Crane lifting trolley frame fatigue test method and system

Abstract

The invention discloses a crane lifting trolley frame fatigue test method and system, and the method comprises the steps: 1), obtaining the fatigue related characteristic data of a crane lifting trolley frame in the actual operation process of a crane; 2) determining fatigue test parameter setting of the crane lifting trolley frame according to the obtained characteristic data, and testing the crane lifting trolley frame according to the fatigue test parameter setting; 3) circularly executing the test until a preset test termination condition is met, and recording fatigue crack data of the crane lifting trolley frame in the test process during the test; and 4) estimating the fatigue life of the crane lifting trolley frame according to the test result of the crane lifting trolley frame. According to the fatigue test designed by the invention, the influence of vibration and load stress on the crane lifting trolley frame is comprehensively considered, and the fatigue life of the crane lifting trolley frame can be accurately estimated, so that the safety of crane operation is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of fatigue testing of a lifting trolley, and in particular to a method and system for fatigue testing a lifting trolley frame of a crane. Background Art

[0002] A crane refers to a multi-action lifting machine that can lift heavy objects vertically and carry them horizontally within a certain range. It is the main lifting equipment for loading and unloading operations in ports, factories and other places. It has the working characteristics of short, repetitive, periodic cycles, frequent starting and braking, and large impact loads. As one of the main load-bearing components in the crane, the lifting trolley frame is mainly affected by vibration and stress loads during operation. Fatigue damage will inevitably occur in the process of bearing its own weight, alternating working loads and vibration loads for a long time. When the fatigue damage accumulates to a certain extent, fatigue cracks will appear. After that, the cracks will further expand under the action of external loads, and eventually lead to structural damage, resulting in serious consequences. Therefore, it is of great significance to conduct fatigue tests on the crane lifting trolley frame to test its performance.

[0003] To this end, the present invention provides a crane hoisting trolley frame fatigue test method and system, which can effectively estimate the fatigue life of the crane hoisting trolley frame through the test, which is of great significance for ensuring the safe production of the crane. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a crane hoisting trolley frame fatigue test method and system, which can effectively estimate the fatigue life of the crane hoisting trolley frame to ensure the safety of crane operation.

[0005] In order to achieve the above technical purpose, the technical solution adopted by the present invention is: a fatigue test method for a crane hoisting trolley frame, comprising:

[0006] Step 1): Obtain fatigue-related characteristic data of the crane hoisting trolley frame during the actual operation of the crane;

[0007] Step 2): determining a fatigue test parameter setting of a crane hoisting trolley frame according to the acquired characteristic data, and testing the crane hoisting trolley frame with the fatigue test parameter setting;

[0008] Step 3): the test is executed cyclically until the preset test termination condition is met, during which the fatigue crack data of the crane hoisting trolley frame during the test is recorded;

[0009] Step 4): According to the test results of the crane hoisting trolley frame, estimate the fatigue life of the crane hoisting trolley frame.

[0010] As a possible implementation, further, the fatigue-related characteristic data in step 1) includes stress, strain and vibration frequency of the target position of the crane lifting trolley frame at each moment.

[0011] As a possible implementation, further, in step 2), the fatigue test parameter setting of the crane hoisting trolley frame is determined according to the acquired characteristic data, and the crane hoisting trolley frame is tested with the fatigue test parameter setting, which specifically includes the following steps:

[0012] Step 2.1): Count the action time of each stress and each vibration frequency of the crane lifting trolley frame at the target position according to the acquired characteristic data;

[0013] Step 2.2): sort the stress and vibration frequency of the crane hoisting trolley frame at the target position from large to small according to the action duration, and select the top n stresses and vibration frequencies in order;

[0014] Among them, the sum of the action durations corresponding to the top n stresses selected in the ranking accounts for no less than 80% of the total stress action duration; the action durations corresponding to the top n vibration frequencies selected in the ranking accounts for no less than 80% of the total vibration duration;

[0015] Step 2.3): Set the action time Ti of each stress in a single load cycle according to the ratio of the action time corresponding to each stress in the first n order;

[0016] According to the ratio of the action time corresponding to each vibration frequency in the first n order, the action time Hi of each vibration frequency in a single load cycle is set;

[0017] Step 2.4): According to the first n screened stresses and vibration frequencies and the action time of each stress and vibration frequency during a single load cycle, the fatigue test parameters are set accordingly, and the target position of the crane lifting trolley frame is tested with the fatigue test parameter settings.

[0018] As a possible implementation, further, the Ti expression in step 2.3) is as follows:

[0019]

[0020] Where Ti represents the duration of action of the i-th stress among the first n stresses in a single load cycle; t i It represents the action duration corresponding to the i-th stress among the first n stresses in the fatigue-related characteristic data, t n It represents the action duration corresponding to the nth stress in the first n stresses in the fatigue-related characteristic data; A represents the duration of a single load cycle;

[0021] The Hi expression is as follows:

[0022]

[0023] Where Hi represents the duration of action of the i-th vibration frequency among the first n vibration frequencies in a single load cycle; h i It represents the action duration corresponding to the i-th vibration frequency among the first n vibration frequencies in the fatigue-related characteristic data, h n It represents the action duration corresponding to the nth vibration frequency among the first n vibration frequencies in the fatigue-related characteristic data; A represents the duration of a single load cycle.

[0024] As a possible implementation mode, further, n stresses and vibration frequencies selected during each load cycle are applied to the crane lifting trolley frame in a random order, and the target position of the crane lifting trolley frame is tested.

[0025] As a possible implementation, further, step 3): the test is executed cyclically until a preset test termination condition is met, during which fatigue crack data of the crane hoisting trolley frame during the test is recorded. The specific steps are as follows:

[0026] The test is performed cyclically, during which the fatigue crack size data of the crane hoisting trolley frame during the test is recorded in real time;

[0027] The test is terminated when the fatigue crack size data exceeds the critical crack length or the number of load cycles reaches the set number; among which, the set number of load cycles should be greater than the number of cycles corresponding to the appearance of fatigue cracks in the crane hoisting trolley frame.

[0028] As a possible implementation, further, step 4): according to the test results of the crane hoisting trolley frame, the fatigue life of the crane hoisting trolley frame is estimated, and the specific steps are as follows:

[0029] When the fatigue crack size data exceeds the critical crack length, the number of cycles corresponding to the moment when the fatigue crack size data exceeds the critical crack length is taken as the fatigue life of the crane hoisting trolley frame;

[0030] When the number of load cycles reaches the set number, the fatigue life of the crane hoisting trolley frame is estimated based on the fatigue crack size data, the number of load cycles and the fatigue test setting parameters.

[0031] As a possible implementation method, further, the fatigue life of the crane hoisting trolley frame is estimated according to the fatigue crack size data, the number of cycles and the fatigue test parameters. The specific steps are as follows:

[0032] According to the fatigue crack size data, the number of load cycles and the fatigue test setting parameters, the fatigue life N of the crane hoisting trolley frame is estimated. f , where N f The expression of is as follows;

[0033]

[0034] Among them, N0 represents the number of cycles corresponding to the occurrence of fatigue cracks on the crane hoisting trolley frame; a0 represents the initial crack length when fatigue cracks just appear on the crane hoisting trolley frame; a f represents the critical crack length; σ min Indicates the minimum stress during the load cycle; Δσ indicates the stress increase, Δσ=σ max -σ min , σ max Indicates the maximum stress during the load cycle; C and m are the same as C and m in the Pais formula, where C and m are material constants (determined by experiments); p is an empirical parameter, usually set between 0.2 and 0.5;

[0035] F f Indicates the frequency correction factor, F f The expression is as follows:

[0036]

[0037] Among them, α is a constant related to the material. Since the crane hoisting trolley frame is usually made of steel, α is usually set between 0.1 and 0.5; The expression is as follows:

[0038]

[0039] In the above formula, n represents the number of vibration frequencies screened; f i Indicates the frequency value of the ith vibration frequency among the first n vibration frequencies screened (unit: Hz); h i It represents the action duration corresponding to the i-th vibration frequency among the first n vibration frequencies in the fatigue-related characteristic data, h n Indicates the action duration corresponding to the nth vibration frequency among the top n vibration frequencies in the fatigue-related characteristic data.

[0040] The present invention also provides a crane hoisting trolley frame fatigue test system, which uses the above-mentioned crane hoisting trolley frame fatigue test method, and the system includes:

[0041] A data acquisition module is used to acquire fatigue-related characteristic data of the crane hoisting trolley frame during the actual operation of the crane;

[0042] A data processing module, used to determine the fatigue test parameter setting of the crane hoisting trolley frame according to the acquired characteristic data;

[0043] A parameter setting module is used to set the test device accordingly according to the determined fatigue test parameters and the preset test termination conditions;

[0044] A test device, used for applying stress and vibration to a target position of a crane hoisting trolley frame according to settings, and cyclically performing a test on the crane hoisting trolley frame until a preset test termination condition is met;

[0045] Image recognition module, used to obtain and record fatigue crack data of the crane hoisting trolley frame during the test;

[0046] The fatigue life estimation module is used to estimate the fatigue life of the crane hoisting trolley frame according to the test results of the crane hoisting trolley frame.

[0047] The present invention also provides a computer-readable storage medium, in which at least one instruction, at least one program, code set or instruction set is stored. The at least one instruction, at least one program, code set or instruction set is loaded and executed by a processor to implement the above-mentioned crane hoisting trolley frame fatigue test method.

[0048] By adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art:

[0049] 1) The fatigue test designed in the present invention comprehensively considers the influence of vibration and load stress on the crane hoisting trolley frame, and can accurately estimate the fatigue life of the crane hoisting trolley frame to ensure the safety of crane operation.

[0050] 2) The present invention sets relevant experimental parameters based on characteristic data detected during the actual operation of the crane hoisting trolley frame, so that the results obtained from the experiment can be closer to reality, thereby further improving the accuracy of the fatigue life estimation of the crane hoisting trolley frame. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0052] Figure 1 It is a brief schematic diagram of a fatigue test method for a crane hoisting trolley frame provided by an embodiment of the present invention;

[0053] Figure 2 It is a schematic diagram of a system implementation structure of a crane hoisting trolley frame fatigue test method corresponding to the solution of the present invention;

[0054] Figure 3 It is a schematic diagram of a computer-readable storage medium provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0055] The present invention will be further described in detail below in conjunction with the accompanying drawings and examples. It is particularly noted that the following examples are only used to illustrate the present invention, but are not intended to limit the scope of the present invention. Similarly, the following examples are only partial embodiments of the present invention rather than all embodiments, and all other embodiments obtained by those of ordinary skill in the art without creative work are within the scope of protection of the present invention.

[0056] Embodiment 1

[0057] Refer to the attached Figure 1 As shown, this embodiment provides a crane hoisting trolley frame fatigue test method, comprising the following steps:

[0058] Step 1): Obtain fatigue-related characteristic data of the crane hoisting trolley frame during the actual operation of the crane; wherein the fatigue-related characteristic data includes data such as stress, strain and vibration frequency of the target position of the crane hoisting trolley frame at each moment.

[0059] Step 2): Determine the fatigue test parameter setting of the crane hoisting trolley frame according to the acquired characteristic data, and test the crane hoisting trolley frame with the fatigue test parameter setting, specifically including the following steps:

[0060] Step 2.1): Count the action time of each stress and each vibration frequency of the crane lifting trolley frame at the target position according to the acquired characteristic data;

[0061] Step 2.2): sort the stresses and vibration frequencies of the crane hoisting trolley frame at the target position from large to small according to the action duration, and select the first n stresses and vibration frequencies in order; the number of selected stresses and vibration frequencies can be the same or different.

[0062] Among them, the sum of the action durations corresponding to the top n stresses screened out in the ranking accounts for no less than 80% of the total stress action duration (in actual operation, the proportion is usually set between 80% and 90%); the sum of the action durations corresponding to the top n vibration frequencies screened out in the ranking accounts for no less than 80% of the total vibration duration (in actual operation, the proportion is usually set between 80% and 90%).

[0063] For ease of understanding, an example is given here to illustrate. For example, the stresses to which the crane hoisting trolley frame is subjected during the actual operation of the crane include: σ1, σ2, σ3, σ4, and the corresponding action time of each stress is t1, t2, t3, t4 (where t1<t4<t2<t3); similarly, the vibration frequencies to which the crane hoisting trolley frame is subjected during the actual operation of the crane include: f1, f2, f3, f4, and the corresponding action time of each vibration frequency is h1, h2, h3, h3, h4 (where h1<h2<h3<h4). Among them, the stresses are sorted from large to small according to the action time, namely σ3, σ2, σ4, σ1, and similarly, the vibration frequencies are sorted from large to small according to the action time, namely f4, f3, f2, f1.

[0064] The first n stresses are screened out in order, and the sum of the action durations corresponding to the first n stresses screened out in order accounts for no less than 80% of the total stress action duration; for example, the first two stresses σ3 and σ2 are screened out, and the sum of the action durations corresponding to σ3 and σ2 (t3+t2) accounts for no less than 80% of the total stress action duration (t1+t2+t3+t4), that is, (t3+t2) / (t1+t2+t3+t4)≥80%; for example, if the sum of the action durations corresponding to the current two stresses is less than 80% of the total stress action duration, the first three stresses are screened out, that is, this step must ensure that the sum of the action durations corresponding to the first n stresses screened out in order is no less than 80% of the total stress action duration. Similarly, this step must ensure that the sum of the action durations corresponding to the first n vibration frequencies screened out in order is no less than 80% of the total vibration duration.

[0065] Step 2.3): Set the duration Ti of each stress in a single load cycle according to the ratio of the duration of each stress in the first n order; where Ti is expressed as follows:

[0066]

[0067] In the above formula, Ti represents the duration of action of the i-th stress among the first n stresses in a single load cycle; t i It represents the action duration corresponding to the i-th stress among the first n stresses in the fatigue-related characteristic data, t n It represents the action duration corresponding to the nth stress among the top n stresses in the fatigue-related characteristic data; A represents the duration of a single load cycle.

[0068] For ease of understanding, an example is given here to illustrate. In the same example as above, for example: the first two stresses σ3 and σ2 are screened out, where the corresponding action durations of σ3 and σ2 satisfy (t3+t2) / (t1+t2+t3+t4)≥80%; then among the first two screened stresses σ3 and σ2, the action duration of the first stress σ3 during a single load cycle is: T1=A×t3 / (t3+t2); the action duration of the second stress σ2 during a single load cycle is: T2=A×t2 / (t3+t2).

[0069] The action duration Hi of each vibration frequency in a single load cycle is set according to the ratio of the action duration corresponding to each vibration frequency in the first n order; wherein, the expression of Hi is as follows:

[0070]

[0071] In the above formula, Hi represents the duration of action of the i-th vibration frequency among the first n vibration frequencies in a single load cycle; h i It represents the action duration corresponding to the i-th vibration frequency among the first n vibration frequencies in the fatigue-related characteristic data, h n It represents the action duration corresponding to the nth vibration frequency among the first n vibration frequencies in the fatigue-related characteristic data; A represents the duration of a single load cycle.

[0072] For ease of understanding, an example is given here to illustrate. In the same example as above, for example: the first three vibration frequencies f4, f3, and f2 are screened out, and the corresponding action durations of f4, f3, and f2 satisfy (h4+h3+h2) / (h4+h3+h2+h1)≥80%; then among the first three vibration frequencies f4, f3, and f2 screened out, the action duration of the first vibration frequency f4 during a single load cycle is: T1=A×h4 / (h4+h3+h2); the action duration of the second vibration frequency f3 during a single load cycle is: T2=A×h3 / (h4+h3+h2); the action duration of the third vibration frequency f2 during a single load cycle is: T3=A×h2 / (h4+h3+h2).

[0073] Step 2.4): According to the first n selected stresses, vibration frequencies and the action time of each stress and vibration frequency in a single load cycle, the fatigue test parameters are set accordingly, and the target position of the crane lifting trolley frame is tested with the fatigue test parameter setting. The n selected stresses and vibration frequencies in each load cycle act on the crane lifting trolley frame in a random order, and the target position of the crane lifting trolley frame is tested. For example: the first two stresses σ3 and σ2 are selected to act on the crane lifting trolley frame. In the first load cycle, the stress action sequence can be σ3, σ2, or σ2, σ3; in the second load cycle, the stress action sequence can be σ2, σ3, or σ3, σ2; that is, the action sequence of σ3 and σ2 in each load cycle is random. The action sequence of vibration frequency in each load cycle is also random. In the test process, the stress and vibration frequency act on the crane lifting trolley frame at the same time, rather than acting on the crane lifting trolley frame alternately, that is, the crane lifting trolley frame is subjected to vibration and stress at the same time.

[0074] In the above steps, relevant test parameters are set according to the characteristic data detected during the actual operation of the crane hoisting trolley frame, so that the test results can be closer to reality, which can effectively improve the accuracy of the fatigue life estimation of the crane hoisting trolley frame.

[0075] Step 3): The test is executed repeatedly until the preset test termination condition is met, during which the fatigue crack data of the crane hoisting trolley frame during the test is recorded. The specific steps are as follows:

[0076] The test is performed cyclically, during which the fatigue crack size data of the crane hoisting trolley frame during the test is recorded in real time;

[0077] Fatigue crack size data exceeds the critical crack length a f Or when the load cycle number reaches the set number, the test is terminated; the set load cycle number should be greater than the cycle number corresponding to the fatigue cracks on the crane hoisting trolley frame. For example: after N0 load cycles, cracks appear on the crane hoisting trolley frame. The load cycle number set in the test is N set It should be greater than the load cycle N0 at which cracks appear on the crane hoisting trolley frame.

[0078] Step 4): Based on the test results of the crane hoisting trolley frame, estimate the fatigue life of the crane hoisting trolley frame as follows:

[0079] When the fatigue crack size exceeds the critical crack length (critical crack length a f is the preset value), the fatigue crack size data exceeds the critical crack length a fAt that moment, the corresponding number of cycles is taken as the fatigue life of the crane hoisting trolley frame; for example: when the fatigue crack size on the crane hoisting trolley frame exceeds the critical crack length at 90,000 load cycles, the fatigue life of the crane hoisting trolley frame is 90,000 times.

[0080] When the number of load cycles reaches the set number, the fatigue life of the crane hoisting trolley frame is estimated based on the fatigue crack size data, the number of load cycles and the fatigue test setting parameters. The specific steps are as follows:

[0081] According to the fatigue crack size data, the number of load cycles and the fatigue test setting parameters, the fatigue life N of the crane hoisting trolley frame is estimated. f (Based on Walker equation), where N f The expression of is as follows;

[0082]

[0083] Among them, N0 represents the number of cycles corresponding to the occurrence of fatigue cracks on the crane hoisting trolley frame; a0 represents the initial crack length when fatigue cracks just appear on the crane hoisting trolley frame; a f Indicates the critical crack length (when the crack length is greater than a f , it is determined that the crane lifting trolley frame cannot be used any more); σ min Indicates the minimum stress during the load cycle; Δσ indicates the stress increase, Δσ=σ max -σ min , σ max It represents the maximum value of stress during the load cycle. Since the stress used in each load cycle is the first n stresses screened out, the Δσ value is the same in each load cycle. p is an empirical parameter, usually set between 0.2 and 0.5. C and m are the same as C and m in the Pais formula, where C and m are material constants (determined by experiments, and the determination method of C and m in the Pais formula is the existing technology and will not be repeated here). The Pais formula is as follows:

[0084]

[0085] Where C and m are material constants, and ΔK represents the stress intensity factor increment.

[0086] N f In the expression, F f Indicates the frequency correction factor, F f The expression is as follows:

[0087]

[0088] Among them, α is a constant related to the material. Since the crane lifting trolley frame is usually made of steel, α is usually set between 0.1 and 0.5. The expression is as follows:

[0089]

[0090] In the above formula, n represents the number of vibration frequencies screened; f i Indicates the frequency value of the ith vibration frequency among the first n vibration frequencies screened (unit: Hz); h i It represents the action duration corresponding to the i-th vibration frequency among the first n vibration frequencies in the fatigue-related characteristic data, h n Indicates the action duration corresponding to the nth vibration frequency among the top n vibration frequencies in the fatigue-related characteristic data.

[0091] As a further improvement, the above p and α can be further determined by measuring the crack growth rate under different vibration and stress load conditions and fitting by the least square method to further improve the fatigue life N of the crane hoisting trolley frame. f Accuracy of estimates.

[0092] Embodiment 2

[0093] See attached Figure 2 As shown, this implementation example provides a crane hoisting trolley frame fatigue test system, which applies the crane hoisting trolley frame fatigue test method in embodiment 1, and the system includes:

[0094] A data acquisition module is used to acquire fatigue-related characteristic data of the crane hoisting trolley frame during the actual operation of the crane;

[0095] A data processing module, used to determine the fatigue test parameter setting of the crane hoisting trolley frame according to the acquired characteristic data;

[0096] A parameter setting module is used to set the test device accordingly according to the determined fatigue test parameters and the preset test termination conditions;

[0097] A test device, used for applying stress and vibration to a target position of a crane hoisting trolley frame according to settings, and cyclically performing a test on the crane hoisting trolley frame until a preset test termination condition is met;

[0098] Image recognition module, used to obtain and record fatigue crack data of the crane hoisting trolley frame during the test;

[0099] The fatigue life estimation module is used to estimate the fatigue life of the crane hoisting trolley frame according to the test results of the crane hoisting trolley frame.

[0100] Embodiment 3

[0101] See attached Figure 3 As shown, based on the same inventive concept, an embodiment of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer instructions. When the computer instructions are executed on a computer, the computer executes the crane lifting trolley frame fatigue test method as described in Embodiment 1.

[0102] In the specific implementation process, computer-readable storage media include: Universal Serial Bus flash drive (USB), mobile hard disk, read-only memory (ROM), random access memory (RAM), magnetic disk or optical disk, and other storage media that can store program codes.

[0103] The device embodiments described above are merely illustrative, wherein the units / modules described as separate components may or may not be physically separated, and the components displayed as units / modules may or may not be physical units / modules, i.e., they may be located in one place, or they may be distributed over multiple network units / modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Those of ordinary skill in the art may understand and implement it without creative effort.

[0104] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0105] The above descriptions are only some embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Any equivalent device or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A fatigue test method for a crane hoisting trolley frame, characterized in that: include: Step 1): Obtain fatigue-related characteristic data of the crane hoisting trolley frame during the actual operation of the crane; Step 2): determining the fatigue test parameter setting of the crane hoisting trolley frame according to the acquired characteristic data, and testing the crane hoisting trolley frame with the fatigue test parameter setting; Step 3): the test is executed cyclically until the preset test termination condition is met, during which the fatigue crack data of the crane hoisting trolley frame during the test is recorded; Step 4): Based on the test results of the crane hoisting trolley frame, estimate the fatigue life of the crane hoisting trolley frame.

2. The crane hoisting trolley frame fatigue test method according to claim 1 is characterized in that: The fatigue-related characteristic data in step 1) include the stress, strain and vibration frequency of the target position of the crane lifting trolley frame at each moment.

3. The crane hoisting trolley frame fatigue test method according to claim 2 is characterized in that: In step 2), the fatigue test parameter setting of the crane hoisting trolley frame is determined according to the acquired characteristic data, and the crane hoisting trolley frame is tested with the fatigue test parameter setting, which specifically includes the following steps: Step 2.1): Count the action duration of each stress and each vibration frequency of the crane lifting trolley frame at the target position according to the acquired characteristic data; Step 2.2): sort the stress and vibration frequency of the crane hoisting trolley frame at the target position from large to small according to the action duration, and select the top n stresses and vibration frequencies in order; Among them, the sum of the action durations corresponding to the top n stresses selected in the ranking accounts for no less than 80% of the total stress action duration; the action durations corresponding to the top n vibration frequencies selected in the ranking accounts for no less than 80% of the total vibration duration; Step 2.3): Set the action time Ti of each stress in a single load cycle according to the ratio of the action time corresponding to each stress in the first n order; According to the ratio of the action time corresponding to each vibration frequency in the first n order, the action time Hi of each vibration frequency in a single load cycle is set; Step 2.4): According to the first n screened stresses and vibration frequencies and the action time of each stress and vibration frequency during a single load cycle, the fatigue test parameters are set accordingly, and the target position of the crane lifting trolley frame is tested with the fatigue test parameter settings.

4. The crane hoisting trolley frame fatigue test method according to claim 3 is characterized in that: In step 2.3), the Ti expression is as follows: Where Ti represents the duration of action of the i-th stress among the first n stresses in a single load cycle; t i It represents the action duration corresponding to the i-th stress among the first n stresses in the fatigue-related characteristic data, t n It represents the action duration corresponding to the nth stress in the first n stresses in the fatigue-related characteristic data; A represents the duration of a single load cycle; The Hi expression is as follows: Where Hi represents the duration of action of the i-th vibration frequency among the first n vibration frequencies in a single load cycle; h i It represents the action duration corresponding to the i-th vibration frequency among the first n vibration frequencies in the fatigue-related characteristic data, h n It represents the action duration corresponding to the nth vibration frequency among the first n vibration frequencies in the fatigue-related characteristic data; A represents the duration of a single load cycle.

5. The crane hoisting trolley frame fatigue test method according to claim 4 is characterized in that: During each load cycle, n selected stresses and vibration frequencies are applied to the crane hoisting trolley frame in a random order, and the target position of the crane hoisting trolley frame is tested.

6. The crane hoisting trolley frame fatigue test method according to claim 1 is characterized in that: Step 3): The test is executed repeatedly until the preset test termination condition is met, during which the fatigue crack data of the crane hoisting trolley frame during the test is recorded. The specific steps are as follows: The test is performed cyclically, during which the fatigue crack size data of the crane hoisting trolley frame during the test is recorded in real time; The test is terminated when the fatigue crack size data exceeds the critical crack length or the number of load cycles reaches the set number; among which, the set number of load cycles should be greater than the number of cycles corresponding to the appearance of fatigue cracks in the crane hoisting trolley frame.

7. The crane hoisting trolley frame fatigue test method according to claim 4 is characterized in that: Step 4): According to the test results of the crane hoisting trolley frame, estimate the fatigue life of the crane hoisting trolley frame. The specific steps are as follows: When the fatigue crack size data exceeds the critical crack length, the number of cycles corresponding to the moment when the fatigue crack size data exceeds the critical crack length is taken as the fatigue life of the crane hoisting trolley frame; When the number of load cycles reaches the set number, the fatigue life of the crane hoisting trolley frame is estimated based on the fatigue crack size data, the number of load cycles and the fatigue test setting parameters.

8. The crane hoisting trolley frame fatigue test method according to claim 7 is characterized in that: Based on the fatigue crack size data, the number of load cycles and the fatigue test setting parameters, the fatigue life of the crane hoist trolley frame is estimated. The specific steps are as follows: According to the fatigue crack size data, the number of load cycles and the fatigue test setting parameters, the fatigue life N of the crane hoisting trolley frame is estimated. f , where N f The expression of is as follows; Wherein, N0 represents the number of cycles corresponding to the occurrence of fatigue cracks in the crane hoisting trolley frame; a0 represents the initial crack length when fatigue cracks occur in the crane hoisting trolley frame; a f represents the critical crack length; σ min Indicates the minimum stress during the load cycle; Δσ indicates the stress increase, Δσ=σ max -σ min , σ rnax Indicates the maximum stress during the load cycle; C and m are the same as C and m in the Pais formula, where C and m are material constants; p is an empirical parameter, usually set between 0.2 and 0.5; F f Indicates the frequency correction factor, F f The expression is as follows: Among them, α is a constant related to the material; The expression is as follows: In the above formula, n represents the number of vibration frequencies screened; f i represents the frequency value of the i-th vibration frequency among the first n vibration frequencies screened out; h i It represents the action duration corresponding to the i-th vibration frequency among the first n vibration frequencies in the fatigue-related characteristic data, h n Indicates the action duration corresponding to the nth vibration frequency among the top n vibration frequencies in the fatigue-related characteristic data.

9. A crane hoisting trolley frame fatigue test system, characterized in that: The method for fatigue testing a crane hoisting trolley frame according to any one of claims 1 to 8 is applied, wherein the system comprises: A data acquisition module is used to acquire fatigue-related characteristic data of the crane hoisting trolley frame during the actual operation of the crane; A data processing module, used to determine the fatigue test parameter setting of the crane hoisting trolley frame according to the acquired characteristic data; A parameter setting module is used to set the test device accordingly according to the determined fatigue test parameters and the preset test termination conditions; A test device, used for applying stress and vibration to a target position of a crane hoisting trolley frame according to settings, and cyclically performing a test on the crane hoisting trolley frame until a preset test termination condition is met; Image recognition module, used to obtain and record fatigue crack data of the crane hoisting trolley frame during the test; The fatigue life estimation module is used to estimate the fatigue life of the crane hoisting trolley frame according to the test results of the crane hoisting trolley frame.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the crane hoisting trolley frame fatigue test method according to any one of claims 1 to 8 is implemented.

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