Design Of Crane Research Articles

Stress Concentration Modelling in Internal Stiffeners of Ship-to-Shore Quay Cranes Legs Due to Structural Heightening

This paper presents a study on the modelling and estimation of stress concentration at the tips of leg stiffeners in ship-to-shore (STS) quay cranes, which is intensified in those on the sea-side leg extensions, which are more prone to crack formation, notably following structural heightening of the cranes. A computer-simulated database was generated, incorporating mechanical parameters and geometric features that impact stress concentration. These variables can then be integrated as inputs into a multiple linear regression model (MLR). This methodology offers an alternative to the finite element method (FEM) for the computation of stress concentration and deformations. At the same time, the statistical significance of the parameters influencing this scenario is determined, ensuring a comprehensive assessment of their impact on the studied phenomenon. The research underscores the importance of incorporating stress concentration and structural geometry considerations into crane design or modification, given their crucial role in preserving the remaining lifecycle of the structure. Crack initiation is significantly intensified in regions characterised by high stress concentrations, particularly in areas where there are geometric changes at the tips of the stiffeners, where local stiffness is altered. All of this is in combination with work cycles under the supported loads.

Desain dan Analisis Finite Elemen Rangka Gantry Crane Menggunakan Software Autodesk Inventor Profesional 2024

Currently, the gantry crane still uses steel material. The steel is protected using a coating paint to minimize the impact of corrosion. However, this method is inefficient given the high rate of corrosion due to its coastal location. This also causes maintenance issues because repainting must be done regularly and periodically. Additionally, not all equipment has annual maintenance funding. The aim of this study is to design and analyze the stress of a 9-ton capacity gantry crane using Aluminium 6061 material. Finite element analysis was conducted using Autodesk Inventor Professional 2024 software. The results of this study indicate that the gantry crane frame is safe to use because the von Mises stress analysis result of 2,778 MPa is still below the yield strength of Aluminium 6061 material, which is 275 MPa. A safety factor of 2.07 shows that the gantry crane design is very safe to withstand loads up to 9 tons.

Design of an Overhead Crane in Steel, Aluminium and Composite Material Using the Prestress Method

The present research describes a design of an overhead crane using different materials with a prestress method, which corresponds to an external compression force with the aim of reducing the displacement of the beam due to the external load. This study concerns a bridge crane with a span length of 10 m, with a payload equal to 20,000 N and an estimated fatigue life of 50,000 cycles. Three different materials are studied: steel S355JR, aluminium alloy 6061-T6 and carbon fibre-reinforced polymer (CFRP). These materials are analysed with and without the contribution of the prestress method. In reference to the prestressed steel solution (which has a weight equal to 79% of the non-prestressed configuration), this study designed an aluminium solution that is 50.7% of the weight of the steel one and a composite solution that is always 20.3% of the steel configuration. In combining the methods, i.e., the materials and prestress, compared to the non-prestressed steel solution with a weight evaluated to be 758 kg, the weight of the aluminium configuration is equal to 40% of the traditional one, and the composite value is reduced to 16%, with a weight of 121 kg.

Research on energy consumption evaluation and energy-saving design of cranes in service based on structure-mechanism coupling

Aiming at the problem that the life cycle energy consumption index of hoisting machinery is difficult to be objectively quantified, a crane energy consumption evaluation calculation method based on the working cycle of the service period is proposed, the typical service working mode of the crane is analyzed, and the working cycle process of the mechanism is clarified. On this basis, the stress cycle characteristics of the crane structure during the service period are determined based on the coupling relationship between the mechanism and the structure, which lays the foundation for accurately evaluating the life index of the crane. According to the relationship between the load rate and effective power of each mechanism during the service period of the crane, the calculation method for the evaluation and calculation of the structure energy consumption during the service period of the crane is studied. Finally, the crane is designed based on the concept of absolute service safety, and an optimal design model of the main girder structure of the crane with the goal of the lowest energy consumption in service is established. Using the research method of this paper to study a certain type of bridge crane, the energy consumption of the hoisting machinery during its service period is not only related to the accumulation of the operating characteristics of the mechanism but also related to the characteristic parameters such as the structure self-weight. The comprehensive evaluation of energy consumption provides an effective quantitative method and a reliable green design theory for crane design.

Study of the variation of the leading edge of a railway crane on the aerodynamic characteristics

The front body design of the railway crane is flat or bluff type. The design causes a large drag, so the railway crane requires high fuel consumption to drive. Therefore, this study aims to modify the front body of the railway crane by applying the shape of the leading edge to reduce drag. This research also investigates the effect of leading-edge angles on aerodynamic characteristics. The method used is computational fluid dynamics, using the flow simulation feature of the Solidworks research licence software. This study considered three variations of leading edge angle (40°, 45° and 50°). The simulation results show that the larger the leading edge angle, the lower the drag coefficient value. In addition, the simulation shows that there is a high air pressure at the front of the railway crane with the bluff shape, while the modified railway crane with the leading edge applied has a lower air pressure at the front. Furthermore, the results and discussion in this article present the simulation results showing the velocity streamline and pressure contour of each model.

Design and Analysis of Lifting Carriage of 4T Overhead Stacker Crane

The Overhead Stacker Crane is a hybrid device that combines the features and constructions of "Industrial Forklifts" and "Electric Overhead Cranes." Stacker cranes are equipment with varied levels of automation that are used to store materials. They travel along the aisles of the operating areas, where they enter, position, or extract the material. This type of crane is widely used in assembly shops, production stores, warehouses, etc. Each application needs customizing. The lifting carriage of different overhead stacker crane design is studied in this study. The new design has two advantages: the lifting carriage is bracketed to the mast of the overhead stacker, and the new lifting mechanism is more compact. The most common structure configurations are single-mast and twin-mast constructions. Single-mast structures are used for investigation in our research. A live example has been chosen, and several design engineering stages have been implemented, with the goal of achieving compliance with safety-related standards as well as possible enhancements for future consideration. All the concerned parts have been 3D modelled, analyzed using classical means as well as advanced means of FEA. The goal of using design engineering concepts is to provide a verified design with documentation that can be manufactured with or without indicated improvements. Static analysis of identified parts is performed using both hand calculation and the FEA approach.

Особенности работы кранового группового электропривода с частотным управлением на морском судне

One of the most important tasks to increase efficiency and reliability of modern sea vessels is the study of the operation of electric drives with frequency control. There is a sufficient number of scientific studies in which analysis and research is carried out on the topic of frequency control of electric drives. Problems occur when operating special-purpose sea vessels equipped with a powerful crane with a lifting capacity of 250 tons. The ship crew when working in the open sea, cannot fully operate the cargo crane at full speed, since it is suddenly switched off by the protection and an emergency occurs. In this regard, it is relevant to improve the use of powerful group electric drives on sea vessels. The authors have used a passive experiment method to study the operation of six electric motors with a power of 400 kW, which drive the winch of the crane main hook. The operation of the frequency converter and multichannel oscilloscope has been constantly monitored. Using the standard functions of the frequency converter control system allows you to monitor and obtain oscillograms of six parameters simultaneously: motor torques, active motor powers and engine rpm speed, total winch current. The necessary adjustments and settings of the frequency converter control system are carried out by changing the parameterization of the encoder signal processing card. The design of a pedestal crane with a lifting capacity of 250 tons on the pipe-laying vessel Seven Vega is considered. Experimental oscillograms have been obtained characterizing the operation of the crane main hook winch. The moment of trip (knockout due to overload) has been recorded at the maximum speed of one of the six drive electric motors. It has been established that such protection makes it impossible to continue lifting or lowering the load. The conducted studies have shown that for encoders used in a group crane electric drive, it is necessary to use the law of calculation of the rotation speed using the full duration of the pulse period of one channel. After changing the parameterization of the encoder signal processing map, which provides calculation of the rotation speed of each of the six electric motors, long-term tests have been carried out. The tests results have shown the proper operation of the crane main hook winch at maximum speeds. The results of the conducted research make it possible to ensure high-quality operation of a group crane electric drive with frequency control. As a result of the study, it is established that when asymmetry of pulse duration is detected in the operation of optical encoders, it is necessary to change the speed calculation method of the frequency converter to use the full duration of the pulse period of one channel, and not the difference between the fronts or drops of the pulses of four channels. The experience of the conducted research and repair and adjustment work can be used in various electrical complexes that use group electric drives with Siemens frequency converters.

Research and analysis of tower crane load behavior when the rope breaks

The object of research is the behavior of the load of the tower crane during the break of the sling. One of the most problematic areas is the safety of work and the prevention of emergency situations. Despite the presence of mandatory safety measures, during cargo transportation, one of the sling branches may be destroyed due to the presence of a dynamic component during the operation of the crane, or errors of the slinger when securing the cargo. Also, the presence of hidden internal or unnoticed defects in the sling construction itself cannot be ruled out. Also, one of the most problematic places is the chaotic fluctuations of the load, which negatively affect the stability of the crane and safety. The paper describes the case of the destruction of one of the branches of a two-rope sling during the transportation of a long product by a tower crane. The proposed method of cargo behavior analysis is based on the use of a dynamic description of cable system failure modes within the framework of setting and solving differential-algebraic equations. This makes it possible to more accurately describe the behavior of the cargo when the sling breaks. The obtained results show that the application of the proposed method makes it possible to bring the mathematical model of the two-link mathematical pendulum significantly closer to the actual mutual oscillations of the load during the sling break. This is due to the fact that the proposed method has a number of features, in particular, high sensitivity to changes in the behavior of the cargo and a quick reaction to a rope break. These results can be used in practice in the design and operation of tower cranes. Thanks to the application of the proposed method, it is possible to obtain accurate values of cargo behavior indicators and timely detection of a rope break. Compared to similar known methods, this method has such advantages as high efficiency, reliability and safety of operation.

Сравнительная оценка энергетических затрат при перемещениях кранов-штабелеров

Within the framework of the put forward hypothesis that energy costs of working movements of the links of racking stacker cranes are inextricably linked to the shape of the working area of the warehouse in which the crane operates, to reduce energy costs, it was pro-posed to use a rotating boom in the design of the stacker crane. With the help of program implementations of mathematical models of stacker cranes of traditional bicycle design and the proposed design with a rotating boom, it became possible to determine the average energy costs for all possible movements of loads of the same mass within the corresponding working areas of these designs. For this purpose, systems of differential equations in Cauchy form were developed, where dissipation of energy was taken into account. The total value of work of crane drives during acceleration and braking was determined. The latter were carried out with constant accelerations, and the movement after acceleration — with constant speeds. The developed simulation mathematical models of cranes of traditional design and the proposed design with a rotating boom allow to determine the energy costs in the drives when moving the crane links along the given trajectories. According to the criterion of average total energy costs, adopted for all possible combinations of movements within areas of the same capacity of one hundred square meters, the stacker crane of the proposed design has an advantage over the crane of traditional design. This makes it possible to significantly reduce energy costs when using such cranes in warehouses and hangars. It is reasonable to recommend the use of a stacker crane of the developed design in warehouses of round shape — it will allow to reduce significantly the energy costs when using such cranes in warehouses and hangars.

Azaindolizine proton cranes attached to 7-hydroxyquinoline and 3-hydroxypyridine: a comparative theoretical study.

Theoretical design of several proton cranes, based on 7-hydroxyquinoline and 3-hydroxypyridine as proton-transfer frames, has been attempted using ground and excited-state density functional theory (DFT) calculations in various environments. Imidazo[1,2-a]pyridine, pyrazolo[1,5-a]pyridine and benzimidazole were considered as proton crane units. The proton crane action requires the existence of a single enol-like form in the ground state, which under excitation goes to the end keto-like one through a series of consecutive excited-state intramolecular proton transfers (ESIPT) and twisting steps with the participation of a crane unit, resulting in a long-range intramolecular proton transfer. The results suggest that 3-hydroxypyridine is not suitable for a proton-transfer frame and 8-(imidazo[1,2-a]pyridin-2-yl)quinolin-7-ol and 8-(pyrazolo[1,5-a]pyridin-2-yl)quinolin-7-ol behave as non-conjugated proton cranes, instead of tautomeric re-arrangement in the latter, which was thought to be possible.

Statistical analysis of forest machines ergonomic parameters

The main technology currently used in wood harvesting in Russia is the cut-to-length technology (CTL) based on the use of two machine types: harvesters and forwarders. Powerful and manoeuvrable hydraulic manipulators (cranes) are a main part of the equipment of both the harvester and the forwarder. A statistical analysis of ergonomic parameters of the manipulator control system equipped with partial automation option is described in this article. Two machines were studied in natural field conditions. Differences in the frequency and duration of telescopic extension boom control activations were identified. The distributions of the extension boom use parameters for the crane of the logging machines were defined. It can be used to build various models for the analysis of promising crane design solutions. It is determined that the duration of the rocker switch single press has a log-normal distribution and the period between switch activations has an exponential distribution.

Review and analysis of damage and existing systems of protecting tower cranes under the influence of a blast wave

Problem. The problem of assessing the technical condition of stationary tower cranes of various types by expert organizations in order to determine the possibility of their further operation and the methods of capital repair is relevant. At the same time, one should take into account the nature of the consequences of damage to metal structures and the type of repair, if it is at all possible. The topic of the article is of a practical nature. An attempt was made to have an initial representation and visual analysis of the condition of different types of tower cranes under the conditions of explosive air shock waves depending on the distance to the cranes. The article attempts to substantiate the consequences of the destruction of metal structures, mechanisms or protection systems and to point out some regularities that require close attention during the operation of tower cranes and their further research. Goal. The purpose of the work was to make a damage survey of the different types of tower cranes that have been damaged and their existing protection systems and to provide assumptions for further research on the stability of tower cranes in the conditions of air shock waves. Methodology. The approaches adopted in the work to solve the set goal are based on the conditional division into categories of damage to stationary tower cranes under the action of air shock waves. The results. The analysis of damage to tower cranes will make it possible to take into account in the future the development of typical projects in accordance with the technical documentation regarding their disassembly-assembly, types of repairs, etc. Originality. The study of the stability of tower cranes under the conditions of air shock waves is a rare and specific direction in the field of engineering research. Therefore, the results of this study will fill the gaps in scientific literature and engineering practice. Practical meaning. The results of the study can lead to the development of new approaches and recommendations for the design of tower cranes taking into account possible air shock waves. This will allow engineers to create safer and more reliable designs for working in hazardous environments

Force calculation and new design of the grip unit pliers metallurgical crane

In the rolling shops of metallurgical enterprises connected with the processing of steel ingots in the preparation (slabbing, blooming) well taps with pincer grabbers are used. Such cranes work in the sections of heating wells, where they are used, first of all, for planting ingots in the well and issuing them for rolling after heating. In addition, cranes can be used to perform auxiliary operations for well maintenance and equipment repair. During the design processing of tong grippers of such cranes, there is a need to determine the ingot clamping forces, which in this gripping device are related to the weight of the ingot itself and the weight of the tongs of the crane. In addition, the design features of the clamping zone itself are of great importance, that is, the design of the parts that transfer the clamping forces to the ingot. These parts are called cores. It is clear that the clamping force and the design of the cores must guarantee reliable retention and safe movement of the ingot. During the operation of the crane, the cores are subjected to a wide range of loads: shock, compressive, crushing loads from impact. At the same time, being in contact with the heated ingot, they themselves heat up to the same temperature. And because they are periodically cooled in tanks with water, they work even in conditions of cyclic heat changes. The design and physical condition of the cores are of great importance for the reliability of the tick gripper. Untimely replacement of cores can lead to negative consequences during ingot retention, cause it to break off with the destruction of the circle, damage to floor equipment and danger to service personnel. Several options for new, more effective designs are proposed in the work based on the force calculation of the pincer gripper and the analysis of the advantages and disadvantages of modern core designs. The authors created a mathematical model of the interaction between the core and the ingot to check the depth of penetration of the core into the body of the ingot and compared it with the indicators of known cores. It was found that at the ingot release temperatures, the depth of penetration into the body of the ingot for cores of the new design is 4 times less than for conventional conical cores. The use of these designs will ensure the reliability of the gripping device while simultaneously improving the quality of the workpiece by reducing the number of cracks and dips associated with damage to the faces of the ingot from deep indentation of the cores

Some points when designing tower crane foundations

With the current construction requirements of high-rise buildings, the demand for tower cranes is increasing. It is a construction support device, which helps to transport materials in large quantities quickly and save time. Currently, in the country, the documents on the design, manufacture and safe operation of tower cranes are quite complete. However, there are no guidelines/standards on specialized construction design for tower crane foundations. The majority of construction engineers do not determine the complete and correct tower crane foundation calculation procedure. The selection of references for calculation is also not simple. Therefore engineers often rely on experience, not much in fact, to design. This leads to difficulties in design practice and costs. From the above actual needs, a draft of the tower crane foundation calculation has been compiled. Here are some issues to keep in mind when designing tower crane foundations.

Dynamic effects on the lattice boom crane due to the wind, moving load and earthquake events

The present research concerns the evaluation of the dynamic effect on lattice boom cranes. The dynamic actions involved in this research are: wind, moving load and earthquake, assumed as time-varying actions. The research starts with the design of a large crane by adopting classical standards for these structures (UNI EN 13001 series). The elaborations were performed by analytical methods followed by solid model building and finite element analysis (Solidworks® and Ansys® software). The next step was to define the aforementioned loads acting on these structures. The wind action model was compared with the static approach. Payload displacement induces high-intensity actions on the crane structure; to better understand these effects, several load curves were simulated. The last action considered is the earthquake phenomenon, which is not usually adopted to design this type of structure.

Modified settlement‐stability‐optimization method for numerical foundation design of tower cranes

AbstractThe static design of foundations for tower cranes is mostly based on calculations of structural safety like tilting, sliding and groundbreaking. Settlement calculations for evaluating the inclination of the crane, which is restricted by the suppliers of tower cranes , are essential for safe and economic foundation solutions, too. Based on the experience of more than 280 tower crane positions throughout Austria and Germany the method of Müllner & Meister has been extended satisfying the normative and crane specifically requirements and represents an obligation of one of the biggest building contractors in Europe in the sense of today's resource‐saving management.

Control of a Double-Pendulum Overhead Crane System Based on Hierarchical Sliding Mode Control Techniques

The double-pendulum overhead crane system belongs to a class of underactuated mechanical systems, which is challenging to control due to its strong nonlinearities. This study deals with the nonlinear controller design for a double-pendulum overhead crane based on hierarchical sliding mode control with state-dependent switching gain. The equivalent and switching controls are obtained with the aid of first-level and second-level sliding surfaces. The asymptotic stability of sliding surfaces is proved theoretically and also shown graphically. Numerical simulations show that the proposed controller performs better than conventional hierarchical sliding mode control. The proposed controller effectively suppresses the load and hook swing and precisely controls the trolley’s displacement. It has strong robustness to the payload displacement and the change of the crane parameters.

Математическое и компьютерное моделирование колебания системы «груз-балка» козлового крана

Introduction. Gantry grappling cranes are the main equipment for cargo transportation in the technological processes of mining and enrichment of rocks. During the operation of the crane, undesirable effects such as the rocking of the payload occur, which in turn affects the dynamic state of the crane beam. Materials and methods. To solve this problem, methods of mathematical and computer modeling of a system with two degrees of freedom were used. To identify the influence of different combinations of the combination of payload mass and cable length on oscillation frequencies, a computational experiment was carried out and the response surface of the oscillation frequency function was constructed. The natural oscillation frequencies of the beam were determined by the finite element method in the NASTRAN program. Results. The results of mathematical modeling were graphs of changes in the angle of deviation of the cable from the vertical and the movement of the trolley, the response surface of the frequency of oscillation of the payload from the length of the cable and the weight of the cargo. Discussion. A comparison of the simulation results of cargo vibrations and crane beam vibrations showed the proximity of the values of the frequencies of the payload vibrations and the gantry crane design, which justifies the need for further analysis of the frequency response of the crane beam to the disturbance of the payload vibration force. Conclusion. The frequency of vibrations of the load significantly affects the static and vibration strength of the crane beam of the gantry crane Resume. The research results can be useful in the development of technical solutions for the engineering implementation of promising gantry crane designs.

Light-weight design of an overhead crane’s girder with a non-symmetric box cross-section

The proper choice of material and geometric properties of the girder of the bridge crane can significantly reduce its weight and production cost. This research presents the weight optimization of the main girder with a non-symmetric box-like cross-section. The strength analysis in characteristic points of the critical cross-section and the local stability of plates were conducted using Eurocodes. This study aimed to prove that a proper choice of geometry for the cross-section plates and their additional design elements can have a meaningful impact on the weight. The optimization procedure was done using Water Evaporation Optimization (WEO) algorithm, with the implementation of all necessary criteria and conditions which must be fulfilled. This study revealed that the application of the light-weight design philosophy to the structure of the main girder could significantly reduce its weight, which is verified in the existing examples of double-beam bridge cranes. Achieved savings in girder weight are between 24.43% and 34.73%, dependingly on the considered example. Also, the study showed the influence of the chosen material on the steel girder’s optimum weight and geometric parameters. Depending on the studied example of the bridge crane and selected material, the WEO algorithm gave the same solution through simulations. The value of the optimum weight had a slight deviation at the second decimal place, which is neglectable. The algorithm successfully avoided the trap of getting into the local minimum during the search. In the end, it can be stated that the application of the WEO algorithm was successful in the considered engineering problem since it was the optimization of a complex steel structure with 11 variables and more than 20 constraint functions.

Perancangan Single Girder Gantry Crane 2 Ton di PT Spindo Unit VI

In carrying out the design process, the main factor that must be considered is the lifting strength of the crane against the maximum load borne. Because the inaccuracy of the design process can result in malfunctions, even causing work accidents. Therefore, it is necessary to do the right design so that it can be used safely. In this design, the design of a lifting aircraft with a single girder gantry crane is designed with a lifting capacity of up to 2 tons, a lifting height of 4 meters, and a transfer width of 5 meters.. The design method used is by substituting the values ​​and other factors needed into the known equations to obtain the final result. To determine the maximum tensile strength of the load in this crane design, the equation for the maximum tensile force is used to obtain a result of 633.12 kg. Then for the steel rope chosen in this design is the 222 wire construction with parallel positions. By using the equation for resistance of the motor to movement, the power needed to move the crane is also 23,215 HP