CN-121997487-A - Topology optimization buckling restrained structure design method and system for hollow variable-section plunger rod

CN121997487ACN 121997487 ACN121997487 ACN 121997487ACN-121997487-A

Abstract

The invention relates to the technical field of topology optimization, in particular to a method and a system for designing a topology optimization buckling restrained structure of a hollow variable-section plunger rod. The method comprises the steps of obtaining telescopic data of a plunger rod, determining the maximum movable stroke based on the telescopic data, judging the buckling hazard degree by utilizing the maximum movable stroke, detecting the moment of inertia distribution of a variable cross section according to the buckling hazard degree, evaluating the stability of a plunger rod of the plunger rod by utilizing the moment of inertia distribution, designing an anti-buckling structure according to the stability of the plunger rod and the buckling hazard degree, simulating buckling limit load based on the anti-buckling structure, detecting the material breaking strength under the buckling limit load, detecting groove surface cracks by utilizing the material breaking strength, marking the groove surface crack positions, and carrying out multistage material strengthening treatment on the groove surface crack positions to generate multistage material data. The invention improves the buckling stability and the service life of the plunger rod based on the topology optimization technology, and improves the safety and the reliability of the structure.

Inventors

XU DEXIN
WU DEXIN
MA RENCHAO
CAO HUIYING
XU WENBING
YU JUNYANG
CHEN QI
CUI ZHI
ZHANG WENKE
YANG WEIHUA
LI ZHIXING
LI ZICHONG

Assignees

中国电建集团昆明勘测设计研究院有限公司
华能澜沧江水电股份有限公司
三峡大学

Dates

Publication Date: 20260508
Application Date: 20251231

Claims (10)

1. The topological optimization buckling restrained structure design method of the hollow variable-section plunger rod is applied to a plunger type hydraulic hoist and is characterized by comprising the following steps of: Step S1, acquiring telescopic data of a plunger rod, determining a maximum movable stroke based on the telescopic data, and judging the buckling hazard degree by utilizing the maximum movable stroke; s2, detecting moment of inertia distribution of a variable cross section according to the buckling hazard degree, evaluating the stability of a pressing rod of the plunger rod by utilizing the moment of inertia distribution, and designing an anti-buckling structure according to the stability of the pressing rod and the buckling hazard degree; s3, simulating a buckling limit load based on the buckling restrained structure, and detecting the breaking strength of the material under the buckling limit load; and S4, carrying out multistage material strengthening treatment on the crack position of the groove surface to generate multistage material data, and designing a four-bar jacking structure based on the multistage material data.
2. The method for designing a topologically optimized buckling restrained structure of a hollow variable cross-section plunger rod according to claim 1, wherein step S1 is specifically: step S11, obtaining telescopic data of a plunger rod; step S12, recording a start coordinate and a stop coordinate by using the telescopic data; step S13, calculating the maximum movable travel according to the initial coordinate and the final coordinate; And S14, extracting the effective length of the plunger rod by utilizing the maximum movable stroke, determining the interface sectional area of the plunger rod, calculating the slenderness ratio according to the effective length and the interface sectional area, and judging the buckling hazard degree.
3. The method for designing a topologically optimized buckling restrained structure of a hollow variable cross-section plunger rod according to claim 1, wherein step S2 is specifically: s21, identifying a high-risk area according to the buckling risk degree, and calculating the diameter of a plunger rod in the high-risk area; s22, determining moment of inertia mutation points based on moment of inertia distribution; s23, acquiring actual load of a moment of inertia abrupt change point, and evaluating the stability of a compression bar by utilizing the actual load and a preset buckling safety coefficient; And S24, designing the buckling restrained structure according to the stability of the compression bar and the buckling danger degree.
4. The method for designing a topologically optimized buckling restrained structure of a hollow variable cross-section plunger rod according to claim 3, wherein step S24 is specifically: S241, recognizing an unstable region by utilizing the stability of a compression bar, and additionally installing a cylindrical steel sleeve in the unstable region; Step S242, according to the buckling hazard degree, embedding a limiting ring into the buckling hazard plunger rod section, and designing a copper-based sliding sleeve; and step S243, fixing the copper-based sliding sleeve at the mounting groove of the additionally-installed cylindrical steel sleeve to form the buckling restrained structure.
5. The method for designing a topologically optimized buckling restrained structure of a hollow variable cross-section plunger rod according to claim 1, wherein step S3 is specifically: s31, performing axial compression simulation based on the buckling restrained structure to determine buckling limit load; S32, calculating the maximum equivalent stress of the material under the condition of buckling limit load; S33, identifying a stress concentration position according to the maximum equivalent stress of the material; step S34, detecting the breaking strength of the material at the stress concentration position; and S35, detecting groove surface cracks by using the breaking strength of the material, and marking the positions of the groove surface cracks.
6. The method for designing a topologically optimized buckling restrained structure of a hollow variable cross-section plunger rod according to claim 5, wherein step S35 is specifically: S351, calibrating a high fracture strength area by using the fracture strength of the material, and identifying an axial crack; Step S352, detecting the edge sharpness of the axial crack and identifying the fatigue crack; Step S353, detecting fracture grains at the positions of fatigue cracks, and judging brittle fracture if the fracture grains are obviously reflected and bright; Step S354, recognizing fracture morphology at the position of fatigue crack, and judging that the fracture is ductile if the fracture is ductile fossa; and step S355, marking the crack position of the groove surface where the brittle fracture and the ductile fracture are located.
7. The method for designing a topologically optimized buckling restrained structure of a hollow variable cross-section plunger rod according to claim 1, wherein step S4 is specifically: Step S41, determining shot blasting grain size at the groove surface crack position, and performing a shot blasting process to form a compressive stress layer, wherein the hardness of the compressive stress layer is improved, the adhesive force of the surface coating is improved, and the surface coating data are obtained; S42, carrying out subsurface strengthening on the crack position of the groove surface to obtain subsurface data; step S43, fusing the surface coating data and the subsurface data to obtain multi-level material data; And S44, designing a four-bar jacking structure based on the multi-level material data.
8. The method for designing a topologically optimized buckling restrained structure of a hollow variable cross-section plunger rod according to claim 7, wherein step S42 is specifically: s421, determining a subsurface strengthening range at the crack position of the groove surface; Step S422, quenching is carried out in the strengthening range of the subsurface layer to form a high-strength martensitic layer; Step S423, performing microstructure analysis on the high-strength martensitic layer, and verifying the uniformity of the martensitic layer; and S424, controlling the quenched heat affected zone, and ensuring a smooth transition zone of the high-strength martensitic layer so as to obtain subsurface layer data.
9. The method for designing a topologically optimized buckling restrained structure of a hollow variable cross-section plunger rod according to claim 7, wherein step S44 specifically comprises: step S441, performing stress load simulation based on multi-level material data, and identifying a stress concentration area; Step S442, determining the installation area of the four jacking rods according to the stress concentration area; S443, designing and arranging a reinforced steel plate in the installation area of the four jacking rods, and reserving installation bolt hole sites so as to obtain reinforced installation structure design data; And S444, planning the relative position relation between the jacking rods and the platform guide rail according to the reinforced mounting structure design data, and adjusting the spacing between the four jacking rods so as to obtain the four-bar jacking structure.
10. A topology-optimized buckling restrained structure design system of a hollow variable-section plunger rod, characterized by performing the topology-optimized buckling restrained structure design method of a hollow variable-section plunger rod according to claim 1, comprising: the buckling danger judging module is used for acquiring the telescopic data of the plunger rod, determining the maximum movable travel based on the telescopic data, and judging the buckling danger degree by utilizing the maximum movable travel; The buckling restrained structure design module is used for detecting moment of inertia distribution of the variable cross section according to buckling hazard degree, evaluating the stability of a pressing rod of the plunger rod by utilizing the moment of inertia distribution, and designing the buckling restrained structure according to the stability of the pressing rod and the buckling hazard degree; The groove surface crack detection module is used for simulating buckling limit load based on the buckling-restrained structure, detecting the material fracture strength under the buckling limit load, detecting the groove surface crack by using the material fracture strength, and marking the position of the groove surface crack; The multi-stage material strengthening module is used for carrying out multi-stage material strengthening treatment on the crack position of the groove surface to generate multi-stage material data, and the four-bar jacking structure is designed based on the multi-stage material data.

Description

Topology optimization buckling restrained structure design method and system for hollow variable-section plunger rod Technical Field The invention relates to the technical field of topology optimization, in particular to a method and a system for designing a topology optimization buckling restrained structure of a hollow variable-section plunger rod. Background At present, the plunger type hydraulic hoist is widely applied to the hoist operation of hydraulic construction, lock gates and large-scale mechanical equipment, but under the conditions of long travel and large load, the plunger rod is easy to have the problems of buckling deformation, fatigue crack, material failure and the like, and the operation safety and the service life are influenced. In the prior art, structural optimization of the plunger rod is mainly focused on increasing the cross section size or adopting high-strength materials to improve the overall rigidity, but the method can obviously increase the mass of the plunger rod, so that the manufacturing cost is increased, the processing difficulty is increased, and higher requirements are put forward on a driving system of the hoist. The traditional buckling-restrained design is in a uniform cross section mode, stress differences of different areas are difficult to consider, the material utilization rate is low, the local strength is insufficient easily, and in the aspect of fatigue crack treatment, the existing method is often stopped on surface repair or single material reinforcement, and cracks can not be effectively prevented from continuously expanding on the subsurface layer or inside, so that the cracks repeatedly appear. For a large-scale opening and closing mechanism with multipoint jacking, the existing two-bar or double-cylinder jacking scheme has certain limitation in terms of synchronism and structural stability, and particularly, the bearing capacity of the large-scale opening and closing mechanism cannot be fully exerted when the large-scale opening and closing mechanism is matched with a complex working condition and a local reinforced structure after multi-stage material treatment. Disclosure of Invention Based on this, the present invention needs to provide a method and a system for designing a topologically optimized buckling restrained structure of a hollow variable-section plunger rod, so as to solve at least one of the above technical problems. In order to achieve the above purpose, a topology optimization buckling restrained structure design method of a hollow variable-section plunger rod comprises the following steps: Step S1, acquiring telescopic data of a plunger rod, determining a maximum movable stroke based on the telescopic data, and judging the buckling hazard degree by utilizing the maximum movable stroke; s2, detecting moment of inertia distribution of a variable cross section according to the buckling hazard degree, evaluating the stability of a pressing rod of the plunger rod by utilizing the moment of inertia distribution, and designing an anti-buckling structure according to the stability of the pressing rod and the buckling hazard degree; s3, simulating a buckling limit load based on the buckling restrained structure, and detecting the breaking strength of the material under the buckling limit load; and S4, carrying out multistage material strengthening treatment on the crack position of the groove surface to generate multistage material data, and designing a four-bar jacking structure based on the multistage material data. The invention has the following beneficial effects: according to the first aspect, through maximum movable stroke calculation and buckling danger degree judgment based on telescopic data, the high-risk stress area of the plunger rod can be accurately identified according to different working conditions. By combining the moment of inertia distribution analysis of the variable cross section, the material waste caused by global thickening in the traditional design is effectively avoided, so that the plunger rod can remarkably reduce the quality and the manufacturing cost and improve the material utilization rate while meeting the buckling resistance requirement. In the second aspect, structural reinforcement can be realized in a local stress unstable area by utilizing moment of inertia abrupt point load detection and compression bar stability evaluation and combining the cooperative design of a cylindrical steel sleeve, a limiting ring and a copper-based sliding sleeve. The method greatly improves the local rigidity and the buckling critical load on the premise of not remarkably increasing the whole volume, and effectively prevents early buckling instability. In the third aspect, multistage material strengthening treatment is carried out on the crack position of the groove surface, a compressive stress layer is formed on the surface layer by adopting shot blasting, the adhesive force of a surface coating is improved, a high-strengthen