective rate determining module is used for determining the effective rate of the steel wire rope according to the loss rate.
The total utility relative change rate determining module is used for determining the total utility relative change rate of each steel wire rope.
And the linear fitting module is used for carrying out linear fitting by taking the effective rate of the plurality of steel wire ropes as independent variables and the total utility relative change rate of the plurality of steel wire ropes as dependent variables to obtain an effective rate-total utility relative change rate relation model.
The life determining model construction module is used for constructing a Hamilton function based on the relation model of the effective rate and the total effective rate and solving the Hamilton function by utilizing the relation of the residual effective performance utility value and the loss rate of the steel wire rope to obtain a life determining model; the independent variable of the life determining module is the service time; the dependent variable of the lifetime determination model is the remaining effective performance utility value.
The service life evaluation module is used for inputting the service time of the steel wire rope to be tested into the service life determination model to obtain the residual effective performance utility value of the steel wire rope to be tested.
Example 4
The present embodiment provides an electronic device including a memory for storing a computer program and a processor that runs the computer program to cause the electronic device to perform the method described in embodiment 1 or embodiment 2. Wherein the memory is a readable storage medium.
In the present specification, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different point from other embodiments, and identical and similar parts between the embodiments are all enough to refer to each other. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant points refer to the description of the method section.
The principles and embodiments of the present invention have been described herein with reference to specific examples, the description of which is intended only to assist in understanding the methods of the present invention and the core ideas thereof; also, it is within the scope of the present invention to be modified by those of ordinary skill in the art in light of the present teachings. In view of the foregoing, this description should not be construed as limiting the invention.

Claims (10)

1. The method for determining the physical life of the secondary utilization steel wire rope is characterized by comprising the following steps of:
obtaining a plurality of steel wire ropes with the same specification; the service time of the plurality of steel wire ropes is different;
determining the loss rate of each steel wire rope;
according to the loss rate, determining the effective rate of the steel wire rope;
determining the total utility relative change rate of each steel wire rope;
taking the effective rates of the steel wire ropes as independent variables, and taking the total utility relative change rate of the steel wire ropes as the dependent variables to perform linear fitting to obtain an effective rate-total utility relative change rate relation model;
constructing a Hamilton function based on the relation model of the effective efficiency and the total effective utility relative change rate, and solving the Hamilton function by utilizing the relation between the residual effective performance utility value and the loss rate of the steel wire rope to obtain a life determining model; the independent variable of the life determining module is the service time; the dependent variable of the life determining module is a residual effective performance utility value;
and inputting the service time of the steel wire rope to be tested into the service life determining model to obtain the residual effective performance utility value of the steel wire rope to be tested.
2. A method of determining the physical life of a secondary usage wire rope according to claim 1, wherein the sum of the loss rate and the effective rate is 1.
3. The method for determining the physical life of a secondary usage wire rope according to claim 1, wherein the wire rope to be tested has the same specification as the plurality of wire ropes constituting the life determining model.
4. A method of determining the physical life of a secondary usage wire rope according to claim 1, wherein said determining the loss rate of each wire rope comprises:
determining any one of the steel wire ropes as a current steel wire rope;
determining the ratio of the number of broken monofilaments to the total number of monofilaments of the current steel wire rope as the broken wire loss rate of the current steel wire rope;
acquiring the diameter of the current steel wire rope before service as a nominal diameter;
acquiring the diameter of the current steel wire rope after service as the actual diameter;
determining the ratio of the difference value of the nominal diameter and the actual diameter of the current steel wire rope to the nominal diameter as the diameter reduction rate of the current steel wire rope;
acquiring the weight of a unit length of the current steel wire rope before service as a nominal weight;
acquiring the weight of the unit length of the current steel wire rope after service as the actual weight;
determining the ratio of the difference value of the nominal weight and the actual weight of the current steel wire rope to the nominal weight as the weight change rate of the current steel wire rope;
determining the deformation rate of the current steel wire according to the corrosion condition of the current steel wire;
acquiring the internal performance utility loss rate of the current steel wire;
and determining the loss rate of the current steel wire rope according to the loss rate of broken wires, the diameter reduction rate, the weight change rate, the deformation rate and the internal performance utility loss rate of the current steel wire rope.
5. The method for determining the physical life of a secondary usage wire rope according to claim 4, wherein the loss rate is:
V(t)=λ breaking of the wire (1-V Breaking of the wire (t))×λ Shrinking process (1-V Shrinking process (t))×λ Heavy weight (1-V Heavy weight (t))×λ Shape of a Chinese character (1-V Shape of a Chinese character (t))×λ Inner part (1-V Inner part (t));
Wherein V (t) is the loss rate; lambda (lambda) Breaking of the wire 、λ Shrinking process 、λ Heavy weight 、λ Shape of a Chinese character And lambda (lambda) Inner part Are all weights; v (V) Breaking of the wire (t) is the loss rate of broken wire; v (V) Shrinking process (t) is the diameter reduction rate; v (V) Heavy weight (t) a weight change rate; v (V) Shape of a Chinese character (t) is the deformation ratio; v (V) Inner part And (t) is the internal performance utility loss rate.
6. The method for determining the physical life of a secondary usage wire rope according to claim 4, wherein the obtaining the internal performance utility loss rate of the current wire comprises:
acquiring the performance conversion coefficient of the current steel wire;
acquiring the breaking force of the current steel wire before service as a nominal breaking force;
acquiring the breaking force of the current steel wire after service as the actual breaking force;
determining the ratio of the actual breaking force to the nominal breaking force as an overall breaking coefficient;
acquiring the key chemical component quantity before the service of the current steel wire as the nominal key chemical component quantity;
acquiring the key chemical component quantity of the current steel wire after service as the actual key chemical component quantity;
determining the ratio of the actual key chemical component amount to the nominal key chemical component amount as an overall chemical coefficient;
determining the overall comprehensive performance coefficient of the current steel wire according to the performance conversion coefficient, the overall rupture coefficient and the overall chemical coefficient;
acquiring the tensile strength of a monofilament in the current steel wire before service as the nominal tensile strength of the monofilament;
acquiring the tensile strength of the current steel wire after service as the actual tensile strength of the monofilament;
determining that the ratio of the actual monofilament tensile strength to the nominal monofilament tensile strength is a monofilament tensile strength coefficient;
acquiring the number of twist-off times before service of the monofilaments in the current steel wire as the nominal number of twist-off times of the monofilaments;
acquiring the number of twist-off times of the monofilaments in the current steel wire after service as the actual number of twist-off times of the monofilaments;
determining the ratio of the actual filament twist-off times to the nominal filament twist-off times as a filament twist-off times coefficient;
acquiring the bending times of the monofilaments in the current steel wire before service as nominal monofilament bending times;
acquiring the number of bending times of the monofilaments in the current steel wire after service as the actual number of bending times of the monofilaments;
determining the ratio of the actual number of filament bends to the nominal number of filament bends as a number of filament bends coefficient;
determining a monofilament comprehensive performance coefficient according to the performance conversion coefficient, the overall chemical coefficient, the monofilament tensile strength coefficient, the monofilament twist-off frequency coefficient and the monofilament bending frequency coefficient;
determining the average value of the overall comprehensive performance coefficient and the monofilament comprehensive performance coefficient as the comprehensive performance coefficient of the current steel wire;
and determining the internal performance utility loss rate of the current steel wire according to the comprehensive performance coefficient.
7. The method for determining the physical life of a secondary usage wire rope according to claim 6,
the overall comprehensive performance coefficient is as follows:
K finishing the whole =L×(K Breaking the +K Chemical treatment )/2;
Wherein K is Finishing the whole Is the integral comprehensive performance coefficient; l is a performance conversion coefficient; k (K) Breaking the Is the integral breaking coefficient; k (K) Chemical treatment Is the overall chemical coefficient;
the monofilament comprehensive performance coefficient is as follows:
K single sheet =L×(K Monoclonal antibody +K Single button +K Single bend +K Chemical treatment )/4;
Wherein K is Single sheet Internal performance utility loss rate monofilament composite coefficient of performance; k (K) Monoclonal antibody Is the tensile strength coefficient of the monofilament; k (K) Single button Is the coefficient of the number of times of filament twist-off; k (K) Single bend Is the coefficient of the number of times of bending the monofilament;
the internal performance utility loss rate is:
V inner (t) =1-K;
Wherein V is Inner (t) Utility loss rate for internal performance; k is the comprehensive performance coefficient.
8. A physical life determining system for a secondary usage of a wire rope, comprising:
the steel wire rope acquisition module is used for acquiring a plurality of steel wire ropes with the same specification; the service time of the plurality of steel wire ropes is different;
the loss rate determining module is used for determining the loss rate of each steel wire rope;
the effective rate determining module is used for determining the effective rate of the steel wire rope according to the loss rate;
the total utility relative change rate determining module is used for determining the total utility relative change rate of each steel wire rope;
the linear fitting module is used for carrying out linear fitting by taking the effective rates of the plurality of steel wire ropes as independent variables and taking the total utility relative change rate of the plurality of steel wire ropes as dependent variables to obtain an effective rate-total utility relative change rate relation model;
the life determining model construction module is used for constructing a Hamilton function based on the relation model of the effective rate and the total effective rate and solving the Hamilton function by utilizing the relation between the residual effective performance utility value and the loss rate of the steel wire rope to obtain a life determining model; the independent variable of the life determining module is the service time; the dependent variable of the life determining module is a residual effective performance utility value;
and the service life evaluation module is used for inputting the service time of the steel wire rope to be tested into the service life determination model to obtain the residual effective performance utility value of the steel wire rope to be tested.
9. An electronic device comprising a memory for storing a computer program and a processor that runs the computer program to cause the electronic device to perform the method of any one of claims 1 to 7.
10. The electronic device of claim 9, wherein the memory is a readable storage medium.
CN202310787840.6A 2023-06-30 2023-06-30 Method, system and equipment for determining physical life of secondary utilization steel wire rope Pending CN116776616A (en)

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