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To ensure that the frame of the large upsetting ratio hydraulic press can perform its functions reliably under load, this paper conducts an in-depth analysis of the main load-bearing component, the upper beam of the hydraulic press frame. First, the frame structure is designed; then, the preload and stress characteristics of the designed frame are analyzed. Finally, a strength analysis is carried out using finite element simulation software. The results indicate that the designed upper beam of the large upsetting ratio hydraulic press frame meets the required working strength.

Aiming at the problems of traditional exoskeletons, such as high weight, short use time and long charging time, a lower extremity load-carrying exoskeleton with an energy storage element is proposed. The exoskeleton is 5 kg weight and composed of a main body frame and an energy storage element. Through analyzing the exoskeleton and human body, the energy storage element is designed as a variable stiffness spring with a pre-tightening load, and the spring stiffness is optimized using a step-by-step search method. Finally, the correctness of the mathematical model is verified by simulating the dynamics of ADAMS. Under 40 kg weight-bearing, the simulation results show that the unilateral exoskeleton can transfer 60% of the load weight to the ground, reducing 11.9% of all the effective torque of humans.

A typical one-degree-of-freedom (1DOF) shock isolator that has quasi-zero stiffness (QZS) characteristics consists of two transversal springs and one portrait spring. The transversal springs can provide negative stiffness and the vertical spring is used as a load-bearing component. In this article, an improved 1DOF QZS shock isolator is obtained by utilizing the combination of lateral bars and springs. The displacement transmissibility under the harmonic excitation is obtained and the principle of minimum displacement transmissibility under the condition of system stability is proposed. Finally, numerical simulation is conducted, and the simulation results reflect that the proposed 1DOF QZS isolator significantly performs better than the previous one.

The all-steel spiral anchor demonstrates exceptional advantages in terms of construction convenience and rapid deployment. To validate its Application in transmission engineering, an extensive field study was conducted to investigate the influence of inclination angle, buried depth, and anchor specifications on its load-bearing performance. The findings reveal that the load-bearing capacity of an individual anchor foundation is significantly influenced by these factors. Specifically, with a constant anchor rod burial length, an increase in the inclination angle leads to a relative decrease in the soil-embedded depth of the spiral anchor, thereby reducing its pull-out resistance. Furthermore, a direct correlation is evident between the pull-out resistance of spiral anchors and their embedment depth. Notably, changes in buried depth have minimal impact in the early stages of loading. However, as the load progressively increases, the force exerted on the anchor plate significantly escalates with displacement, resulting in a growing influence of embedment depth on the anchor’s load-bearing capacity. Enhancing the size and number of anchor components has been observed to have a favorable effect on the overall load-bearing capability of the anchor system. As displacement increases, upward displacement of the anchor plate compresses the surrounding soil, making the anchor plate’s contribution more pronounced and eventually surpassing that of the anchor rod.

The ball-and-socket joint, serving as the load-bearing component of the ball-and-socket nozzle, primarily consists of a ball and a socket, both manufactured from carbon/carbon woven composite materials. Under inlet pressure, to ensure sufficient strength and sealing performance during joint oscillation, lesser contact stress and moderate contact deformation must occur between the ball and socket contact surfaces. The stresses and deformations within this joint under complex loading conditions constitute a nonlinear contact boundary problem, whose solution depends on load history and is difficult to solve analytically. To address this, the nonlinear finite element numerical calculation model for the ball-and-socket friction contact within the joint was established. This model can compute and analyze the contact stress and deformation distribution between the ball and socket under different inlet pressures, providing preliminary validation for the joint’s contact load-bearing performance.

Forklift AGV is a widely used intelligent warehousing and logistics equipment, and is one of the key equipment for promoting the construction of intelligent workshops and factories. As one of the key load-bearing components of a forklift-type AGV, the fork frame affects its working ability. This article analyzes the structure and stress situation of a forklift-type AGV fork frame, obtains the force diagram and dangerous section of the fork frame, and verifies the strength of the dangerous section according to classical mechanical methods. At the same time, a three-dimensional model of the fork frame was established and subjected to static analysis by using Ansys Workbench software. The results showed that the theoretical calculation results were consistent with the simulation analysis results, verifying the correctness of the calculation results. In addition, the structure was optimized with quality objectives, reducing the weight of the fork by 11.5%. Simulation analysis was conducted again on the optimized fork, and the results showed that the fork structure design can meet the requirements for use.

In this work, the effect of processing parameters on the resulting microstructure and mechanical properties of magnesium alloy WE43 processed via Additive Friction Stir Deposition (AFSD), a nascent solid-state additive manufacturing (AM) process, is investigated. In particular, a parameterization study was carried out, using multiple four-layer deposits, to identify a suitable process window for a structural 68-layers bulk WE43 deposition. The parametric study identified an acceptable set of parameters with minimal surface defects and excellent consolidation for the fabrication of a bulk WE43 deposition. Microstructural, tensile, and fatigue life characterization was conducted on the bulk WE43 deposition and compared to commercially available wrought material to elucidate the process-structure-property-performance (PSPP) relationship of the AFSD process. This study shows that the bulk WE43 deposit exhibited a refined homogenous microstructure and a texture shift relative to the wrought material. However, a reduction in hardness and tensile behavior was observed in the as-deposited WE43 compared to the wrought control. Additionally, fatigue specimens extracted from the bulk deposition exhibited a decrease in life in the low-cycle regime but performed comparably to the wrought plate in the high-cycle regime. The outcomes of this study illustrate the potential of the AFSD process in additively manufactured structural load-bearing components made with magnesium alloy WE43 in the as-built condition.

This work introduces a novel approach for characterizing the residual load bearing capacity of fractured components based on the Phase Field fracture model. The underlying idea involves exploiting this well-established framework for fracturing materials and applying it to mechanically loaded domains in which fracture has already occurred. Hence, the continuous phase field here portrays the smeared representation of known crack patterns, based on which the unilateral contact interactions between the crack lips are enforced through a suitable strain energy decomposition. This allows for a theoretically robust and implicit treatment of the originally discontinuous problem while remaining in a continuum framework. As such, the proposed approach avoids the numerically challenging definition and management of conventional contact pairs, thus proving to be especially promising for its application to domains with multiple fragments. Besides presenting the theoretical foundation and algorithmic convenience of the approach, its accuracy and representativeness are proven against theoretical predictions and numerical results from Finite Element models featuring conventional contact interactions.

With advancements in aerospace engineering design, grid-stiffened shells, vital load-bearing components of aerospace structures, are increasingly required to conform to curved shapes and features, such as cutouts. However, traditional design methods often struggle to meet these evolving requirements. The current study introduces a generative design method for the grid-stiffened curved shells. Initially, the stiffener layout is optimized using an equivalent model based on the homogenization method. Following this optimization, a stiffener control field is constructed, allowing for the detailed description of dense, non-uniform grid stiffeners without the need for additional variables. Building on this model, a refined model of grid-stiffened curved shells is obtained through parametric optimization. A curved surface composed of piecewise polynomials and its variant with cutouts, as well as a cylindrical-like shell composed of non-uniform rational basis spline (NURBS) curves, illustrate the effectiveness of the method. Results indicate that the proposed method increases the critical buckling loads of the two structures by 17.42%, 17.28%, and 15.92%, respectively, compared to optimized traditional orthogonal grid stiffening. These findings underscore the effectiveness of the method in generating innovative designs for grid-stiffened curved shells featuring distinct stiffener paths, enhanced performance, and direct applicability for detailed modeling.

Mechanical components are often subjected to time-varied loading during their service. One of the key objectives for designing these parts is to reduce the weight while maintaining the load-bearing capacity. To this end, we propose a second-order cone programming (SOCP) based technique that allows the topology of elastoplastic structures to be optimized with respect to the shakedown limit. The method established consists of nested loops, in the inner loop the shakedown limit is calculated by solving a SOCP problem formulated according to Melan’s theorem, while in the outer loop, the topology optimization is realized by a gradient-based algorithm in which the sensitivity of each element is evaluated using solutions of the shakedown problem as inputs. To enhance the numerical efficiency, inequality constraints in the shakedown problem are converted to Euclidean ball constraints, while a slack variable-based tactic is employed to facilitate the sensitivity calculation. Applying the method to two classical examples and a 3D spacecraft bracket emerged from engineering practice, the capability of the method in dealing with real engineering structures and complicated load cases is demonstrated, and the benefits of conducting shakedown-based design are discussed in comparison to conventional compliance and stress-based designs.