Hoist Mechanism Research Articles

Active Vibration Control of Nonlinear Elastic Wire Rope in Mine Hoisting System

Based on the importance of the safe operation of the mine hoist mechanism, an adaptive control method based on Fuzzy Sliding Mode Control (FSMC) was applied to synchronize the large-amplitude response of geometrically nonlinear elastic wire rope in mine hoist systems. To efficiently and precisely synchronize the lateral vibration of a wire rope under the adaptive synchronizing method, the control equation of the elastic wire rope was given considering the large von Karman geometrical deformation, and it was converted to a six-dimensional nonlinear dynamical system using third-order Galerkin discretization. Based on this dynamic system, the existing FSMC is improved, so that the improved control strategy will be available for the active dynamic control of multidimensional nonlinear dynamical systems. The research shows that the control strategy can effectively synchronize the large-amplitude response of wire rope, thus providing the basis for dynamic design, fault diagnosis, and safe operation of the mine hoist system.

Design and development of sub‐baric thermal processer for frying ofGulab jamun: A deep‐fat fried dairy product

AbstractA sub‐baric thermal processor (SBTP) was conceptualized, designed by 3D modeling and simulation for von mises stress analysis, deformation, and factor of safety. The auxiliary system components like electrical heater, surface condenser, vacuum pump, and frying cage with tiered trays were selected based on the design for a flexible capacity to prepare fried snack products and were integrated into the system for smooth functioning. Essential mechanical movements of the frying cage were controlled by frequency‐controlled planetary gear motor along with pneumatic system for rotary and vertical movements. The design concept was transformed into process, instrumentation, and manufacturing drawings. The fully automatic, microcontroller based, skid mounted, mobile SBTP was fabricated asper c‐GMP and 3‐A hygiene fabrication standards. Based on von mises stress analysis (135.79 MPa), the SBTP was fabricated from 4‐mm thick, food grade, acid‐resistant AISI‐316 stainless steel to withstand high vacuum environment. The factor of safety obtained was 1.50, which implies that vacuum vessel can practically withstand a stress up to 205 MPa. The operating process parameters of SBTP, temperature, process time, and pressure were controlled by custom‐made microcontrollers, programmed to work in auto mode. The rotation of frying basket was varied by inverter‐controlled variable frequency gear motor. The basket hoist mechanism was automated and controlled by microcontroller. Results showed that the sub‐baric product had lower oil content (22.74%) and the use of leavening agent could be eliminated due to the development of adequate porosity during sub‐baric frying. Sub‐baric friedGulab jamunballs at 118°C, 5 min and 48 kPa had a color comparable to the conventional fried balls (140°C, 5 min, 101 kPa) with a browning index of 164/94 and 169/103, respectively, for crust/crumb. From the above results, it concluded that sub‐baric thermal process is a potential alternative technique, which could be adopted by the dairy and food industry for the production of low‐fat dairy and food products.Practical ApplicationsThe developed sub‐baric thermal processer would lead to innovation, which can conveniently replace the conventional frying and soaking process with savings in use of frying oil and could also be applicable to similar other frying applications in the food processing industry especially in the preparation of snack products.

Mathematical modelling of bridge crane dynamics for the time of non-stationary regimes of working hoist mechanism

Mathematical modelling of bridge crane dynamics for the time of non-stationary regimes of working hoist mechanism

Commissioning Test of the Iradiator Gamma Merah Putih

Initialized with design phase in 2015, BATAN developed a gamma irradiator, namely the Iradiator Gamma Merah Putih (IGMP). Located in Puspiptek Serpong, the IGMP finished its construction in 2017. Commissioning test was performed for assuring that the installation is designed, constructed and installed according to the operational requirements. The commissioning test consists of cold and hot commissioning. Cold commissioning refers to testing the operation of the irradiator without radioactive sources. The test was carried out by doing a checklist on the operating table list. The test showed that in all operations, all irradiator equipment and systems are functioning well as per the requirements. It was then concluded that the irradiation facility was ready to receive radioactive sources. In July 2017, the gamma irradiator was loaded with 301 kCi of Cobalt-60 sources provided in 29 source rods distributed into three racks individually controlled by hoist mechanism. Hot commissioning was carried out by lifting up all radioactive sources, and then radiation exposures were measured. In the preliminary tests, there were some locations at the third floor, where the radiation exposures were too high. It was then be minimized by correcting the roof plugs positions and by adding lead material as additional shielding. Finally, measurements show that all radiation exposures were less than 1 μSv/h and safe for public.

Limitation of the dynamic load in the hoist mechanism of the shovel based on the additional drive

In the article, the results of studies of the synthesis of the optimal structure and parameters of the electromechanical system of the hoist mechanism of the rope shovel EKG-8I, which provides the limitation of dynamic loads, are presented. The procedure of structural-parametric synthesis is described, which is based on the determination of the required control actions, independent from the structure of the control system of the hoist mechanism. Control actions were found by solving the inverse dynamic problems for a given type of oscillatory motions of the dipper in the start-up and load change modes. Based on the expression of the obtained time dependencies through the phase coordinates of the system and its combinations, the structure and parameters of the control system were found. The found structure of the control system of the standard electric drive of the hoist mechanism and the additional drive ensures the implementation of a given law of motion of the dipper. The numerical simulation of the electromechanical system of the hoist mechanism with an additional drive confirmed the effectiveness of using the proposed approach of reducing the dynamic loads with maintaining the productivity of the excavator.

Study of the impact design factors to the oscillating process of the hoist mechanism

The questions of the impact design factors of the many-mass mechanical system to the oscillatingforce process during transient regimes of the hoist mechanism jib mobile crane operation are considered.The study with numerical methods with mathematic model describing transient regimes,appearing in the hoist mechanism drive of the automobile crane, with combustion engine equippedwas conducted. The four-mass dynamic model for estimation of the impact of different factors tothe dynamic loads was built. This model has identical ink margin as original. The realization thismodel with numerical Runge-Kutta method is done.Dynamic load of the system with comparative analysis of force of drive mass graphicsmethod was estimated. Conducted research showed that in basic the amplitude-frequencycharacteristic of oscillating process with accelerative-elastic parameters of the system is estimated.It is necessary to attend for accelerative-elastic parameters of the system during design for exclusionsuch negative effects as resonance and jumping.

Analyzing Vibration Suppression of Nuclear Power Crane with Model Coupling Mechanism and Structure

The nuclear power crane possesses strict safety requirements. Based on the special structure of its hoisting mechanism, it has two sets of independent lifting ropes to drive a hook synchronously and two pressure buffer devices on both ends of winding system’s balancing lever, in order to play protective roles and increase its working reliability. The flexible multi-body dynamics model which coupled mechanism and structure of the nuclear power crane is constructed when broken accident of rope occurs in the lifting process from the ground or smooth lifting. The importance of a buffer damping device installed in crane hoist mechanism has been proved through the vibration simulation about wire rope at the failure state. And the vibration of mechanism and the main girder structure is remitted and controlled at the time of failure in operation. The most important advantage is that has improved the safety of nuclear power crane.

Recent advancements in Dragline control systems

This paper discusses about the robust machine “Dragline”, from century old techniques employed for power transmission, control and operation to the recent trends. Dragline is mostly used in mining sector for removal of overburden as it is highly economical in comparison to the usage of shovel–dumper combination of the same, however the deployment of dragline is subjected to the geographical conditions of the mine. Dragline in general mostly comprises Drag, Hoist and Swing mechanism. For the Drag, Hoist and Swing operations earlier DC machines are used with Ward–Leonard control mechanism, but recently due to advancements in power electronic devices AC motors found their application for the same due to their less maintenance costs and also reducing the number of machines resulting in increasing the overall efficiency. Also, gear less power transmission techniques are in place. In parallel, the control techniques are also getting evolved and automation is taking place starting with Swing mechanism extending to the whole operation.

Multi-Objective Optimization Design for Body Hoist Mechanism of Mining Dump Truck

The rear multi-stage cylinder direct-acting hydraulic body hoist mechanism is widely used in mining dump truck. The working principle of the body hoist mechanism is introduced. The dumping process is simplified through the introduction of “dumping line” and the variation of ore mass and hoist torque are analyzed. The optimization design of the position of body hoist mechanism is done using Maple software on the basis of direct search method aimed at minimizing the initial hoist force and the stroke of cylinder and maximizing the hoist force arm when the second stage cylinder starts to stretch out.

Investigation of a failed axle of a reduction gearbox

After 11,300 h of operation, one of the axles of the reduction gearbox of the hoist mechanism of a dockside crane failed due to the propagation of a fatigue crack. The axle contained two gears, the largest of which was mounted swith a key, while the smallest gear was an integral part of the axle. On both ends of the axle a bearing was mounted: one cylindrical bearing and one spherical roller bearing (locating bearing). The axle was made from 17CrNiMo6 steel, and the machined gear teeth were case carburised. The failure of the axle occurred in the middle between both bearings of the axle, on a non-contacting part of the gear machined on the axle. During visual inspection striations were observed on the fracture surface and three separate crack initiation zones could be observed on three neighbouring gear teeth. The ratio of final fracture versus fatigue fracture was low, indicating a low nominal stress on the axle. The three initiation sites were investigated with optical microscopy and SEM, and clear indications of a ductile overload fracture were found. In an etched longitudinal section of one of the gear teeth where initiation took place several cracks could be observed in the hardened case of the tooth. The hardness at the initiation site was found to be 777 HV, while the hardness at the final fracture (diametric position relative to the initiation of the crack) was found to be lower, namely 722 HV. It was concluded that at the initiation site during the case carburisation quenching cracks were formed, which then propagated through the whole section of the axle under relatively low operation load.

차세대 컨테이너크레인에 대한 고찰

본 기술논문에서 18,000 TEU급 초대형 선박에 대응하는 차세대 컨테이너크레인의 규격 및 성능을 검토하였다. 컨테이너선의 발달 과정을 연대순으로 살핀 후에 기존에 설치되어 운영중인 컨테이너크레인의 특성을 파악하였고 세계각처에서 수행되고 있는 컨테이너크레인에 관한 연구동향을 분석하였다. 분석한 결과를 토대로 2014년 이후에 등장할 차세대 컨테이너크레인의 규모 및 성능을 예측하였다. 검토된 사항은 컨테이너크레인의 구조, 트롤리와 호이스트의 메커니즘, 제어방식, 아웃리치, 백리치, 레일게이지, 하역능력, 안정성 및 내구성 등이다. In this article. the specifications of a future container crane for a 18,000 TEU megaship are investigated After studying the transitions of containerships through the past half century, the characteristics of the past and current container cranes are outlined. together with various research trends throughout the world Upon these results, the size and performance of the container crane that will be used beyond the year 2014 are forecast. Specifically, the structure, trolley and hoist mechanism, control method, outreach. backreach, rail gage, loading capacity, stability, durability, and others are summarized.

New design of hoist mechanism for electric overhead traveling cranes

New design of hoist mechanism for electric overhead traveling cranes

Mathematical Programming Solution of a Hoist Scheduling Program

Abstract This paper describes a mixed integer programming model of a process during which electronic circuit boards are chemically treated in a sequence of tanks. The boards must remain in these tanks for periods of time lying within specified bounds. A hoist mechanism is to be programmed to place boards into tanks, remove boards from tanks, and transport boards between tanks, so as to maximize the throughput of the system. Computational experience and a detailed example are given.