A pendulum impact machine digital model establishing method

Abstract

The present application relates to the technical field of structural mechanics, in particular to a pendulum impact machine digital model establishing method, the stiffness of the spiral spring around the concrete base, the stiffness of the anvil upward movement, the stiffness and damping of the anvil back, the connecting stiffness between the lining rail and the anvil, the supporting channel steel participating mass, the supporting channel steel warping damping, the connecting stiffness and action damping between the test equipment and the pendulum impact machine are obtained respectively, then in the finite element analysis software, according to the concrete base mass, the anvil mass, the lining rail mass, the supporting channel steel participating mass, the test equipment mass, the stiffness of the spiral spring around the concrete base, the anvil guide bolt stiffness, the connecting stiffness between the lining rail and the anvil, the supporting channel steel stiffness, the connecting stiffness of the test equipment mass, the anvil guide bolt back damping, the supporting channel steel warping damping and the test equipment action damping, the pendulum impact machine multi-freedom dynamics model is established, which can replace the impact machine to carry out equipment impact test.

Description

Technical Field

[0001] This invention relates to the field of structural mechanics technology, specifically to a method for establishing a digital model of a pendulum impact machine. Background Technology

[0002] During the design process of nuclear power equipment, due to its different usage scenarios and load environments, the impact environment suffered by the nuclear power equipment must be considered. Safety level 1 equipment needs to meet the requirements of impact resistance design specifications. The medium impact tester, as a standard-certified impact testing and evaluation device, is used to simulate the response of equipment after being subjected to impact. It undertakes a large number of important equipment impact tests and evaluations, providing input and evaluation results for the impact-resistant structural integrity design of various types of nuclear power equipment.

[0003] Currently, the pendulum-type medium impact tester, due to its large test load range (200kg-2700kg), can perform lateral and vertical impact tests on equipment, basically covering the impact resistance test requirements of nuclear power equipment. However, using the pendulum-type medium impact tester for equipment impact testing also has limitations. Typically, due to time and cost considerations, only one impact test is conducted. But nuclear power equipment impact testing specifications require at least three independent impact tests, and these tests are destructive, significantly increasing the testing cost.

[0004] Furthermore, because pendulum-type medium-sized impact testers cannot be mass-produced, the number of impact testers available in China for nuclear power equipment impact testing is currently limited. Relying solely on existing pendulum-type medium-sized impact testers for on-site testing is insufficient to meet current needs and the progress of design tasks. Moreover, with the development of digitalization, establishing a digital virtual testing machine model for pendulum-type medium-sized impact testers and using simulation methods to address current requirements is of great significance.

[0005] Furthermore, due to the complexity of the impact machine's structure and operating process, involving the direct connections between various components, establishing a digital simulation model of the impact machine presents certain difficulties and challenges. The pendulum-type medium-sized impact machine's base and pendulum rotation shaft support are firmly fixed to a common concrete foundation; the anvil is a welded frame structure, connected to the impact machine base by multiple guide bolts, and limited and buffered by hydraulic cylinders at the four corners; the liner is rigidly mounted on the anvil with bolts; the support channel steel is mounted on the liner with bolts and pressure blocks, its boundary conditions falling between simply supported and fixed; the test equipment is mounted on the support channel steel via T-shaped pressure blocks with bolts. It can be seen that from the anvil → liner → support channel steel → test equipment, there are multiple joint surfaces, and the connection state between them directly affects whether the load transfer process can be accurately simulated, that is, the reliability of the digital model.

[0006] The inventors discovered in their research that most current nuclear power equipment impact tests rely on pendulum-type medium impact machines. However, the limited number of pendulum-type medium impact machines, high testing costs, and long testing times make them unsuitable for actual engineering schedules. There is an urgent need to establish a digital model of the pendulum-type medium impact machine to replace the actual impact testing and complete virtual simulation impact testing. Furthermore, there is currently no simulation model specifically designed for the complex action process of the pendulum-type impact machine. Existing simulation models of other types of impact machines are mostly three-dimensional models with extremely large mesh and computational loads, resulting in significant uncertainties and making them unsuitable for effectively replacing impact machines in completing impact testing. Summary of the Invention

[0007] To address the technical problem that existing impact test models cannot effectively replace impact test machines in completing assessment impact tests, this invention provides a method for establishing a digital model of a pendulum impact test machine. This method describes the structure and impact process of the pendulum impact test machine in a parametric manner, and can replace the pendulum impact test machine to complete virtual impact assessment tests of equipment and obtain the equipment impact environment. This enables the digitization of impact assessment tests for nuclear power equipment, thereby improving test efficiency.

[0008] This invention is achieved through the following technical solution:

[0009] This invention provides a method for establishing a digital model of a pendulum impact machine, comprising the following steps:

[0010] S10. Based on the sum of the concrete foundation mass and the mass of the impactor base during the construction of the pendulum impactor, as well as the first-order installation frequency of the impactor base, the stiffness of the helical springs around the concrete base is calculated.

[0011] S20. Based on the axial stiffness of the single guide bolt between the anvil and the base of the pendulum impact machine and the number of bolts, calculate the stiffness of the anvil moving upward, and based on the buffer stiffness and damping of the pendulum impact machine, calculate the stiffness and damping of the anvil falling back.

[0012] S30. Calculate the connection stiffness between the rail and the anvil based on the total axial stiffness of the bolts and the flange stiffness between the rail and the anvil.

[0013] S40. Based on the modal mass of a single support channel steel under simply supported constraints at both ends, determine the mass involved in the support channel steel and calculate the warping damping of the support channel steel.

[0014] S50. Determine the connection stiffness and action damping between the tested equipment and the pendulum impact machine based on the mass of the tested equipment, the actual installation method, and the operating frequency.

[0015] S60. Based on the mass of the concrete foundation, the mass of the anvil, the mass of the liner rail, the mass of the supporting channel steel, the mass of the tested equipment, the stiffness of the helical springs around the concrete base, the stiffness of the anvil guide bolts, the connection stiffness between the liner rail and the anvil, the stiffness of the supporting channel steel, the connection stiffness of the tested equipment mass, the fallback damping of the anvil guide bolts, the warping damping of the supporting channel steel, and the motion damping of the tested equipment, a multi-free dynamic model of the pendulum impact machine is established in the finite element analysis software.

[0016] The present invention provides a method for establishing a digital model of a pendulum impact tester. First, the stiffness of the helical springs around the concrete base, the stiffness of the anvil's upward movement, the stiffness and damping of the anvil's fall, the connection stiffness between the liner and the anvil, the mass of the supporting channel steel, the warping damping of the supporting channel steel, and the connection stiffness and motion damping between the tested equipment and the pendulum impact tester are obtained. Then, in finite element analysis software, based on the mass of the concrete foundation, the mass of the anvil, the mass of the liner, the mass of the supporting channel steel, the mass of the tested equipment, the stiffness of the helical springs around the concrete base, the stiffness of the anvil guide bolts, the connection stiffness between the liner and the anvil, the stiffness of the supporting channel steel, the connection stiffness of the tested equipment's mass, the fall damping of the anvil guide bolts, the warping damping of the supporting channel steel, and the motion damping of the tested equipment, a multi-free dynamic model of the pendulum impact tester is established. This digital model of the pendulum impact tester can replace a real impact tester for equipment impact assessment tests, thereby solving the problems of the current limited number of pendulum impact testers, high testing costs, and long testing times, and greatly improving the balance between testing efficiency and project progress.

[0017] Furthermore, the pendulum impact machine model established using this invention is a digital model, which can avoid large-scale mesh and computational workload, and make up for the shortcomings of existing numerical models that cannot accurately simulate the impact machine's action process. It can quickly and accurately complete the virtual test of equipment impact assessment and obtain the impact assessment environment.

[0018] Meanwhile, the present invention provides a method for establishing a digital model of a pendulum impact machine that involves few parameters and has high accuracy, and can be applied to the establishment of numerical models for all pendulum impact machines.

[0019] Specifically, in S10, the calculation model for the stiffness of the helical springs around the concrete base is k1=(2πf1). 2 ·m1;

[0020] In the formula:

[0021] f1 is the first-order natural installation frequency of the impact machine base.

[0022] m1 represents the mass of the concrete foundation.

[0023] k1 represents the stiffness of the helical springs surrounding the concrete base.

[0024] Specifically, in S20:

[0025] The calculation model for the axial stiffness of a single guide bolt is as follows: In the formula, E is the elastic modulus of the guide bolt material, A is the minimum cross-sectional area of ​​the guide bolt, and l is the working length of the guide bolt;

[0026] The stiffness calculation model for the upward motion of the anvil is k. up =n 轴 ·k 轴 In the formula, n 轴 k represents the number of guide bolts. up Let be the stiffness of the anvil as it moves upward.

[0027] Specifically, in S20, the calculation model for the anvil's fall damping is as follows: In the formula, c2 is the damping of the guide bolt falling back, ξ is the damping coefficient, and k 缓冲 For the stiffness of the buffer spring inside the hydraulic cylinder of the pendulum impact machine, n 缓冲 m2 represents the number of buffer springs inside the hydraulic cylinder of the pendulum impact machine, and m2 represents the mass of the anvil of the pendulum impact machine.

[0028] Specifically, when the anvil moves upward, the stiffness k2 of the anvil guide bolt is set to 0 when the displacement is between 0 and L1, and to k when the displacement is greater than L1. up ;

[0029] When the anvil moves downwards, the stiffness k2 of the anvil guide bolt is set to k. down ;

[0030] Where L1 is the limit displacement.

[0031] Specifically, in S30:

[0032] The calculation model for the total axial stiffness of the bolts between the guide rail and the anvil is as follows: In the formula, k b n is the total axial stiffness of the bolts between the guide rail and the anvil. b Let E be the number of bolts between the rail and the anvil, E be the elastic modulus of the bolt material between the rail and the anvil, A be the minimum cross-sectional area of ​​the bolt between the rail and the anvil, and l be the working length of the bolt between the rail and the anvil.

[0033] The calculation model for flange stiffness is as follows: In the formula, k s φ represents the flange stiffness, and φ represents the relative stiffness.

[0034] Specifically, in S30, when the anvil moves upward, and the displacement is 0 to δ, the connection stiffness between the liner and the anvil is set to k. b +k sWhen the displacement is greater than δ, the connection stiffness k3 between the liner and the anvil is set to k b ;

[0035] When the anvil moves downward, the connection stiffness k3 between the liner and the anvil is set to k. b +k s δ represents the displacement of the flange before separation under critical load.

[0036] Specifically, in S40, the calculation model for the mass of the supporting channel steel is as follows: In the formula, m4 represents the mass of the supporting channel steel involved, and m a Let L be the modal mass of a single supporting channel steel, L be the total length of the simply supported channel steel, a be the span of the tested equipment, and n be the number of supporting channel steels.

[0037] Specifically, in S40, the calculation model for the warping damping of the supporting channel steel is as follows: In the formula, c4 is the warping damping of the supporting channel steel, m5 is the mass of the tested equipment, and k w k is the stiffness of the supporting channel steel when the channel steel warps. s This refers to the stiffness of the supporting channel steel when the channel steel is bent concave.

[0038] Specifically, S60 includes the following steps:

[0039] In Abaqus, 6 reference points are established vertically from bottom to top along the coordinate axis, and 5 MASS elements are established at the 2nd to 6th reference points from bottom to top. The real constants of the 5 MASS elements are, in order, the mass of the concrete foundation, the mass of the anvil, the mass of the liner, the mass of the supporting channel steel, and the mass of the tested equipment.

[0040] In the five MASS elements, a BUSHING element is established between every two mass elements. The stiffness parameters of each BUSHING element are, in order, the stiffness of the helical spring around the concrete base, the stiffness of the anvil guide bolt, the connection stiffness between the liner and the anvil, the stiffness of the support channel steel, and the connection stiffness of the mass of the tested equipment.

[0041] Among them, the damping of the second BUSHING unit is the anvil guide bolt fall-back damping, the damping of the fourth BUSHING unit is the support channel steel warping damping, and the unit damping of the fifth BUSHING is the support channel steel warping damping.

[0042] Full constraints are applied to the first reference point, and longitudinal and lateral constraints are applied to the second to sixth reference points to form a multi-free dynamic model of the pendulum impact machine.

[0043] The present invention has the following advantages and beneficial effects:

[0044] 1. The method for establishing a digital model of a pendulum impact tester provided by this invention first obtains the stiffness of the helical springs around the concrete base, the stiffness of the anvil's upward movement, the stiffness and damping of the anvil's fall, the connection stiffness between the liner and the anvil, the mass of the supporting channel steel, the warping damping of the supporting channel steel, and the connection stiffness and motion damping between the tested equipment and the pendulum impact tester. Then, in finite element analysis software, based on the mass of the concrete foundation, the mass of the anvil, the mass of the liner, the mass of the supporting channel steel, the mass of the tested equipment, the stiffness of the helical springs around the concrete base, the stiffness of the anvil guide bolts, the connection stiffness between the liner and the anvil, the stiffness of the supporting channel steel, the connection stiffness of the tested equipment mass, the fall damping of the anvil guide bolts, the warping damping of the supporting channel steel, and the motion damping of the tested equipment, a multi-free dynamic model of the pendulum impact tester is established. This establishes a digital model of the pendulum impact tester, which can replace the real impact tester for equipment impact assessment tests. This solves the problems of the current limited number of pendulum impact testers, high testing costs, and long testing times, greatly improving the balance between testing efficiency and project progress.

[0045] 2. The pendulum impact machine model established in this invention is a digital model, which can avoid large-scale mesh and computational workload, and make up for the shortcomings of existing numerical models that cannot accurately simulate the impact machine action process. It can quickly and accurately complete the virtual test of equipment impact assessment and obtain the impact assessment environment.

[0046] 3. The method for establishing a digital model of a pendulum impactor provided by this invention involves fewer parameters and has high accuracy, and can be applied to the establishment of numerical models for all pendulum impactors. Attached Figure Description

[0047] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope.

[0048] In the attached diagram:

[0049] Figure 1 This is a flowchart illustrating the method for establishing a digital model of a pendulum impact machine according to an embodiment of the present invention.

[0050] Figure 2 This is a schematic diagram of the pendulum impact machine with multiple degrees of freedom according to an embodiment of the present invention;

[0051] Figure 3 A digital model of a pendulum-type medium-sized impact machine was established for an embodiment of the present invention. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0053] Example

[0054] Combination Figure 1 This embodiment provides a method for establishing a digital model of a pendulum impact machine, including the following steps:

[0055] S10. Based on the sum of the mass of the concrete foundation and the mass of the impactor base during the construction of the pendulum impactor, as well as the first-order installation frequency of the impactor base, the stiffness of the helical springs around the concrete base is calculated.

[0056] Specifically, the calculation model for the stiffness of the helical springs around the concrete base is k1=(2πf1). 2 ·m1;

[0057] In the formula:

[0058] f1 is the first-order natural installation frequency of the impact machine base.

[0059] m1 represents the mass of the concrete foundation.

[0060] k1 represents the stiffness of the helical springs surrounding the concrete base.

[0061] S20. Based on the axial stiffness of the single guide bolt between the anvil and the base of the pendulum impact machine and the number of bolts, calculate the stiffness of the anvil moving upward, and based on the buffer stiffness and damping of the pendulum impact machine, calculate the stiffness and damping of the anvil falling back.

[0062] Specifically, the calculation model for the axial stiffness of a single guide bolt is as follows: In the formula, E is the elastic modulus of the guide bolt material, A is the minimum cross-sectional area of ​​the guide bolt, and l is the working length of the guide bolt;

[0063] The stiffness calculation model for the upward motion of the anvil is k. up =n 轴 ·k 轴 In the formula, n 轴 k represents the number of guide bolts. up The stiffness of the anvil during its upward movement;

[0064] The calculation model for the damping of the anvil's fall is as follows: In the formula, c2 is the damping of the anvil guide bolt falling back, ξ is the damping coefficient (generally taken as 0.02~0.03), and k 缓冲 For the stiffness of the buffer spring inside the hydraulic cylinder of the pendulum impact machine, n 缓冲m2 represents the number of buffer springs inside the hydraulic cylinder of the pendulum impact machine, and m2 represents the mass of the anvil of the pendulum impact machine.

[0065] It should be noted that when the anvil moves upward, the stiffness k2 of the anvil guide bolt is set to 0 when the displacement is between 0 and L1, and to k when the displacement is greater than L1. up ;

[0066] When the anvil moves downwards, the stiffness k2 of the anvil guide bolt is set to k. down ;

[0067] Where L1 is the limit displacement.

[0068] S30. Calculate the connection stiffness between the rail and the anvil based on the total axial stiffness of the bolts and the flange stiffness between the rail and the anvil.

[0069] Specifically, the calculation model for the total axial stiffness of the bolts between the liner and the anvil is as follows: In the formula, k b n is the total axial stiffness of the bolts between the guide rail and the anvil. b Let E be the number of bolts between the rail and the anvil, E be the elastic modulus of the bolt material between the rail and the anvil, A be the minimum cross-sectional area of ​​the bolt between the rail and the anvil, and l be the working length of the bolt between the rail and the anvil.

[0070] The calculation model for flange stiffness is as follows: or In the formula, k s φ represents the flange stiffness, and φ represents the relative stiffness.

[0071] When the anvil moves upward, and the displacement is 0 to δ, the connection stiffness between the guide rail and the anvil is set to k. b +k s When the displacement is greater than δ, the connection stiffness k3 between the liner and the anvil is set to k b ;

[0072] When the anvil moves downward, the connection stiffness k3 between the liner and the anvil is set to k. b +k s .

[0073] Where δ represents the displacement of the flange before separation under critical load, and its calculation model is as follows: In the formula F a This is the critical load when the flange separates.

[0074] The calculation model for the critical load during flange separation is as follows: In the formula, F0 is the preload of the flange bolts.

[0075] S40. Based on the modal mass of a single support channel steel under simply supported constraints at both ends, determine the mass involved in the support channel steel and calculate the warping damping of the support channel steel.

[0076] Specifically:

[0077] The calculation model for the mass of the supporting channel steel is as follows: In the formula, m4 represents the mass of the supporting channel steel involved, and m a Let L be the modal mass of a single supporting channel steel, L be the total length of the simply supported channel steel, a be the span of the tested equipment, and n be the number of supporting channel steels.

[0078] The calculation model for the warping damping of the supporting channel steel is as follows: In the formula, c4 is the warping damping of the supporting channel steel, m5 is the mass of the tested equipment, and k w k is the stiffness of the supporting channel steel when the channel steel warps. s This refers to the stiffness of the supporting channel steel when the channel steel is bent concave.

[0079] To determine the stiffness of the supporting channel steel during channel steel warping, a calculation model is used. and The calculation yields k', where k' is the most common component in the formula. w k' is the test value of the warping stiffness of the channel steel. s f is the experimental value of the concave bending stiffness of the channel steel. f The results were obtained from the calibration test, where n' is the number of supporting channel steels in the calibration test.

[0080] Among them, the stiffness of the supporting channel steel when the channel steel is concave is The calculation yields the result, where k”. s t is the theoretical value of the concave bending stiffness of the channel steel, t is the distance between the equipment installation position and the fixed position of the supporting channel steel, L is the total simply supported length of the supporting channel steel, E is the elastic modulus of the supporting channel steel material, and I is the moment of inertia of the supporting channel steel.

[0081] S50. Determine the connection stiffness and action damping between the tested equipment and the pendulum impact machine based on the mass of the tested equipment, the actual installation method, and the operating frequency.

[0082] Among them, the mass of the tested equipment is m5, the connection stiffness after considering the installation method, installation frequency and equipment mass of the tested equipment is k5, and the action damping of the tested equipment is c5.

[0083] S60. Based on the mass of the concrete foundation, the mass of the anvil, the mass of the liner rail, the mass of the supporting channel steel, the mass of the tested equipment, the stiffness of the helical springs around the concrete base, the stiffness of the anvil guide bolts, the connection stiffness between the liner rail and the anvil, the stiffness of the supporting channel steel, the connection stiffness of the tested equipment mass, the fallback damping of the anvil guide bolts, the warping damping of the supporting channel steel, and the motion damping of the tested equipment, a multi-free dynamic model of the pendulum impact machine is established in the finite element analysis software.

[0084] Combination Figure 2 and 3 Specifically, in Abaqus (a commercial software for display dynamics calculation), six reference points (RP1 to RP6) are established vertically along the coordinate axis from bottom to top, and five MASS elements (MASS1 to MASS5) are established at the second to sixth reference points (RP2 to RP6) from bottom to top. The real constants of the five MASS elements are, in order, the mass of the concrete foundation, the mass of the anvil, the mass of the rail liner, the mass of the supporting channel steel, and the mass of the tested equipment. That is, the real constants of MASS1 to MASS5 are m1 to m5 respectively.

[0085] In the five MASS elements (MASS1-MASS5), a BUSHING element (BUSHING1-BUSHING5) is established between every two mass elements. The stiffness parameters of each BUSHING element are, in order, the stiffness of the helical spring around the concrete base, the stiffness of the anvil guide bolt, the connection stiffness between the liner and the anvil, the stiffness of the support channel steel, and the connection stiffness of the mass of the tested equipment, i.e., BUSHING1-BUSHING5, with stiffness parameters taken as k1 to k5 respectively.

[0086] Among them, the damping of the second BUSHING unit (BUSHING2) is the anvil guide bolt fall-back damping (c2), the damping of the fourth BUSHING unit (BUSHING4) is the support channel steel warping damping (c4), and the damping of the fifth BUSHING unit (BUSHING5) is the support channel steel warping damping (c5).

[0087] Full constraints are applied to the first reference point (RP1), and longitudinal and lateral constraints are applied to the second to sixth reference points (RP2 to RP5). That is, all degrees of freedom except vertical are constrained for RP2 to RP5 to form a multi-free dynamic model of the pendulum impact machine.

[0088] In summary, the method for establishing a digital model of the pendulum impact machine provided in this embodiment first obtains the stiffness of the helical springs around the concrete base, the stiffness of the anvil's upward movement, the stiffness and damping of the anvil's fall, the connection stiffness between the liner and the anvil, the mass of the supporting channel steel, the warping damping of the supporting channel steel, and the connection stiffness and motion damping between the tested equipment and the pendulum impact machine. Then, in the finite element analysis software, based on the mass of the concrete base, the mass of the anvil, the mass of the liner, the mass of the supporting channel steel, the mass of the tested equipment, the stiffness of the helical springs around the concrete base, the stiffness of the anvil guide bolts, the connection stiffness between the liner and the anvil, the stiffness of the supporting channel steel, the connection stiffness of the tested equipment mass, the fall damping of the anvil guide bolts, the warping damping of the supporting channel steel, and the motion damping of the tested equipment, a multi-free dynamic model of the pendulum impact machine is established, thereby establishing a digital model of the pendulum impact machine. Therefore, it can replace the actual impact tester for equipment impact assessment, thereby solving the problems of the current limited number of pendulum impact testers, high testing costs, and long testing time, and greatly improving the contradiction between testing efficiency and project progress.

[0089] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for establishing a digital model of a pendulum impact machine, characterized in that, Includes the following steps: S10. Based on the sum of the concrete foundation mass and the mass of the impactor base during the construction of the pendulum impactor, as well as the first-order installation frequency of the impactor base, the stiffness of the helical springs around the concrete base is calculated. S20. Based on the axial stiffness of the single guide bolt between the anvil and the base of the pendulum impact machine and the number of bolts, calculate the stiffness of the anvil moving upward, and based on the buffer stiffness and damping of the pendulum impact machine, calculate the stiffness and damping of the anvil falling back. S30. Calculate the connection stiffness between the rail and the anvil based on the total axial stiffness of the bolts and the flange stiffness between the rail and the anvil. S40. Based on the modal mass of a single support channel steel under simply supported constraints at both ends, determine the mass involved in the support channel steel and calculate the warping damping of the support channel steel. S50. Determine the connection stiffness and action damping between the tested equipment and the pendulum impact machine based on the mass of the tested equipment, the actual installation method, and the operating frequency. S60. Based on the mass of the concrete foundation, the mass of the anvil, the mass of the liner rail, the mass of the supporting channel steel, the mass of the tested equipment, the stiffness of the helical springs around the concrete base, the stiffness of the anvil guide bolts, the connection stiffness between the liner rail and the anvil, the stiffness of the supporting channel steel, the connection stiffness of the tested equipment mass, the fallback damping of the anvil guide bolts, the warping damping of the supporting channel steel, and the motion damping of the tested equipment, a multi-free dynamic model of the pendulum impact machine is established in the finite element analysis software.

2. The method for establishing a digital model of a pendulum impact machine according to claim 1, characterized in that, In S10, the calculation model for the stiffness of the helical springs around the concrete base is k1=(2πf1). 2 ·m1; In the formula: f1 is the first-order natural installation frequency of the impact machine base. m1 represents the mass of the concrete foundation. k1 represents the stiffness of the helical springs surrounding the concrete base.

3. The method for establishing a digital model of a pendulum impact machine according to claim 1, characterized in that, In S20: The calculation model for the axial stiffness of a single guide bolt is as follows: In the formula, E is the elastic modulus of the guide bolt material, A is the minimum cross-sectional area of ​​the guide bolt, and l is the working length of the guide bolt; The stiffness calculation model for the upward motion of the anvil is k. up =n 轴 ·k 轴 In the formula, n 轴 k represents the number of guide bolts. up Let be the stiffness of the anvil as it moves upward.

4. The method for establishing a digital model of a pendulum impact machine according to claim 3, characterized in that, In S20, the calculation model for the anvil's fall damping is as follows: In the formula, c2 is the damping of the guide bolt falling back, ξ is the damping coefficient, and k 缓冲 For the stiffness of the buffer spring inside the hydraulic cylinder of the pendulum impact machine, n 缓冲 m2 represents the number of buffer springs inside the hydraulic cylinder of the pendulum impact machine, and m2 represents the mass of the anvil of the pendulum impact machine.

5. The method for establishing a digital model of a pendulum impact machine according to claim 3, characterized in that, When the anvil moves upward, the stiffness k2 of the anvil guide bolt is set to 0 when the displacement is between 0 and L1, and to k when the displacement is greater than L1. up ; When the anvil moves downwards, the stiffness k2 of the anvil guide bolt is set to k. down ; Where L1 is the limit displacement.

6. The method for establishing a digital model of a pendulum impact machine according to claim 1, characterized in that, In S30: The calculation model for the total axial stiffness of the bolts between the guide rail and the anvil is as follows: In the formula, k b n is the total axial stiffness of the bolts between the guide rail and the anvil. b Let E be the number of bolts between the rail and the anvil, E be the elastic modulus of the bolt material between the rail and the anvil, A be the minimum cross-sectional area of ​​the bolt between the rail and the anvil, and l be the working length of the bolt between the rail and the anvil. The calculation model for flange stiffness is as follows: In the formula, k s φ represents the flange stiffness, and φ represents the relative stiffness.

7. The method for establishing a digital model of a pendulum impact machine according to claim 6, characterized in that, In S30, when the anvil moves upward, and the displacement is 0 to δ, the connection stiffness between the liner and the anvil is set to k. b +k s When the displacement is greater than δ, the connection stiffness k3 between the liner and the anvil is set to k b ; When the anvil moves downward, the connection stiffness k3 between the liner and the anvil is set to k. b +k s ; Where δ is the displacement of the flange before separation under critical load.

8. The method for establishing a digital model of a pendulum impact machine according to claim 1, characterized in that, In S40, the calculation model for the mass of the supporting channel steel is as follows: In the formula, m4 represents the mass of the supporting channel steel involved, and m a Let L be the modal mass of a single supporting channel steel, L be the total length of the simply supported channel steel, a be the span of the tested equipment, and n be the number of supporting channel steels.

9. The method for establishing a digital model of a pendulum impact machine according to claim 8, characterized in that, In S40, the calculation model for the warping damping of the supporting channel steel is as follows: In the formula, c4 is the warping damping of the supporting channel steel, m5 is the mass of the tested equipment, and k w k is the stiffness of the supporting channel steel when the channel steel warps. s This refers to the stiffness of the supporting channel steel when the channel steel is bent concave.

10. The method for establishing a digital model of a pendulum impact machine according to claim 1, characterized in that, S60 includes the following steps: In Abaqus, 6 reference points are established vertically from bottom to top along the coordinate axis, and 5 MASS elements are established at the 2nd to 6th reference points from bottom to top. The real constants of the 5 MASS elements are, in order, the mass of the concrete foundation, the mass of the anvil, the mass of the liner, the mass of the supporting channel steel, and the mass of the tested equipment. In the five MASS elements, a BUSHING element is established between every two mass elements. The stiffness parameters of each BUSHING element are, in order, the stiffness of the helical spring around the concrete base, the stiffness of the anvil guide bolt, the connection stiffness between the liner and the anvil, the stiffness of the support channel steel, and the connection stiffness of the mass of the tested equipment. Among them, the damping of the second BUSHING unit is the anvil guide bolt fall-back damping, the damping of the fourth BUSHING unit is the support channel steel warping damping, and the damping of the fifth BUSHING unit is the support channel steel warping damping. Full constraints are applied to the first reference point, and longitudinal and lateral constraints are applied to the second to sixth reference points to form a multi-free dynamic model of the pendulum impact machine.

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