Development of a simulation dump truck dynamics model to estimate loads acting on its carrier and load platform when loading and dumping bulk loads

It is important for mining dump trucks to minimize the weight of the carrier and the load platform while maintaining a sufficient level of their rigidness and strength. This requirement significantly affects the weight of the transported material, the cost of transportation and, consequently, the economic efficiency of mining operations. Processes of loading and dumping of bulk loads, which is transported by dump trucks, make a significant contribution to reducing the service life of the carrier. Therefore, proper consideration of the bulk load dynamics is an important and relevant task. Contemporary systems for calculating the dynamics of solids allow for joint modeling with applications designed to calculate the dispersed body dynamics. This approach helps to obtain adequate loads in the pivots and force links of the model, to analyze the loading of the load platform, to asses the durability of the dump truck elements, to define the geometry of the load platform. In order to perform the simulation, it is required to develop a mathematical model of a dump truck, including all its key elements and subsystems, a model of the bulk load, and a model of the load platform. The purpose of the study is to develop a mathematical model of a mine dump truck to determine the loads in the pivots and force links connected to the carrier and the load platform for the strength calculations and durability analysis. The calculations are made with the combined use of the solids dynamics calculation system and the application to calculate the dynamics of dispersed bodies.

Designing simulation model for minimizing coal train unloading time: A case study of Kereta Api Logistik Company

The increase in coal production every year has influence the transport volume of coal trains of Kereta Api Logistik Company is getting higher. This increase causes the current number of train unloading equipment to be unable to keep up with this increase and has an impact on the poor performance of train unloading, which is indicated by the unachieved of train’s waiting time target. The coal train unloading system is a very complex system and many uncertainties occur, so the appropriate method to use is discrete event simulation. The simulation model is designed using the Simulation Arena software. The results of the simulation method are 4 alternative scenarios will be selected by the Bonferonni test. Scenario 4 has the highest reduction in train unloading operating time, which is 30.7%. The results of this study recommend the addition of a tool with a combination of 1 unit of Gantry Crane integrated with coal traveling hopper and 5 units of Dump Truck and for management, this recommendation can reduce high overtime costs every month and increase coal transport capacity so that coal transport profits will increase.

Identifikasi material dan perhitungan kembali tegangan tangensial barrel rear suspension dump truck EH 5000

Suspensi dump truck berfungsi sebagai peredam kejutan dari permukaan jalan, penyangga berat unit, memberikan kenyamanan pada operator dan menjaga kestabilan unit (empat roda selalu menyentuh tanah). Barrel adalah komponen penting dalam suspensi dump truck. Komponen tersebut berbentuk tabung pada suspensi dan berfungsi sebagai rumah untuk piston. Barrel yang bukan standar original Hitachi sering mengalami kerusakan. Penelitian ini bertujuan untuk mengetahui nilai kekerasan dan kekuatan tarik pada material barrel suspensi belakang, komposisi kimia dan struktur mikro pada material barrel suspensi belakang, dan nilai tegangan tangensial pada dinding barrel.Penelitian ini dilakukan dengan empat pengujian, yaitu uji kekerasan, uji tarik, uji struktur mikro dan uji komposisi kimia. Pengujian kekerasan dengan menggunakan alat uji kekerasan Brinell, pengujian tarik dengan menggunakan alat uji tarik (universal testing machine), pengujian komposisi kimia dengan alat spectrometer, dan pengujian struktur mikro dengan metallographic microscope. Sedangkam untuk mencari nilai tegangan pada dinding barrel dilakukan perhitungan tegangan tangensial.Hasil dari penelitian ini menunjukkan bahwa material barrel mempunyai nilai kekerasan rata rata 200,50 HB, nilai kekuatan luluh σy 433-494 MPa, nilai kekuatan tarik σu 740-751 MPa, kandungan pada material termasuk kategori baja 27 SiMn, struktur mikro pada material terdapat fasa ferrite dan pearlite, material aman terhadap beban statis, dan tegangan tangensial yang terjadi lebih rendah dari kekutan luluh.

COMPUTATIONAL AND EXPERIMENTAL METHOD FOR ESTIMATING THE RESIDUAL LIFE OF GEARS BASED ON VIBRATION MONITORING DATA

A computational and experimental method for estimating the residual life of gears in the inter-repair period is proposed. The method is based on the main provisions of the theory of vibration-pulse diagnostics of spur gears, developed at the OIM of the National Academy of Sciences of Belarus. The main performance criteria are the contact and bending endurance of the teeth. Accounting for changes in the value of the coefficient of internal dynamic load in the gearing during the operation of gears is carried out on the basis of vibration analysis during their vibration monitoring. The proposed method makes it possible to estimate the residual life of the gear mechanism at any stage of operation, providing the opportunity to organize the transition from planned preventive maintenance of machines to maintenance according to the actual condition. An example of estimating the residual life of a gear pair that limits the reliability of a two-row planetary gear motor-wheel of a heavy-duty dump truck is given. Keywords: gear transmission; vibration monitoring; residual life; inter-repair period; internal dynamic load in engagement

Produktivitas Peralatan Konstruksi Pada Proyek Jaringan Irigasi D.I Baliase Kanan 2 (Paket IV) Kabupaten Luwu Utara

Penggunaan peralatan konstruksi sangat berpengaruh terhadap pekerjaan di dunia teknik sipil, dalam hal ini khususnya alat berat. Sebagai upaya peningkatan produksi pertanian di provinsi Sulawesi Selatan, kementrian Pekerjaan Umum dan Perumahan Rakyat (PUPR) semakin memperluas jaringan irigasi yang sumbernya berasal dari bendungan baliase di Kabupaten Luwu Utara. Pada pembangunan jaringan irigasi ini, proses pekerjaan masih pada tahap penghamparan dan pemadatan tanah yang menggunakan 4 alat berta yaitu Excavator, Dump Truck, Dozzer, dan Vibrator Roller. Penelitian ini dilakukan dengan metode kuantitatif dengan cara pengamatan langsung dilapangan. Pengolahan data dilakukan untuk mengetahui produktivitas dari masing-masing alat dan melihat apakah peralatan yang digunakan pada pekerjaan penghamparan dan pemadatan tanah ini sinkron. Berdasarkan hasil penelitian diketahui produktivitas Excavator sebesar 631,299 m3/jam, DumpTruck sebesar 335,69 m3/jam, Dozer 603,405 m3/jam, dan Vibrator Roller 4987,5511 m3/jam. Dari hasil dapat dilihat bahwa produktivitas pada peralatan yang digunakan tidak sinkron yang mengakibatkan terjadinya Idle Time pada beberapa alat, oleh karena itu dilakukan perhitungan sinkronisasi alat . Dari hasil perhitungan didapatkan bahwa terjadi penambahan alat pada Dump Truck sebanyak 10 unit agar mengurangi idle time pada peralatan konstruksi.

Application of an improved mining complex for opencast mining of ore deposits

The purpose of the study is reducing the loss of mineral raw materials and increasing the efficiency of mining operations using a mining complex through the introduction of a new design and engineering solution that improves the equipment functionality. The study involves the analysis of known designs of mining equipment capable of providing the transformation of cyclic scooping of rock mass into its continuous loading, as well as screening of fine fractions from the ore mass. High productivity mining complexes are referred to a promising direction of mining equipment development. The article proposes an improved design of the mining complex, which allows to combine the extraction and loading process and ore mass grading. The improved mining complex is equipped with an annular conveyor with vibrating grids through which fines are screened into the accumulation hopper. From the accumulation hopper the small fractions are sent by means of a pneumatic conveying system to the bunker sections of a special-purpose hauler while the oversize product is loaded into a dump truck by a dump conveyor. The fine fractions of substandard ore collected in the bunker sections are sent for heap leaching. The fine fractions of conditioned ore are sent to the concentration plant to be processed. The proposed design and engineering solution employing an improved mining complex will reduce the cost of works and increase the recovery factor of mineral raw materials in the development of complex-structured deposits of ores characterized by natural concentration of small classes. Removal of fine ore fractions directly during the excavation and loading process can significantly reduce the dusting and decrease the loss of mineral raw materials from blowing and spilling of fine fractions.

Increasing life of pit dump truck motor-wheel gearboxes by introducing the monitoring of the actual technical condition

At present, Kuzbass coal strip mines pay great attention to improving quality performance of mining equipment operation, including reliability and durability of components and units. One of the ways of the performance improvement is decreasing number of unforeseen failures. To achieve this purpose a mine dump truck part diagnostics should be introduced into a maintenance service procedure. At the same time the process of diagnostics should not increase the machinery downtime, but effectively reveal a condition of motor-wheel gearboxes in the course of dump truck operation. The aim of the research is to increase the reliability and service life of motor-wheel gearboxes of large BelAZ dump trucks. Failure of a motor-wheel gearbox is a rare phenomenon, but the cost of a new gearbox can vary from 3.5 to 10 million rubles. That is why it is important to implement such methods of diagnostics, which allow revealing the condition of gearboxes in the shortest possible time and without disassembling corresponding units. Determination of the actual technical condition of motor-wheel gearboxes is possible by different methods: vibroacoustic; acoustic; thermal; physical and chemical analysis of spent operating materials. The studies showed that none of these methods can be used as a universal one. When justifying and selecting the most suitable method, different factors should be considered, including technological, or a combination of methods should be applied, which will reduce risks, but at the same time increase costs. It is necessary to develop a better diagnostic method based on the use of several methods simultaneously.